@article {pmid32657581,
year = {2020},
author = {Wu, L and Chen, X and Wei, W and Liu, Y and Wang, D and Ni, BJ},
title = {A Critical Review on Nitrous Oxide Production by Ammonia-Oxidizing Archaea.},
journal = {Environmental science & technology},
volume = {},
number = {},
pages = {},
doi = {10.1021/acs.est.0c03948},
pmid = {32657581},
issn = {1520-5851},
abstract = {The continuous increase of nitrous oxide (N2O) in the atmosphere has become a global concern due to its property as a potent greenhouse gas. Given the important role of ammonia-oxidizing archaea (AOA) in ammonia oxidation and their involvement in N2O production, a clear understanding of the knowledge on archaeal N2O production is necessary for global N2O mitigation. Compared to bacterial N2O production by ammonia-oxidizing bacteria (AOB), AOA-driven N2O production pathways are less-well elucidated. In this review, we synthesized the currently proposed AOA-driven N2O production pathways in combination with enzymology distinction, analysed the role of AOA species involved in N2O production pathways, discussed the relative contribution of AOA to N2O production in both natural and anthropogenic environments, summarised the factors affecting archaeal N2O yield, and compared the distinctions among approaches used to differentiate ammonia oxidizer-associated N2O production. We then put forward perspectives for archaeal N2O production and future challenges to further improve our understanding of the production pathways, putative enzymes involved and potential approaches for identification in order to potentially achieve effective N2O mitigations.},
}
@article {pmid32655535,
year = {2020},
author = {Wang, L and Pang, Q and Peng, F and Zhang, A and Zhou, Y and Lian, J and Zhang, Y and Yang, F and Zhu, Y and Ding, C and Zhu, X and Li, Y and Cui, Y},
title = {Response Characteristics of Nitrifying Bacteria and Archaea Community Involved in Nitrogen Removal and Bioelectricity Generation in Integrated Tidal Flow Constructed Wetland-Microbial Fuel Cell.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {1385},
doi = {10.3389/fmicb.2020.01385},
pmid = {32655535},
issn = {1664-302X},
abstract = {This study explores nitrogen removal performance, bioelectricity generation, and the response of microbial community in two novel tidal flow constructed wetland-microbial fuel cells (TFCW-MFCs) when treating synthetic wastewater under two different chemical oxygen demand/total nitrogen (COD/TN, or simplified as C/N) ratios (10:1 and 5:1). The results showed that they achieved high and stable COD, NH4+-N, and TN removal efficiencies. Besides, TN removal rate of TFCW-MFC was increased by 5-10% compared with that of traditional CW-MFC. Molecular biological analysis revealed that during the stabilization period, a low C/N ratio remarkably promoted diversities of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) in the cathode layer, whereas a high one enhanced the richness of nitrite-oxidizing bacteria (NOB) in each medium; the dominant genera in AOA, AOB, and NOB were Candidatus Nitrosotenuis, Nitrosomonas, and Nitrobacter. Moreover, a high C/N ratio facilitated the growth of Nitrosomonas, while it inhibited the growth of Candidatus Nitrosotenuis. The distribution of microbial community structures in NOB was separated by space rather than time or C/N ratio, except for Nitrobacter. This is caused by the differences of pH, dissolved oxygen (DO), and nitrogen concentration. The response of microbial community characteristics to nitrogen transformations and bioelectricity generation demonstrated that TN concentration is significantly negatively correlated with AOA-shannon, AOA-chao, 16S rRNA V4-V5-shannon, and 16S rRNA V4-V5-chao, particularly due to the crucial functions of Nitrosopumilus, Planctomyces, and Aquicella. Additionally, voltage output was primarily influenced by microorganisms in the genera of Nitrosopumilus, Nitrosospira, Altererythrobacter, Gemmata, and Aquicella. This study not only presents an applicable tool to treat high nitrogen-containing wastewater, but also provides a theoretical basis for the use of TFCW-MFC and the regulation of microbial community in nitrogen removal and electricity production.},
}
@article {pmid32636492,
year = {2020},
author = {Qin, W and Zheng, Y and Zhao, F and Wang, Y and Urakawa, H and Martens-Habbena, W and Liu, H and Huang, X and Zhang, X and Nakagawa, T and Mende, DR and Bollmann, A and Wang, B and Zhang, Y and Amin, SA and Nielsen, JL and Mori, K and Takahashi, R and Virginia Armbrust, E and Winkler, MH and DeLong, EF and Li, M and Lee, PH and Zhou, J and Zhang, C and Zhang, T and Stahl, DA and Ingalls, AE},
title = {Alternative strategies of nutrient acquisition and energy conservation map to the biogeography of marine ammonia-oxidizing archaea.},
journal = {The ISME journal},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41396-020-0710-7},
pmid = {32636492},
issn = {1751-7370},
support = {548565//Simons Foundation/ ; 329108//Simons Foundation/ ; 41907027//National Natural Science Foundation of China (National Science Foundation of China)/ ; 21777155//National Natural Science Foundation of China (National Science Foundation of China)/ ; 21322703//National Natural Science Foundation of China (National Science Foundation of China)/ ; 41530105//National Natural Science Foundation of China (National Science Foundation of China)/ ; 91851210//National Natural Science Foundation of China (National Science Foundation of China)/ ; NNF16OC0021818//Novo Nordisk Fonden (Novo Nordisk Foundation)/ ; OCE-1046017//National Science Foundation (NSF)/ ; DEB-1664052//National Science Foundation (NSF)/ ; },
abstract = {Ammonia-oxidizing archaea (AOA) are among the most abundant and ubiquitous microorganisms in the ocean, exerting primary control on nitrification and nitrogen oxides emission. Although united by a common physiology of chemoautotrophic growth on ammonia, a corresponding high genomic and habitat variability suggests tremendous adaptive capacity. Here, we compared 44 diverse AOA genomes, 37 from species cultivated from samples collected across diverse geographic locations and seven assembled from metagenomic sequences from the mesopelagic to hadopelagic zones of the deep ocean. Comparative analysis identified seven major marine AOA genotypic groups having gene content correlated with their distinctive biogeographies. Phosphorus and ammonia availabilities as well as hydrostatic pressure were identified as selective forces driving marine AOA genotypic and gene content variability in different oceanic regions. Notably, AOA methylphosphonate biosynthetic genes span diverse oceanic provinces, reinforcing their importance for methane production in the ocean. Together, our combined comparative physiological, genomic, and metagenomic analyses provide a comprehensive view of the biogeography of globally abundant AOA and their adaptive radiation into a vast range of marine and terrestrial habitats.},
}
@article {pmid32634668,
year = {2020},
author = {Shi, X and Gao, G and Tian, J and Wang, XC and Jin, X and Jin, P},
title = {Symbiosis of sulfate-reducing bacteria and methanogenic archaea in sewer systems.},
journal = {Environment international},
volume = {143},
number = {},
pages = {105923},
doi = {10.1016/j.envint.2020.105923},
pmid = {32634668},
issn = {1873-6750},
abstract = {Sulfide and methane emissions always simultaneously exist in natural environment and constitute a major topic of societal concern. However, the metabolic environments between sulfate-reducing bacteria (SRB) and methanogenic archaea (MA) exist a great difference, which seems to be opposite to the coexisting phenomenon. To explore this issue, the comprehensive biofilm structures, substrate consuming and metabolism pathways of SRB and MA were investigated in a case study of urban sewers. The results showed that, due to the stricter environmental requirements of MA than SRB, SRB became the preponderant microorganism which promoted the rapid generation of sulfide in the initial period of biofilm formation. According to a metagenomic analysis, the SRB appeared to be more preferential than MA in sewers, and the preponderant SRB could provide a key medium (Methyl-coenzyme M) for methane metabolism. Therefore, the diversity of MA gradually increased, and the symbiosis system formed preliminarily. In addition, via L-cysteine, methane metabolism also participated in sulfide consumption which was involved in cysteine and methionine metabolism. This phenomenon of sulfide consumption led to the forward reaction of sulfide metabolism, which could promote sulfide generation while stabilizing the pH value (H+ concentration) and S2- concentrations which should have inhibited SRB and MA production. Therefore, the heavily intertwined interactions between sulfide and methane metabolism provided environmental security for SRB and MA, and completely formed the symbiosis between SRB and MA. Based on these findings, an ecological model involving synergistic mechanism between sulfide and methane generation is proposed and this model can also improve understanding on the symbiosis of SRB and MA in the natural environment.},
}
@article {pmid32634643,
year = {2020},
author = {Lin, Z and Huang, W and Zhou, J and He, X and Wang, J and Wang, X and Zhou, J},
title = {The variation on nitrogen removal mechanisms and the succession of ammonia oxidizing archaea and ammonia oxidizing bacteria with temperature in biofilm reactors treating saline wastewater.},
journal = {Bioresource technology},
volume = {314},
number = {},
pages = {123760},
doi = {10.1016/j.biortech.2020.123760},
pmid = {32634643},
issn = {1873-2976},
abstract = {To reveal nitrogen removal mechanisms under environmental stresses, biofilm reactors were operated at different temperatures (10 °C-35 °C) treating saline wastewater (salinity 3%). The results showed nitrogen removal efficiency was 98.46% at 30 °C and 60.85% at 10 °C, respectively. Both ammonia oxidizing archaea (AOA) and ammonia oxidizing bacteria (AOB) participated in nitrification. 94.9% of the overall ammonia oxidation was attributed to AOA at 10 °C, but only 48.2% of that was undertaken by AOA at 35 °C. AOA had a greater contribution at low temperature, which demonstrated that nitrogen removal pathway varied with temperature. Aerobic denitrification was more stable than anoxic denitrification. High-throughput sequencing showed Crenarchaeota was the dominant AOA (97.02-34.47%), cooperating with various heterotrophic AOB. Real-time PCR indicated that AOA was three orders of magnitude more abundant than AOB. AOA was more resistant to low temperature and high-saline stresses. Ammonia oxidizers had distinct responses to temperature change and showed diverse relationships at different temperatures.},
}
@article {pmid32633872,
year = {2020},
author = {Eichler, J},
title = {N-glycosylation in Archaea - New roles for an ancient post-translational modification.},
journal = {Molecular microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/mmi.14569},
pmid = {32633872},
issn = {1365-2958},
abstract = {Genome analysis points to N-glycosylation as being an almost universal post-translational modification in Archaea. Although such predictions have been confirmed in only a limited number of species, such studies are making it increasingly clear that the N-linked glycans which decorate archaeal glycoproteins present diversity in terms of both glycan composition and architecture far beyond what is seen in the other two domains of life. In addition to continuing to decipher pathways of N-glycosylation, recent efforts have revealed how Archaea exploit this variability in novel roles. In addition to encouraging glycoprotein synthesis, folding and assembly into properly functioning higher-ordered complexes, N-glycosylation also provides Archaea with a strategy to cope with changing environments. Archaea can also exploit the apparent species-specific nature of N-glycosylation for selectivity in mating, and hence to maintain species boundaries, and in other events where cell-selective interactions are required. At the same, addressing components of N-glycosylation pathways across archaeal phylogeny offers support for the concept of an archaeal origin for eukaryotes. In this MicroReview, these and other recent discoveries related to N-glycosylation in Archaea are considered.},
}
@article {pmid32631866,
year = {2020},
author = {Zou, D and Wan, R and Han, L and Xu, MN and Liu, Y and Liu, H and Kao, SJ and Li, M},
title = {Genomic Characteristics of a Novel Species of Ammonia-oxidizing Archaea from the Jiulong River Estuary.},
journal = {Applied and environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1128/AEM.00736-20},
pmid = {32631866},
issn = {1098-5336},
abstract = {Ammonia-oxidizing archaea (AOA) are ubiquitous in diverse ecosystems, and play a pivotal role in global nitrogen and carbon cycling. Although AOA diversity and distribution are widely studied mainly based on the amoA (alpha subunit of ammonia monooxygenase) genotypes, only limited investigations addressed the relationship between AOA genetic adaptation, metabolic features, and ecological niches, especially in estuaries. Here, we have described the AOA communities along the Jiulong River Estuary in Southern China. Nine high-quality AOA metagenome-assembled genomes (MAGs) were obtained by metagenomics. Five of the MAGs are proposed to constitute a new species, Ca Nitrosopumilus aestuariumsis sp. nov., based on the phylogenies of the 16S-23S rRNA genes and concatenated ribosomal proteins, as well as the average amino acid identity. Comparative genomic analysis revealed unique features of the new species, including a high number of genes related to diverse carbohydrate-active enzymes, phosphatases, heavy metal transport systems, flagellation, and chemotaxis. These genes may be crucial for AOA adaptation to the eutrophic and heavy metal-contaminated Jiulong River Estuary. The uncovered detailed genomic characteristics of the new estuarine AOA species highlights AOA contribution to ammonia oxidation in the Jiulong River Estuary.IMPORTANCE In this study, AOA communities along a river of Southern China were characterized and metagenome-assembled genomes (MAGs) of a novel AOA clade were also obtained. Based on the characterization of AOA genomes, this study suggested adaptation of the novel AOAs to estuarine environments, providing new information for ecology of estuarine AOA and nitrogen cycle in contaminated estuarine environments.},
}
@article {pmid32625030,
year = {2019},
author = {Pappenreiter, PA and Zwirtmayr, S and Mauerhofer, LM and Rittmann, SKR and Paulik, C},
title = {Development of a simultaneous bioreactor system for characterization of gas production kinetics of methanogenic archaea at high pressure.},
journal = {Engineering in life sciences},
volume = {19},
number = {7},
pages = {537-544},
pmid = {32625030},
issn = {1618-0240},
abstract = {Cultivation of methanogens under high pressure offers a great opportunity in biotechnological processes, one of which is the improvement of the gas-liquid transfer of substrate gases into the medium broth. This article describes a newly developed simultaneous bioreactor system consisting of four identical cultivation vessels suitable for investigation of microbial activity at pressures up to 50 bar and temperatures up to 145°C. Initial pressure studies at 10 and 50 bar of the autotrophic and hydrogenotrophic methanogens Methanothermobacter marburgensis, Methanobacterium palustre, and Methanobacterium thermaggregans were performed to evaluate the reproducibility of the system as well as to test the productivity of these strains. The strains were compared with respect to gas conversion (%), methane evolution rate (MER) (mmol L-1 h-1), turnover rate (h-1), and maximum conversion rate (kmin) (bar h-1). A pressure drop that can be explained by the reaction stoichiometry showed that all tested strains were active under pressurized conditions. Our study sheds light on the production kinetics of methanogenic strains under high-pressure conditions. In addition, the simultaneous bioreactor system is a suitable first step screening system for analyzing the substrate uptake and/or production kinetics of gas conversion and/or gas production processes for barophilic or barotolerant microbes.},
}
@article {pmid32608808,
year = {2020},
author = {Zhang, Y and Zuo, JE and Wang, SK and Alisa, S and Li, AJ and Li, LL},
title = {[Spatial Distribution of Nitrogen Metabolism Functional Genes of Eubacteria and Archaebacteria in Dianchi Lake].},
journal = {Huan jing ke xue= Huanjing kexue},
volume = {41},
number = {6},
pages = {2908-2917},
doi = {10.13227/j.hjkx.201909196},
pmid = {32608808},
issn = {0250-3301},
abstract = {Nitrogen metabolism plays an important role in the nitrogen cycle and transformation in Dianchi Lake. Not only do eukaryotes participate in nitrogen transformation but prokaryotes, as the main drivers of the nitrogen cycle, also play an extremely important role in the nitrogen cycle. Based on 16S rDNA high-throughput sequencing technology, 13 sites in Caohai and Waihai of Dianchi Lake were monitored, and PICRUSt function analysis method was adopted to analyze the microbial community diversity and key genes of nitrogen metabolism in Dianchi Lake. Bacteria belonging to 35 phyla and 427 genera were found in Dianchi Lake water and mainly included Proteobacteria and Bacteroidetes. Archaea had 14 phyla and 61 genera and mainly belonged to Euryarchaeota. The overall bacterial richness index of Dianchi Lake was higher than that of archaea, and the bacterial diversity index of Caohai was higher than that of Waihai. Functional prediction showed functional richness of bacteria and archaea. There were 35 KO pathways involved in nitrogen metabolism in bacteria, including key genes such as nitrogenous nitrate-reducing gene nirB, nitric oxide reductase gene norB in denitrification, and nitroreductase gene nasK. There were 23 KO pathways involved in nitrogen metabolism in archaea, involving nifH, nifK, and nifD nitrogenase genes in nitrogen fixation. The copy number of nitrogenase genes was significantly higher than that of other nitrogenase genes. The copy number of nitrogen-fixing genes of archaea was higher than that of bacteria, the nitrogen metabolism capacity of archaea in Caohai was higher than that in Waihai, and the potential of nitrogen-fixation of archaea in Dianchi Lake water was higher than that of bacteria. From the perspective of community structure and function prediction of bacteria and archaea, this study discussed the differences of nitrogen cycle in bacteria and archaea in different areas of Dianchi Lake and provided a decision basis for water environment management in Dianchi Lake.},
}
@article {pmid32602260,
year = {2020},
author = {Song, Y and Zhu, Z and Zhou, W and Zhang, YPJ},
title = {High-efficiency transformation of archaea by direct PCR products with its application to directed evolution of a thermostable enzyme.},
journal = {Microbial biotechnology},
volume = {},
number = {},
pages = {},
doi = {10.1111/1751-7915.13613},
pmid = {32602260},
issn = {1751-7915},
support = {2016-081//CAS Pioneer Hundred Talent Program/ ; 19JCYBJC24600//Natural Science Foundation of Tianjin City/ ; 21878324//National Natural Science Foundation of China/ ; 31800043//National Natural Science Foundation of China/ ; },
abstract = {Hyperthermophilic archaea with unique biochemical and physiological characteristics are important organisms for fundamental research of life science and have great potential for biotechnological applications. However, low transformation efficiency of foreign DNA molecules impedes developments in genetic modification tools and industrial applications. In this study, we applied prolonged overlap extension PCR (POE-PCR) to generate multimeric DNA molecules and then transformed them into two hyperthermophilic archaea, Thermococcus kodakarensis KOD1 and Pyrococcus yayanosii A1. This study was the first example to demonstrate the enhanced transformation efficiencies of POE-PCR products by a factor of approximately 100 for T. kodakarensis KOD1 and 8 for P. yayanosii A1, respectively, relative to circular shuttle plasmids. Furthermore, directed evolution of a modestly thermophilic enzyme, Methanothermococcus okinawensis 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR), was conducted to obtain more stable ones due to high transformation efficiency of T. kodakarensis (i.e. ~3 × 104 CFU per μg DNA). T. kodakarensis harbouring the most thermostable MoHMGR mutant can grow in the presence of a thermostable antibiotic simvastatin at 85°C and even higher temperatures. This high transformation efficiency technique could not only help develop more hyperthermophilic enzyme mutants via directed evolution but also simplify genetical modification of archaea, which could be novel hosts for industrial biotechnology.},
}
@article {pmid32580393,
year = {2020},
author = {Leoni, C and Volpicella, M and Fosso, B and Manzari, C and Piancone, E and Dileo, MCG and Arcadi, E and Yakimov, M and Pesole, G and Ceci, LR},
title = {A Differential Metabarcoding Approach to Describe Taxonomy Profiles of Bacteria and Archaea in the Saltern of Margherita di Savoia (Italy).},
journal = {Microorganisms},
volume = {8},
number = {6},
pages = {},
doi = {10.3390/microorganisms8060936},
pmid = {32580393},
issn = {2076-2607},
support = {634486//Horizon 2020/ ; 97/2018//Banca d'Italia/ ; },
abstract = {Microorganisms inhabiting saline environments are an interesting ecological model for the study of the adaptation of organisms to extreme living conditions and constitute a precious resource of enzymes and bioproducts for biotechnological applications. We analyzed the microbial communities in nine ponds with increasing salt concentrations (salinity range 4.9-36.0%) of the Saltern of Margherita di Savoia (Italy), the largest thalassohaline saltern in Europe. A deep-metabarcoding NGS procedure addressing separately the V5-V6 and V3-V4 hypervariable regions of the 16S rRNA gene of Bacteria and Archaea, respectively, and a CARD-FISH (catalyzed reporter deposition fluorescence in situ hybridization) analysis allowed us to profile the dynamics of microbial populations at the different salt concentrations. Both the domains were detected throughout the saltern, even if the low relative abundance of Archaea in the three ponds with the lowest salinities prevented the construction of the relative amplicon libraries. The highest cell counts were recorded at 14.5% salinity for Bacteria and at 24.1% salinity for Archaea. While Bacteria showed the greatest number of genera in the first ponds (salinity range 4.9-14.5%), archaeal genera were more numerous in the last ponds of the saltern (salinity 24.1-36.0%). Among prokaryotes, Salinibacter was the genus with the maximum abundance (~49% at 34.6% salinity). Other genera detected at high abundance were the archaeal Haloquadratum (~43% at 36.0% salinity) and Natronomonas (~18% at 13.1% salinity) and the bacterial "Candidatus Aquiluna" (~19% at 14.5% salinity). Interestingly, "Candidatus Aquiluna" had not been identified before in thalassohaline waters.},
}
@article {pmid32569776,
year = {2020},
author = {Coker, OO and Kai Wu, WK and Wong, SH and Sung, JJ and Yu, J},
title = {Altered Gut Archaea Composition and Interaction with Bacteria are Associated with Colorectal Cancer.},
journal = {Gastroenterology},
volume = {},
number = {},
pages = {},
doi = {10.1053/j.gastro.2020.06.042},
pmid = {32569776},
issn = {1528-0012},
abstract = {BACKGROUND &amp; AIMS: Changes in the intestinal microbiota have been associated with development and progression of colorectal cancer (CRC). Archaea are stable components of the microbiota, but little is known about their composition or contribution to colorectal carcinogenesis. We analyzed archaea in fecal microbiomes of 2 large cohorts of patients with CRC.<br><br>METHODS: We performed shotgun metagenomic analyses of fecal samples from 585 subjects (184 patients with CRC, 197 patients with adenomas, and 204 healthy individuals [controls]) from discovery (165 individuals) and validation (420 individuals) cohorts. Assignment of taxonomies was performed by exact k-mer alignment against an integrated microbial reference genome database.<br><br>RESULTS: Principal component analysis of archaeomes revealed distinct clusters in fecal samples from patients with CRC, patients with adenomas, and controls (P<.001), indicating an alteration in the composition of enteric archaea during tumorigenesis. Fecal samples from patients with CRC had significant enrichment of halophilic and depletion of methanogenic archaea. The halophilic Natrinema sp. J7-2 increased progressively in samples from controls, to patients with adenomas, to patients with CRC. Abundances of 9 archaea species that were enriched in fecal samples from patients with CRC distinguished them from controls with areas under the receiver operating characteristic curve of 0.82 in the discovery cohort and 0.83 in the validation cohort. An association between archaea and bacteria diversities was observed in fecal samples from controls but not from patients with CRC. Archaea that were enriched in fecal samples from patients with CRC had an extensive mutual association with bacteria that were enriched in the same samples, and exclusivity with bacteria that were lost from these samples.<br><br>CONCLUSIONS: Archaeomes of fecal samples from patients with CRC are characterized by enrichment of halophiles and depletion of methanogens. Studies are needed to determine whether associations between specific archaea and bacteria species in samples from patients with CRC contribute to or are a response to colorectal tumorigenesis.},
}
@article {pmid32546672,
year = {2020},
author = {Zhao, J and Meng, Y and Drewer, J and Skiba, UM and Prosser, JI and Gubry-Rangin, C},
title = {Differential Ecosystem Function Stability of Ammonia-Oxidizing Archaea and Bacteria following Short-Term Environmental Perturbation.},
journal = {mSystems},
volume = {5},
number = {3},
pages = {},
doi = {10.1128/mSystems.00309-20},
pmid = {32546672},
issn = {2379-5077},
abstract = {Rapidly expanding conversion of tropical forests to oil palm plantations in Southeast Asia leads to soil acidification following intensive nitrogen fertilization. Changes in soil pH are predicted to have an impact on archaeal ammonia-oxidizing archaea (AOA), ammonia-oxidizing bacteria (AOB), and complete (comammox) ammonia oxidizers and, consequently, on nitrification. It is therefore critical to determine whether the predicted effects of pH on ammonia oxidizers and nitrification activity apply in tropical soils subjected to various degrees of anthropogenic activity. This was investigated by experimental manipulation of pH in soil microcosms from a land-use gradient (forest, riparian, and oil palm soils). The nitrification rate was greater in forest soils with native neutral pH than in converted acidic oil palm soils. Ammonia oxidizer activity decreased following acidification of the forest soils but increased after liming of the oil palm soils, leading to a trend of a reversed net nitrification rate after pH modification. AOA and AOB nitrification activity was dependent on pH, but AOB were more sensitive to pH modification than AOA, which demonstrates a greater stability of AOA than AOB under conditions of short-term perturbation. In addition, these results predict AOB to be a good bioindicator of nitrification response following pH perturbation during land-use conversion. AOB and/or comammox species were active in all soils along the land-use gradient, even, unexpectedly, under acidic conditions, suggesting their adaptation to native acidic or acidified soils. The present study therefore provided evidence for limited stability of soil ammonia oxidizer activity following intensive anthropogenic activities, which likely aggravates the vulnerability of nitrogen cycle processes to environmental disturbance.IMPORTANCE Physiological and ecological studies have provided evidence for pH-driven niche specialization of ammonia oxidizers in terrestrial ecosystems. However, the functional stability of ammonia oxidizers following pH change has not been investigated, despite its importance in understanding the maintenance of ecosystem processes following environmental perturbation. This is particularly true after anthropogenic perturbation, such as the conversion of tropical forest to oil palm plantations. This study demonstrated a great impact of land-use conversion on nitrification, which is linked to changes in soil pH due to common agricultural practices (intensive fertilization). In addition, the different communities of ammonia oxidizers were differently affected by short-term pH perturbations, with implications for future land-use conversions but also for increased knowledge of associated global nitrous oxide emissions and current climate change concerns.},
}
@article {pmid32535177,
year = {2020},
author = {Di Giulio, M},
title = {The phylogenetic distribution of the glutaminyl-tRNA synthetase and Glu-tRNAGln amidotransferase in the fundamental lineages would imply that the ancestor of archaea, that of eukaryotes and LUCA were progenotes.},
journal = {Bio Systems},
volume = {},
number = {},
pages = {104174},
doi = {10.1016/j.biosystems.2020.104174},
pmid = {32535177},
issn = {1872-8324},
abstract = {The function of the glutaminyl-tRNA synthetase and Glu-tRNAGln amidotransferase might be related to the origin of the genetic code because, for example, glutaminyl-tRNA synthetase catalyses the fundamental reaction that makes the genetic code. If the evolutionary stage of the origin of these two enzymes could be unambiguously identified, then the genetic code should still have been originating at that particular evolutionary stage because the fundamental reaction that makes the code itself was still evidently evolving. This would result in that particular evolutionary moment being attributed to the evolutionary stage of the progenote because it would have a relationship between the genotype and the phenotype not yet fully realized because the genetic code was precisely still originating. I then analyzed the distribution of the glutaminyl-tRNA synthetase and Glu-tRNAGln aminodotrasferase in the main phyletic lineages. Since in some cases the origin of these two enzymes can be related to the evolutionary stages of ancestors of archaea and eukaryotes, this would indicate these ancestors as progenotes because at that evolutionary moment the genetic code was evidently still evolving, thus realizing the definition of progenote. The conclusion that the ancestor of archaea and that of eukaryotes were progenotes would imply that even the last universal common ancestor (LUCA) was a progenote because it appeared, on the tree of life, temporally before these ancestors.},
}
@article {pmid32534168,
year = {2020},
author = {Pinevich, AV},
title = {On the use of basic terms eukaryotic cell/eukaryotes/nucleated organisms, on evolutionary views challenged by the discovery of eukaryotic signatures in asgard archaea, and on a new taxon name for eukaryotes.},
journal = {Bio Systems},
volume = {},
number = {},
pages = {104178},
doi = {10.1016/j.biosystems.2020.104178},
pmid = {32534168},
issn = {1872-8324},
abstract = {The endosymbiosis theory most widely accepted variant surmises the engulfment of bacterial cell by archaeal cell. For decades, this scenario was reputed to be an unconfirmed hypothesis, and only recently it has obtained an indirect proof in Asgard archaea environmental DNA encoding eukaryotic signatures - actin cytoskeleton, small GTPases, and ESCRT complex. In view of growing interest to this aspect of the endosymbiosis theory, it seemed timely to revisit basic terms eukaryotic cell/eukaryotes/nucleated organisms. The article highlights inadequate applications of these terms, and seeks for their consistency with regard to phylogeny and taxonomy. Additionally, new name Caryosignifera is proposed for the archaeal phylum represented by: (1) several underexplored representatives of Asgard archaea manifested by above-mentioned DNA; (2) extant descendants of extinct engulfing archaea; (3) eukaryotic host cell lineages in modern nucleated organisms (protists, algae, plants, fungi, and animals).},
}
@article {pmid32527006,
year = {2020},
author = {Gryta, A and Frąc, M},
title = {Methodological Aspects of Multiplex Terminal Restriction Fragment Length Polymorphism-Technique to Describe the Genetic Diversity of Soil Bacteria, Archaea and Fungi.},
journal = {Sensors (Basel, Switzerland)},
volume = {20},
number = {11},
pages = {},
doi = {10.3390/s20113292},
pmid = {32527006},
issn = {1424-8220},
support = {2018/02/X/NZ9/00515//National Science Center/ ; BIOSTRATEG3/347464/5/NCBR/2017//The National Centre for Research and Development/ ; },
abstract = {The molecular fingerprinting methods used to evaluate soil microbial diversity could also be used as effective biosensors for the purposes of monitoring ecological soil status. The biodiversity of microorganisms is a relevant index of soil activity and there is a necessity to develop tools to generate reliable results for an emerging approach in the field of environmental control using microbial diversity biosensors. This work reports a method under development for determining soil microbial diversity using high efficiency Multiplex PCR-Terminal Restriction Fragment Length Polymorphism (M-T-RFLP) for the simultaneous detection of bacteria, archaea and fungi. Three different primer sets were used in the reaction and the analytical conditions were optimized. Optimal analytical conditions were achieved using 0.5 µM of primer for bacteria and 1 µM for archaea and fungi, 4 ng of soil DNA template, and HaeIII restriction enzyme. Comparative tests using the proposed analytical approach and a single analysis of each microorganism group were carried out to indicate that both genetic profiles were similar. The Jaccard similarity coefficient between single and multiplexing approach ranged from 0.773 to 0.850 for bacteria and fungi, and 0.208 to 0.905 for archaea. In conclusion, the multiplexing and pooling approaches significantly reduced the costs and time required to perform the analyses, while maintaining a proper effectiveness.},
}
@article {pmid32514073,
year = {2020},
author = {Murray, AE and Freudenstein, J and Gribaldo, S and Hatzenpichler, R and Hugenholtz, P and Kämpfer, P and Konstantinidis, KT and Lane, CE and Papke, RT and Parks, DH and Rossello-Mora, R and Stott, MB and Sutcliffe, IC and Thrash, JC and Venter, SN and Whitman, WB and Acinas, SG and Amann, RI and Anantharaman, K and Armengaud, J and Baker, BJ and Barco, RA and Bode, HB and Boyd, ES and Brady, CL and Carini, P and Chain, PSG and Colman, DR and DeAngelis, KM and de Los Rios, MA and Estrada-de Los Santos, P and Dunlap, CA and Eisen, JA and Emerson, D and Ettema, TJG and Eveillard, D and Girguis, PR and Hentschel, U and Hollibaugh, JT and Hug, LA and Inskeep, WP and Ivanova, EP and Klenk, HP and Li, WJ and Lloyd, KG and Löffler, FE and Makhalanyane, TP and Moser, DP and Nunoura, T and Palmer, M and Parro, V and Pedrós-Alió, C and Probst, AJ and Smits, THM and Steen, AD and Steenkamp, ET and Spang, A and Stewart, FJ and Tiedje, JM and Vandamme, P and Wagner, M and Wang, FP and Hedlund, BP and Reysenbach, AL},
title = {Roadmap for naming uncultivated Archaea and Bacteria.},
journal = {Nature microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41564-020-0733-x},
pmid = {32514073},
issn = {2058-5276},
support = {DEB-1841658//National Science Foundation (NSF)/ ; DEB-1841658//National Science Foundation (NSF)/ ; DEB-1841658//National Science Foundation (NSF)/ ; },
abstract = {The assembly of single-amplified genomes (SAGs) and metagenome-assembled genomes (MAGs) has led to a surge in genome-based discoveries of members affiliated with Archaea and Bacteria, bringing with it a need to develop guidelines for nomenclature of uncultivated microorganisms. The International Code of Nomenclature of Prokaryotes (ICNP) only recognizes cultures as 'type material', thereby preventing the naming of uncultivated organisms. In this Consensus Statement, we propose two potential paths to solve this nomenclatural conundrum. One option is the adoption of previously proposed modifications to the ICNP to recognize DNA sequences as acceptable type material; the other option creates a nomenclatural code for uncultivated Archaea and Bacteria that could eventually be merged with the ICNP in the future. Regardless of the path taken, we believe that action is needed now within the scientific community to develop consistent rules for nomenclature of uncultivated taxa in order to provide clarity and stability, and to effectively communicate microbial diversity.},
}
@article {pmid32507415,
year = {2020},
author = {Zhou, S and Xiang, H and Liu, JL},
title = {CTP synthase forms cytoophidia in archaea.},
journal = {Journal of genetics and genomics = Yi chuan xue bao},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.jgg.2020.03.004},
pmid = {32507415},
issn = {1673-8527},
abstract = {CTP synthase (CTPS) is an important metabolic enzyme that catalyzes the rate-limiting reaction of nucleotide CTP de novo synthesis. Since 2010, a series of studies have demonstrated that CTPS can form filamentous structures in bacteria and eukaryotes, which are termed cytoophidia. However, it is unknown whether cytoophidia exist in the third domain of life, archaea. Using Haloarcula hispanica as a model system, here we demonstrate that CTPS forms distinct intracellular compartments in archaea. Under stimulated emission depletion microscopy, we find that the structures of H. hispanica CTPS are elongated, similar to cytoophidia in bacteria and eukaryotes. When Haloarcula cells are cultured in low-salt medium, the occurrence of cytoophidia increases dramatically. In addition, treatment of H. hispanica with a glutamine analog or overexpression of CTPS can promote cytoophidium assembly. Our study reveals that CTPS can form cytoophidia in all three domains of life, suggesting that forming cytoophidia is an ancient property of CTPS.},
}
@article {pmid32503045,
year = {2020},
author = {},
title = {Corrigendum to: D-Galactose catabolism in archaea: Operation of the DeLey-Doudoroff pathway in Haloferax volcanii.},
journal = {FEMS microbiology letters},
volume = {367},
number = {11},
pages = {},
doi = {10.1093/femsle/fnaa069},
pmid = {32503045},
issn = {1574-6968},
}
@article {pmid32499624,
year = {2020},
author = {Tang, L},
title = {Taxonomy of Bacteria and Archaea.},
journal = {Nature methods},
volume = {17},
number = {6},
pages = {562},
doi = {10.1038/s41592-020-0863-3},
pmid = {32499624},
issn = {1548-7105},
}
@article {pmid32499102,
year = {2020},
author = {Peng, X and Mayo-Muñoz, D and Bhoobalan-Chitty, Y and Martínez-Álvarez, L},
title = {Anti-CRISPR Proteins in Archaea.},
journal = {Trends in microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.tim.2020.05.007},
pmid = {32499102},
issn = {1878-4380},
abstract = {Anti-CRISPR (Acr) proteins are natural inhibitors of CRISPR-Cas immune systems. To date, Acrs inhibiting types I, II, III, V, and VI CRISPR-Cas systems have been characterized. While most known Acrs are derived from bacterial phages and prophages, very few have been characterized in the domain Archaea, despite the nearly ubiquitous presence of CRISPR-Cas in archaeal cells. Here we summarize the discovery and characterization of the archaeal Acrs with the representatives encoded by a model archaeal virus, Sulfolobus islandicus rod-shaped virus 2 (SIRV2). AcrID1 inhibits subtype I-D CRISPR-Cas immunity through direct interaction with the large subunit Cas10d of the effector complex, and AcrIIIB1 inhibits subtype III-B CRISPR-Cas immunity through a mechanism interfering with middle/late gene targeting. Future development of efficient screening methods will be key to uncovering the diversity of archaeal Acrs.},
}
@article {pmid32449429,
year = {2020},
author = {Qi, L and Li, J and Jia, J and Yue, L and Dong, X},
title = {Comprehensive analysis of the pre-ribosomal RNA maturation pathway in a methanoarchaeon exposes the conserved circularization and linearization mode in archaea.},
journal = {RNA biology},
volume = {},
number = {},
pages = {},
doi = {10.1080/15476286.2020.1771946},
pmid = {32449429},
issn = {1555-8584},
abstract = {The ribosomal RNA (rRNA) genes are generally organized as an operon and cotranscribed into a polycistronic precursor; therefore, processing and maturation of pre-rRNAs are essential for ribosome biogenesis. However, rRNA maturation pathways of archaea, particularly of methanoarchaea, are scarcely known. Here, we thoroughly elucidated the maturation pathway of the rRNA operon (16S-tRNAAla-23S-tRNACys-5S) in Methanolobus psychrophilus, one representative of methanoarchaea. Enzymatic assay demonstrated that EndA, a tRNA splicing endoribonuclease, cleaved bulge-helix-bulge (BHB) motifs buried in the processing stems of pre-16S and pre-23S rRNAs. Northern blot and quantitative PCR detected splicing-coupled circularization of pre-16S and pre-23S rRNAs, which accounted for 2% and 12% of the corresponding rRNAs, respectively. Importantly, endoribonuclease Nob1 was determined to linearize circular pre-16S rRNA at the mature 3' end so to expose the anti-Shine-Dalgarno sequence, while circular pre-23S rRNA was linearized at the mature 5' end by an unknown endoribonuclease. The resultant 5' and 3' extension in linearized pre-16S and pre-23S rRNAs were finally matured through 5'-3' and 3'-5' exoribonucleolytic trimming, respectively. Additionally, a novel processing pathway of endoribonucleolysis coupled with exoribonucleolysis was identified for the pre-5S rRNA maturation in this methanogen, which could be also conserved in most methanogenic euryarchaea. Based on evaluating the phylogenetic conservation of the key elements that are involved in circularization and linearization of pre-rRNA maturation, we predict that the rRNA maturation mode revealed here could be prevalent among archaea.},
}
@article {pmid32448158,
year = {2020},
author = {Eckert, I and Weinberg, Z},
title = {Discovery of 20 novel ribosomal leader candidates in bacteria and archaea.},
journal = {BMC microbiology},
volume = {20},
number = {1},
pages = {130},
doi = {10.1186/s12866-020-01823-6},
pmid = {32448158},
issn = {1471-2180},
support = {WE6322/1-1//Deutsche Forschungsgemeinschaft/ ; },
abstract = {BACKGROUND: RNAs perform many functions in addition to supplying coding templates, such as binding proteins. RNA-protein interactions are important in multiple processes in all domains of life, and the discovery of additional protein-binding RNAs expands the scope for studying such interactions. To find such RNAs, we exploited a form of ribosomal regulation. Ribosome biosynthesis must be tightly regulated to ensure that concentrations of rRNAs and ribosomal proteins (r-proteins) match. One regulatory mechanism is a ribosomal leader (r-leader), which is a domain in the 5' UTR of an mRNA whose genes encode r-proteins. When the concentration of one of these r-proteins is high, the protein binds the r-leader in its own mRNA, reducing gene expression and thus protein concentrations. To date, 35 types of r-leaders have been validated or predicted.<br><br>RESULTS: By analyzing additional conserved RNA structures on a multi-genome scale, we identified 20 novel r-leader structures. Surprisingly, these included new r-leaders in the highly studied organisms Escherichia coli and Bacillus subtilis. Our results reveal several cases where multiple unrelated RNA structures likely bind the same r-protein ligand, and uncover previously unknown r-protein ligands. Each r-leader consistently occurs upstream of r-protein genes, suggesting a regulatory function. That the predicted r-leaders function as RNAs is supported by evolutionary correlations in the nucleotide sequences that are characteristic of a conserved RNA secondary structure. The r-leader predictions are also consistent with the locations of experimentally determined transcription start sites.<br><br>CONCLUSIONS: This work increases the number of known or predicted r-leader structures by more than 50%, providing additional opportunities to study structural and evolutionary aspects of RNA-protein interactions. These results provide a starting point for detailed experimental studies.},
}
@article {pmid32442771,
year = {2020},
author = {Shi, LD and Lv, PL and Wang, M and Lai, CY and Zhao, HP},
title = {A mixed consortium of methanotrophic archaea and bacteria boosts methane-dependent selenate reduction.},
journal = {The Science of the total environment},
volume = {732},
number = {},
pages = {139310},
doi = {10.1016/j.scitotenv.2020.139310},
pmid = {32442771},
issn = {1879-1026},
abstract = {Though methane-based selenate reduction has been reported, neither the selenate load nor the removal rate could satisfy practical applications, thus limiting this technique to bio-remediate selenate pollution. In the present study, using a membrane biofilm batch reactor (MBBR), we successfully enriched a consortium performing methane-dependent selenate reduction, with enhanced reduction rates from 16.1 to 28.9 μM-day-1 under a comparable Se concentration to industrial wastewaters (i.e., ~500 μM). During active reduction, 16S rRNA gene copies of Archaea and Bacteria were both increased more than one order of magnitude. Clone library construction and high-throughput sequencing indicated that Methanosarcina and Methylocystis were the only methane-oxidizing microorganisms. The presence of 20 mM bromoethanesulphonate or 0.15 mM acetylene both significantly, but not completely, inhibited methane-dependent selenate reduction, indicating the concurrent contributions of methanotrophic archaea and bacteria. Fluorescence in situ hybridization (FISH) revealed that archaea directly adhered to the surface of the membrane while bacteria were in the outer layer, together forming the mature biofilm. This study highlights the crucial role of both methanotrophic archaea and bacteria in methane-dependent selenate reduction, and lays foundations in applying methane to bio-remediate practical selenate pollution.},
}
@article {pmid32440868,
year = {2020},
author = {Yang, D and Xiao, X and He, N and Zhu, W and Liu, M and Xie, G},
title = {Effects of reducing chemical fertilizer combined with organic amendments on ammonia-oxidizing bacteria and archaea communities in a low-fertility red paddy field.},
journal = {Environmental science and pollution research international},
volume = {},
number = {},
pages = {},
doi = {10.1007/s11356-020-09120-5},
pmid = {32440868},
issn = {1614-7499},
support = {2016YFD0201200//the National Key Research and Development Program of China/ ; },
abstract = {Ammonia oxidation process in soil has a great contribution to the emission of nitrous oxide, which is a hot issue in the study of N cycle of rice field ecosystem. Organic amendments which partially substitute chemical nitrogen fertilizer are widely adopted to optimizing N management and reduce the use of chemical nitrogen fertilizers in the paddy ecosystem, but their long-term effects on ammonia-oxidizing archaea (AOA) and bacteria (AOB) were not well understood. Thus, based on a 6-year field trial that comprised four fertilization strategies (CF, chemical fertilizer; PM, pig manure substituting for 20% chemical N; BF, biogas slurry substituting for 20% chemical N; and GM, milk vetch substituting for 20% chemical N) and no N fertilizer application as CK, the abundance and community structure of ammonia oxidizers were examined by using qPCR and Illumina Miseq sequencing approaches based on the functional marker genes (amoA) in a low-fertility paddy field. The results revealed that 6 years of organic-substitute fertilization significantly increased AOA abundance in comparison with NF and CF. However, only CF and PM had a higher AOB abundance than those in NF and no significant difference between CF and organic-substitute treatments was observed. Both AOA and AOB were significantly correlated with soil potential nitrification rate (PNR). Moreover, organic-substitute treatments showed the evident changes in the AOA community, while little were observed in the AOB community. Soil pH was the main predictor for AOA abundance, while NH4+-N and NO3--N were the main predictors for AOB abundance. This study suggests that both AOA and AOB were jointly contributed to the variation of soil potential nitrification rate, while the AOA community was shown to be more responsive to organic-substitute fertilization strategies than AOB in the tested soils.},
}
@article {pmid32430468,
year = {2020},
author = {Lu, Z and Fu, T and Li, T and Liu, Y and Zhang, S and Li, J and Dai, J and Koonin, EV and Li, G and Chu, H and Li, M},
title = {Coevolution of Eukaryote-like Vps4 and ESCRT-III Subunits in the Asgard Archaea.},
journal = {mBio},
volume = {11},
number = {3},
pages = {},
doi = {10.1128/mBio.00417-20},
pmid = {32430468},
issn = {2150-7511},
abstract = {The emergence of the endomembrane system is a key step in the evolution of cellular complexity during eukaryogenesis. The endosomal sorting complex required for transport (ESCRT) machinery is essential and required for the endomembrane system functions in eukaryotic cells. Recently, genes encoding eukaryote-like ESCRT protein components have been identified in the genomes of Asgard archaea, a newly proposed archaeal superphylum that is thought to include the closest extant prokaryotic relatives of eukaryotes. However, structural and functional features of Asgard ESCRT remain uncharacterized. Here, we show that Vps4, Vps2/24/46, and Vps20/32/60, the core functional components of the Asgard ESCRT, coevolved eukaryote-like structural and functional features. Phylogenetic analysis shows that Asgard Vps4, Vps2/24/46, and Vps20/32/60 are closely related to their eukaryotic counterparts. Molecular dynamics simulation and biochemical assays indicate that Asgard Vps4 contains a eukaryote-like microtubule-interacting and transport (MIT) domain that binds the distinct type 1 MIT-interacting motif and type 2 MIT-interacting motif in Vps2/24/46 and Vps20/32/60, respectively. The Asgard Vps4 partly, but much more efficiently than homologs from other archaea, complements the vps4 null mutant of Saccharomyces cerevisiae, further supporting the functional similarity between the membrane remodeling machineries of Asgard archaea and eukaryotes. Thus, this work provides evidence that the ESCRT complexes from Asgard archaea and eukaryotes are evolutionarily related and functionally similar. Thus, despite the apparent absence of endomembranes in Asgard archaea, the eukaryotic ESCRT seems to have been directly inherited from an Asgard ancestor, to become a key component of the emerging endomembrane system.IMPORTANCE The discovery of Asgard archaea has changed the existing ideas on the origins of eukaryotes. Researchers propose that eukaryotic cells evolved from Asgard archaea. This hypothesis partly stems from the presence of multiple eukaryotic signature proteins in Asgard archaea, including homologs of ESCRT proteins that are essential components of the endomembrane system in eukaryotes. However, structural and functional features of Asgard ESCRT remain unknown. Our study provides evidence that Asgard ESCRT is functionally comparable to the eukaryotic counterparts, suggesting that despite the apparent absence of endomembranes in archaea, eukaryotic ESCRT was inherited from an Asgard archaeal ancestor, alongside the emergence of endomembrane system during eukaryogenesis.},
}
@article {pmid32427979,
year = {2020},
author = {Baker, BJ and De Anda, V and Seitz, KW and Dombrowski, N and Santoro, AE and Lloyd, KG},
title = {Author Correction: Diversity, ecology and evolution of Archaea.},
journal = {Nature microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41564-020-0741-x},
pmid = {32427979},
issn = {2058-5276},
abstract = {An amendment to this paper has been published and can be accessed via a link at the top of the paper.},
}
@article {pmid32426487,
year = {2020},
author = {Meador, TB and Schoffelen, N and Ferdelman, TG and Rebello, O and Khachikyan, A and Könneke, M},
title = {Carbon recycling efficiency and phosphate turnover by marine nitrifying archaea.},
journal = {Science advances},
volume = {6},
number = {19},
pages = {eaba1799},
doi = {10.1126/sciadv.aba1799},
pmid = {32426487},
issn = {2375-2548},
abstract = {Thaumarchaeotal nitrifiers are among the most abundant organisms in the ocean, but still unknown is the carbon (C) yield from nitrification and the coupling of these fluxes to phosphorus (P) turnover and release of metabolites from the cell. Using a dual radiotracer approach, we found that Nitrosopumilus maritimus fixed roughly 0.3 mol C, assimilated 2 mmol P, and released ca. 10-2 mol C and 10-5 mol P as dissolved organics (DOC and DOP) per mole ammonia respired. Phosphate turnover may influence assimilation fluxes by nitrifiers in the euphotic zone, which parallel those of the dark ocean. Collectively, marine nitrifiers assimilate up to 2 Pg C year-1 and 0.05 Pg P year-1 and thereby recycle roughly 5% of mineralized C and P into marine biomass. Release of roughly 50 Tg DOC and 0.2 Tg DOP by thaumarchaea each year represents a small but fresh input of reduced substrates throughout the ocean.},
}
@article {pmid32423947,
year = {2020},
author = {Takemata, N and Bell, SD},
title = {Emerging views of genome organization in Archaea.},
journal = {Journal of cell science},
volume = {133},
number = {10},
pages = {},
doi = {10.1242/jcs.243782},
pmid = {32423947},
issn = {1477-9137},
abstract = {Over the past decade, advances in methodologies for the determination of chromosome conformation have provided remarkable insight into the local and higher-order organization of bacterial and eukaryotic chromosomes. Locally folded domains are found in both bacterial and eukaryotic genomes, although they vary in size. Importantly, genomes of metazoans also possess higher-order organization into A- and B-type compartments, regions of transcriptionally active and inactive chromatin, respectively. Until recently, nothing was known about the organization of genomes of organisms in the third domain of life - the archaea. However, despite archaea possessing simple circular genomes that are morphologically reminiscent of those seen in many bacteria, a recent study of archaea of the genus Sulfolobus has revealed that it organizes its genome into large-scale domains. These domains further interact to form defined A- and B-type compartments. The interplay of transcription and localization of a novel structural maintenance of chromosomes (SMC) superfamily protein, termed coalescin, defines compartment identity. In this Review, we discuss the mechanistic and evolutionary implications of these findings.},
}
@article {pmid32422160,
year = {2020},
author = {Lekontseva, N and Mikhailina, A and Fando, M and Kravchenko, O and Balobanov, V and Tishchenko, S and Nikulin, A},
title = {Crystal structures and RNA-binding properties of Lsm proteins from archaea Sulfolobus acidocaldarius and Methanococcus vannielii: Similarity and difference of the U-binding mode.},
journal = {Biochimie},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.biochi.2020.05.001},
pmid = {32422160},
issn = {1638-6183},
abstract = {Sm and Sm-like (Lsm) proteins are considered as an evolutionary conserved family involved in RNA metabolism in organisms from bacteria and archaea to human. Currently, the function of Sm-like archaeal proteins (SmAP) is not well understood. Here, we report the crystal structures of SmAP proteins from Sulfolobus acidocaldarius and Methanococcus vannielii and a comparative analysis of their RNA-binding sites. Our data show that these SmAPs have only a uridine-specific RNA-binding site, unlike their bacterial homolog Hfq, which has three different RNA-binding sites. Moreover, variations in the amino acid composition of the U-binding sites of the two SmAPs lead to a difference in protein affinity for oligo(U) RNA. Surface plasmon resonance data and nucleotide-binding analysis confirm the high affinity of SmAPs for uridine nucleotides and oligo(U) RNA and the reduced affinity for adenines, guanines, cytidines and corresponding oligo-RNAs. In addition, we demonstrate that MvaSmAP1 and SacSmAP2 are capable of melting an RNA hairpin and, apparently, promote its interaction with complementary RNA.},
}
@article {pmid32382758,
year = {2020},
author = {Gelsinger, DR and Dallon, E and Reddy, R and Mohammad, F and Buskirk, AR and DiRuggiero, J},
title = {Ribosome profiling in archaea reveals leaderless translation, novel translational initiation sites, and ribosome pausing at single codon resolution.},
journal = {Nucleic acids research},
volume = {},
number = {},
pages = {},
doi = {10.1093/nar/gkaa304},
pmid = {32382758},
issn = {1362-4962},
abstract = {High-throughput methods, such as ribosome profiling, have revealed the complexity of translation regulation in Bacteria and Eukarya with large-scale effects on cellular functions. In contrast, the translational landscape in Archaea remains mostly unexplored. Here, we developed ribosome profiling in a model archaeon, Haloferax volcanii, elucidating, for the first time, the translational landscape of a representative of the third domain of life. We determined the ribosome footprint of H. volcanii to be comparable in size to that of the Eukarya. We linked footprint lengths to initiating and elongating states of the ribosome on leadered transcripts, operons, and on leaderless transcripts, the latter representing 70% of H. volcanii transcriptome. We manipulated ribosome activity with translation inhibitors to reveal ribosome pausing at specific codons. Lastly, we found that the drug harringtonine arrested ribosomes at initiation sites in this archaeon. This drug treatment allowed us to confirm known translation initiation sites and also reveal putative novel initiation sites in intergenic regions and within genes. Ribosome profiling revealed an uncharacterized complexity of translation in this archaeon with bacteria-like, eukarya-like, and potentially novel translation mechanisms. These mechanisms are likely to be functionally essential and to contribute to an expanded proteome with regulatory roles in gene expression.},
}
@article {pmid32380716,
year = {2020},
author = {Rawat, M and Maupin-Furlow, JA},
title = {Redox and Thiols in Archaea.},
journal = {Antioxidants (Basel, Switzerland)},
volume = {9},
number = {5},
pages = {},
doi = {10.3390/antiox9050381},
pmid = {32380716},
issn = {2076-3921},
support = {SC3GM-100855-03/NH/NIH HHS/United States ; MCB1244611//National Science Foundation/ ; DE-FG02-05ER15650//U.S. Department of Energy/ ; R01 GM57498/NH/NIH HHS/United States ; MCB-1642283//National Science Foundation/ ; },
abstract = {Low molecular weight (LMW) thiols have many functions in bacteria and eukarya, ranging from redox homeostasis to acting as cofactors in numerous reactions, including detoxification of xenobiotic compounds. The LMW thiol, glutathione (GSH), is found in eukaryotes and many species of bacteria. Analogues of GSH include the structurally different LMW thiols: bacillithiol, mycothiol, ergothioneine, and coenzyme A. Many advances have been made in understanding the diverse and multiple functions of GSH and GSH analogues in bacteria but much less is known about distribution and functions of GSH and its analogues in archaea, which constitute the third domain of life, occupying many niches, including those in extreme environments. Archaea are able to use many energy sources and have many unique metabolic reactions and as a result are major contributors to geochemical cycles. As LMW thiols are major players in cells, this review explores the distribution of thiols and their biochemistry in archaea.},
}
@article {pmid32375092,
year = {2020},
author = {Li, Y and Fan, C and Wang, L and Wang, L and Zhang, W and Zhang, H and Niu, L},
title = {Interaction type of tetrabromobisphenol A and copper manipulates ammonia-oxidizing archaea and bacteria communities in co-contaminated river sediments.},
journal = {Environmental pollution (Barking, Essex : 1987)},
volume = {264},
number = {},
pages = {114671},
doi = {10.1016/j.envpol.2020.114671},
pmid = {32375092},
issn = {1873-6424},
abstract = {The combined contamination of brominated flame retardants (BFRs) and heavy metals in electronic waste (e-waste) recycling and disposal areas has been a serious concern owing to their environmental persistence and chronic toxicities. Ammonia oxidizers, e.g., ammonia-oxidizing archaea (AOA) and bacteria (AOB) play essential roles in nitrogen cycling and can serve as ideal indicators that reflect the changes in sediment health in response to environmental variables. There is currently very little information available on the combined toxic effects of BFRs and heavy metals on AOA and AOB communities. In this study, two typical e-waste pollutants, tetrabromobisphenol A (TBBPA) and copper (Cu), were selected as target contaminants to investigate the individual and combined effects of both pollutants on AOA and AOB communities in river sediments. Respective treatments of TBBPA (1, 10, and 20 mg/kg wet weight), Cu (100 mg/kg wet weight) and their combined treatments (weight ratios of 1:100, 1:10, and 1:5) were performed in laboratory experiments. High-throughput sequencing was applied to explore the response of ammonia oxidizers to TBBPA and Cu. The interaction types of TBBPA and Cu were calculated by the directional classification system to reveal the individual and combined toxicities of both contaminants to the ammonia oxidizers. On days 15 and 30, the dominant interaction type of TBBPA and Cu was synergistic (62.50%), and the combined contamination exacted selective pressure and inhibition on the AOB and AOA communities. On days 45 and 90, the interaction type shifted to be antagonistic (83.33%), with both the AOB and AOA communities gradually reaching stable population equilibria. The alteration of the interaction type is attributed to the elevated TBBPA/Cu tolerance as the incubation time increased. This study disclosed the interaction types of TBBPA and Cu in contaminated river sediments, and revealed that the combined effect could potentially manipulate AOB and AOA communities.},
}
@article {pmid32372550,
year = {2020},
author = {Juottonen, H and Fontaine, L and Wurzbacher, C and Drakare, S and Peura, S and Eiler, A},
title = {Archaea in boreal Swedish lakes are diverse, dominated by Woesearchaeota and follow deterministic community assembly.},
journal = {Environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/1462-2920.15058},
pmid = {32372550},
issn = {1462-2920},
abstract = {Despite their key role in biogeochemical processes, particularly the methane cycle, archaea are widely underrepresented in molecular surveys because of their lower abundance compared to bacteria and eukaryotes. Here, we use parallel high-resolution small subunit rRNA gene sequencing to explore archaeal diversity in 109 Swedish lakes and correlate archaeal community assembly mechanisms to large-scale latitudinal, climatic (nemoral to arctic), and nutrient (oligotrophic to eutrophic) gradients. Sequencing with universal primers showed the contribution of archaea was on average 0.8% but increased up to 1.5% of the three domains in forest lakes. Archaea-specific sequencing revealed that freshwater archaeal diversity could be partly explained by lake variables associated with nutrient status. Combined with deterministic co-occurrence patterns this finding suggests that ecological drift is overridden by environmental sorting, as well as other deterministic processes such as biogeographic and evolutionary history, leading to lake-specific archaeal biodiversity. Acetoclastic, hydrogenotrophic and methylotrophic methanogens as well as ammonia-oxidizing archaea were frequently detected across the lakes. Archaea-specific sequencing also revealed representatives of Woesearchaeota and other phyla of the DPANN superphylum. This study adds to our understanding of the ecological range of key archaea in freshwaters and links these taxa to hypotheses about processes governing biogeochemical cycles in lakes.},
}
@article {pmid32371309,
year = {2020},
author = {Xie, F and Ma, A and Zhou, H and Liang, Y and Yin, J and Ma, K and Zhuang, X and Zhuang, G},
title = {Niche differentiation of denitrifying anaerobic methane oxidizing bacteria and archaea leads to effective methane filtration in a Tibetan alpine wetland.},
journal = {Environment international},
volume = {140},
number = {},
pages = {105764},
doi = {10.1016/j.envint.2020.105764},
pmid = {32371309},
issn = {1873-6750},
abstract = {Denitrifying anaerobic methane oxidation (DAMO) is a vital methane sink in wetlands. However, the interactions and niche partitioning of DAMO bacteria and archaea in freshwater wetland soils, in addition to the interactions among microorganisms that couple methane and nitrogen cycling is still unclear, despite that these factors may govern the fate of methane and nitrogen in wetlands. Here, we evaluated the vertical distribution of DAMO bacteria and archaea in soil layers along with the potential interactions among populations in the methane-coupled nitrogen cycling microbial community of Tibetan freshwater wetlands. A combination of molecular biology, stable isotope tracer technology, and microbial bioinformatics was used to evaluate these interrelated dynamics. The abundances and potential methane oxidation rates indicated that DAMO bacteria and archaea differentially occupy surface and subsurface soil layers, respectively. The inferred interactions between DAMO bacteria and nitrogen cycling microorganisms within their communities are complex, DAMO bacteria apparently achieve an advantage in the highly competitive environment of surface soils layers and occupy a specific niche in those environments. Conversely, the apparent relationships between DAMO archaea and nitrogen cycling microorganisms are relatively simple, wherein high levels of cooperation are inferred between DAMO archaea and nitrate-producing organisms in subsurface soils layers. These results suggest that the vertical distribution patterns of DAMO bacteria and archaea enable them to play significant roles in the methane oxidation activity of different soil layers and collectively form an effective methane filtration consortium.},
}
@article {pmid32367670,
year = {2020},
author = {Wang, Y and Wegener, G and Ruff, SE and Wang, F},
title = {Methyl/alkyl-coenzyme M reductase-based anaerobic alkane oxidation in archaea.},
journal = {Environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/1462-2920.15057},
pmid = {32367670},
issn = {1462-2920},
abstract = {Methyl-coenzyme M reductase (MCR) has been originally identified to catalyze the final step of the methanogenesis pathway. About 20 years ago anaerobic methane-oxidizing archaea (ANME) were discovered that use MCR enzymes to activate methane. ANME thrive at the thermodynamic limit of life, are slow-growing, and in most cases form syntrophic consortia with sulfate-reducing bacteria. Recently, archaea that have the ability to anaerobically oxidize non-methane multi-carbon alkanes such as ethane and n-butane were described in both, enrichment cultures and environmental samples. These anaerobic multi-carbon alkane-oxidizing archaea (ANKA) use enzymes homologous to MCR named alkyl-coenzyme M reductase (ACR). Here we review the recent progresses on the diversity, distribution and functioning of both ANME and ANKA by presenting a detailed MCR/ACR-based phylogeny, compare their metabolic pathways, and discuss the gaps in our knowledge of physiology of these organisms. To improve our understanding of alkane oxidation in archaea, we identified three directions for future research: i) expanding cultivation attempts to validate omics-based metabolic models of yet-uncultured organisms, ii) performing biochemical and structural analyses of key enzymes to understand thermodynamic and steric constraints, iii) investigating evolution of anaerobic alkane metabolisms and their impact on biogeochemical cycles.},
}
@article {pmid32367054,
year = {2020},
author = {Baker, BJ and De Anda, V and Seitz, KW and Dombrowski, N and Santoro, AE and Lloyd, KG},
title = {Diversity, ecology and evolution of Archaea.},
journal = {Nature microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41564-020-0715-z},
pmid = {32367054},
issn = {2058-5276},
support = {1737298//National Science Foundation (NSF)/ ; 404586//Simons Foundation/ ; },
abstract = {Compared to bacteria, our knowledge of archaeal biology is limited. Historically, microbiologists have mostly relied on culturing and single-gene diversity surveys to understand Archaea in nature. However, only six of the 27 currently proposed archaeal phyla have cultured representatives. Advances in genomic sequencing and computational approaches are revolutionizing our understanding of Archaea. The recovery of genomes belonging to uncultured groups from the environment has resulted in the description of several new phyla, many of which are globally distributed and are among the predominant organisms on the planet. In this Review, we discuss how these genomes, together with long-term enrichment studies and elegant in situ measurements, are providing insights into the metabolic capabilities of the Archaea. We also debate how such studies reveal how important Archaea are in mediating an array of ecological processes, including global carbon and nutrient cycles, and how this increase in archaeal diversity has expanded our view of the tree of life and early archaeal evolution, and has provided new insights into the origin of eukaryotes.},
}
@article {pmid32345641,
year = {2020},
author = {DeWerff, SJ and Bautista, MA and Pauly, M and Zhang, C and Whitaker, RJ},
title = {Killer Archaea: Virus-Mediated Antagonism to CRISPR-Immune Populations Results in Emergent Virus-Host Mutualism.},
journal = {mBio},
volume = {11},
number = {2},
pages = {},
doi = {10.1128/mBio.00404-20},
pmid = {32345641},
issn = {2150-7511},
abstract = {Theory, simulation, and experimental evolution demonstrate that diversified CRISPR-Cas immunity to lytic viruses can lead to stochastic virus extinction due to a limited number of susceptible hosts available to each potential new protospacer escape mutation. Under such conditions, theory predicts that to evade extinction, viruses evolve toward decreased virulence and promote vertical transmission and persistence in infected hosts. To better understand the evolution of host-virus interactions in microbial populations with active CRISPR-Cas immunity, we studied the interaction between CRISPR-immune Sulfolobus islandicus cells and immune-deficient strains that are infected by the chronic virus SSV9. We demonstrate that Sulfolobus islandicus cells infected with SSV9, and with other related SSVs, kill uninfected, immune strains through an antagonistic mechanism that is a protein and is independent of infectious virus. Cells that are infected with SSV9 are protected from killing and persist in the population. We hypothesize that this infection acts as a form of mutualism between the host and the virus by removing competitors in the population and ensuring continued vertical transmission of the virus within populations with diversified CRISPR-Cas immunity.IMPORTANCE Multiple studies, especially those focusing on the role of lytic viruses in key model systems, have shown the importance of viruses in shaping microbial populations. However, it has become increasingly clear that viruses with a long host-virus interaction, such as those with a chronic lifestyle, can be important drivers of evolution and have large impacts on host ecology. In this work, we describe one such interaction with the acidic crenarchaeon Sulfolobus islandicus and its chronic virus Sulfolobus spindle-shaped virus 9. Our work expands the view in which this symbiosis between host and virus evolved, describing a killing phenotype which we hypothesize has evolved in part due to the high prevalence and diversity of CRISPR-Cas immunity seen in natural populations. We explore the implications of this phenotype in population dynamics and host ecology, as well as the implications of mutualism between this virus-host pair.},
}
@article {pmid32341564,
year = {2020},
author = {Parks, DH and Chuvochina, M and Chaumeil, PA and Rinke, C and Mussig, AJ and Hugenholtz, P},
title = {A complete domain-to-species taxonomy for Bacteria and Archaea.},
journal = {Nature biotechnology},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41587-020-0501-8},
pmid = {32341564},
issn = {1546-1696},
abstract = {The Genome Taxonomy Database is a phylogenetically consistent, genome-based taxonomy that provides rank-normalized classifications for ~150,000 bacterial and archaeal genomes from domain to genus. However, almost 40% of the genomes in the Genome Taxonomy Database lack a species name. We address this limitation by using commonly accepted average nucleotide identity criteria to set bounds on species and propose species clusters that encompass all publicly available bacterial and archaeal genomes. Unlike previous average nucleotide identity studies, we chose a single representative genome to serve as the effective nomenclatural 'type' defining each species. Of the 24,706 proposed species clusters, 8,792 are based on published names. We assigned placeholder names to the remaining 15,914 species clusters to provide names to the growing number of genomes from uncultivated species. This resource provides a complete domain-to-species taxonomic framework for bacterial and archaeal genomes, which will facilitate research on uncultivated species and improve communication of scientific results.},
}
@article {pmid32317322,
year = {2020},
author = {Hahn, CJ and Laso-Pérez, R and Vulcano, F and Vaziourakis, KM and Stokke, R and Steen, IH and Teske, A and Boetius, A and Liebeke, M and Amann, R and Knittel, K and Wegener, G},
title = {&quot;Candidatus Ethanoperedens,&quot; a Thermophilic Genus of Archaea Mediating the Anaerobic Oxidation of Ethane.},
journal = {mBio},
volume = {11},
number = {2},
pages = {},
doi = {10.1128/mBio.00600-20},
pmid = {32317322},
issn = {2150-7511},
abstract = {Cold seeps and hydrothermal vents deliver large amounts of methane and other gaseous alkanes into marine surface sediments. Consortia of archaea and partner bacteria thrive on the oxidation of these alkanes and its coupling to sulfate reduction. The inherently slow growth of the involved organisms and the lack of pure cultures have impeded the understanding of the molecular mechanisms of archaeal alkane degradation. Here, using hydrothermal sediments of the Guaymas Basin (Gulf of California) and ethane as the substrate, we cultured microbial consortia of a novel anaerobic ethane oxidizer, &quot;Candidatus Ethanoperedens thermophilum&quot; (GoM-Arc1 clade), and its partner bacterium &quot;Candidatus Desulfofervidus auxilii,&quot; previously known from methane-oxidizing consortia. The sulfate reduction activity of the culture doubled within one week, indicating a much faster growth than in any other alkane-oxidizing archaea described before. The dominance of a single archaeal phylotype in this culture allowed retrieval of a closed genome of &quot;Ca. Ethanoperedens,&quot; a sister genus of the recently reported ethane oxidizer &quot;Candidatus Argoarchaeum.&quot; The metagenome-assembled genome of &quot;Ca. Ethanoperedens&quot; encoded a complete methanogenesis pathway including a methyl-coenzyme M reductase (MCR) that is highly divergent from those of methanogens and methanotrophs. Combined substrate and metabolite analysis showed ethane as the sole growth substrate and production of ethyl-coenzyme M as the activation product. Stable isotope probing demonstrated that the enzymatic mechanism of ethane oxidation in &quot;Ca. Ethanoperedens&quot; is fully reversible; thus, its enzymatic machinery has potential for the biotechnological development of microbial ethane production from carbon dioxide.IMPORTANCE In the seabed, gaseous alkanes are oxidized by syntrophic microbial consortia that thereby reduce fluxes of these compounds into the water column. Because of the immense quantities of seabed alkane fluxes, these consortia are key catalysts of the global carbon cycle. Due to their obligate syntrophic lifestyle, the physiology of alkane-degrading archaea remains poorly understood. We have now cultivated a thermophilic, relatively fast-growing ethane oxidizer in partnership with a sulfate-reducing bacterium known to aid in methane oxidation and have retrieved the first complete genome of a short-chain alkane-degrading archaeon. This will greatly enhance the understanding of nonmethane alkane activation by noncanonical methyl-coenzyme M reductase enzymes and provide insights into additional metabolic steps and the mechanisms underlying syntrophic partnerships. Ultimately, this knowledge could lead to the biotechnological development of alkanogenic microorganisms to support the carbon neutrality of industrial processes.},
}
@article {pmid32316034,
year = {2020},
author = {Berkemer, SJ and McGlynn, SE},
title = {A new analysis of archaea-bacteria domain separation: variable phylogenetic distance and the tempo of early evolution.},
journal = {Molecular biology and evolution},
volume = {},
number = {},
pages = {},
doi = {10.1093/molbev/msaa089},
pmid = {32316034},
issn = {1537-1719},
abstract = {Comparative genomics and molecular phylogenetics are foundational for understanding biological evolution. Although many studies have been made with the aim of understanding the genomic contents of early life, uncertainty remains. A study by Weiss et al. (2016) identified a number of protein families in the last universal common ancestor of archaea and bacteria (LUCA) which were not found in previous works. Here we report new research that suggests the clustering approaches used in this previous study under-sampled protein families, resulting in incomplete phylogenetic trees which do not reflect protein family evolution. Phylogenetic analysis of protein families which include more sequence homologs rejects a simple LUCA hypothesis based on phylogenetic separation of the bacterial and archaeal domains for a majority of the previously identified LUCA proteins (∼82%). To supplement limitations of phylogenetic inference derived from incompletely populated orthologous groups, and to test the hypothesis of a period of rapid evolution preceding the separation of the domains, we compared phylogenetic distances both within, and between domains, for thousands of orthologous groups. We find a substantial diversity of interdomain vs. intradomain branch lengths, even among protein families which exhibit a single domain separating branch and are thought to be associated with the LUCA. Additionally, phylogenetic trees with long interdomain branches relative to intradomain branches are enriched in information categories of protein families in comparison to those associated with metabolic functions. These results provide a new view of protein family evolution, and temper claims about the phenotype and habitat of the LUCA.},
}
@article {pmid32302567,
year = {2020},
author = {López-García, P and Moreira, D},
title = {Cultured Asgard Archaea Shed Light on Eukaryogenesis.},
journal = {Cell},
volume = {181},
number = {2},
pages = {232-235},
doi = {10.1016/j.cell.2020.03.058},
pmid = {32302567},
issn = {1097-4172},
abstract = {The first cultured Asgard archaeon lives in metabolic symbiosis with hydrogen-scavenging microbes. Its full-genome analysis authenticates the existence of Asgard archaea, previously only known from metagenome-assembled genomes, confirms their closer phylogenetic relatedness to eukaryotes and reinforces the idea that the eukaryotic cell evolved from an integrated archaeal-bacterial syntrophic consortium.},
}
@article {pmid32302368,
year = {2020},
author = {Molnár, J and Magyar, B and Schneider, G and Laczi, K and Valappil, SK and Kovács, ÁL and Nagy, IK and Rákhely, G and Kovács, T},
title = {Identification of a novel archaea virus, detected in hydrocarbon polluted Hungarian and Canadian samples.},
journal = {PloS one},
volume = {15},
number = {4},
pages = {e0231864},
doi = {10.1371/journal.pone.0231864},
pmid = {32302368},
issn = {1932-6203},
abstract = {Metagenomics is a helpful tool for the analysis of unculturable organisms and viruses. Viruses that target bacteria and archaea play important roles in the microbial diversity of various ecosystems. Here we show that Methanosarcina virus MV (MetMV), the second Methanosarcina sp. virus with a completely determined genome, is characteristic of hydrocarbon pollution in environmental (soil and water) samples. It was highly abundant in Hungarian hydrocarbon polluted samples and its genome was also present in the NCBI SRA database containing reads from hydrocarbon polluted samples collected in Canada, indicating the stability of its niche and the marker feature of this virus. MetMV, as the only currently identified marker virus for pollution in environmental samples, could contribute to the understanding of the complicated network of prokaryotes and their viruses driving the decomposition of environmental pollutants.},
}
@article {pmid32300653,
year = {2020},
author = {Inoue, K and Tsunoda, SP and Singh, M and Tomida, S and Hososhima, S and Konno, M and Nakamura, R and Watanabe, H and Bulzu, PA and Banciu, HL and Andrei, AŞ and Uchihashi, T and Ghai, R and Béjà, O and Kandori, H},
title = {Schizorhodopsins: A family of rhodopsins from Asgard archaea that function as light-driven inward H+ pumps.},
journal = {Science advances},
volume = {6},
number = {15},
pages = {eaaz2441},
doi = {10.1126/sciadv.aaz2441},
pmid = {32300653},
issn = {2375-2548},
abstract = {Schizorhodopsins (SzRs), a rhodopsin family first identified in Asgard archaea, the archaeal group closest to eukaryotes, are present at a phylogenetically intermediate position between typical microbial rhodopsins and heliorhodopsins. However, the biological function and molecular properties of SzRs have not been reported. Here, SzRs from Asgardarchaeota and from a yet unknown microorganism are expressed in Escherichia coli and mammalian cells, and ion transport assays and patch clamp analyses are used to demonstrate SzR as a novel type of light-driven inward H+ pump. The mutation of a cytoplasmic glutamate inhibited inward H+ transport, suggesting that it functions as a cytoplasmic H+ acceptor. The function, trimeric structure, and H+ transport mechanism of SzR are similar to that of xenorhodopsin (XeR), a light-driven inward H+ pumping microbial rhodopsins, implying that they evolved convergently. The inward H+ pump function of SzR provides new insight into the photobiological life cycle of the Asgardarchaeota.},
}
@article {pmid32296409,
year = {2020},
author = {Tourte, M and Schaeffer, P and Grossi, V and Oger, PM},
title = {Functionalized Membrane Domains: An Ancestral Feature of Archaea?.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {526},
doi = {10.3389/fmicb.2020.00526},
pmid = {32296409},
issn = {1664-302X},
abstract = {Bacteria and Eukarya organize their plasma membrane spatially into domains of distinct functions. Due to the uniqueness of their lipids, membrane functionalization in Archaea remains a debated area. A novel membrane ultrastructure predicts that monolayer and bilayer domains would be laterally segregated in the hyperthermophilic archaeon Thermococcus barophilus. With very different physico-chemical parameters of the mono- and bilayer, each domain type would thus allow the docking of different membrane proteins and express different biological functions in the membrane. To estimate the ubiquity of this putative membrane ultrastructure in and out of the order Thermococcales, we re-analyzed the core lipid composition of all the Thermococcales type species and collected all the literature data available for isolated archaea. We show that all species of Thermococcales synthesize a mixture of diether bilayer forming and tetraether monolayer forming lipids, in various ratio from 10 to 80% diether in Pyrococcus horikoshii and Thermococcus gorgonarius, respectively. Since the domain formation prediction rests only on the coexistence of di- and tetraether lipids, we show that all Thermococcales have the ability for domain formation, i.e., differential functionalization of their membrane. Extrapolating this view to the whole Archaea domain, we show that almost all archaea also have the ability to synthesize di- and tetraether lipids, which supports the view that functionalized membrane domains may be shared between all Archaea. Hence domain formation and membrane compartmentalization may have predated the separation of the three domains of life and be essential for the cell cycle.},
}
@article {pmid32281023,
year = {2020},
author = {Fadhlaoui, K and Arnal, ME and Martineau, M and Camponova, P and Ollivier, B and O'Toole, PW and Brugère, JF},
title = {Archaea, specific genetic traits, and development of improved bacterial live biotherapeutic products: another face of next-generation probiotics.},
journal = {Applied microbiology and biotechnology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00253-020-10599-8},
pmid = {32281023},
issn = {1432-0614},
support = {16-IDEX-0001 CAP 20-25//ANR program ''Investissements d'Avenir'' CAP 20-25 &quot;Innovation-Research&quot; grant from Hub Innovergne/ ; },
abstract = {Trimethylamine (TMA) and its oxide TMAO are important biomolecules involved in disease-associated processes in humans (e.g., trimethylaminuria and cardiovascular diseases). TMAO in plasma (pTMAO) stems from intestinal TMA, which is formed from various components of the diet in a complex interplay between diet, gut microbiota, and the human host. Most approaches to prevent the occurrence of such deleterious molecules focus on actions to interfere with gut microbiota metabolism to limit the synthesis of TMA. Some human gut archaea however use TMA as terminal electron acceptor for producing methane, thus indicating that intestinal TMA does not accumulate in some human subjects. Therefore, a rational alternative approach is to eliminate neo-synthesized intestinal TMA. This can be achieved through bioremediation of TMA by these peculiar methanogenic archaea, either by stimulating or providing them, leading to a novel kind of next-generation probiotics referred to as archaebiotics. Finally, specific components which are involved in this archaeal metabolism could also be used as intestinal TMA sequesters, facilitating TMA excretion along with stool. Referring to a standard pharmacological approach, these TMA traps could be synthesized ex vivo and then delivered into the human gut. Another approach is the engineering of known probiotic strain in order to metabolize TMA, i.e., live engineered biotherapeutic products. These alternatives would require, however, to take into account the necessity of synthesizing the 22nd amino acid pyrrolysine, i.e., some specificities of the genetics of TMA-consuming archaea. Here, we present an overview of these different strategies and recent advances in the field that will sustain such biotechnological developments. KEY POINTS: • Some autochthonous human archaea can use TMA for their essential metabolism, a methyl-dependent hydrogenotrophic methanogenesis. • They could therefore be used as next-generation probiotics for preventing some human diseases, especially cardiovascular diseases and trimethylaminuria. • Their genetic capacities can also be used to design live recombinant biotherapeutic products. • Encoding of the 22nd amino acid pyrrolysine is necessary for such alternative developments.},
}
@article {pmid32267873,
year = {2020},
author = {Compte-Port, S and Fillol, M and Gich, F and Borrego, CM},
title = {Metabolic versatility of freshwater sedimentary archaea feeding on different organic carbon sources.},
journal = {PloS one},
volume = {15},
number = {4},
pages = {e0231238},
doi = {10.1371/journal.pone.0231238},
pmid = {32267873},
issn = {1932-6203},
abstract = {Members of the phylum Bathyarchaeota and the class Thermoplasmata are widespread in marine and freshwater sediments where they have been recognized as key players in the carbon cycle. Here, we tested the responsiveness of archaeal communities on settled plant debris and sediment from a karstic lake to different organic carbon amendments (amino acids, plant-derived carbohydrates, and aromatics) using a lab-scale microcosm. Changes in the composition and abundance of sediment and biofilm archaeal communities in both DNA and RNA fractions were assessed by 16S rRNA gene amplicon sequencing and qPCR, respectively, after 7 and 30 days of incubation. Archaeal communities showed compositional changes in terms of alpha and beta diversity in relation to the type of carbon source (amino acids vs. plant-derived compounds), the nucleic acid fraction (DNA vs. RNA), and the incubation time (7 vs. 30 days). Distinct groups within the Bathyarchaeota (Bathy-15 and Bathy-6) and the Thermoplasmata (MBG-D) differently reacted to carbon supplements as deduced from the analysis of RNA libraries. Whereas Bathyarchaeota in biofilms showed a long-term positive response to humic acids, their counterparts in the sediment were mainly stimulated by the addition of tryptophan, suggesting the presence of different subpopulations in both habitats. Overall, our work presents an in vitro assessment of the versatility of archaea inhabiting freshwater sediments towards organic carbon and introduces settled leaf litter as a new habitat for the Bathyarchaeota and the Thermoplasmata.},
}
@article {pmid32247910,
year = {2020},
author = {Jin, D and Zhang, F and Shi, Y and Kong, X and Xie, Y and Du, X and Li, Y and Zhang, R},
title = {Diversity of bacteria and archaea in the groundwater contaminated by chlorinated solvents undergoing natural attenuation.},
journal = {Environmental research},
volume = {185},
number = {},
pages = {109457},
doi = {10.1016/j.envres.2020.109457},
pmid = {32247910},
issn = {1096-0953},
abstract = {Chlorinated solvents (CS)-contaminated groundwater poses serious risks to the environment and public health. Microorganisms play a vital role in efficient remediation of CS. In this study, the microbial community (bacterial and archaeal) composition of three CS-contaminated groundwater wells located at an abandoned chemical factory which covers three orders of magnitude in concentration (0.02-16.15 mg/L) were investigated via 16S rRNA gene high-throughput sequencing. The results indicated that Proteobacteria and Thaumarchaeota were the most abundant bacterial and archaeal groups at the phylum level in groundwater, respectively. The major bacterial genera (Flavobacterium sp., Mycobacterium sp. and unclassified Parcubacteria taxa, etc.) and archaeal genera (Thaumarchaeota Group C3, Miscellaneous Crenarchaeotic Group and Miscellaneous Euryarchaeotic Group, etc.) might be involved in the dechlorination processes. In addition, Pearson's correlation analyses showed that alpha diversity of the bacterial community was not significantly correlated with CS concentration, while alpha diversity of archaeal community greatly decreased with the increased contamination of CS. Moreover, partial Mantel test indicated that oxidation-reduction potential, dissolved oxygen, temperature and methane concentration were major drivers of bacterial and archaeal community composition, whereas CS concentration had no significant impact, indicating that both indigenous bacterial and archaeal community compositions are capable of withstanding elevated CS contamination. This study improves our understanding of how the natural microbial community responds to high CS-contaminated groundwater.},
}
@article {pmid32232532,
year = {2020},
author = {Abril, AG and Rama, JLR and Sánchez-Pérez, A and Villa, TG},
title = {Prokaryotic sigma factors and their transcriptional counterparts in Archaea and Eukarya.},
journal = {Applied microbiology and biotechnology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00253-020-10577-0},
pmid = {32232532},
issn = {1432-0614},
abstract = {RNA polymerases (RNAPs) carry out transcription in the three domains of life, Bacteria, Archaea, and Eukarya. Transcription initiation is highly regulated by a variety of transcription factors, whose number and subunit complexity increase during evolution. This process is regulated in Bacteria by the σ factor, while the three eukaryotic RNAPs require a complex set of transcription factors (TFs) and a TATA-binding protein (TBP). The archaeal transcription system appears to be an ancestral version of the eukaryotic RNAPII, requiring transcription factor B (TFB), TBP, and transcription factor E (TFE). The function of the bacterial sigma (σ) factor has been correlated to the roles played by the eukaryotic RNAP II and the archaeal RNAP. In addition, σ factors, TFB, and TFIIB all contain multiple DNA binding helix-turn-helix (HTH) structural motifs; although TFIIB and TFB display two HTH domains, while the bacterial σ factor spans 4 HTH motifs. The sequence similarities and structure alignments of the bacterial σ factor, eukaryotic TFIIB, and archaeal TFB evidence that these three proteins are homologs.Key Points• Transcription initiation is highly regulated by TFs.• Transcription is finely regulated in all domains of life by different sets of TFs.• Specific TFs in Bacteria, Eukarya and Archaea are homologs.},
}
@article {pmid32214732,
year = {2010},
author = {Sun, J and Xu, Z and Hao, B},
title = {Whole-genome based Archaea phylogeny and taxonomy: A composition vector approach.},
journal = {Chinese science bulletin = Kexue tongbao},
volume = {55},
number = {22},
pages = {2323-2328},
doi = {10.1007/s11434-010-3008-8},
pmid = {32214732},
issn = {1001-6538},
abstract = {The newly proposed alignment-free and parameter-free composition vector (CVtree) method has been successfully applied to infer phylogenetic relationship of viruses, chloroplasts, bacteria, and fungi from their whole-genome data. In this study we pay special attention to the phylogenetic positions of 56 Archaea genomes among which 7 species have not been listed either in Bergey's Manual of Systematic Bacteriology or in Taxonomic Outline of Bacteria and Archaea (TOBA). By inspecting the stable monophyletic branchings in CVTrees reconstructed from a total of 861 genomes (56 Archaea plus 797 Bacteria, using 8 Eukarya as outgroups) definite taxonomic assignments were proposed for these not-fully-classified species. Further development of Archaea taxonomy may verify the predicted phylogenetic results of the CVTree approach.},
}
@article {pmid32201928,
year = {2020},
author = {Cai, M and Liu, Y and Yin, X and Zhou, Z and Friedrich, MW and Richter-Heitmann, T and Nimzyk, R and Kulkarni, A and Wang, X and Li, W and Pan, J and Yang, Y and Gu, JD and Li, M},
title = {Diverse Asgard archaea including the novel phylum Gerdarchaeota participate in organic matter degradation.},
journal = {Science China. Life sciences},
volume = {},
number = {},
pages = {},
doi = {10.1007/s11427-020-1679-1},
pmid = {32201928},
issn = {1869-1889},
abstract = {Asgard is an archaeal superphylum that might hold the key to understand the origin of eukaryotes, but its diversity and ecological roles remain poorly understood. Here, we reconstructed 15 metagenomic-assembled genomes from coastal sediments covering most known Asgard archaea and a novel group, which is proposed as a new Asgard phylum named as the &quot;Gerdarchaeota&quot;. Genomic analyses predict that Gerdarchaeota are facultative anaerobes in utilizing both organic and inorganic carbon. Unlike their closest relatives Heimdallarchaeota, Gerdarchaeota have genes encoding for cellulase and enzymes involved in the tetrahydromethanopterin-based Wood-Ljungdahl pathway. Transcriptomics showed that most of our identified Asgard archaea are capable of degrading organic matter, including peptides, amino acids and fatty acids, occupying ecological niches in different depths of layers of the sediments. Overall, this study broadens the diversity of the mysterious Asgard archaea and provides evidence for their ecological roles in coastal sediments.},
}
@article {pmid32156797,
year = {2020},
author = {Zhao, R and Dahle, H and Ramírez, GA and Jørgensen, SL},
title = {Indigenous Ammonia-Oxidizing Archaea in Oxic Subseafloor Oceanic Crust.},
journal = {mSystems},
volume = {5},
number = {2},
pages = {},
doi = {10.1128/mSystems.00758-19},
pmid = {32156797},
issn = {2379-5077},
abstract = {Oceanic ridge flank systems represent one of the largest and least-explored microbial habitats on Earth. Fundamental ecological questions regarding community activity, recruitment, and succession in this environment remain unanswered. Here, we investigated ammonia-oxidizing archaea (AOA) in the sediment-buried basalts on the oxic and young ridge flank at North Pond, a sediment-filled pond on the western flank of the Mid-Atlantic Ridge, and compared them with those in the overlying sediments and bottom seawater. Nitrification in the North Pond basement is thermodynamically favorable and is supported by a reaction-transport model simulating the dynamics of nitrate in the crustal fluids. Nitrification rate is estimated to account for 6% to 7% of oxygen consumption, which is similar to the ratios found in marine oxic sediments, suggesting that aerobic mineralization of organic matter is the major ammonium source for crustal nitrifiers. Using the archaeal 16S rRNA and amoA genes as phylogenetic markers, we show that AOA, composed solely of Nitrosopumilaceae, are the major archaeal dwellers at North Pond. Phylogenetic analysis reveals that the crustal AOA communities are distinct from those in the bottom seawater and the upper oxic sediments but are similar to those in the basal part of the overlying sediment column, suggesting either similar environmental selection or the dispersal of microbes across the sediment-basement interface. Additionally, quantitative abundance data suggest enrichment of the dominant Nitrosopumilaceae clade (Eta clade) in the basement compared to the seawater. This study explored AOA and their activity in the upper oceanic crust, and our results have ecological implications for the biogeochemical cycling of nitrogen in the crustal subsurface.IMPORTANCE Ridge flanks represent the major avenue of chemical and heat exchange between the Earth's oceans and the lithosphere and are thought to harbor an enormous and understudied biosphere. However, little is known about the diversity and functionality of the crustal biosphere. Here, we report an indigenous community of archaea specialized in ammonia oxidation (i.e., AOA) in the oxic oceanic crust at North Pond. These AOA are the dominant archaea and are likely responsible for most of the cycling taking place in the first step of nitrification, a feasible nitrogen cycling step in the oxic basement. The crustal AOA community structure significantly differs from that in deep ocean water but is similar to that of the community in the overlying sediments in close proximity. This report links the occurrence of AOA to their metabolic activity in the oxic subseafloor crust and suggests that ecological selection and in situ proliferation may shape the microbial community structure in the rocky subsurface.},
}
@article {pmid32148848,
year = {2020},
author = {Jeon, JH and Lee, HS and Shin, HC and Kwak, MJ and Kim, YG and Gruber, S and Oh, BH},
title = {Evidence for binary Smc complexes lacking kite subunits in archaea.},
journal = {IUCrJ},
volume = {7},
number = {Pt 2},
pages = {193-206},
doi = {10.1107/S2052252519016634},
pmid = {32148848},
issn = {2052-2525},
abstract = {SMC complexes play a central role in chromosome organization in all domains of life. The bacterial Smc-ScpAB complex is a three-subunit complex composed of Smc, ScpA and ScpB. ScpA bridges the two ATPase domains of the Smc homodimer, while ScpB, which belongs to the kite family of proteins, interacts with ScpA. The three subunits are known to be equally important for the function of Smc-ScpAB in bacteria. From crystallographic and biochemical studies, evidence is provided that six archaeal ScpA proteins are unable to interact with the only putative ScpB found in these species. Structure-based sequence alignment reveals that these archaeal ScpAs lack the ScpB-binding segment that is commonly present in the middle of bacterial ScpA sequences, which is thus responsible for their inability to interact with ScpB. ScpA proteins lacking the ScpB-binding segment are found to prevail in archaea. Moreover, two archaeal ScpA proteins with a longer middle region also failed to bind their putative ScpB partner. Furthermore, all or most species belonging to five out of 14 euryarchaeotal orders contain Smc and ScpA but not a detectable ScpB homologue. These data support the notion that archaeal Smc-based complexes generally function as a two-subunit complex composed of only Smc and ScpA.},
}
@article {pmid32126588,
year = {2020},
author = {Taylor, HB and Kurtz, HD},
title = {Composition, diversity, and activity of aerobic ammonia-oxidizing Bacteria and Archaea in the intertidal sands of a grand strand South Carolina beach.},
journal = {MicrobiologyOpen},
volume = {},
number = {},
pages = {e1011},
doi = {10.1002/mbo3.1011},
pmid = {32126588},
issn = {2045-8827},
abstract = {Aerobic ammonia oxidation to nitrite has been established as an important ecosystem process in regulating the level of nitrogen in marine ecosystems. This process is carried out by ammonia-oxidizing bacteria (AOB) within the classes Betaproteobacteria and Gammaproteobacteria and ammonia-oxidizing Archaea (AOA) from the phylum Thaumarchaeota, and the latter of which has been established as more prevalent in marine systems. This study investigated the presence, abundance, and activity of these groups of microbes at a beach near Springmaid Pier in Myrtle Beach, South Carolina, through the implementation of next generation sequencing, quantitative PCR (qPCR), and microcosm experiments to monitor activity. Sequencing analysis revealed a diverse community of ammonia-oxidizing microbes dominated by AOA classified within the family Nitrosopumilaceae, and qPCR revealed the abundance of AOA amoA genes over AOB by at least an order of magnitude in most samples. Microcosm studies indicate that the rates of potential ammonia oxidation in these communities satisfy Michaelis-Menten substrate kinetics and this process is more active at temperatures corresponding to summer months than winter. Potential rates in AOA medium were higher than that of AOB medium, indicating a potentially greater contribution of AOA to this process in this environment. In conclusion, this study provides further evidence of the dominance of AOA in these environments compared with AOB and highlights the overall efficiency of this process at turning over excess ammonium that may be present in these environments.},
}
@article {pmid32094586,
year = {2020},
author = {Sanders, TJ and Wenck, BR and Selan, JN and Barker, MP and Trimmer, SA and Walker, JE and Santangelo, TJ},
title = {FttA is a CPSF73 homologue that terminates transcription in Archaea.},
journal = {Nature microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41564-020-0667-3},
pmid = {32094586},
issn = {2058-5276},
support = {R01-GM100329-08//U.S. Department of Health &amp; Human Services | NIH | National Institute of General Medical Sciences (NIGMS)/ ; },
abstract = {Regulated gene expression is largely achieved by controlling the activities of essential, multisubunit RNA polymerase transcription elongation complexes (TECs). The extreme stability required of TECs to processively transcribe large genomic regions necessitates robust mechanisms to terminate transcription. Efficient transcription termination is particularly critical for gene-dense bacterial and archaeal genomes1-3 in which continued transcription would necessarily transcribe immediately adjacent genes and result in conflicts between the transcription and replication apparatuses4-6; the coupling of transcription and translation7,8 would permit the loading of ribosomes onto aberrant transcripts. Only select sequences or transcription termination factors can disrupt the otherwise extremely stable TEC and we demonstrate that one of the last universally conserved archaeal proteins with unknown biological function is the Factor that terminates transcription in Archaea (FttA). FttA resolves the dichotomy of a prokaryotic gene structure (operons and polarity) and eukaryotic molecular homology (general transcription apparatus) that is observed in Archaea. This missing link between prokaryotic and eukaryotic transcription regulation provides the most parsimonious link to the evolution of the processing activities involved in RNA 3'-end formation in Eukarya.},
}
@article {pmid32086308,
year = {2020},
author = {Wright, CL and Schatteman, A and Crombie, AT and Murrell, JC and Lehtovirta-Morley, LE},
title = {Inhibition of ammonia monooxygenase from ammonia oxidising archaea by linear and aromatic alkynes.},
journal = {Applied and environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1128/AEM.02388-19},
pmid = {32086308},
issn = {1098-5336},
abstract = {Ammonia monooxygenase (AMO) is a key nitrogen transforming enzyme belonging to the same copper-dependent membrane monooxygenase family (CuMMO) as the particulate methane monooxygenase (pMMO). The AMO from ammonia oxidising archaea (AOA) is very divergent from both the AMO of ammonia oxidising bacteria (AOB) and the pMMO from methanotrophs and little is known about the structure or substrate range of the archaeal AMO. This study compares inhibition by C2-C8 linear 1-alkynes of AMO from two phylogenetically distinct strains of AOA, &quot;Candidatus Nitrosocosmicus franklandus&quot; C13 and &quot;Candidatus Nitrosotalea sinensis&quot; Nd2, with AMO from Nitrosomonas europaea and pMMO from Methylococcus capsulatus (Bath). An increased sensitivity of the archaeal AMO to short-chain-length alkynes (≤C5) appeared to be conserved across AOA lineages. Similarities in C2-C8 alkyne inhibition profiles between AMO from AOA and pMMO from M. capsulatus suggested that the archaeal AMO has a narrower substrate range compared to that of N. europaea AMO. Inhibition of AMO from &quot;Ca. Nitrosocosmicus franklandus&quot; and N. europaea by the aromatic alkyne phenylacetylene was also investigated. Kinetic data revealed that the mechanism by which phenylacetylene inhibits &quot;Ca. Nitrosocosmicus franklandus&quot; and N. europaea is different, indicating differences in the AMO active site between AOA and AOB. Phenylacetylene was found to be a specific and irreversible inhibitor of AMO from &quot;Ca. Nitrosocosmicus franklandus&quot; which does not compete with NH3 for binding at the active site.ImportanceArchaeal and bacterial ammonia oxidisers (AOA and AOB) initiate nitrification by oxidising ammonia to hydroxylamine, a reaction catalysed by ammonia monooxygenase (AMO). AMO enzyme is difficult to purify in active form and its structure and biochemistry remain largely unexplored. The bacterial AMO and the closely related particulate methane monooxygenase (pMMO) have a broad range of hydrocarbon co-oxidation substrates. This study provides insights into the AMO of previously unstudied archaeal genera, by comparing the response of the archaeal AMO, a bacterial AMO and pMMO to inhibition by linear 1-alkynes and the aromatic alkyne, phenylacetylene. Reduced sensitivity to inhibition by larger alkynes suggests that the archaeal AMO has a narrower hydrocarbon substrate range compared to the bacterial AMO, as previously reported for other genera of AOA. Phenylacetylene inhibited the archaeal and bacterial AMO at different thresholds and by different mechanisms of inhibition, highlighting structural differences between the two forms of monooxygenase.},
}
@article {pmid32084690,
year = {2020},
author = {Yang, X and Ni, K and Shi, Y and Yi, X and Ji, L and Ma, L and Ruan, J},
title = {Heavy nitrogen application increases soil nitrification through ammonia-oxidizing bacteria rather than archaea in acidic tea (Camellia sinensis L.) plantation soil.},
journal = {The Science of the total environment},
volume = {717},
number = {},
pages = {137248},
doi = {10.1016/j.scitotenv.2020.137248},
pmid = {32084690},
issn = {1879-1026},
abstract = {Nitrogen (N) fertilizer is widely used in agricultural ecosystems and influences N transformation processes in the soil such as nitrification. However, whether nitrification is primarily dominated by ammonia-oxidizing bacteria (AOB) or archaea (AOA) under heavy N application is still under debate. In the present work, the effect of long-term (12 years) N fertilization on soil nitrification and the key influencing factors were investigated in acidic tea plantation soil that received four different rates of N application (0, 119, 285, and 569 kg N ha-1 yr-1). Nitrification potential was measured and partitioned using chemical inhibitors. The abundance of functional genes involved in ammonia oxidation was quantified using quantitative polymerase chain reaction (qPCR). Ammonia-oxidizing communities were identified by shotgun metagenome sequencing. Potential nitrification rate in tea plantation soil was mainly dominated by autotrophic nitrification (PNRA) (71-79%). PNRA and heterotrophic nitrification (PNRH) were both significantly increased by heavy N (569 kg ha-1) application. Moreover, PNRA was mainly due to the contribution of AOB (52-66%) in N-treated soils, and N569 significantly increased the AOB contribution without affecting the AOA contribution. N569 increased the functional gene abundance of AOB and TAO100 (a non-halophilic γ-AOB) but decreased that of AOA. The dominant AOB (Nitrosomonas, Nitrosospira, and Nitrosococcus), AOA (Nitrososphaera and Nitrosopumilus) and commamox (Nitrospira) groups were profoundly altered by long-term N application rates. Partial least squares regression showed that total nitrification (PNRT), PNRA, and PNRAOB were primarily explained by the functional gene abundance of nitrifiers whereas PNRH and PNRAOA were closely associated with soil and pruned litter properties. Moreover, structural equation modeling (SEM) revealed that long-term N application significantly and indirectly affected nitrification potential by directly influencing soil properties, pruned litter properties, and functional gene abundance. Understanding the relative contribution of AOA and AOB to nitrification may help to better regulate N fertilizer use in agricultural ecosystems.},
}
@article {pmid32073658,
year = {2020},
author = {Eckl, DB and Huber, H and Bäumler, W},
title = {First Report on Photodynamic Inactivation of Archaea Including a Novel Method for High-Throughput Reduction Measurement.},
journal = {Photochemistry and photobiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/php.13229},
pmid = {32073658},
issn = {1751-1097},
abstract = {Archaea are considered third, independent domain of living organisms besides eukaryotic and bacterial cells. To date, no report is available of photodynamic inactivation (PDI) of any Archaea cells. Two commercially available photosensitizers (SAPYR, TMPyP) were used to investigate photodynamic inactivation of Halobacterium salinarum. In addition, a novel high throughput method was tested to evaluate microbial reduction in vitro. Due to the high salt content of the culture medium, the physical and chemical properties of photosensitizers were analyzed via spectroscopy and fluorescence based DPBF assays. Attachment or uptake of photosensitizers to or in archaeal cells was investigated. The photodynamic inactivation of Halobacterium salinarum was evaluated via growth curve method allowing a high throughput of samples. The presented results indicate that the photodynamic mechanisms are working even in high salt environments. Either photosensitizer inactivated the bacterial cells with a reduction of 99.9% at least. The growth curves provided a fast and precise measurement of cell viability. The results show for the first time that PDI can kill not only bacterial cells but also robust Archaea. The novel method for generating high throughput growth curves provides benefits for future research regarding antimicrobial substances in general.},
}
@article {pmid32071162,
year = {2020},
author = {Liechty, Z and Santos-Medellín, C and Edwards, J and Nguyen, B and Mikhail, D and Eason, S and Phillips, G and Sundaresan, V},
title = {Comparative Analysis of Root Microbiomes of Rice Cultivars with High and Low Methane Emissions Reveals Differences in Abundance of Methanogenic Archaea and Putative Upstream Fermenters.},
journal = {mSystems},
volume = {5},
number = {1},
pages = {},
doi = {10.1128/mSystems.00897-19},
pmid = {32071162},
issn = {2379-5077},
abstract = {Rice cultivation worldwide accounts for ∼7 to 17% of global methane emissions. Methane cycling in rice paddies is a microbial process not only involving methane producers (methanogens) and methane metabolizers (methanotrophs) but also other microbial taxa that affect upstream processes related to methane metabolism. Rice cultivars vary in their rates of methane emissions, but the influence of rice genotypes on methane cycling microbiota has been poorly characterized. Here, we profiled the rhizosphere, rhizoplane, and endosphere microbiomes of a high-methane-emitting cultivar (Sabine) and a low-methane-emitting cultivar (CLXL745) throughout the growing season to identify variations in the archaeal and bacterial communities relating to methane emissions. The rhizosphere of the high-emitting cultivar was enriched in methanogens compared to that in the low emitter, whereas the relative abundances of methanotrophs between the cultivars were not significantly different. Further analysis of cultivar-sensitive taxa identified families enriched in the high emitter that are associated with methanogenesis-related processes. The high emitter had greater relative abundances of sulfate-reducing and iron-reducing taxa which peak earlier in the season than methanogens and are necessary to lower soil oxidation reduction potential before methanogenesis can occur. The high emitter also had a greater abundance of fermentative taxa which produce methanogenesis precursors (acetate, CO2, and H2). Furthermore, the high emitter was enriched in taxa related to acetogenesis which compete with methanogens for CO2 and H2 These taxa were enriched in a spatio-specific manner and reveal a complex network of microbial interactions on which plant genotype-dependent factors can act to affect methanogenesis and methane emissions.IMPORTANCE Rice cultivation is a major source of anthropogenic emissions of methane, a greenhouse gas with a potentially severe impact on climate change. Emission variation between rice cultivars suggests the feasibility of breeding low-emission rice, but there is a limited understanding of how genotypes affect the microbiota involved in methane cycling. Here, we show that the root microbiome of the high-emitting cultivar is enriched both in methanogens and in taxa associated with fermentation, iron, and sulfate reduction and acetogenesis, processes that support methanogenesis. Understanding how cultivars affect microbes with methanogenesis-related functions is vital for understanding the genetic basis for methane emission in rice and can aid in the development of breeding programs that reduce the environmental impact of rice cultivation.},
}
@article {pmid32068866,
year = {2020},
author = {Badel, C and Da Cunha, V and Forterre, P and Oberto, J},
title = {Pervasive suicidal integrases in deep-sea archaea.},
journal = {Molecular biology and evolution},
volume = {},
number = {},
pages = {},
doi = {10.1093/molbev/msaa041},
pmid = {32068866},
issn = {1537-1719},
abstract = {Mobile genetic elements often encode integrases which catalyze the site-specific insertion of their genetic information into the host genome and the reverse reaction of excision. Hyperthermophilic archaea harbor integrases belonging to the SSV-family which carry the MGE recombination site within their open reading frame. Upon integration into the host genome, SSV integrases disrupt their own gene into two inactive pseudogenes and are termed suicidal for this reason. The evolutionary maintenance of suicidal integrases, concurring with the high prevalence and multiples recruitments of these recombinases by archaeal MGEs, is highly paradoxical. To elucidate this phenomenon, we analyzed the wide phylogenomic distribution of a prominent class of suicidal integrases which revealed a highly variable integration site specificity. Our results highlighted the remarkable hybrid nature of these enzymes encoded from the assembly of inactive pseudogenes of different origins. The characterization of the biological properties of one of these integrases, IntpT26-2 showed that this enzyme was active over a wide range of temperatures up to 99 °C and displayed a less stringent site specificity requirement than comparable integrases. These observations concurred in explaining the pervasiveness of these suicidal integrases in the most hyperthermophilic organisms. The biochemical and phylogenomic data presented here revealed a target site switching system operating on highly thermostable integrases and suggested a new model for split gene reconstitution. By generating fast-evolving pseudogenes at high frequency, suicidal integrases constitute a powerful model to approach the molecular mechanisms involved in the generation of active genes variants by the recombination of proto-genes.},
}
@article {pmid32055827,
year = {2020},
author = {Tästensen, JB and Johnsen, U and Reinhardt, A and Schönheit, P},
title = {D-Galactose catabolism in archaea: Operation of the DeLey-Doudoroff pathway in Haloferax volcanii.},
journal = {FEMS microbiology letters},
volume = {},
number = {},
pages = {},
doi = {10.1093/femsle/fnaa029},
pmid = {32055827},
issn = {1574-6968},
abstract = {The haloarchaeon Haloferax volcanii was found to grow on D-galactose as carbon and energy source. Here we report a comprehensive analysis of D-galactose catabolism in H. volcanii. Genome analyses indicated a cluster of genes encoding putative enzymes of the DeLey-Doudoroff pathway for D-galactose degradation including galactose dehydrogenase, galactonate dehydratase, 2-keto-3-deoxygalactonate kinase and 2-keto-3-deoxy-6-phosphogalactonate (KDPGal) aldolase. The recombinant galactose dehydrogenase and galactonate dehydratase showed high specificity for D-galactose and galactonate, respectively, whereas KDPGal aldolase was promiscuous in utilizing KDPGal and also the C4 epimer 2-keto-3-deoxy-6-phosphogluconate as substrates. Growth studies with knock-out mutants indicated the functional involvement of galactose dehydrogenase, galactonate dehydratase and KDPGal aldolase in D-galactose degradation. Further, the transcriptional regulator GacR was identified which was characterized as an activator of genes of the DeLey-Doudoroff pathway. Finally, genes were identified encoding components of an ABC transporter and a knock-out mutant of the substrate binding protein indicated the functional involvement of this transporter in D-galactose uptake. This is the first report of D-galactose degradation via the DeLey-Doudoroff pathway in the domain of archaea.},
}
@article {pmid32047285,
year = {2020},
author = {Roux, S and Krupovic, M and Daly, RA and Borges, AL and Nayfach, S and Schulz, F and Sharrar, A and Matheus Carnevali, PB and Cheng, JF and Ivanova, NN and Bondy-Denomy, J and Wrighton, KC and Woyke, T and Visel, A and Kyrpides, NC and Eloe-Fadrosh, EA},
title = {Author Correction: Cryptic inoviruses revealed as pervasive in bacteria and archaea across Earth's biomes.},
journal = {Nature microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41564-020-0681-5},
pmid = {32047285},
issn = {2058-5276},
abstract = {An amendment to this paper has been published and can be accessed via a link at the top of the paper.},
}
@article {pmid32041059,
year = {2020},
author = {Roy, D and McEvoy, J and Khan, E},
title = {Abundance and activity of ammonia oxidizing archaea and bacteria in bulk water and biofilm in water supply systems practicing chlorination and chloramination: Full and laboratory scale investigations.},
journal = {The Science of the total environment},
volume = {715},
number = {},
pages = {137043},
doi = {10.1016/j.scitotenv.2020.137043},
pmid = {32041059},
issn = {1879-1026},
abstract = {The abundance and nitrification activity of ammonia oxidizing archaea (AOA) and ammonia oxidizing bacteria (AOB) in bulk water and biofilm in chloraminated and chlorinated water supply systems were investigated. The abundance of AOB varied between cold and warm periods while that was the case for AOA only in biofilm. Lower ammonia concentrations favored the abundance of AOA over AOB. AOA and AOB were found more in distal zones of the distribution system (DS). Higher numbers of AOA and AOB were observed in DS associated with chloramination compared to those associated with chlorination. Significant positive correlations between ammonia-N in bulk water and AOA indicate a possibility of involvement of AOA in nitrification in DS. A separate laboratory-based experiment simulating DS condition was conducted to understand the effects of chlorine and chloramine dosages and temperature on AOA and AOB. AOA were inhibited less than AOB in the presence of lower concentrations of chlorine and chloramine (1.5 and 2.0 mg/L chlorine; 0.05-0.1 and 0.3-0.4 mg/L chloramine) while both of them were not detected at higher dosages (2.5 mg/L chlorine and 1.5-1.6 mg/L chloramine). At a low temperature (10-12 °C), chloramine and chlorine provided similar inhibition trends in which AOB were inhibited more than AOA. At a high temperature (25 °C), chloramine was less inhibitory to AOA and AOB than chlorine.},
}
@article {pmid32030412,
year = {2020},
author = {Phung, DK and Etienne, C and Batista, M and Langendijk-Genevaux, P and Moalic, Y and Laurent, S and Liuu, S and Morales, V and Jebbar, M and Fichant, G and Bouvier, M and Flament, D and Clouet-d'Orval, B},
title = {RNA processing machineries in Archaea: the 5'-3' exoribonuclease aRNase J of the β-CASP family is engaged specifically with the helicase ASH-Ski2 and the 3'-5' exoribonucleolytic RNA exosome machinery.},
journal = {Nucleic acids research},
volume = {},
number = {},
pages = {},
doi = {10.1093/nar/gkaa052},
pmid = {32030412},
issn = {1362-4962},
abstract = {A network of RNA helicases, endoribonucleases and exoribonucleases regulates the quantity and quality of cellular RNAs. To date, mechanistic studies focussed on bacterial and eukaryal systems due to the challenge of identifying the main drivers of RNA decay and processing in Archaea. Here, our data support that aRNase J, a 5'-3' exoribonuclease of the β-CASP family conserved in Euryarchaeota, engages specifically with a Ski2-like helicase and the RNA exosome to potentially exert control over RNA surveillance, at the vicinity of the ribosome. Proteomic landscapes and direct protein-protein interaction analyses, strengthened by comprehensive phylogenomic studies demonstrated that aRNase J interplay with ASH-Ski2 and a cap exosome subunit. Finally, Thermococcus barophilus whole-cell extract fractionation experiments provide evidences that an aRNase J/ASH-Ski2 complex might exist in vivo and hint at an association of aRNase J with the ribosome that is emphasised in absence of ASH-Ski2. Whilst aRNase J homologues are found among bacteria, the RNA exosome and the Ski2-like RNA helicase have eukaryotic homologues, underlining the mosaic aspect of archaeal RNA machines. Altogether, these results suggest a fundamental role of β-CASP RNase/helicase complex in archaeal RNA metabolism.},
}
@article {pmid32025518,
year = {2020},
author = {Lyubetsky, VA and Zverkov, OA and Rubanov, LI and Seliverstov, AV},
title = {Optimal Growth Temperature and Intergenic Distances in Bacteria, Archaea, and Plastids of Rhodophytic Branch.},
journal = {BioMed research international},
volume = {2020},
number = {},
pages = {3465380},
doi = {10.1155/2020/3465380},
pmid = {32025518},
issn = {2314-6141},
abstract = {The lengths of intergenic regions between neighboring genes that are convergent, divergent, or unidirectional were calculated for plastids of the rhodophytic branch and complete archaeal and bacterial genomes. Statistically significant linear relationships between any pair of the medians of these three length types have been revealed in each genomic group. Exponential relationships between the optimal growth temperature and each of the three medians have been revealed as well. The leading coefficients of the regression equations relating all pairs of the medians as well as temperature and any of the medians have the same sign and order of magnitude. The results obtained for plastids, archaea, and bacteria are also similar at the qualitative level. For instance, the medians are always low at high temperatures. At low temperatures, the medians tend to statistically significant greater values and scattering. The original model was used to test our hypothesis that the intergenic distances are optimized in particular to decrease the competition of RNA polymerases within the locus that results in transcribing shortened RNAs. Overall, this points to an effect of temperature for both remote and close genomes.},
}
@article {pmid32014611,
year = {2020},
author = {Fusco, S and Aulitto, M and Iacobucci, I and Crocamo, G and Pucci, P and Bartolucci, S and Monti, M and Contursi, P},
title = {The interaction between the F55 virus-encoded transcription regulator and the RadA host recombinase reveals a common strategy in Archaea and Bacteria to sense the UV-induced damage to the host DNA.},
journal = {Biochimica et biophysica acta. Gene regulatory mechanisms},
volume = {},
number = {},
pages = {194493},
doi = {10.1016/j.bbagrm.2020.194493},
pmid = {32014611},
issn = {1876-4320},
abstract = {Sulfolobus spindle-shaped virus 1 is the only UV-inducible member of the virus family Fuselloviridae. Originally isolated from Saccharolobus shibatae B12, it can also infect Saccharolobus solfataricus. Like the CI repressor of the bacteriophage λ, the SSV1-encoded F55 transcription repressor acts as a key regulator for the maintenance of the SSV1 carrier state. In particular, F55 binds to tandem repeat sequences located within the promoters of the early and UV-inducible transcripts. Upon exposure to UV light, a temporally coordinated pattern of gene expression is triggered. In the case of the better characterized bacteriophage λ, the switch from lysogenic to lytic development is regulated by a crosstalk between the virus encoded CI repressor and the host RecA, which regulates also the SOS response. For SSV1, instead, the regulatory mechanisms governing the switch from the carrier to the induced state have not been completely unravelled. In this study we have applied an integrated biochemical approach based on a variant of the EMSA assay coupled to mass spectrometry analyses to identify the proteins associated with F55 when bound to its specific DNA promoter sequences. Among the putative F55 interactors, we identified RadA and showed that the archaeal molecular components F55 and RadA are functional homologs of bacteriophage λ (factor CI) and Escherichia coli (RecA) system.},
}
@article {pmid32013868,
year = {2020},
author = {Zhang, RY and Zou, B and Yan, YW and Jeon, CO and Li, M and Cai, M and Quan, ZX},
title = {Design of targeted primers based on 16S rRNA sequences in meta-transcriptomic datasets and identification of a novel taxonomic group in the Asgard archaea.},
journal = {BMC microbiology},
volume = {20},
number = {1},
pages = {25},
doi = {10.1186/s12866-020-1707-0},
pmid = {32013868},
issn = {1471-2180},
support = {2018YFC0310600//the National Key R&amp;D Program of China/ ; 31870109//National Natural Science Foundation of China/ ; 31170114//National Natural Science Foundation of China/ ; },
abstract = {BACKGROUND: Amplification of small subunit (SSU) rRNA genes with universal primers is a common method used to assess microbial populations in various environmental samples. However, owing to limitations in coverage of these universal primers, some microorganisms remain unidentified. The present study aimed to establish a method for amplifying nearly full-length SSU rRNA gene sequences of previously unidentified prokaryotes, using newly designed targeted primers via primer evaluation in meta-transcriptomic datasets.<br><br>METHODS: Primer binding regions of universal primer 8F/Arch21F for bacteria or archaea were used for primer evaluation of SSU rRNA sequences in meta-transcriptomic datasets. Furthermore, targeted forward primers were designed based on SSU rRNA reads from unclassified groups unmatched with the universal primer 8F/Arch21F, and these primers were used to amplify nearly full-length special SSU rRNA gene sequences along with universal reverse primer 1492R. Similarity and phylogenetic analysis were used to confirm their novel status.<br><br>RESULTS: Using this method, we identified unclassified SSU rRNA sequences that were not matched with universal primer 8F and Arch21F. A new group within the Asgard superphylum was amplified by the newly designed specific primer based on these unclassified SSU rRNA sequences by using mudflat samples.<br><br>CONCLUSION: We showed that using specific primers designed based on universal primer evaluation from meta-transcriptomic datasets, identification of novel taxonomic groups from a specific environment is possible.},
}
@article {pmid32006018,
year = {2020},
author = {Menéndez-Serra, M and Ontiveros, V and Triadó-Margarit, X and Alonso, D and Casamayor, E},
title = {Dynamics and ecological distributions of the Archaea microbiome from inland saline lakes (Monegros Desert, Spain).},
journal = {FEMS microbiology ecology},
volume = {},
number = {},
pages = {},
doi = {10.1093/femsec/fiaa019},
pmid = {32006018},
issn = {1574-6941},
abstract = {We characterized the rich Archaea microbiome of shallow inland lakes (Monegros Desert, NE Spain) by 16S rRNA gene tag sequencing covering a wide salinity range (0.1-40% w/v) along three years. Up to 990 OTUs (<97% identity) were detected allocated in 14 major archaeal phyla and heterogeneously distributed along the salt gradient. Dynamics and idiosyncratic ecological distributions were uncovered for the different phyla. A high genetic richness was observed for Woesearchaota and Pacearchaeota (>370 OTUs each), followed by Halobacteria (105), Nanohaloarchaeota (62) and Thermoplasmata (19). Overall, the distribution of genetic richness was strongly correlated with environmental niche amplitude, but not with occurrence. We unveiled high occurrence for a very rich Woesearchaeota assemblage, and an unexpected positive correlation of Pacearchaeota abundance with salinity at >15% dissolved salt content. The estimated dynamic behaviour (temporal 'turnover' rates of presence/absence data) unveiled Thaumarchaeota and Halobacteria as the most dynamic groups, and Aenigmarchaeota and Thermoplasmata as the most stable. The DPANN Pacearchaeota, Woesearchaeota, and Nanohaloarchaeota showed intermediate rates, suggesting higher resilience to environmental perturbations. A rich and dynamic Archaea microbiome was unveiled including unseen ecological traits for relevant members of the still largely unknown DPANN group, supporting a strong ecological differentiation between Pacearchaeota and Woesearchaeota.},
}
@article {pmid31999377,
year = {2020},
author = {Roy, C and Kumar, R and Datta, S},
title = {Comparative Studies on Ion-pair Energetic, Distribution among Three Domains of Life: Archaea, Eubacteria and Eukarya.},
journal = {Proteins},
volume = {},
number = {},
pages = {},
doi = {10.1002/prot.25878},
pmid = {31999377},
issn = {1097-0134},
abstract = {Salt-bridges play a unique role in the structural and functional stability of proteins, especially under harsh environments. How these salt-bridges contribute to the overall thermodynamic stability of protein structure and function across different domains of life is elusive still date. To address the issue, statistical analyses on the energies of salt-bridges, involved in proteins' structure and function, are performed across three domains of life i.e. archaea, eubacteria and eukarya. Results show that although the majority of salt-bridges are stable and conserved, yet the stability of archaeal proteins (∆∆Gnet = -5.06±3.8) is much more than that of eubacteria ∆∆Gnet = -3.7±2.9) and eukarya ∆∆Gnet = -3.54±3.1). Unlike earlier study with archaea, in eukarya and eubacteria, not all buried salt-bridge in our dataset are stable. Buried salt-bridges play surprising role in protein stability, whose variations are clearly observed among these domains. Greater desolvation penalty of buried salt-bridges is compensated by stable network of salt-bridges apart from equal contribution of bridge and background energy terms. On the basis proteins' secondary structure, topology and evolution, our observation show that salt-bridges when present closer to each other in sequence tend to form a greater number. Overall, our comparative study provides insight into the role of specific electrostatic interactions in proteins from different domains of life, which we hope, would be useful for protein engineering and bioinformatics study. This article is protected by copyright. All rights reserved.},
}
@article {pmid31994760,
year = {2020},
author = {Eichler, J},
title = {Modifying Post-Translational Modifications: A Strategy Used by Archaea for Adapting to Changing Environments?: Manipulating the Extent, Position, or Content of Post-Translational Modifications May Help Archaea Adapt to Environmental Change.},
journal = {BioEssays : news and reviews in molecular, cellular and developmental biology},
volume = {},
number = {},
pages = {e1900207},
doi = {10.1002/bies.201900207},
pmid = {31994760},
issn = {1521-1878},
support = {2193/16//ISF-NSFC joint research program/ ; },
abstract = {In concert with the selective pressures affecting protein folding and function in the extreme environments in which they can exist, proteins in Archaea have evolved to present permanent molecular adaptations at the amino acid sequence level. Such adaptations may not, however, suffice when Archaea encounter transient changes in their surroundings. Post-translational modifications offer a rapid and reversible layer of adaptation for proteins to cope with such situations. Here, it is proposed that Archaea further augment their ability to survive changing growth conditions by modifying the extent, position, and, where relevant, the composition of different post-translational modifications, as a function of the environment. Support for this hypothesis comes from recent reports describing how patterns of protein glycosylation, methylation, and other post-translational modifications of archaeal proteins are altered in response to environmental change. Indeed, adjusting post-translational modifications as a means to cope with environmental variability may also hold true beyond the Archaea.},
}
@article {pmid31949227,
year = {2020},
author = {Guo, H and Ma, L and Liang, Y and Hou, Z and Min, W},
title = {Response of ammonia-oxidizing Bacteria and Archaea to long-term saline water irrigation in alluvial grey desert soils.},
journal = {Scientific reports},
volume = {10},
number = {1},
pages = {489},
doi = {10.1038/s41598-019-57402-x},
pmid = {31949227},
issn = {2045-2322},
support = {41661055//The National Natural Science Foundation of China/ ; },
abstract = {Soil nitrification via ammonia oxidation is a key ecosystem process in terrestrial environments, but little is known of how increasing irrigation of farmland soils with saline waters effects these processes. We investigated the effects of long-term irrigation with saline water on the abundances and community structures of ammonia-oxidizing bacteria (AOB) and archaea (AOA). Irrigation with brackish or saline water increased soil salinity (EC1:5) and NH4-N compared to irrigation with freshwater, while NO3-N, potential nitrification rates (PNR) and amoA gene copy numbers of AOA and AOB decreased markedly under irrigation regimes with saline waters. Moreover, irrigation with brackish water lowered AOA/AOB ratios. PNR was positively correlated with AOA and AOB amoA gene copy numbers across treatments. Saline and brackish water irrigation significantly increased the diversity of AOA, as noted by Shannon index values, while saline water irrigation markedly reduced AOB diversity. In addition, irrigation with brackish or fresh waters resulted in higher proportions of unclassified taxa in the AOB communities. However, irrigation with saline water led to higher proportions of unclassified taxa in the AOA communities along with the Candidatus Nitrosocaldus genus, as compared to soils irrigated with freshwater. AOA community structures were closely associated with soil salinity, NO3-N, and pH, while AOB communities were only significantly associated with NO3-N and pH. These results suggest that salinity was the dominant factor affecting the growth of ammonia-oxidizing microorganisms and community structure. These results can provide a scientific basis for further exploring the response mechanism of ammonia-oxidizing microorganisms and their roles in nitrogen transformation in alluvial grey desert soils of arid areas.},
}
@article {pmid31942065,
year = {2020},
author = {},
title = {The life of archaea.},
journal = {Nature},
volume = {577},
number = {7790},
pages = {294},
doi = {10.1038/d41586-020-00087-4},
pmid = {31942065},
issn = {1476-4687},
}
@article {pmid31941956,
year = {2020},
author = {Besseling, MA and Hopmans, EC and Bale, NJ and Schouten, S and Damsté, JSS and Villanueva, L},
title = {The absence of intact polar lipid-derived GDGTs in marine waters dominated by Marine Group II: Implications for lipid biosynthesis in Archaea.},
journal = {Scientific reports},
volume = {10},
number = {1},
pages = {294},
doi = {10.1038/s41598-019-57035-0},
pmid = {31941956},
issn = {2045-2322},
abstract = {The marine pelagic archaeal community is dominated by three major groups, the marine group I (MGI) Thaumarchaeota, and the marine groups II and III (MGII and MGIII) Euryarchaeota. Studies of both MGI cultures and the environment have shown that the MGI core membrane lipids are predominantly composed of glycerol dibiphytanyl glycerol tetraether (GDGT) lipids and the diether lipid archaeol. However, there are no cultured representatives of MGII and III archaea and, therefore, both their membrane lipid composition and potential contribution to the marine archaeal lipid pool remain unknown. Here, we show that GDGTs present in suspended particulate matter of the (sub)surface waters of the North Atlantic Ocean and the coastal North Sea are derived from MGI archaea, and that MGII archaea do not significantly contribute to the pool of GDGTs and archaeol. This implies, in contrast to previous suggestions, that their lipids do not affect the widely used sea surface temperature proxy TEX86. These findings also indicate that MGII archaea are not able to produce any known archaeal lipids, implying that our understanding of the evolution of membrane lipid biosynthesis in Archaea is far from complete.},
}
@article {pmid31937639,
year = {2020},
author = {Barco, RA and Garrity, GM and Scott, JJ and Amend, JP and Nealson, KH and Emerson, D},
title = {A Genus Definition for Bacteria and Archaea Based on a Standard Genome Relatedness Index.},
journal = {mBio},
volume = {11},
number = {1},
pages = {},
doi = {10.1128/mBio.02475-19},
pmid = {31937639},
issn = {2150-7511},
abstract = {Genus assignment is fundamental in the characterization of microbes, yet there is currently no unambiguous way to demarcate genera solely using standard genomic relatedness indices. Here, we propose an approach to demarcate genera that relies on the combined use of the average nucleotide identity, genome alignment fraction, and the distinction between type- and non-type species. More than 3,500 genomes representing type strains of species from >850 genera of either bacterial or archaeal lineages were tested. Over 140 genera were analyzed in detail within the taxonomic context of order/family. Significant genomic differences between members of a genus and type species of other genera in the same order/family were conserved in 94% of the cases. Nearly 90% (92% if polyphyletic genera are excluded) of the type strains were classified in agreement with current taxonomy. The 448 type strains that need reclassification directly impact 33% of the genera analyzed in detail. The results provide a first line of evidence that the combination of genomic indices provides added resolution to effectively demarcate genera within the taxonomic framework that is currently based on the 16S rRNA gene. We also identify the emergence of natural breakpoints at the genome level that can further help in the circumscription of taxa, increasing the proportion of directly impacted genera to at least 43% and pointing at inaccuracies on the use of the 16S rRNA gene as a taxonomic marker, despite its precision. Altogether, these results suggest that genomic coherence is an emergent property of genera in Bacteria and ArchaeaIMPORTANCE In recent decades, the taxonomy of Bacteria and Archaea, and therefore genus designation, has been largely based on the use of a single ribosomal gene, the 16S rRNA gene, as a taxonomic marker. We propose an approach to delineate genera that excludes the direct use of the 16S rRNA gene and focuses on a standard genome relatedness index, the average nucleotide identity. Our findings are of importance to the microbiology community because the emergent properties of Bacteria and Archaea that are identified in this study will help assign genera with higher taxonomic resolution.},
}
@article {pmid31926374,
year = {2020},
author = {Wang, C and Tang, S and He, X and Ji, G},
title = {The abundance and community structure of active ammonia-oxidizing archaea and ammonia-oxidizing bacteria shape their activities and contributions in coastal wetlands.},
journal = {Water research},
volume = {171},
number = {},
pages = {115464},
doi = {10.1016/j.watres.2019.115464},
pmid = {31926374},
issn = {1879-2448},
abstract = {Aerobic ammonia oxidation, an important part of the global nitrogen cycle, is thought to be jointly driven by ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) in coastal wetlands. However, the activities and contributions of AOA and AOB in coastal wetlands have remained largely unknown. Here, we investigated the oxidation capability of AOA and AOB in four types of typical coastal wetlands (paddy, estuary, shallow and reed wetland) in the Bohai region in China using DNA-based stable-isotope probing (DNA-SIP), quantitative PCR and high-throughput sequencing techniques. We found that the community structure of AOB varied substantially, and the AOA structure was more stable across different coastal wetlands. The rate of AOA was 0.12, 0.84, 0.45 and 0.93 μg N g-1 soil d-1 in paddy, estuary, shallow and reed wetlands, and the rate of AOB was 5.61, 10.72, 0.74 and 1.16 μg N g-1 soil d-1, respectively. We found that the contribution of AOA gradually increased from paddy to estuary to shallow wetland and finally to reed wetland, with values of 2.03%, 7.25%, 37.53% and 44.51%, respectively. Our results provide new insight into the mechanisms of the differences in activities and the contributions of AOA and AOB in different coastal wetlands, and our findings may contribute to further understanding of the global nitrogen cycle.},
}
@article {pmid31920997,
year = {2019},
author = {Dekas, AE and Parada, AE and Mayali, X and Fuhrman, JA and Wollard, J and Weber, PK and Pett-Ridge, J},
title = {Characterizing Chemoautotrophy and Heterotrophy in Marine Archaea and Bacteria With Single-Cell Multi-isotope NanoSIP.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {2682},
doi = {10.3389/fmicb.2019.02682},
pmid = {31920997},
issn = {1664-302X},
abstract = {Characterizing and quantifying in situ metabolisms remains both a central goal and challenge for environmental microbiology. Here, we used a single-cell, multi-isotope approach to investigate the anabolic activity of marine microorganisms, with an emphasis on natural populations of Thaumarchaeota. After incubating coastal Pacific Ocean water with 13C-bicarbonate and 15N-amino acids, we used nanoscale secondary ion mass spectrometry (nanoSIMS) to isotopically screen 1,501 individual cells, and 16S rRNA amplicon sequencing to assess community composition. We established isotopic enrichment thresholds for activity and metabolic classification, and with these determined the percentage of anabolically active cells, the distribution of activity across the whole community, and the metabolic lifestyle-chemoautotrophic or heterotrophic-of each cell. Most cells (>90%) were anabolically active during the incubation, and 4-17% were chemoautotrophic. When we inhibited bacteria with antibiotics, the fraction of chemoautotrophic cells detected via nanoSIMS increased, suggesting archaea dominated chemoautotrophy. With fluorescence in situ hybridization coupled to nanoSIMS (FISH-nanoSIMS), we confirmed that most Thaumarchaeota were living chemoautotrophically, while bacteria were not. FISH-nanoSIMS analysis of cells incubated with dual-labeled (13C,15N-) amino acids revealed that most Thaumarchaeota cells assimilated amino-acid-derived nitrogen but not carbon, while bacteria assimilated both. This indicates that some Thaumarchaeota do not assimilate intact amino acids, suggesting intra-phylum heterogeneity in organic carbon utilization, and potentially their use of amino acids for nitrification. Together, our results demonstrate the utility of multi-isotope nanoSIMS analysis for high-throughput metabolic screening, and shed light on the activity and metabolism of uncultured marine archaea and bacteria.},
}
@article {pmid31913316,
year = {2020},
author = {Maus, D and Heinz, J and Schirmack, J and Airo, A and Kounaves, SP and Wagner, D and Schulze-Makuch, D},
title = {Methanogenic Archaea Can Produce Methane in Deliquescence-Driven Mars Analog Environments.},
journal = {Scientific reports},
volume = {10},
number = {1},
pages = {6},
doi = {10.1038/s41598-019-56267-4},
pmid = {31913316},
issn = {2045-2322},
support = {339231//EC | EC Seventh Framework Programm | FP7 Ideas: European Research Council (FP7-IDEAS-ERC - Specific Programme: &quot;Ideas&amp;quot; Implementing the Seventh Framework Programme of the European Community for Research, Technological Development and Demonstration Activities (2007 to 2013))/ ; },
abstract = {The current understanding of the Martian surface indicates that briny environments at the near-surface are temporarily possible, e.g. in the case of the presumably deliquescence-driven Recurring Slope Lineae (RSL). However, whether such dynamic environments are habitable for terrestrial organisms remains poorly understood. This hypothesis was tested by developing a Closed Deliquescence System (CDS) consisting of a mixture of desiccated Martian Regolith Analog (MRA) substrate, salts, and microbial cells, which over the course of days became wetted through deliquescence. The methane produced via metabolic activity for three methanogenic archaea: Methanosarcina mazei, M. barkeri and M. soligelidi, was measured after exposing them to three different MRA substrates using either NaCl or NaClO4 as a hygroscopic salt. Our experiments showed that (1) M. soligelidi rapidly produced methane at 4 °C, (2) M. barkeri produced methane at 28 °C though not at 4 °C, (3) M. mazei was not metabolically reactivated through deliquescence, (4) none of the species produced methane in the presence of perchlorate, and (5) all species were metabolically most active in the phyllosilicate-containing MRA. These results emphasize the importance of the substrate, microbial species, salt, and temperature used in the experiments. Furthermore, we show here for the first time that water provided by deliquescence alone is sufficient to rehydrate methanogenic archaea and to reactivate their metabolism under conditions roughly analogous to the near-subsurface Martian environment.},
}
@article {pmid31900730,
year = {2020},
author = {Cavalier-Smith, T and Chao, EE},
title = {Multidomain ribosomal protein trees and the planctobacterial origin of neomura (eukaryotes, archaebacteria).},
journal = {Protoplasma},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00709-019-01442-7},
pmid = {31900730},
issn = {1615-6102},
support = {NE/E004156/1//Natural Environment Research Council/ ; },
abstract = {Palaeontologically, eubacteria are > 3× older than neomura (eukaryotes, archaebacteria). Cell biology contrasts ancestral eubacterial murein peptidoglycan walls and derived neomuran N-linked glycoprotein coats/walls. Misinterpreting long stems connecting clade neomura to eubacteria on ribosomal sequence trees (plus misinterpreted protein paralogue trees) obscured this historical pattern. Universal multiprotein ribosomal protein (RP) trees, more accurate than rRNA trees, are taxonomically undersampled. To reduce contradictions with genically richer eukaryote trees and improve eubacterial phylogeny, we constructed site-heterogeneous and maximum-likelihood universal three-domain, two-domain, and single-domain trees for 143 eukaryotes (branching now congruent with 187-protein trees), 60 archaebacteria, and 151 taxonomically representative eubacteria, using 51 and 26 RPs. Site-heterogeneous trees greatly improve eubacterial phylogeny and higher classification, e.g. showing gracilicute monophyly, that many 'rDNA-phyla' belong in Proteobacteria, and reveal robust new phyla Synthermota and Aquithermota. Monoderm Posibacteria and Mollicutes (two separate wall losses) are both polyphyletic: multiple outer membrane losses in Endobacteria occurred separately from Actinobacteria; neither phylum is related to Chloroflexi, the most divergent prokaryotes, which originated photosynthesis (new model proposed). RP trees support an eozoan root for eukaryotes and are consistent with archaebacteria being their sisters and rooted between Filarchaeota (=Proteoarchaeota, including 'Asgardia') and Euryarchaeota sensu-lato (including ultrasimplified 'DPANN' whose long branches often distort trees). Two-domain trees group eukaryotes within Planctobacteria, and archaebacteria with Planctobacteria/Sphingobacteria. Integrated molecular/palaeontological evidence favours negibacterial ancestors for neomura and all life. Unique presence of key pre-neomuran characters favours Planctobacteria only as ancestral to neomura, which apparently arose by coevolutionary repercussions (explained here in detail, including RP replacement) of simultaneous outer membrane and murein loss. Planctobacterial C-1 methanotrophic enzymes are likely ancestral to archaebacterial methanogenesis and β-propeller-α-solenoid proteins to eukaryotic vesicle coats, nuclear-pore-complexes, and intraciliary transport. Planctobacterial chaperone-independent 4/5-protofilament microtubules and MamK actin-ancestors prepared for eukaryote intracellular motility, mitosis, cytokinesis, and phagocytosis. We refute numerous wrong ideas about the universal tree.},
}
@article {pmid31889259,
year = {2020},
author = {Knüppel, R and Fenk, M and Jüttner, M and Ferreira-Cerca, S},
title = {In Vivo RNA Chemical Footprinting Analysis in Archaea.},
journal = {Methods in molecular biology (Clifton, N.J.)},
volume = {2106},
number = {},
pages = {193-208},
doi = {10.1007/978-1-0716-0231-7_12},
pmid = {31889259},
issn = {1940-6029},
abstract = {RNA structural conformation and dynamics govern the functional properties of all RNA/RNP. Accordingly, defining changes of RNA structure and dynamics in various conditions may provide detailed insight into how RNA structural properties regulate the function of RNA/RNP. Traditional chemical footprinting analysis using chemical modifiers allows to sample the dynamics and conformation landscape of diverse RNA/RNP. However, many chemical modifiers are limited in their capacity to provide unbiased information reflecting the in vivo RNA/RNP structural landscape. In the recent years, the development of selective-2'-hydroxyl acylation analyzed by primer extension (SHAPE) methodology that uses powerful new chemical modifiers has significantly improved in vitro and in vivo structural probing of secondary and tertiary interactions of diverse RNA species at the single nucleotide level.Although the original discovery of Archaea as an independent domain of life is intimately linked to the technological development of RNA analysis, our understanding of in vivo RNA structural conformation and dynamics in this domain of life remains scarce.This protocol describes the in vivo use of SHAPE chemistry in two evolutionary divergent model Archaea, Sulfolobus acidocaldarius and Haloferax volcanii.},
}
@article {pmid31884971,
year = {2019},
author = {Coutinho, FH and Edwards, RA and Rodríguez-Valera, F},
title = {Charting the diversity of uncultured viruses of Archaea and Bacteria.},
journal = {BMC biology},
volume = {17},
number = {1},
pages = {109},
doi = {10.1186/s12915-019-0723-8},
pmid = {31884971},
issn = {1741-7007},
support = {APOSTD/2018/186//Conselleria d'Educació, Investigació, Cultura i Esport/ ; GL2016-76273-P//Ministerio de Economía y Competitividad/ ; CGL2015-71523-REDC//Ministerio de Economía y Competitividad/ ; },
abstract = {BACKGROUND: Viruses of Archaea and Bacteria are among the most abundant and diverse biological entities on Earth. Unraveling their biodiversity has been challenging due to methodological limitations. Recent advances in culture-independent techniques, such as metagenomics, shed light on the unknown viral diversity, revealing thousands of new viral nucleotide sequences at an unprecedented scale. However, these novel sequences have not been properly classified and the evolutionary associations between them were not resolved.<br><br>RESULTS: Here, we performed phylogenomic analysis of nearly 200,000 viral nucleotide sequences to establish GL-UVAB: Genomic Lineages of Uncultured Viruses of Archaea and Bacteria. The pan-genome content of the identified lineages shed light on some of their infection strategies, potential to modulate host physiology, and mechanisms to escape host resistance systems. Furthermore, using GL-UVAB as a reference database for annotating metagenomes revealed elusive habitat distribution patterns of viral lineages and environmental drivers of community composition.<br><br>CONCLUSIONS: These findings provide insights about the genomic diversity and ecology of viruses of prokaryotes. The source code used in these analyses is freely available at https://sourceforge.net/projects/gluvab/.},
}
@article {pmid31869713,
year = {2019},
author = {Li, M and Huang, Y and Yang, Y and Wang, H and Hu, L and Zhong, H and He, Z},
title = {Heavy metal ions removed from imitating acid mine drainages with a thermoacidophilic archaea: Acidianus manzaensis YN25.},
journal = {Ecotoxicology and environmental safety},
volume = {190},
number = {},
pages = {110084},
doi = {10.1016/j.ecoenv.2019.110084},
pmid = {31869713},
issn = {1090-2414},
abstract = {Metals in acid mine drainages (AMD) have posed a great threat to environment, and in situ economic environment-friendly remediation technologies need to be developed. Moreover, the effects of acidophiles on biosorption and migrating behaviors of metals in AMD have not been previously reported. In this study, the extremely thermoacidophilic Archaea, Acidianus manzaensis YN25 (A. manzaensis YN25) was used as a bio-adsorbent to adsorb metals (Cu2+, Ni2+, Cd2+ and Zn2+) from acidic solutions which were taken to imitate AMD. The values of their maximum biosorption capacities at both high (1 mM) and low (0.1 mM) metal concentrations followed the order: Cu2+ > Ni2+ > Cd2+ > Zn2+. With the elevations of temperature and pH value, the adsorption amounts of metals increased. The results also indicated that A. manzaensis YN25 had the highest adsorption affinity to Cu2+ in coexisting system of quaternary metals. Acid-base titration data revealed that carboxyl and phosphoryl groups provided adsorption sites for metals via deprotonation. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) further corroborated that amino played an important role in the biosorption process. The fitted Langmuir model illustrated monolayer adsorption occurring on cell surface. The possible adsorption mechanism of A. manzaensis YN25 mainly involved in electrostatic attraction and complexes formation. This study gives a profound insight into the biosorption behavior of heavy metals in acidic solution by thermoacidophilic Archaea and provides a probable novel strategy for in situ remediation of heavy metals pollution in AMD.},
}
@article {pmid31856202,
year = {2019},
author = {Hernandez-Guerrero, R and Galán-Vásquez, E and Pérez-Rueda, E},
title = {The protein architecture in Bacteria and Archaea identifies a set of promiscuous and ancient domains.},
journal = {PloS one},
volume = {14},
number = {12},
pages = {e0226604},
doi = {10.1371/journal.pone.0226604},
pmid = {31856202},
issn = {1932-6203},
abstract = {In this work, we describe a systematic comparative genomic analysis of promiscuous domains in genomes of Bacteria and Archaea. A quantitative measure of domain promiscuity, the weighted domain architecture score (WDAS), was used and applied to 1317 domains in 1320 genomes of Bacteria and Archaea. A functional analysis associated with the WDAS per genome showed that 18 of 50 functional categories were identified as significantly enriched in the promiscuous domains; in particular, small-molecule binding domains, transferases domains, DNA binding domains (transcription factors), and signal transduction domains were identified as promiscuous. In contrast, non-promiscuous domains were identified as associated with 6 of 50 functional categories, and the category Function unknown was enriched. In addition, the WDASs of 52 domains correlated with genome size, i.e., WDAS values decreased as the genome size increased, suggesting that the number of combinations at larger domains increases, including domains in the superfamilies Winged helix-turn-helix and P-loop-containing nucleoside triphosphate hydrolases. Finally, based on classification of the domains according to their ancestry, we determined that the set of 52 promiscuous domains are also ancient and abundant among all the genomes, in contrast to the non-promiscuous domains. In summary, we consider that the association between these two classes of protein domains (promiscuous and non-promiscuous) provides bacterial and archaeal cells with the ability to respond to diverse environmental challenges.},
}
@article {pmid31854886,
year = {2019},
author = {Bao, QL and Wang, FH and Bao, WK and Huang, YZ},
title = {[Effects of Rice Straw Addition on Methanogenic Archaea and Bacteria in Two Paddy Soils].},
journal = {Huan jing ke xue= Huanjing kexue},
volume = {40},
number = {9},
pages = {4202-4212},
doi = {10.13227/j.hjkx.201901195},
pmid = {31854886},
issn = {0250-3301},
abstract = {Rice straw (RS) returning has an important effect on CH4 emission in rice paddy soil. In the present study, two paddy soil types from Jiangxi (JX) and Guangdong (GD), respectively, with different amounts of added RS were incubated through microcosmic anaerobic incubation experiments to investigate the responses of methanogenic archaea and bacteria communities after relatively long-term incubation. The different amounts of added RS affected methanogenic archaea community structures in the JX soil to some extent but did not affect the GD soil. The mcrA gene copy number increased with an increase in RS amount in both soils. Under the same amount of RS, the copy number of this gene in the JX soil was greater than that in the GD soil. In addition, significant positive correlations were shown between the RS amount and the copy number of the mcrA gene, and the response of the copy number was more sensitive to the RS amount in the JX soil. Obvious differences in methanogenic archaea community structures were shown between two soils. Methanosarcinaceae, Methanocellaceae, Methanomicrobiaceae, Methanobacteriaceae, and unknown microorganism (494 bp) were detected in the JX soil, and Methanobacteriaceae, Methanosarcinaceae, and Methanocellaceae were observed in the GD soil. The bacterial communities exhibited obvious differences between the two soil types after 180 days of incubation. The bacterial diversity in the GD soil was higher than that in the JX soil, although the amounts of dominant bacteria in the JX soil, including Bacillus, Desulfovirgula, Thermosporothrix, Acidobacteria/Gp1, Acidobacteria/Gp3, and Ktedonobacter, were higher than those of the GD soil, including Longilinea, Acidobacteria/Gp6, Bellilinea, and Thermosporothrix. RS application promoted the growth of methanogenic archaea as important substrates. Moreover, different structures of methanogens and bacteria were shown between the two soil types after relatively long-term incubation.},
}
@article {pmid31854584,
year = {2019},
author = {Guo, JL and Liu, Y and Wei, WX and Ge, TD and Wang, GJ},
title = {[Impact of Dicyandiamide (DCD) and 3,4-Dimethylpyrazole Phosphate (DMPP) on Ammonia-oxidizing Bacteria and Archaea in a Vegetable Planting Soil].},
journal = {Huan jing ke xue= Huanjing kexue},
volume = {40},
number = {11},
pages = {5142-5150},
doi = {10.13227/j.hjkx.201902031},
pmid = {31854584},
issn = {0250-3301},
abstract = {Nitrification inhibitors (NIs) dicyandiamide (DCD) and 3,4-dimethylpyrazole phosphate (DMPP) showed significant effects in the inhibition of nitrification and the improvement of the utilization efficiency of nitrogen fertilizer in agricultural soils. However, the effects of different NIs on ammonia-oxidizing bacteria (AOB) and archaea (AOA) is still unclear. To verify the inhibitory effect of DCD and DMPP on AOB and AOA, a pot experiment was performed, including Urea, Urea+DCD, and Urea+DMPP treatments. The dynamics of NH4+-N and NO3--N and nitrification potential among different treatments were measured. In addition, real-time PCR and high-throughput sequencing approaches were applied to investigate the changes in the AOB and AOA population abundance and composition. The results revealed that the concentrations of NH4+-N in Urea+DCD and Urea+DMPP treatments were 213% and 675% higher than that in the CK treatment, respectively. However, the concentrations of NO3--N and the nitrification potentials were 13.3% and 37.2%, and 20.4% and 82.4% lower than that in CK treatment, respectively; Furthermore, the copy numbers of the bacterial and archaeal amoA gene were 51.2% and 56.5%, and 6.0% and 27.0% lower than that in the CK treatment, respectively. However, the diversity indexes of AOB and AOA communities, including evenness and richness, exhibited no significant differences after addition of DCD and DMPP. The nork-environmental-samples, unclassified-Nitrosomonadaceae, unclassified-Bacteria, and Nitrosospira, were the predominant genera of the AOB community. The no rank-Crenarchaeota, no rank-environmental-samples and Nitrososphaera were the predominant groups in the AOA community. Summarily, application of DCD and DMPP significantly delayed the transformation of NH4+-N, decreased the formation of NO3--N, inhibited the abundance and changed the composition of AOB and AOA communities. DMPP had a stronger inhibitory effect on nitrification, and on AOB and AOA than DCD. Therefore, compared with DCD, DMPP had a better application prospect regarding the improvement of the nitrogen utilization efficiency in vegetable soil.},
}
@article {pmid31836857,
year = {2019},
author = {Gribaldo, S and Brochier-Armanet, C},
title = {Evolutionary relationships between archaea and eukaryotes.},
journal = {Nature ecology &amp; evolution},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41559-019-1073-1},
pmid = {31836857},
issn = {2397-334X},
}
@article {pmid31828323,
year = {2019},
author = {Jüttner, M and Weiß, M and Ostheimer, N and Reglin, C and Kern, M and Knüppel, R and Ferreira-Cerca, S},
title = {A versatile cis-acting element reporter system to study the function, maturation and stability of ribosomal RNA mutants in archaea.},
journal = {Nucleic acids research},
volume = {},
number = {},
pages = {},
doi = {10.1093/nar/gkz1156},
pmid = {31828323},
issn = {1362-4962},
abstract = {General molecular principles of ribosome biogenesis have been well explored in bacteria and eukaryotes. Collectively, these studies have revealed important functional differences and few similarities between these processes. Phylogenetic studies suggest that the information processing machineries from archaea and eukaryotes are evolutionary more closely related than their bacterial counterparts. These observations raise the question of how ribosome synthesis in archaea may proceed in vivo. In this study, we describe a versatile plasmid-based cis-acting reporter system allowing to analyze in vivo the consequences of ribosomal RNA mutations in the model archaeon Haloferax volcanii. Applying this system, we provide evidence that the bulge-helix-bulge motif enclosed within the ribosomal RNA processing stems is required for the formation of archaeal-specific circular-pre-rRNA intermediates and mature rRNAs. In addition, we have collected evidences suggesting functional coordination of the early steps of ribosome synthesis in H. volcanii. Together our investigation describes a versatile platform allowing to generate and functionally analyze the fate of diverse rRNA variants, thereby paving the way to better understand the cis-acting molecular determinants necessary for archaeal ribosome synthesis, maturation, stability and function.},
}
@article {pmid31827386,
year = {2019},
author = {Zheng, P and Wang, C and Zhang, X and Gong, J},
title = {Community Structure and Abundance of Archaea in a Zostera marina Meadow: A Comparison between Seagrass-Colonized and Bare Sediment Sites.},
journal = {Archaea (Vancouver, B.C.)},
volume = {2019},
number = {},
pages = {5108012},
doi = {10.1155/2019/5108012},
pmid = {31827386},
issn = {1472-3654},
abstract = {Seagrass colonization alters sediment physicochemical properties by depositing seagrass fibers and releasing organic carbon and oxygen from the roots. How this seagrass colonization-induced spatial heterogeneity affects archaeal community structure and abundance remains unclear. In this study, we investigated archaeal abundance, diversity, and composition in both vegetated and adjacent bare surface sediments of a Zostera marina meadow. High-throughput sequencing of 16S rDNA showed that Woesearchaeota, Bathyarchaeota, and Thaumarchaeota were the most abundant phyla across all samples, accounting for approximately 42%, 21%, and 17% of the total archaeal communities, respectively. In terms of relative abundance, Woesearchaeota and Bathyarchaeota were not significantly different between these two niches; however, specific subclades (Woese-3, Woese-21, Bathy-6, Bathy-18) were significantly enriched in vegetated sediments (P < 0.05), while Thaumarchaeota was favored in unvegetated sites (P = 0.02). The quantification of archaeal 16S rRNA genes showed that the absolute abundance of the whole archaeal community, Bathyarchaeota, and Woese-3, Woese-10, Woese-13, and Woese-21 was significantly more abundant in vegetated sediments than in bare sediments (P < 0.05). Our study expands the available knowledge of the distribution patterns and niche preferences of archaea in seagrass systems, especially for the different subclades of Woesearchaeota and Bathyarchaeota, in terms of both relative proportions and absolute quantities.},
}
@article {pmid31819085,
year = {2019},
author = {Togo, AH and Grine, G and Khelaifia, S and des Robert, C and Brevaut, V and Caputo, A and Baptiste, E and Bonnet, M and Levasseur, A and Drancourt, M and Million, M and Raoult, D},
title = {Culture of Methanogenic Archaea from Human Colostrum and Milk.},
journal = {Scientific reports},
volume = {9},
number = {1},
pages = {18653},
doi = {10.1038/s41598-019-54759-x},
pmid = {31819085},
issn = {2045-2322},
abstract = {Archaeal sequences have been detected in human colostrum and milk, but no studies have determined whether living archaea are present in either of these fluids. Methanogenic archaea are neglected since they are not detected by usual molecular and culture methods. By using improved DNA detection protocols and microbial culture techniques associated with antioxidants previously developed in our center, we investigated the presence of methanogenic archaea using culture and specific Methanobrevibacter smithii and Methanobrevibacter oralis real-time PCR in human colostrum and milk. M. smithii was isolated from 3 colostrum and 5 milk (day 10) samples. M. oralis was isolated from 1 milk sample. For 2 strains, the genome was sequenced, and the rhizome was similar to that of strains previously isolated from the human mouth and gut. M. smithii was detected in the colostrum or milk of 5/13 (38%) and 37/127 (29%) mothers by culture and qPCR, respectively. The different distribution of maternal body mass index according to the detection of M. smithii suggested an association with maternal metabolic phenotype. M. oralis was not detected by molecular methods. Our results suggest that breastfeeding may contribute to the vertical transmission of these microorganisms and may be essential to seed the infant's microbiota with these neglected critical commensals from the first hour of life.},
}
@article {pmid31801875,
year = {2019},
author = {Prakash, D and Iyer, PR and Suharti, S and Walters, KA and Santiago-Martinez, MG and Golbeck, JH and Murakami, KS and Ferry, JG},
title = {Structure and function of an unusual flavodoxin from the domain Archaea.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {},
number = {},
pages = {},
doi = {10.1073/pnas.1908578116},
pmid = {31801875},
issn = {1091-6490},
abstract = {Flavodoxins, electron transfer proteins essential for diverse metabolisms in microbes from the domain Bacteria, are extensively characterized. Remarkably, although genomic annotations of flavodoxins are widespread in microbes from the domain Archaea, none have been isolated and characterized. Herein is described the structural, biochemical, and physiological characterization of an unusual flavodoxin (FldA) from Methanosarcina acetivorans, an acetate-utilizing methane-producing microbe of the domain Archaea In contrast to all flavodoxins, FldA is homodimeric, markedly less acidic, and stabilizes an anionic semiquinone. The crystal structure reveals an flavin mononucleotide (FMN) binding site unique from all other flavodoxins that provides a rationale for stabilization of the anionic semiquinone and a remarkably low reduction potentials for both the oxidized/semiquinone (-301 mV) and semiquinone/hydroquinone couples (-464 mV). FldA is up-regulated in acetate-grown versus methanol-grown cells and shown here to substitute for ferredoxin in mediating the transfer of low potential electrons from the carbonyl of acetate to the membrane-bound electron transport chain that generates ion gradients driving ATP synthesis. FldA offers potential advantages over ferredoxin by (i) sparing iron for abundant iron-sulfur proteins essential for acetotrophic growth and (ii) resilience to oxidative damage.},
}
@article {pmid31792218,
year = {2019},
author = {Zhu, Q and Mai, U and Pfeiffer, W and Janssen, S and Asnicar, F and Sanders, JG and Belda-Ferre, P and Al-Ghalith, GA and Kopylova, E and McDonald, D and Kosciolek, T and Yin, JB and Huang, S and Salam, N and Jiao, JY and Wu, Z and Xu, ZZ and Cantrell, K and Yang, Y and Sayyari, E and Rabiee, M and Morton, JT and Podell, S and Knights, D and Li, WJ and Huttenhower, C and Segata, N and Smarr, L and Mirarab, S and Knight, R},
title = {Phylogenomics of 10,575 genomes reveals evolutionary proximity between domains Bacteria and Archaea.},
journal = {Nature communications},
volume = {10},
number = {1},
pages = {5477},
doi = {10.1038/s41467-019-13443-4},
pmid = {31792218},
issn = {2041-1723},
support = {BIO150043//National Science Foundation (NSF)/ ; },
abstract = {Rapid growth of genome data provides opportunities for updating microbial evolutionary relationships, but this is challenged by the discordant evolution of individual genes. Here we build a reference phylogeny of 10,575 evenly-sampled bacterial and archaeal genomes, based on a comprehensive set of 381 markers, using multiple strategies. Our trees indicate remarkably closer evolutionary proximity between Archaea and Bacteria than previous estimates that were limited to fewer &quot;core&quot; genes, such as the ribosomal proteins. The robustness of the results was tested with respect to several variables, including taxon and site sampling, amino acid substitution heterogeneity and saturation, non-vertical evolution, and the impact of exclusion of candidate phyla radiation (CPR) taxa. Our results provide an updated view of domain-level relationships.},
}
@article {pmid31787176,
year = {2019},
author = {Islam, GM and Vi, P and Gilbride, KA},
title = {Functional relationship between ammonia-oxidizing bacteria and ammonia-oxidizing archaea populations in the secondary treatment system of a full-scale municipal wastewater treatment plant.},
journal = {Journal of environmental sciences (China)},
volume = {86},
number = {},
pages = {120-130},
doi = {10.1016/j.jes.2019.04.031},
pmid = {31787176},
issn = {1001-0742},
abstract = {The abundance of ammonia-oxidizing bacteria and archaea and their amoA genes from the aerobic activated sludge tanks, recycled sludge and anaerobic digesters of a full-scale wastewater treatment plant (WWTP) was determined. Polymerase chain reaction and denaturing gradient gel electrophoresis were used to generate diversity profiles, which showed that each population had a consistent profile although the abundance of individual members varied. In the aerobic tanks, the ammonia-oxidizing bacterial (AOB) population was more than 350 times more abundant than the ammonia-oxidizing archaeal (AOA) population, however in the digesters, the AOA population was more than 10 times more abundant. Measuring the activity of the amoA gene expression of the two populations using RT-PCR also showed that the AOA amoA gene was more active in the digesters than in the activated sludge tanks. Using batch reactors and ddPCR, amoA activity could be measured and it was found that when the AOB amoA activity was inhibited in the anoxic reactors, the expression of the AOA amoA gene increased fourfold. This suggests that these two populations may have a cooperative relationship for the oxidation of ammonia.},
}
@article {pmid31754204,
year = {2019},
author = {Rinke, C and Rubino, F and Messer, LF and Youssef, N and Parks, DH and Chuvochina, M and Brown, M and Jeffries, T and Tyson, GW and Seymour, JR and Hugenholtz, P},
title = {Correction: A phylogenomic and ecological analysis of the globally abundant Marine Group II archaea (Ca. Poseidoniales ord. nov.).},
journal = {The ISME journal},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41396-019-0556-z},
pmid = {31754204},
issn = {1751-7370},
abstract = {An amendment to this paper has been published and can be accessed via a link at the top of the paper.},
}
@article {pmid31745137,
year = {2019},
author = {Paula, FS and Chin, JP and Schnürer, A and Müller, B and Manesiotis, P and Waters, N and Macintosh, KA and Quinn, JP and Connolly, J and Abram, F and McGrath, JW and O'Flaherty, V},
title = {The potential for polyphosphate metabolism in Archaea and anaerobic polyphosphate formation in Methanosarcina mazei.},
journal = {Scientific reports},
volume = {9},
number = {1},
pages = {17101},
doi = {10.1038/s41598-019-53168-4},
pmid = {31745137},
issn = {2045-2322},
abstract = {Inorganic polyphosphate (polyP) is ubiquitous across all forms of life, but the study of its metabolism has been mainly confined to bacteria and yeasts. Few reports detail the presence and accumulation of polyP in Archaea, and little information is available on its functions and regulation. Here, we report that homologs of bacterial polyP metabolism proteins are present across the major taxa in the Archaea, suggesting that archaeal populations may have a greater contribution to global phosphorus cycling than has previously been recognised. We also demonstrate that polyP accumulation can be induced under strictly anaerobic conditions, in response to changes in phosphate (Pi) availability, i.e. Pi starvation, followed by incubation in Pi replete media (overplus), in cells of the methanogenic archaeon Methanosarcina mazei. Pi-starved M. mazei cells increased transcript abundance of the alkaline phosphatase (phoA) gene and of the high-affinity phosphate transport (pstSCAB-phoU) operon: no increase in polyphosphate kinase 1 (ppk1) transcript abundance was observed. Subsequent incubation of Pi-starved M. mazei cells under Pi replete conditions, led to a 237% increase in intracellular polyphosphate content and a > 5.7-fold increase in ppk1 gene transcripts. Ppk1 expression in M. mazei thus appears not to be under classical phosphate starvation control.},
}
@article {pmid31739075,
year = {2019},
author = {Dame-Teixeira, N and de Cena, JA and Côrtes, DA and Belmok, A and Dos Anjos Borges, LG and Marconatto, L and Giongo, A and Kyaw, CM},
title = {Presence of Archaea in dental caries biofilms.},
journal = {Archives of oral biology},
volume = {110},
number = {},
pages = {104606},
doi = {10.1016/j.archoralbio.2019.104606},
pmid = {31739075},
issn = {1879-1506},
abstract = {OBJECTIVE: Although the prevalence and functions associated with members of Bacteria are well known in dental caries, the role of Archaea in cariogenic biofilms has not been studied yet.<br><br>DESIGN: To detect the presence of Archaea in dental caries, a triplicate of carious dentine samples and duplicate of supragingival biofilms were collected, total microbial DNA was extracted and the composition of the microbiota was investigated. Total DNA was submitted to 16S rRNA gene amplification using universal prokaryotic primers; amplicons were sequenced by high-throughput DNA sequencing. As a second strategy to detect Archaea, a representative sample of caries was chosen and other PCR reactions were performed using specific primers targeting the archaeal 16S rRNA gene; amplicons were cloned and sequenced. Annotation of sequences was performed using SILVA database and the relative abundance of genus level OTUs was calculated.<br><br>RESULTS: The high-throughput sequencing method detected archaeal sequences in all samples (identified as group I.1c of the phylum Thaumarchaeota), although in a very low abundance (≤0.03 % of the total sequences). For the second strategy, 14 archaeal clones were detected, with an OTU affiliated to Methanocella clade, and another one affiliated to group I.1b of the phylum Thaumarchaeota.<br><br>CONCLUSIONS: Archaeal sequences were detected in dental caries and biofilms from surfaces without caries lesions. DNA sequences of Thaumarchaeota were also identified, showing that overall archaeal diversity in the human oral cavity could be currently underestimated and not restricted to methanogens.},
}
@article {pmid31712737,
year = {2019},
author = {Brewer, TE and Albertsen, M and Edwards, A and Kirkegaard, RH and Rocha, EPC and Fierer, N},
title = {Unlinked rRNA genes are widespread among bacteria and archaea.},
journal = {The ISME journal},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41396-019-0552-3},
pmid = {31712737},
issn = {1751-7370},
support = {15510//Villum Fonden (Villum Foundation)/ ; RF-2017-652\2//Leverhulme Trust/ ; EAR1331828//National Science Foundation (NSF)/ ; },
abstract = {Ribosomes are essential to cellular life and the genes for their RNA components are the most conserved and transcribed genes in bacteria and archaea. Ribosomal RNA genes are typically organized into a single operon, an arrangement thought to facilitate gene regulation. In reality, some bacteria and archaea do not share this canonical rRNA arrangement-their 16S and 23S rRNA genes are separated across the genome and referred to as &quot;unlinked&quot;. This rearrangement has previously been treated as an anomaly or a byproduct of genome degradation in intracellular bacteria. Here, we leverage complete genome and long-read metagenomic data to show that unlinked 16S and 23S rRNA genes are more common than previously thought. Unlinked rRNA genes occur in many phyla, most significantly within Deinococcus-Thermus, Chloroflexi, and Planctomycetes, and occur in differential frequencies across natural environments. We found that up to 41% of rRNA genes in soil were unlinked, in contrast to the human gut, where all sequenced rRNA genes were linked. The frequency of unlinked rRNA genes may reflect meaningful life history traits, as they tend to be associated with a mix of slow-growing free-living species and intracellular species. We speculate that unlinked rRNA genes may confer selective advantages in some environments, though the specific nature of these advantages remains undetermined and worthy of further investigation. More generally, the prevalence of unlinked rRNA genes in poorly-studied taxa serves as a reminder that paradigms derived from model organisms do not necessarily extend to the broader diversity of bacteria and archaea.},
}
@article {pmid31712277,
year = {2019},
author = {Johnsen, U and Sutter, JM and Reinhardt, A and Pickl, A and Wang, R and Xiang, H and Schönheit, P},
title = {D-Ribose catabolism in archaea: Discovery of a novel oxidative pathway in Haloarcula species.},
journal = {Journal of bacteriology},
volume = {},
number = {},
pages = {},
doi = {10.1128/JB.00608-19},
pmid = {31712277},
issn = {1098-5530},
abstract = {The Haloarcula species H. marismortui and H. hispanica were found to grow on D-ribose, D-xylose and L-arabinose. Here we report the discovery of a novel promiscuous oxidative pathway of pentose degradation based on genome analyses, identification and characterization of enzymes, transcriptional analyses and growth experiments with knock out mutants. Together, the data indicate that in Haloarcula D-ribose, D-xylose and L-arabinose were degraded to α-ketoglutarate involving the following enzymes: (i) a promiscuous pentose dehydrogenase catalyzed the oxidation of D-ribose, D-xylose and L-arabinose. (ii) a promiscuous pentonolactonase is involved in the hydrolysis of ribonolactone, xylonolactone and arabinolactone. (iii) a highly specific dehydratase, ribonate dehydratase, catalyzed the dehydration of ribonate, and a second enzyme, a promiscuous xylonate/gluconate dehydratase, was involved in the conversion of xylonate, arabinonate and gluconate. Phylogenetic analyses indicated that the highly specific ribonate dehydratase constitutes a novel sugar acid dehydratase family within the enolase superfamily. (iv) Finally, 2-keto-3-deoxypentonate dehydratase and α-ketoglutarate semialdehyde dehydrogenase catalyzed the conversion of 2-keto-3-deoxypentanonate to α-ketoglutarate via α-ketoglutarate semialdehyde.We conclude that the expanded substrate specificity of the pentose dehydrogenase and pentonolactonase towards D-ribose and ribonolactone, respectively and the presence of a highly specific ribonate dehydratase are prerequisites of the oxidative degradation of D-ribose in Haloarcula This is the first characterization of an oxidative degradation pathway of D-ribose to α-ketoglutarate in archaea.Importance The utilization and degradation of D-ribose in archaea, the third domain of life, has not been analyzed so far. We show that Haloarcula species utilize D-ribose which is degraded to α-ketoglutarate via a novel oxidative pathway. Evidence is presented that the oxidative degradation of D-ribose involves novel promiscuous enzymes, pentose dehydrogenase and pentonolactonase, and a novel sugar acid dehydratase highly specific for ribonate. This is the first report of an oxidative degradation pathway of D-ribose in archaea, which differs from the canonical non-oxidative pathway of D-ribose degradation reported for most bacteria. The data contribute to our understanding of the unusual sugar degradation pathways and enzymes in archaea.},
}
@article {pmid31709520,
year = {2019},
author = {Zhao, C and Lyu, Z and Long, F and Akinyemi, T and Manakongtreecheep, K and Söll, D and Whitman, WB and Vinyard, DJ and Liu, Y},
title = {The Nbp35/ApbC homolog acts as a nonessential [4Fe-4S] transfer protein in methanogenic archaea.},
journal = {FEBS letters},
volume = {},
number = {},
pages = {},
doi = {10.1002/1873-3468.13673},
pmid = {31709520},
issn = {1873-3468},
abstract = {The Nbp35/Cfd1/ApbC protein homologs have been identified in all three domains of life. In eukaryotes, the Nbp35/Cfd1 heterocomplex is an essential Fe-S cluster assembly scaffold required for the maturation of Fe-S proteins in the cytosol and nucleus, whereas the bacterial ApbC is an Fe-S cluster transfer protein only involved in the maturation of a specific target protein. Here, we show that the Nbp35/ApbC homolog MMP0704 purified from its native archaeal host Methanococcus maripaludis contains a [4Fe-4S] cluster that can be transferred to a [4Fe-4S] apo-protein. Deletion of mmp0704 from M. maripaludis does not cause growth deficiency under our tested conditions. Our data indicate that Nbp35/ApbC is a nonessential [4Fe-4S] cluster transfer protein in methanogenic archaea.},
}
@article {pmid31705614,
year = {2019},
author = {Kubatova, N and Pyper, DJ and Jonker, HRA and Saxena, K and Remmel, L and Richter, C and Brantl, S and Evguenieva-Hackenberg, E and Hess, W and Klug, G and Marchfelder, A and Soppa, J and Streit, W and Mayzel, M and Orekhov, VY and Fuxreiter, M and Schmitz-Streit, R and Schwalbe, H},
title = {Rapid biophysical characterization and NMR structural analysis of small proteins from bacteria and archaea.},
journal = {Chembiochem : a European journal of chemical biology},
volume = {},
number = {},
pages = {},
doi = {10.1002/cbic.201900677},
pmid = {31705614},
issn = {1439-7633},
abstract = {Proteins encoded by small open reading frames (sORFs) have a widespread occurrence in diverse microorganisms and can be of high functional importance. However, due to annotation biases and their technically challenging direct detection, these small proteins were overlooked for a long time and are becoming discovered only recently. The currently rapidly growing number of such proteins requires efficient methods to investigate their structure-function-relation. Here, we present a method for fast determination of the conformational properties of small proteins. Their small size makes them perfectly amenable for solution-state NMR spectroscopy. NMR spectroscopy can provide detailed information about their conformational states (folded, partially folded and unstructured). In the context of the priority program on small proteins funded by the German research foundation (SPP2002), we have investigated 27 small proteins from nine different bacterial and archaeal organisms. We found that most of these small proteins are unstructured or partially folded. Bioinformatics tools predict that some of these unstructured proteins can potentially fold upon complex formation. We further describe a protocol for fast NMR structure elucidation for those small proteins that adopt a persistently folded structure by implementation of new NMR technologies including automated resonance assignment and non-uniform sampling in combination with targeted acquisition.},
}
@article {pmid31704973,
year = {2019},
author = {Chénard, C and Wijaya, W and Vaulot, D and Lopes Dos Santos, A and Martin, P and Kaur, A and Lauro, FM},
title = {Temporal and spatial dynamics of Bacteria, Archaea and protists in equatorial coastal waters.},
journal = {Scientific reports},
volume = {9},
number = {1},
pages = {16390},
doi = {10.1038/s41598-019-52648-x},
pmid = {31704973},
issn = {2045-2322},
support = {MSRDP-P13//National Research Foundation Singapore (National Research Foundation-Prime Minister&amp;apos;s office, Republic of Singapore)/ ; },
abstract = {Singapore, an equatorial island in South East Asia, is influenced by a bi-annual reversal of wind directions which defines two monsoon seasons. We characterized the dynamics of the microbial communities of Singapore coastal waters by collecting monthly samples between February 2017 and July 2018 at four sites located across two straits with different trophic status, and sequencing the V6-V8 region of the small sub-unit ribosomal RNA gene (rRNA gene) of Bacteria, Archaea, and Eukaryota. Johor Strait, which is subjected to wider environmental fluctuations from anthropogenic activities, presented a higher abundance of copiotrophic microbes, including Cellvibrionales and Rhodobacterales. The mesotrophic Singapore Strait, where the seasonal variability is caused by changes in the oceanographic conditions, harboured a higher proportion of typically marine microbe groups such as Synechococcales, Nitrosupumilales, SAR11, SAR86, Marine Group II Archaea and Radiolaria. In addition, we observed seasonal variability of the microbial communities in the Singapore Strait, which was possibly influenced by the alternating monsoon regime, while no seasonal pattern was detected in the Johor Strait.},
}
@article {pmid31690001,
year = {2019},
author = {Mukhtar, H and Lin, YP and Lin, CM and Lin, YR},
title = {Relative Abundance of Ammonia Oxidizing Archaea and Bacteria Influences Soil Nitrification Responses to Temperature.},
journal = {Microorganisms},
volume = {7},
number = {11},
pages = {},
doi = {10.3390/microorganisms7110526},
pmid = {31690001},
issn = {2076-2607},
abstract = {Ammonia oxidizing archaea (AOA) and bacteria (AOB) are thought to contribute differently to soil nitrification, yet the extent to which their relative abundances influence the temperature response of nitrification is poorly understood. Here, we investigated the impact of different AOA to AOB ratios on soil nitrification potential (NP) across a temperature gradient from 4 °C to 40 °C in twenty different organic and inorganic fertilized soils. The temperature responses of different relative abundance of ammonia oxidizers for nitrification were modeled using square rate theory (SQRT) and macromolecular rate theory (MMRT) models. We found that the proportional nitrification rates at different temperatures varied among AOA to AOB ratios. Predicted by both models, an optimum temperature (Topt) for nitrification in AOA dominated soils was significantly higher than for soils where AOA and AOB abundances are within the same order of magnitude. Moreover, the change in heat capacity (Δ C P ‡) associated with the temperature dependence of nitrification was positively correlated with Topt and significantly varied among the AOA to AOB ratios. The temperature ranges for NP decreased with increasing AOA abundance for both organic and inorganic fertilized soils. These results challenge the widely accepted approach of comparing NP rates in different soils at a fixed temperature. We conclude that a shift in AOA to AOB ratio in soils exhibits distinguished temperature-dependent characteristics that have an important impact on nitrification responses across the temperature gradient. The proposed approach benefits the accurate discernment of the true contribution of fertilized soils to nitrification for improvement of nitrogen management.},
}
@article {pmid31683078,
year = {2019},
author = {Magdalena, JA and González-Fernández, C},
title = {Archaea inhibition: Strategies for the enhancement of volatile fatty acids production from microalgae.},
journal = {Waste management (New York, N.Y.)},
volume = {102},
number = {},
pages = {222-230},
doi = {10.1016/j.wasman.2019.10.044},
pmid = {31683078},
issn = {1879-2456},
abstract = {In the present study, anaerobic sludge was subjected to thermal and chemical pretreatments to favour VFAs production from a protein-rich waste (i.e. microalgae biomass). Sludge pretreatments have been previously used in hydrogen production; however, information about how they can affect VFAs production from microalgae is still lacking. Thermal pretreatment was studied at: (i) 80 °C for 10 and 30 min; (ii) 120 °C for 10 and 30 min; and (iii) 100 °C for 20 min. 2-bromoethanesulfonate (BES) at 10 mM and 30 mM was used as chemical pretreatment. Besides, a combination of both pretreatment methods (80 °C and 120 °C at 10 mM and 30 mM BES) was also tested. Thermal pretreatment increased organic matter conversions into VFAs (up to 71% COD-VFAs/CODin) when compared to control values (40% in the untreated anaerobic sludge). Acetic acid was the most abundant VFAs at high temperatures (120 °C) and when BES was employed (up to 60% and 40%, respectively, in terms of COD). On the other hand, propionic acid was the most abundant product at low temperatures and in the untreated anaerobic sludge (up to 60% in terms of COD). This research work might set guidelines in order to choose a suitable sludge pretreatment for VFAs production from microalgae.},
}
@article {pmid31681249,
year = {2019},
author = {He, H and Fu, L and Liu, Q and Fu, L and Bi, N and Yang, Z and Zhen, Y},
title = {Community Structure, Abundance and Potential Functions of Bacteria and Archaea in the Sansha Yongle Blue Hole, Xisha, South China Sea.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {2404},
doi = {10.3389/fmicb.2019.02404},
pmid = {31681249},
issn = {1664-302X},
abstract = {The Sansha Yongle Blue Hole is the deepest blue hole in the world and exhibits unique environmental characteristics. In this paper, Illumina sequencing and qPCR analysis were conducted to obtain the microbial information in this special ecosystem. The results showed that the richness and diversity of bacterial communities in the hole was greater than those of archaeal communities, and bacterial and archaeal communities were dominated by Proteobacteria and Euryarchaeota, respectively. Temperature and nitrate concentration significantly contributed to the heterogeneous distribution of major bacterial clades; salinity explained most variations of the archaeal communities, but not significant. A sudden increase of bacterial 16S rRNA, archaeal 16S rRNA, ANAMMOX 16S rRNA, nirS and dsrB gene was noticed from 90 to 100 m in the hole probably due to more phytoplankton at this depth. Sulfur oxidation and nitrate reduction were the most abundant predicted ecological functions in the hole, while lots of archaea were predicted to be involved in aerobic ammonia oxidation and methanogenesis. The co-occurrence network analysis illustrated that a synergistic effect between sulfate reduction and sulfur oxidation, and between nitrogen fixation and denitrification, a certain degree of coupling between sulfur and nitrogen cycle was also observed in the hole. The comparisons of bacterial and archaeal communities between the hole and other caves in the world (or other areas of the South China Sea) suggest that similar conditions are hypothesized to give rise to similar microbial communities, and environmental conditions may contribute significantly to the bacterial and archaeal communities.},
}
@article {pmid31669955,
year = {2019},
author = {Tu, R and Jin, W and Han, SF and Zhou, X and Wang, T and Gao, SH and Wang, Q and Chen, C and Xie, GJ and Wang, Q},
title = {Rapid enrichment and ammonia oxidation performance of ammonia-oxidizing archaea from an urban polluted river of China.},
journal = {Environmental pollution (Barking, Essex : 1987)},
volume = {255},
number = {Pt 2},
pages = {113258},
doi = {10.1016/j.envpol.2019.113258},
pmid = {31669955},
issn = {1873-6424},
abstract = {Ammonia oxidation is the rate-limiting step in nitrification process and dominated by ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA). In the present study, a highly enriched culture of AOA was obtained from urban polluted water in Shahe River, Shenzhen, China. The optimum growth conditions were identified by orthogonal analysis as 37 °C, with pH 7.0 and initial ammonia concentration of 1.0 mM. Under these conditions, the highest abundance of AOA was obtained as 4.6 × 107 copies/ng DNA. Growth of AOA in polluted river water showed significant reduction in ammonia concentration in AOA-enriched cultures without antibiotics after 10 days of incubation, while synchronous increase in nitrate concentration was up to 12.7 mg/L. However, AOA-enriched by antibiotic showed insignificant changes in ammonia or nitrite concentration. This study showed that AOB play an important role in ammonia oxidation of polluted river water, and AOA alone showed insignificant changes in ammonia or nitrite concentrations. Therefore, the ammonia oxidation performance of natural water could not be improved by adding high concentration AOA bacterial liquid.},
}
@article {pmid31666740,
year = {2019},
author = {Belilla, J and Moreira, D and Jardillier, L and Reboul, G and Benzerara, K and López-García, JM and Bertolino, P and López-Archilla, AI and López-García, P},
title = {Hyperdiverse archaea near life limits at the polyextreme geothermal Dallol area.},
journal = {Nature ecology &amp; evolution},
volume = {3},
number = {11},
pages = {1552-1561},
doi = {10.1038/s41559-019-1005-0},
pmid = {31666740},
issn = {2397-334X},
support = {322669//EC | EC Seventh Framework Programm | FP7 Ideas: European Research Council (FP7-IDEAS-ERC - Specific Programme: &quot;Ideas&quot; Implementing the Seventh Framework Programme of the European Community for Research, Technological Development and Demonstration Activities (2007 to 2013))/ ; },
abstract = {Microbial life has adapted to various individual extreme conditions; yet, organisms simultaneously adapted to very low pH, high salt and high temperature are unknown. We combined environmental 16S/18S ribosomal RNA gene metabarcoding, cultural approaches, fluorescence-activated cell sorting, scanning electron microscopy and chemical analyses to study samples along such unique polyextreme gradients in the Dallol-Danakil area in Ethiopia. We identified two physicochemical barriers to life in the presence of surface liquid water defined by (1) high chaotropicity-low water activity in Mg2+/Ca2+-dominated brines and (2) hyperacidity-salt combinations (pH ~0/NaCl-dominated salt saturation). When detected, life was dominated by highly diverse ultrasmall archaea that were widely distributed across phyla with and without previously known halophilic members. We hypothesize that a high cytoplasmic K+-level was an original archaeal adaptation to hyperthermophily, subsequently exapted during several transitions to extreme halophily. We detect active silica encrustment/fossilization of cells but also abiotic biomorphs of varied chemistry. Our work helps circumscribing habitability and calls for cautionary interpretations of morphological biosignatures on Earth and beyond.},
}
@article {pmid31654454,
year = {2019},
author = {Xu, S and Lu, W and Mustafa, MF and Liu, Y and Wang, H},
title = {Presence of diverse nitrate-dependent anaerobic methane oxidizing archaea in sewage sludge.},
journal = {Journal of applied microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/jam.14502},
pmid = {31654454},
issn = {1365-2672},
abstract = {AIM: The aim of this study was to explore the community diversity and abundance of nitrate-dependent anaerobic methane oxidizing archaea, Candidatus Methanoperedens nitroreducens, in sewage sludge from wastewater treatment plants.<br><br>METHODS AND RESULTS: Seasonal sampling of the sewage sludge was carried out from two wastewater treatment plants (WWTPs) located in the northern and southern parts of China. Through amplicon sequencing using our newly designed primers, a large number of Candidatus Methanoperedens nitroreducens-like (M. nitroreducens) archaeal sequences (638,743) were generated. These sequences were assigned into 742 operational protein units (OPUs) at 90% cut-off level and classified as Group B member of M. nitroreducens archaea in the phylogenetic tree. More than 80% of the OPUs were not shared between these two WWTPs, showing the M. nitroreducens-like archaeal community in each WWTP was unique. Quantitative PCR assays also confirmed the presence of M. nitroreducens-like archaea and revealed a higher abundance in autumn and winter than other seasons, indicating that the environmental attributes in these seasons might favor the growth of this archaea. Further redundancy analysis revealed that volatile solid and pH were the significant environmental attributes (p<0.05) in shaping the M. nitroreducens-like archaeal community based on variance inflation factor selection and Monte Carlo permutation test.<br><br>CONCLUSIONS: The results confirmed the presence of diverse M. nitroreducens-like archaea in sewage sludge by using Illumina-based mcrA gene sequencing and quantitative PCR assays.<br><br>The results of this study revealed the ecological characteristics of M. nitroreducens-like archaea in sewage sludge that improved our understanding of nitrate-dependent anaerobic methane oxidation process and may be the basis for future application of M. nitroreducens-like archaea for new nitrogen removal in WWTPs.},
}
@article {pmid31637140,
year = {2019},
author = {Yuan, M and Liu, S and Wang, Z and Wang, L and Xue, B and Zou, H and Tian, G and Cai, J and Peng, Q},
title = {Effects of particle size of ground alfalfa hay on caecal bacteria and archaea populations of rabbits.},
journal = {PeerJ},
volume = {7},
number = {},
pages = {e7910},
doi = {10.7717/peerj.7910},
pmid = {31637140},
issn = {2167-8359},
abstract = {This work was aimed to investigate the effects of the different particle size of ground alfalfa hay on caecal microbial and archeal communities of rabbits. One hundred-twenty New Zealand rabbits (950.3 ± 8.82 g) were allocated into four treatments, with five replicates in each treatment and six rabbits in each replicate. The particle sizes of the alfalfa meal in the four treatment diets were 2,500, 1,000, 100 and 10 µm respectively, while the other ingredients were ground through a 2.5 mm sieve. High-throughput sequencing technology was applied to examine the differences in bacteria and methanogenic archaea diversity in the caecum of the four treatment groups of rabbits. A total of 745,946 bacterial sequences (a mean of 31,081 ± 13,901 sequences per sample) and 539,227 archaeal sequences (a mean of 22,468 ± 2,443 sequences per sample) were recovered from twenty-four caecal samples, and were clustered into 9,953 and 2,246 OTUs respectively. A total of 26 bacterial phyla with 465 genera and three archaeal phyla with 10 genera were identified after taxonomic summarization. Bioinformatic analyses illustrated that Firmicutes (58.69% ∼ 68.50%) and Bacteroidetes (23.96% ∼ 36.05%) were the two most predominant bacterial phyla and Euryarchaeota (over 99.9%) was the most predominant archaeal phyla in the caecum of all rabbits. At genus level, as the particle size of alfalfa decreased from 2,500 to 10 µm, the relative abundances of Ruminococcaceae UCG-014 (P < 0.001) and Lactobacillus (P = 0.043) were increased and Ruminococcaceae UCG-005 (P = 0.012) was increased first and then decreased when the alfalfa particle size decreased, while Lachnospiraceae NK4A136 group (P = 0.016), Ruminococcaceae NK4A214 (P = 0.044), Christensenellaceae R-7 group (P = 0.019), Lachnospiraceae other (Family) (P = 0.011) and Ruminococcaceae UCG-013 (P = 0.021) were decreased. The relative abundance of Methanobrevibacter was increased from 62.48% to 90.40% (P < 0.001), whereas the relative abundance of Methanosphaera was reduced from 35.47% to 8.62% (P < 0.001). In conclusion, as the particle size of alfalfa meal decreased, both the bacterial and archaeal population in the caecum of rabbit experienced alterations, however archaea response earlier than bacteria to the decrease of alfalfa meal particle size.},
}
@article {pmid31618850,
year = {2019},
author = {Lu, Y and Xia, X and Cheung, S and Jing, H and Liu, H},
title = {Differential Distribution and Determinants of Ammonia Oxidizing Archaea Sublineages in the Oxygen Minimum Zone off Costa Rica.},
journal = {Microorganisms},
volume = {7},
number = {10},
pages = {},
doi = {10.3390/microorganisms7100453},
pmid = {31618850},
issn = {2076-2607},
support = {2015CB954003//Ministry of Science and Technology of the People's Republic of China/ ; N-HKUST609/15//Research Grants Council, University Grants Committee/ ; 16128416//Research Grants Council, University Grants Committee/ ; 16101318//Research Grants Council, University Grants Committee/ ; Y8SL031001//CAS Pioneer Hundred Talents Program, the South China Sea Institute of Oceanography/ ; Y9YB021001//CAS Pioneer Hundred Talents Program, the South China Sea Institute of Oceanography/ ; 31971501//National Natural Science Foundation of China/ ; },
abstract = {Ammonia oxidizing archaea (AOA) are microbes that are widely distributed in the ocean that convert ammonia to nitrite for energy acquisition in the presence of oxygen. Recent study has unraveled highly diverse sublineages within the previously defined AOA ecotypes (i.e., water column A (WCA) and water column B (WCB)), although the eco-physiology and environmental determinants of WCB subclades remain largely unclear. In this study, we examined the AOA communities along the water columns (40-3000 m depth) in the Costa Rica Dome (CRD) upwelling region in the eastern tropical North Pacific Ocean. Highly diverse AOA communities that were significantly different from those in oxygenated water layers were observed in the core layer of the oxygen minimum zone (OMZ), where the dissolved oxygen (DO) concentration was < 2μM. Moreover, a number of AOA phylotypes were found to be enriched in the OMZ core. Most of them were negatively correlated with DO and were also detected in other OMZs in the Arabian Sea and Gulf of California, which suggests low oxygen adaptation. This study provided the first insight into the differential niche partitioning and environmental determinants of various subclades within the ecotype WCB. Our results indicated that the ecotype WCB did indeed consist of various sublineages with different eco-physiologies, which should be further explored.},
}
@article {pmid31614851,
year = {2019},
author = {Odelade, KA and Babalola, OO},
title = {Bacteria, Fungi and Archaea Domains in Rhizospheric Soil and Their Effects in Enhancing Agricultural Productivity.},
journal = {International journal of environmental research and public health},
volume = {16},
number = {20},
pages = {},
doi = {10.3390/ijerph16203873},
pmid = {31614851},
issn = {1660-4601},
abstract = {The persistent and undiscriminating application of chemicals as means to improve crop growth, development and yields for several years has become problematic to agricultural sustainability because of the adverse effects these chemicals have on the produce, consumers and beneficial microbes in the ecosystem. Therefore, for agricultural productivity to be sustained there are needs for better and suitable preferences which would be friendly to the ecosystem. The use of microbial metabolites has become an attractive and more feasible preference because they are versatile, degradable and ecofriendly, unlike chemicals. In order to achieve this aim, it is then imperative to explore microbes that are very close to the root of a plant, especially where they are more concentrated and have efficient activities called the rhizosphere. Extensive varieties of bacteria, archaea, fungi and other microbes are found inhabiting the rhizosphere with various interactions with the plant host. Therefore, this review explores various beneficial microbes such as bacteria, fungi and archaea and their roles in the environment in terms of acquisition of nutrients for plants for the purposes of plant growth and health. It also discusses the effect of root exudate on the rhizosphere microbiome and compares the three domains at molecular levels.},
}
@article {pmid31605529,
year = {2019},
author = {Farley, KR and Metcalf, WW},
title = {The streptothricin acetyltransferase (sat) gene as a positive selectable marker for methanogenic archaea.},
journal = {FEMS microbiology letters},
volume = {},
number = {},
pages = {},
doi = {10.1093/femsle/fnz216},
pmid = {31605529},
issn = {1574-6968},
abstract = {A repertoire of sophisticated genetic tools has significantly enhanced studies of Methanosarcina genera, yet the lack of multiple positive selectable markers has limited the types of genetic experiments that can be performed. In this study, we report the development of an additional positive selection system for Methanosarcina that utilizes the antibiotic nourseothricin and the Streptomyces rochei streptothricin acetyltransferase (sat) gene, which may be broadly applicable to other groups of methanogenic archaea. Nourseothricin was found to inhibit growth of four different methanogen species at concentrations ≤ 300 μg/ml in liquid or on solid media. Selection of nourseothricin resistant transformants was possible in two genetically tractable Methanosarcina species, M. acetivorans and M. barkeri, using the sat gene as a positive selectable marker. Additionally the sat marker was useful for constructing a gene deletion mutant strain of M. acetivorans, emphasizing its utility as a second positive selectable marker for genetic analyses of Methanosarcina genera. Interestingly, two human gut-associated methanogens Methanobrevibacter smithii and Methanomassillicoccus luminyensis were more sensitive to nourseothricin than either Methanosarcina species, suggesting the nourseothricin-sat gene pair may provide a robust positive selection system for development of genetic tools in these and other methanogens.},
}
@article {pmid31594929,
year = {2019},
author = {Hua, ZS and Wang, YL and Evans, PN and Qu, YN and Goh, KM and Rao, YZ and Qi, YL and Li, YX and Huang, MJ and Jiao, JY and Chen, YT and Mao, YP and Shu, WS and Hozzein, W and Hedlund, BP and Tyson, GW and Zhang, T and Li, WJ},
title = {Insights into the ecological roles and evolution of methyl-coenzyme M reductase-containing hot spring Archaea.},
journal = {Nature communications},
volume = {10},
number = {1},
pages = {4574},
doi = {10.1038/s41467-019-12574-y},
pmid = {31594929},
issn = {2041-1723},
support = {U1201233//National Natural Science Foundation of China (National Science Foundation of China)/ ; 31370154//National Natural Science Foundation of China (National Science Foundation of China)/ ; 2015FY110100//Chinese Ministry of Science and Technology | Department of S and T for Social Development (Department of S&amp;T for Social Development)/ ; },
abstract = {Several recent studies have shown the presence of genes for the key enzyme associated with archaeal methane/alkane metabolism, methyl-coenzyme M reductase (Mcr), in metagenome-assembled genomes (MAGs) divergent to existing archaeal lineages. Here, we study the mcr-containing archaeal MAGs from several hot springs, which reveal further expansion in the diversity of archaeal organisms performing methane/alkane metabolism. Significantly, an MAG basal to organisms from the phylum Thaumarchaeota that contains mcr genes, but not those for ammonia oxidation or aerobic metabolism, is identified. Together, our phylogenetic analyses and ancestral state reconstructions suggest a mostly vertical evolution of mcrABG genes among methanogens and methanotrophs, along with frequent horizontal gene transfer of mcr genes between alkanotrophs. Analysis of all mcr-containing archaeal MAGs/genomes suggests a hydrothermal origin for these microorganisms based on optimal growth temperature predictions. These results also suggest methane/alkane oxidation or methanogenesis at high temperature likely existed in a common archaeal ancestor.},
}
@article {pmid31587640,
year = {2019},
author = {Santoro, AE and Kellom, M and Laperriere, SM},
title = {Contributions of single-cell genomics to our understanding of planktonic marine archaea.},
journal = {Philosophical transactions of the Royal Society of London. Series B, Biological sciences},
volume = {374},
number = {1786},
pages = {20190096},
doi = {10.1098/rstb.2019.0096},
pmid = {31587640},
issn = {1471-2970},
abstract = {Single-cell genomics has transformed many fields of biology, marine microbiology included. Here, we consider the impact of single-cell genomics on a specific group of marine microbes-the planktonic marine archaea. Despite single-cell enabled discoveries of novel metabolic function in the marine thaumarchaea, population-level investigations are hindered by an overall lower than expected recovery of thaumarchaea in single-cell studies. Metagenome-assembled genomes have so far been a more useful method for accessing genome-resolved insights into the Marine Group II euryarchaea. Future progress in the application of single-cell genomics to archaeal biology in the ocean would benefit from more targeted sorting approaches, and a more systematic investigation of potential biases against archaea in single-cell workflows including cell lysis, genome amplification and genome screening. This article is part of a discussion meeting issue 'Single cell ecology'.},
}
@article {pmid31582767,
year = {2019},
author = {Loth, K and Largillière, J and Coste, F and Culard, F and Landon, C and Castaing, B and Delmas, AF and Paquet, F},
title = {New protein-DNA complexes in archaea: a small monomeric protein induces a sharp V-turn DNA structure.},
journal = {Scientific reports},
volume = {9},
number = {1},
pages = {14253},
doi = {10.1038/s41598-019-50211-2},
pmid = {31582767},
issn = {2045-2322},
abstract = {MC1, a monomeric nucleoid-associated protein (NAP), is structurally unrelated to other DNA-binding proteins. The protein participates in the genome organization of several Euryarchaea species through an atypical compaction mechanism. It is also involved in DNA transcription and cellular division through unknown mechanisms. We determined the 3D solution structure of a new DNA-protein complex formed by MC1 and a strongly distorted 15 base pairs DNA. While the protein just needs to adapt its conformation slightly, the DNA undergoes a dramatic curvature (the first two bend angles of 55° and 70°, respectively) and an impressive torsional stress (dihedral angle of 106°) due to several kinks upon binding of MC1 to its concave side. Thus, it adopts a V-turn structure. For longer DNAs, MC1 stabilizes multiple V-turn conformations in a flexible and dynamic manner. The existence of such V-turn conformations of the MC1-DNA complexes leads us to propose two binding modes of the protein, as a bender (primary binding mode) and as a wrapper (secondary binding mode). Moreover, it opens up new opportunities for studying and understanding the repair, replication and transcription molecular machineries of Archaea.},
}
@article {pmid31568679,
year = {2019},
author = {Ding, J and Ma, M and Jiang, X and Liu, Y and Zhang, J and Suo, L and Wang, L and Wei, D and Li, J},
title = {Effects of applying inorganic fertilizer and organic manure for 35 years on the structure and diversity of ammonia-oxidizing archaea communities in a Chinese Mollisols field.},
journal = {MicrobiologyOpen},
volume = {},
number = {},
pages = {e942},
doi = {10.1002/mbo3.942},
pmid = {31568679},
issn = {2045-8827},
support = {No. ZD2018003//The Natural Science Foundation of Heilongjiang Province/ ; ZZ2019-48//Postdoctoral Research Funds of Beijing/ ; 41771284//National Natural Science Foundation of China/ ; },
abstract = {In this study, we investigated the physicochemical properties of soil, and the diversity and structure of the soil ammonia-oxidizing archaea (AOA) community, when subjected to fertilizer treatments for over 35 years. We collected soil samples from a black soil fertilization trial in northeast China. Four treatments were tested: no fertilization (CK); manure (M); nitrogen (N), phosphorus (P), and potassium (K) chemical fertilizer (NPK); and N, P, and K plus M (MNPK). We employed 454 high-throughput pyrosequencing to measure the response of the soil AOA community to the long-term fertilization. The fertilization treatments had different impacts on the shifts in the soil properties and AOA community. The utilization of manure alleviated soil acidification and enhanced the soybean yield. The soil AOA abundance was increased greatly by inorganic and organic fertilizers. In addition, the community Chao1 and ACE were highest in the MNPK treatment. In terms of the AOA community composition, Thaumarchaeota and Crenarchaeota were the main AOA phyla in all samples. Compared with CK and M, the abundances of Thaumarchaeota were remarkably lower in the MNPK and NPK treatments. There were distinct shifts in the compositions of the AOA operational taxonomic units (OTUs) under different fertilization management practices. OTU51 was the dominant OTU in all treatments, except for NPK. OTU79 and OTU11 were relatively abundant OTUs in NPK. Only Nitrososphaera AOA were tracked from the black soil. Redundancy analysis indicated that the soil pH and soil available P were the two main factors that affected the AOA community structure. The abundances of AOA were positively correlated with the total N and available P concentrations, and negatively correlated with the soil pH.},
}
@article {pmid31552452,
year = {2019},
author = {He, S and Tan, J and Hu, W and Mo, C},
title = {Diversity of Archaea and Its Correlation with Environmental Factors in the Ebinur Lake Wetland.},
journal = {Current microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00284-019-01768-8},
pmid = {31552452},
issn = {1432-0991},
support = {31160026//National Natural Science Foundation of China/ ; },
abstract = {The diversity and community composition of archaea in soil samples from three wetlands (SP1, SP2, and SP3) of Ebinur Lake were studied by constructing 16S rDNA cloning library. The correlation between the diversity of archaea and soil environmental factors was analyzed by CANOCO software. The aim of this study was to reveal the differences of community structures of archaea in different sample sites, to provide a theoretical basis for further study on degradation and restoration of Ebinur Lake wetland. The results showed that Euryarchaeota accounted for 57.1% was the most dominant phylum observed, followed by Thaumarchaeota and Crenarchaeota for the three wetland soil analyzed. Compared with SP3 site, the proportions of Euryarchaeota were decreased by 16.70% and 31.78%, while Thaumarchaeota increased by 7.26% and 17.64% in the SP1 and SP2, respectively. Crenarchaeota was found only in SP3. Shannon-wiener diversity indices in SP1, SP2, and SP3 sites were 3.44, 3.87, and 3.94, respectively, indicating that the diversity of archaea in three plots was: SP3 > SP2 > SP1. Redundancy analysis (RDA) showed that electrical conductivity (EC), soil moisture (SM), hydrogen potential (pH), and soil organic matter content (SOM) may affect archaeal communities. Compared to EC and pH, SM and SOM may have a greater impact on the community composition of archaea.},
}
@article {pmid31533962,
year = {2019},
author = {Mand, TD and Metcalf, WW},
title = {Energy Conservation and Hydrogenase Function in Methanogenic Archaea, in Particular the Genus Methanosarcina.},
journal = {Microbiology and molecular biology reviews : MMBR},
volume = {83},
number = {4},
pages = {},
doi = {10.1128/MMBR.00020-19},
pmid = {31533962},
issn = {1098-5557},
abstract = {SUMMARYThe biological production of methane is vital to the global carbon cycle and accounts for ca. 74% of total methane emissions. The organisms that facilitate this process, methanogenic archaea, belong to a large and phylogenetically diverse group that thrives in a wide range of anaerobic environments. Two main subgroups exist within methanogenic archaea: those with and those without cytochromes. Although a variety of metabolisms exist within this group, the reduction of growth substrates to methane using electrons from molecular hydrogen is, in a phylogenetic sense, the most widespread methanogenic pathway. Methanogens without cytochromes typically generate methane by the reduction of CO2 with electrons derived from H2, formate, or secondary alcohols, generating a transmembrane ion gradient for ATP production via an Na+-translocating methyltransferase (Mtr). These organisms also conserve energy with a novel flavin-based electron bifurcation mechanism, wherein the endergonic reduction of ferredoxin is facilitated by the exergonic reduction of a disulfide terminal electron acceptor coupled to either H2 or formate oxidation. Methanogens that utilize cytochromes have a broader substrate range, and can convert acetate and methylated compounds to methane, in addition to the ability to reduce CO2 Cytochrome-containing methanogens are able to supplement the ion motive force generated by Mtr with an H+-translocating electron transport system. In both groups, enzymes known as hydrogenases, which reversibly interconvert protons and electrons to molecular hydrogen, play a central role in the methanogenic process. This review discusses recent insight into methanogen metabolism and energy conservation mechanisms with a particular focus on the genus Methanosarcina.},
}
@article {pmid31529916,
year = {2016},
author = {Titov, VN and Parchimovitch, RM},
title = {[The phylogenetic theory of general pathology. The becoming of function of at mitochondria at symbiosis of bacterial cells and archaea. Inconsistency of Randle cycle, regulation metabolism of fatty acids and glucose by insulin.].},
journal = {Klinicheskaia laboratornaia diagnostika},
volume = {61},
number = {7},
pages = {388-396},
doi = {10.18821/0860-2084-2016-61-7-388-396},
pmid = {31529916},
issn = {0869-2084},
abstract = {The implementation of Randle rule is not a cycle; fatty acids C4 - ketone bodies at interrelationships with glucose metabolite - pyruvate regulate production of mitochondria of acetyl-KoA by induction of substrate and its conversion in Krebs cycle, reactions of respiratory chain, oxidative phosphorylation and formation of ATP. In phylogenesis, the early substrate for formation of ATP by mitochondria is acetyl-KoA from C4 fatty acids 4; this is alternative A of induction by substrate adopted from archaea. The alternative B of induction in bacteria is based on synthesis of acetyl-KoA by mitohondria from pyruvate developed in cytosol from exogenous glucose. The insulin is late activator of absorption by glucose cells in phylogenesis; using induction by substrate, insulin inhibits absorption of fatty acids by cells and specifically activates absorption of glucose by them. The insulin activates absorption of glucose only by insulin-dependent cells by force of decreasing of &quot;bioavailability&quot; of fatty acids. These cells are preferred to be metabolize by mitochondria from times of archaea. The insulin, blocking lipolysis in insulin-dependent adipocytes &quot;forces&quot; mitochondria, instead of formation of acetyl-KoA from fatty acids, to produce it from pyruvate at activation of glycolysis and pyruvate-dehydrogenased complex. Under effect of insulin, mitochondria form acetyl-KoA and synthesize ATP from oleic mono-saturated fatty acids but not from palmitic saturated fatty acids. The kinetic parameters of second reaction and formation of ATP per unit of time (effectiveness) are much higher than in first reaction. The effectiveness of i9mplementation of alternative A in synthesis of ATP, kinetic parameters of production of acetyl-KoA in mitochondria in alternative A are more effective than in case of alternative B and metabolic conversion of glucose. The syndrome of resistance to insulin is, at the first place, pathology of metabolism of fatty acids and only in the second place metabolism of glucose. The incapacity of insulin to block lipolysis in the phylogenetically earlier visceral fatty cells is the basis of resistance.},
}
@article {pmid31522353,
year = {2019},
author = {Sereme, Y and Mezouar, S and Grine, G and Mege, JL and Drancourt, M and Corbeau, P and Vitte, J},
title = {Methanogenic Archaea: Emerging Partners in the Field of Allergic Diseases.},
journal = {Clinical reviews in allergy &amp; immunology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s12016-019-08766-5},
pmid = {31522353},
issn = {1559-0267},
support = {10-IAHU-03//Agence Nationale de la Recherche/ ; PhD//Fondation Méditerranée Infection/ ; post-doctoral//Fondation Méditerranée Infection/ ; PhD//Fondation Méditerranée Infection/ ; },
abstract = {Archaea, which form one of four domains of life alongside Eukarya, Bacteria, and giant viruses, have long been neglected as components of the human microbiota and potential opportunistic infectious pathogens. In this review, we focus on methanogenic Archaea, which rely on hydrogen for their metabolism and growth. On one hand, methanogenic Archaea in the gut are functional associates of the fermentative digestion of dietary fibers, favoring the production of beneficial short-chain fatty acids and likely contributing to the weaning reaction during the neonatal window of opportunity. On the other hand, methanogenic Archaea trigger the activation of innate and adaptive responses and the generation of specific T and B cells in animals and humans. In mouse models, lung hypersensitivity reactions can be induced by inhaled methanogenic Archaea mimicking human professional exposure to organic dust. Changes in methanogenic Archaea of the microbiota are detected in an array of dysimmune conditions comprising inflammatory bowel disease, obesity, malnutrition, anorexia, colorectal cancer, and diverticulosis. At the subcellular level, methanogenic Archaea are activators of the TLR8-dependent NLRP3 inflammasome, modulate the release of antimicrobial peptides and drive the production of proinflammatory, Th-1, Th-2, and Th-17 cytokines. Our objective was to introduce the most recent and major pieces of evidence supporting the involvement of Archaea in the balance between health and dysimmune diseases, with a particular focus on atopic and allergic conditions.},
}
@article {pmid31520950,
year = {2019},
author = {Pal, S and Sar, A and Dam, B},
title = {Moderate halophilic bacteria, but not extreme halophilic archaea can alleviate the toxicity of short-alkyl side chain imidazolium-based ionic liquids.},
journal = {Ecotoxicology and environmental safety},
volume = {184},
number = {},
pages = {109634},
doi = {10.1016/j.ecoenv.2019.109634},
pmid = {31520950},
issn = {1090-2414},
abstract = {Imidazolium-based ionic liquids (IL) with short-alkyl side chain such as 1-ethyl-3-methyl-imidazolium chloride ([Emim]Cl) and 1-butyl-3-methyl-imidazolium chloride ([Bmim]Cl) has immense application potential including in lignocellulosic bioenergy production. But they are toxic to most microorganisms, and those isolated from different environments as IL-tolerant have salt tolerance capabilities. This study evaluates the relationship between salt and [Emim]Cl tolerance of microorganisms using different salinity sediments (2-19%) and brines (35%) of India's largest inland hypersaline lake, Sambhar in Rajasthan as the model system. While samples with 2% and 35% salinities do not yield any [Emim]Cl (100 mM) tolerant colonies, others have 6-50% colonies tolerant to the IL. Similar trend was observed with 50 mM [Bmim]Cl. Moderate halophilic isolates of genera Halomonas and Bacillus (growth in 0.7-3.0 M NaCl) isolated from the sediments could grow in as high as 375 mM [Emim]Cl, or 125 mM [Bmim]Cl facilitated by higher synthesis, and uptake of organic osmolytes; and up to 1.7-fold increased activity of active efflux pumps. [Bmim]Cl was more toxic than [Emim]Cl in all performed experiments. [Emim]Cl-adapted cells could trounce IL-induced stress. Interestingly, enrichment with 100 mM [Emim]Cl resulted in increase of IL-tolerant colonies in all sediments including the one with 2% salinity. However, the salt saturated brines (35%) do not yield any such colony even after repeated incubations. Extreme halophilic archaea, Natronomonas (growth in 3.0-4.0 M NaCl) isolated from such brines, were exceedingly sensitive to even 5 mM [Emim]Cl, or 1 mM [Bmim]Cl. Two additional extremophilic archaea, namely Haloferax and Haladaptatus were also sensitive to the tested ILs. Archaeal sensitivity is possibly due to the competitive interaction of [Emim]+ with their acidic proteome (15.4-17.5% aspartic and glutamic acids, against 10.7-12.9% in bacteria) that they maintain to stabilize the high amount of K+ ion accumulated by salt-in strategy. Thus, general salt adaptation strategies of moderate halophilic bacteria help them to restrain toxicity of these ILs, but extremophilic archaea are highly sensitive and demands meticulous use of these solvents to prevent environmental contamination.},
}
@article {pmid31505830,
year = {2019},
author = {Salvador-Castell, M and Tourte, M and Oger, PM},
title = {In Search for the Membrane Regulators of Archaea.},
journal = {International journal of molecular sciences},
volume = {20},
number = {18},
pages = {},
doi = {10.3390/ijms20184434},
pmid = {31505830},
issn = {1422-0067},
support = {ANR 17-CE11-0012-01//Agence Nationale de la Recherche/ ; Origines &quot;ReseArch&quot;//Centre National de la Recherche Scientifique/ ; },
abstract = {Membrane regulators such as sterols and hopanoids play a major role in the physiological and physicochemical adaptation of the different plasmic membranes in Eukarya and Bacteria. They are key to the functionalization and the spatialization of the membrane, and therefore indispensable for the cell cycle. No archaeon has been found to be able to synthesize sterols or hopanoids to date. They also lack homologs of the genes responsible for the synthesis of these membrane regulators. Due to their divergent membrane lipid composition, the question whether archaea require membrane regulators, and if so, what is their nature, remains open. In this review, we review evidence for the existence of membrane regulators in Archaea, and propose tentative location and biological functions. It is likely that no membrane regulator is shared by all archaea, but that they may use different polyterpenes, such as carotenoids, polyprenols, quinones and apolar polyisoprenoids, in response to specific stressors or physiological needs.},
}
@article {pmid31504156,
year = {2019},
author = {Bønløkke, JH and Duchaine, C and Schlünssen, V and Sigsgaard, T and Veillette, M and Basinas, I},
title = {Archaea and Bacteria Exposure in Danish Livestock Farmers.},
journal = {Annals of work exposures and health},
volume = {},
number = {},
pages = {},
doi = {10.1093/annweh/wxz058},
pmid = {31504156},
issn = {2398-7316},
abstract = {OBJECTIVES: Methanogenic archaea have been found to make up part of the bioaerosols in pig, cattle, and poultry farms. So far no attempts have been made to determine how season, farm type, and farm characteristics may affect workers' exposure to archaea.<br><br>METHODS: Personal filter samples from 327 farmers working on 89 Danish farms were analysed for the number of 16S rRNA gene copies from archaea and bacteria and for their dust and endotoxin content. The farms were visited during summer and winter. Information on farm type and stable characteristics were collected using self-reported activity diaries and walk-through surveys. Differences in archaea and bacteria levels with farm type and stable characteristics and correlations with dust and endotoxin levels were examined.<br><br>RESULTS: Personal archaea exposure was documented in all farm types including, for the first time, during mink farming. At 7.3*104 gene copies m-3 the archaea levels were around two orders of magnitude lower than bacteria levels at 5.7*106 gene copies m-3. At 1.7*105 gene copies m-3 among pig farmers and 1.9*104 gene copies m-3 among cattle farmers the archaea levels differed with farm type (P < 0.0005). The archaea and bacteria levels correlated weakly with a Pearson correlation coefficient of 0.17. Neither archaea nor bacteria levels differed by season. In pig farms the archaea levels differed by type of ventilation and by wetness of the floor.<br><br>CONCLUSIONS: Archaea levels were not neglible and appeared to vary greatly between farm types. In pig farms they varied with some farm characteristics. Archaea levels appeared to depend on factors that differed from those of bacteria.},
}
@article {pmid31488843,
year = {2019},
author = {Huber, M and Faure, G and Laass, S and Kolbe, E and Seitz, K and Wehrheim, C and Wolf, YI and Koonin, EV and Soppa, J},
title = {Translational coupling via termination-reinitiation in archaea and bacteria.},
journal = {Nature communications},
volume = {10},
number = {1},
pages = {4006},
doi = {10.1038/s41467-019-11999-9},
pmid = {31488843},
issn = {2041-1723},
abstract = {The genomes of many prokaryotes contain substantial fractions of gene pairs with overlapping stop and start codons (ATGA or TGATG). A potential benefit of overlapping gene pairs is translational coupling. In 720 genomes of archaea and bacteria representing all major phyla, we identify substantial, albeit highly variable, fractions of co-directed overlapping gene pairs. Various patterns are observed for the utilization of the SD motif for de novo initiation at upstream genes versus reinitiation at overlapping gene pairs. We experimentally test the predicted coupling in 9 gene pairs from the archaeon Haloferax volcanii and 5 gene pairs from the bacterium Escherichia coli. In 13 of 14 cases, translation of both genes is strictly coupled. Mutational analysis of SD motifs located upstream of the downstream genes indicate that the contribution of the SD to translational coupling widely varies from gene to gene. The nearly universal, abundant occurrence of overlapping gene pairs suggests that tight translational coupling is widespread in archaea and bacteria.},
}
@article {pmid31437442,
year = {2019},
author = {Hackley, RK and Schmid, AK},
title = {Global transcriptional programs in archaea share features with the eukaryotic environmental stress response.},
journal = {Journal of molecular biology},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.jmb.2019.07.029},
pmid = {31437442},
issn = {1089-8638},
abstract = {The environmental stress response (ESR), a global transcriptional program originally identified in yeast, is characterized by a rapid and transient transcriptional response composed of large, oppositely regulated gene clusters. Genes induced during the ESR encode core components of stress tolerance, macromolecular repair, and maintenance of homeostasis. In this review, we investigate the possibility for conservation of the ESR across the eukaryotic and archaeal domains of life. We first re-analyze existing transcriptomics datasets to illustrate that a similar transcriptional response is identifiable in Halobacterium salinarum, an archaeal model organism. To substantiate the archaeal ESR, gene-by-gene correlations, gene function enrichment, and comparison of temporal dynamics are used. We note reported examples of variation in the ESR across fungi, then synthesize high-level trends present in expression data of other archaeal species. In particular, we emphasize the need for additional high-throughput time series expression data to further characterize stress-responsive transcriptional programs in the Archaea. Together, this review explores an exciting open question regarding features of global transcriptional stress response programs shared across domains of life.},
}
@article {pmid31435153,
year = {2019},
author = {Bandyopadhyay, AK and Islam, RNU and Mitra, D and Banerjee, S and Goswami, A},
title = {Structural insights from water-ferredoxin interaction in mesophilic algae and halophilic archaea.},
journal = {Bioinformation},
volume = {15},
number = {2},
pages = {79-89},
doi = {10.6026/97320630015079},
pmid = {31435153},
issn = {0973-2063},
abstract = {We analyzed the water-ferredoxin interaction in mesophilic (moderate temperature) algae (PDB ID: 1AWD) and halophilic (salt-tolerant) archaea (PDB ID: 1DOI) using POWAIND version 2.0 (a protein-water interactions calculation program). It is found that the shell water (SW) is 2.5 fold greater in halophilic ferredoxin than mesophilic ferredoxin. Water-ferredoxin interactions in the core and cavity are the signature of stability. The normalized frequency of such interactions is less in halophilic relative to mesophilic ferredoxin and the halophilic signature for stability by such interactions is negligible. However, the surface dominated with such interactions seems to be important for ferredoxin and oxido-reductase recognition.},
}
@article {pmid31432245,
year = {2019},
author = {Sun, Y and Liu, Y and Pan, J and Wang, F and Li, M},
title = {Perspectives on Cultivation Strategies of Archaea.},
journal = {Microbial ecology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00248-019-01422-7},
pmid = {31432245},
issn = {1432-184X},
support = {31622002//NSFC/ ; 91851105//NSFC/ ; },
abstract = {Archaea have been recognized as a major domain of life since the 1970s and occupy a key position in the tree of life. Recent advances in culture-independent approaches have greatly accelerated the research son Archaea. However, many hypotheses concerning the diversity, physiology, and evolution of archaea are waiting to be confirmed by culture-base experiments. Consequently, archaeal isolates are in great demand. On the other hand, traditional approaches of archaeal cultivation are rarely successful and require urgent improvement. Here, we review the current practices and applicable microbial cultivation techniques, to inform on potential strategies that could improve archaeal cultivation in the future. We first summarize the current knowledge on archaeal diversity, with an emphasis on cultivated and uncultivated lineages pertinent to future research. Possible causes for the low success rate of the current cultivation practices are then discussed to propose future improvements. Finally, innovative insights for archaeal cultivation are described, including (1) medium refinement for selective cultivation based on the genetic and transcriptional information; (2) consideration of the up-to-date archaeal culturing skills; and (3) application of multiple cultivation techniques, such as co-culture, direct interspecies electron transfer (DIET), single-cell isolation, high-throughput culturing (HTC), and simulation of the natural habitat. Improved cultivation efforts should allow successful isolation of as yet uncultured archaea, contributing to the much-needed physiological investigation of archaea.},
}
@article {pmid31416876,
year = {2019},
author = {DasSarma, P and Anton, BP and DasSarma, SL and Martinez, FL and Guzman, D and Roberts, RJ and DasSarma, S},
title = {Genome Sequences and Methylation Patterns of Natrinema versiforme BOL5-4 and Natrinema pallidum BOL6-1, Two Extremely Halophilic Archaea from a Bolivian Salt Mine.},
journal = {Microbiology resource announcements},
volume = {8},
number = {33},
pages = {},
doi = {10.1128/MRA.00810-19},
pmid = {31416876},
issn = {2576-098X},
abstract = {Two extremely halophilic archaea, namely, Natrinema versiforme BOL5-4 and Natrinema pallidum BOL6-1, were isolated from a Bolivian salt mine and their genomes sequenced using single-molecule real-time sequencing. The GC-rich genomes of BOL5-4 and BOL6-1 were 4.6 and 3.8 Mbp, respectively, with large chromosomes and multiple megaplasmids. Genome annotation was incorporated into HaloWeb and methylation patterns incorporated into REBASE.},
}
@article {pmid31411686,
year = {2019},
author = {Tang, Z and Chen, S and Chen, A and He, B and Zhou, Y and Chai, G and Guo, F and Huang, J},
title = {CasPDB: an integrated and annotated database for Cas proteins from bacteria and archaea.},
journal = {Database : the journal of biological databases and curation},
volume = {2019},
number = {},
pages = {},
doi = {10.1093/database/baz093},
pmid = {31411686},
issn = {1758-0463},
abstract = {Clustered regularly interspaced short palindromic repeats (CRISPR) and associated proteins (Cas) constitute CRISPR-Cas systems, which are antiphage immune systems present in numerous bacterial and most archaeal species. In recent years, CRISPR-Cas systems have been developed into reliable and powerful genome editing tools. Nevertheless, finding similar or better tools from bacteria or archaea remains crucial. This requires the exploration of different CRISPR systems, identification and characterization new Cas proteins. Archives tailored for Cas proteins are urgently needed and necessitate the prediction and grouping of Cas proteins into an information center with all available experimental evidence. Here, we constructed Cas Protein Data Bank (CasPDB), an integrated and annotated online database for Cas proteins from bacteria and archaea. The CasPDB database contains 287 reviewed Cas proteins, 257 745 putative Cas proteins and 3593 Cas operons from 32 023 bacteria species and 1802 archaea species. The database can be freely browsed and searched. The CasPDB web interface also represents all the 3593 putative Cas operons and its components. Among these operons, 328 are members of the type II CRISPR-Cas system.},
}
@article {pmid31407306,
year = {2019},
author = {Yin, X and Kulkarni, AC and Friedrich, MW},
title = {DNA and RNA Stable Isotope Probing of Methylotrophic Methanogenic Archaea.},
journal = {Methods in molecular biology (Clifton, N.J.)},
volume = {2046},
number = {},
pages = {189-206},
doi = {10.1007/978-1-4939-9721-3_15},
pmid = {31407306},
issn = {1940-6029},
abstract = {Methylotrophic methanogenic archaea are an integral part of the carbon cycle in various anaerobic environments. Different from methylotrophic bacteria, methylotrophic methanogens assimilate both, the methyl compound and dissolved inorganic carbon. Here, we present DNA- and RNA-stable isotope probing (SIP) methods involving an effective labeling strategy using 13C-labeled dissolved inorganic carbon (DIC) as carbon source along with methanol as dissimilatory substrate.},
}
@article {pmid31397430,
year = {2019},
author = {Khlebodarova, TM and Likhoshvai, VA},
title = {[Molecular Mechanisms of Non-Inherited Antibiotic Tolerance in Bacteria and Archaea].},
journal = {Molekuliarnaia biologiia},
volume = {53},
number = {4},
pages = {531-540},
doi = {10.1134/S0026898419040050},
pmid = {31397430},
issn = {0026-8984},
abstract = {The phenomenon of bacterial persistence, also known as non-inherited antibiotic tolerance in a part of bacterial populations, was described more than 70 years ago. This type of tolerance contributes to the chronization of infectious diseases, including tuberculosis. Currently, the emergence of persistent cells in bacterial populations is associated with the functioning of some stress-induced molecular triggers, including toxin-antitoxin systems. In the presented review, genetic and metabolic peculiarities of persistent cells are considered and the mechanisms of their occurrence are discussed. The hypothesis of the origin of persister cells based on bistability, arising due to the non-linear properties of a coupled transcription-translation system, was proposed. Within this hypothesis, the phenomenon of the bacterial persistence of modern cells is considered as a result of the genetic fixation of the phenotypic multiplicity that emerged in primitive cells in the process of neutrally coupled co-evolution (genetic drift of multiple neutrally coupled mutations). Our hypothesis explains the properties of persister cells, as well as their origin and &quot;ineradicable&quot; nature.},
}
@article {pmid31388130,
year = {2019},
author = {Steen, AD and Crits-Christoph, A and Carini, P and DeAngelis, KM and Fierer, N and Lloyd, KG and Cameron Thrash, J},
title = {High proportions of bacteria and archaea across most biomes remain uncultured.},
journal = {The ISME journal},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41396-019-0484-y},
pmid = {31388130},
issn = {1751-7370},
support = {OCE-1431598//National Science Foundation (NSF)/ ; 404586//Simons Foundation/ ; },
abstract = {A recent paper by Martiny argues that &quot;high proportions&quot; of bacteria in diverse Earth environments have been cultured. Here we reanalyze a portion of the data in that paper, and argue that the conclusion is based on several technical errors, most notably a calculation of sequence similarity that does not account for sequence gaps, and the reliance on 16S rRNA gene amplicons that are known to be biased towards cultured organisms. We further argue that the paper is also based on a conceptual error: namely, that sequence similarity cannot be used to infer &quot;culturability&quot; because one cannot infer physiology from 16S rRNA gene sequences. Combined with other recent, more reliable studies, the evidence supports the conclusion that most bacterial and archaeal taxa remain uncultured.},
}
@article {pmid31384725,
year = {2019},
author = {Blum, P and Payne, S},
title = {Evidence of an Epigenetics System in Archaea.},
journal = {Epigenetics insights},
volume = {12},
number = {},
pages = {2516865719865280},
doi = {10.1177/2516865719865280},
pmid = {31384725},
issn = {2516-8657},
abstract = {Changes in the phenotype of a cell or organism that are heritable but do not involve changes in DNA sequence are referred to as epigenetic. They occur primarily through the gain or loss of chemical modification of chromatin protein or DNA. Epigenetics is therefore a non-Mendelian process. The study of epigenetics in eukaryotes is expanding with advances in knowledge about the relationship between mechanism and phenotype and as a requirement for multicellularity and cancer. However, life also includes other groups or domains, notably the bacteria and archaea. The occurrence of epigenetics in these deep lineages is an emerging topic accompanied by controversy. In these non-eukaryotic organisms, epigenetics is critically important because it stimulates new evolutionary theory and refines perspective about biological action.},
}
@article {pmid31384702,
year = {2019},
author = {MacLeod, F and Kindler, GS and Wong, HL and Chen, R and Burns, BP},
title = {Asgard archaea: Diversity, function, and evolutionary implications in a range of microbiomes.},
journal = {AIMS microbiology},
volume = {5},
number = {1},
pages = {48-61},
doi = {10.3934/microbiol.2019.1.48},
pmid = {31384702},
issn = {2471-1888},
abstract = {Elucidating the diversity of the Archaea has many important ecological and evolutionary implications. The Asgard superphylum of the archaea, described recently from metagenomic data, has reignited the decades-old debate surrounding the topology of the tree of life. This review synthesizes recent findings through publicly available genomes and literature to describe the current ecological and evolutionary significance of the Asgard superphylum. Asgard archaea have been found in a diverse range of microbiomes across the globe, primarily from sedimentary environments. Within these environments, positive correlations between specific members of the Asgard archaea and Candidate Division TA06 bacteria have been observed, opening up the possibility of symbiotic interactions between the groupings. Asgard archaeal genomes encode functionally diverse metabolic pathways, including the Wood-Ljungdahl pathway as a carbon-fixation strategy, putative nucleotide salvaging pathways, and novel mechanisms of phototrophy including new rhodopsins. Asgard archaea also appear to be active in nitrogen cycling. Asgard archaea encode genes involved in both dissimilatory nitrate reduction and denitrification, and for the potential to use atmospheric nitrogen or nitrite as nitrogen sources. Asgard archaea also may be involved in the transformation of sulfur compounds, indicating a putative role in sulfur cycling. To date, all Asgard archaeal genomes identified were described as obligately anaerobic. The Asgard archaea also appear to have important evolutionary implications. The presence of eukaryotic signature proteins and the affiliation of Asgard archaea in phylogenetic analyses appears to support two-domain topologies of the tree of life with eukaryotes emerging from within the domain of archaea, as opposed to the eukaryotes being a separate domain of life. Thus far, Heimdallarchaeota appears as the closest archaeal relative of eukaryotes.},
}
@article {pmid31377507,
year = {2019},
author = {Pan, KL and Gao, JF and Li, DC and Fan, XY},
title = {The dominance of non-halophilic archaea in autotrophic ammonia oxidation of activated sludge under salt stress: A DNA-based stable isotope probing study.},
journal = {Bioresource technology},
volume = {291},
number = {},
pages = {121914},
doi = {10.1016/j.biortech.2019.121914},
pmid = {31377507},
issn = {1873-2976},
abstract = {Dynamics of nitrification activity, ammonia-oxidizing archaea (AOA) and bacteria (AOB) abundance and active ammonia oxidizers of activated sludge were explored under different salinities. Results showed that specific ammonium oxidation rates were significantly negative with increasing salinity. The responses of AOA and AOB populations to salt stress were distinct. AOA abundance decreased at moderate salinities (2.5, 5 and 7 g L-1) and increased at high salinities (10, 15, 20 and 30 g L-1), while AOB abundance showed opposite tendency. DNA-based stable isotope probing assays indicated AOA exclusively dominated active ammonia oxidation of test samples under different salinities. The active AOA communities retrieved were all non-halophilic and regulated by salinities. Candidatus Nitrosocosmicus exaquare and Ca. Nitrosocosmicus franklandus were the predominantly active AOA in both salt-free and salt-containing microcosms, while 13C-labeled Nitrososphaera viennensis and Ca. Nitrososphaera gargensis were only retrieved from the microcosms amended with 0 and 30 g L-1 salinity, respectively.},
}
@article {pmid31364272,
year = {2019},
author = {Bird, LR and Dawson, KS and Chadwick, GL and Fulton, JM and Orphan, VJ and Freeman, KH},
title = {Carbon isotopic heterogeneity of coenzyme F430 and membrane lipids in methane-oxidizing archaea.},
journal = {Geobiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/gbi.12354},
pmid = {31364272},
issn = {1472-4669},
support = {//ConocoPhillips graduate student fellowship/ ; GBMF 3306//Gordon and Betty Moore Foundation/ ; //Royal Dutch Shell Geosciences Energy Research Facilitation Awards/ ; //Penn State 592 Astrobiology Research Center and Pennsylvania Space Grant/ ; 54478-ND2//American Chemical Society Petroleum Research Fund/ ; },
abstract = {Archaeal ANaerobic MEthanotrophs (ANME) facilitate the anaerobic oxidation of methane (AOM), a process that is believed to proceed via the reversal of the methanogenesis pathway. Carbon isotopic composition studies indicate that ANME are metabolically diverse and able to assimilate metabolites including methane, methanol, acetate, and dissolved inorganic carbon (DIC). Our data support the interpretation that ANME in marine sediments at methane seeps assimilate both methane and DIC, and the carbon isotopic compositions of the tetrapyrrole coenzyme F430 and the membrane lipids archaeol and hydroxy-archaeol reflect their relative proportions of carbon from these substrates. Methane is assimilated via the methyl group of CH3 -tetrahydromethanopterin (H4 MPT) and DIC from carboxylation reactions that incorporate free intracellular DIC. F430 was enriched in 13 C (mean δ13 C = -27‰ for Hydrate Ridge and -80‰ for the Santa Monica Basin) compared to the archaeal lipids (mean δ13 C = -97‰ for Hydrate Ridge and -122‰ for the Santa Monica Basin). We propose that depending on the side of the tricarboxylic acid (TCA) cycle used to synthesize F430, its carbon was derived from 76% DIC and 24% methane via the reductive side or 57% DIC and 43% methane via the oxidative side. ANME lipids are predicted to contain 42% DIC and 58% methane, reflecting the amount of each assimilated into acetyl-CoA. With isotope models that include variable fractionation during biosynthesis for different carbon substrates, we show the estimated amounts of DIC and methane can result in carbon isotopic compositions of - 73‰ to - 77‰ for F430 and - 105‰ for archaeal lipids, values close to those for Santa Monica Basin. The F430 δ13 C value for Hydrate Ridge was 13 C-enriched compared with the modeled value, suggesting there is divergence from the predicted two carbon source models.},
}
@article {pmid31363851,
year = {2019},
author = {Beyer, HM and Mikula, KM and Kudling, TV and Iwaï, H},
title = {Crystal structures of CDC21-1 inteins from hyperthermophilic archaea reveal the selection mechanism for the highly conserved homing endonuclease insertion site.},
journal = {Extremophiles : life under extreme conditions},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00792-019-01117-4},
pmid = {31363851},
issn = {1433-4909},
support = {131413//Biotieteiden ja Ympäristön Tutkimuksen Toimikunta/ ; 137995//Biotieteiden ja Ympäristön Tutkimuksen Toimikunta/ ; 277335//Biotieteiden ja Ympäristön Tutkimuksen Toimikunta/ ; NNF17OC0025402//Novo Nordisk Foundation/ ; NNF17OC0027550//Novo Nordisk Foundation/ ; },
abstract = {Self-splicing inteins are mobile genetic elements invading host genes via nested homing endonuclease (HEN) domains. All HEN domains residing within inteins are inserted at a highly conserved insertion site. A purifying selection mechanism directing the location of the HEN insertion site has not yet been identified. In this work, we solved the three-dimensional crystal structures of two inteins inserted in the cell division control protein 21 of the hyperthermophilic archaea Pyrococcus abyssi and Pyrococcus horikoshii. A comparison between the structures provides the structural basis for the thermo-stabilization mechanism of inteins that have lost the HEN domain during evolution. The presence of an entire extein domain in the intein structure from Pyrococcus horikoshii suggests the selection mechanism for the highly conserved HEN insertion point.},
}
@article {pmid31341668,
year = {2019},
author = {Taffner, J and Cernava, T and Erlacher, A and Berg, G},
title = {Novel insights into plant-associated archaea and their functioning in arugula (Eruca sativa Mill.).},
journal = {Journal of advanced research},
volume = {19},
number = {},
pages = {39-48},
doi = {10.1016/j.jare.2019.04.008},
pmid = {31341668},
issn = {2090-1232},
abstract = {A plant's microbiota has various implications for the plant's health and performance; however, the roles of many microbial lineages, particularly Archaea, have not been explored in detail. In the present study, analysis of archaea-specific 16S rRNA gene fragments and shotgun-sequenced metagenomes was combined with visualization techniques to obtain the first insights into the archaeome of a common salad plant, arugula (Eruca sativa Mill.). The archaeal communities associated with the soil, rhizosphere and phyllosphere were distinct, but a high proportion of community members were shared among all analysed habitats. Soil habitats exhibited the highest diversity of Archaea, followed by the rhizosphere and the phyllosphere. The archaeal community was dominated by Thaumarchaeota and Euryarchaeota, with the most abundant taxa assigned to Candidatus Nitrosocosmicus, species of the 'Soil Crenarchaeotic Group' and, interestingly, Methanosarcina. Moreover, a large number of archaea-assigned sequences remained unassigned at lower taxonomic levels. Overall, analysis of shotgun-sequenced total-community DNA revealed a more diverse archaeome. Differences were evident at the class level and at higher taxonomic resolutions when compared to results from the 16S rRNA gene fragment amplicon library. Functional assessments primarily revealed archaeal genes related to response to stress (especially oxidative stress), CO2 fixation, and glycogen degradation. Microscopic visualizations of fluorescently labelled archaea in the phyllosphere revealed small scattered colonies, while archaea in the rhizosphere were found to be embedded within large bacterial biofilms. Altogether, Archaea were identified as a rather small but niche-specific component of the microbiomes of the widespread leafy green plant arugula.},
}
@article {pmid31337720,
year = {2019},
author = {Shimosaka, T and Makarova, KS and Koonin, EV and Atomi, H},
title = {Identification of Dephospho-Coenzyme A (Dephospho-CoA) Kinase in Thermococcus kodakarensis and Elucidation of the Entire CoA Biosynthesis Pathway in Archaea.},
journal = {mBio},
volume = {10},
number = {4},
pages = {},
doi = {10.1128/mBio.01146-19},
pmid = {31337720},
issn = {2150-7511},
abstract = {Dephospho-coenzyme A (dephospho-CoA) kinase (DPCK) catalyzes the ATP-dependent phosphorylation of dephospho-CoA, the final step in coenzyme A (CoA) biosynthesis. DPCK has been identified and characterized in bacteria and eukaryotes but not in archaea. The hyperthermophilic archaeon Thermococcus kodakarensis encodes two homologs of bacterial DPCK and the DPCK domain of eukaryotic CoA synthase, TK1334 and TK2192. We purified the recombinant TK1334 and TK2192 proteins and found that they lacked DPCK activity. Bioinformatic analyses showed that, in several archaea, the uncharacterized gene from arCOG04076 protein is fused with the gene for phosphopantetheine adenylyltransferase (PPAT), which catalyzes the reaction upstream of the DPCK reaction in CoA biosynthesis. This observation suggested that members of arCOG04076, both fused to PPAT and standalone, could be the missing archaeal DPCKs. We purified the recombinant TK1697 protein, a standalone member of arCOG04076 from T. kodakarensis, and demonstrated its GTP-dependent DPCK activity. Disruption of the TK1697 resulted in CoA auxotrophy, indicating that TK1697 encodes a DPCK that contributes to CoA biosynthesis in T. kodakarensis TK1697 homologs are widely distributed in archaea, suggesting that the arCOG04076 protein represents a novel family of DPCK that is not homologous to bacterial and eukaryotic DPCKs but is distantly related to bacterial and eukaryotic thiamine pyrophosphokinases. We also constructed and characterized gene disruption strains of TK0517 and TK2128, homologs of bifunctional phosphopantothenoylcysteine synthetase-phosphopantothenoylcysteine decarboxylase and PPAT, respectively. Both strains displayed CoA auxotrophy, indicating their contribution to CoA biosynthesis. Taken together with previous studies, the results experimentally validate the entire CoA biosynthesis pathway in T. kodakarensisIMPORTANCE CoA is utilized in a wide range of metabolic pathways, and its biosynthesis is essential for all life. Pathways for CoA biosynthesis in bacteria and eukaryotes have been established. In archaea, however, the enzyme that catalyzes the final step in CoA biosynthesis, dephospho-CoA kinase (DPCK), had not been identified. In the present study, bioinformatic analyses identified a candidate for the DPCK in archaea, which was biochemically and genetically confirmed in the hyperthermophilic archaeon Thermococcus kodakarensis Genetic analyses on genes presumed to encode bifunctional phosphopantothenoylcysteine synthetase-phosphopantothenoylcysteine decarboxylase and phosphopantetheine adenylyltransferase confirmed their involvement in CoA biosynthesis. Taken together with previous studies, the results reveal the entire pathway for CoA biosynthesis in a single archaeon and provide insight into the different mechanisms of CoA biosynthesis and their distribution in nature.},
}
@article {pmid31336026,
year = {2019},
author = {Bayer, B and Hansman, RL and Bittner, MJ and Noriega-Ortega, BE and Niggemann, J and Dittmar, T and Herndl, GJ},
title = {Ammonia-oxidizing archaea release a suite of organic compounds potentially fueling prokaryotic heterotrophy in the ocean.},
journal = {Environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/1462-2920.14755},
pmid = {31336026},
issn = {1462-2920},
support = {P28781-B21//Austrian Science Fund/ ; W1257-B20//Austrian Science Fund/ ; },
abstract = {Ammonia-oxidizing archaea (AOA) constitute a considerable fraction of microbial biomass in the global ocean, comprising 20%-40% of the ocean's prokaryotic plankton. However, it remains enigmatic to what extent these chemolithoautotrophic archaea release dissolved organic carbon (DOC). A combination of targeted and untargeted metabolomics was used to characterize the exometabolomes of three model AOA strains of the Nitrosopumilus genus. Our results indicate that marine AOA exude a suite of organic compounds with potentially varying reactivities, dominated by nitrogen-containing compounds. A significant fraction of the released dissolved organic matter (DOM) consists of labile compounds, which typically limit prokaryotic heterotrophic activity in open ocean waters, including amino acids, thymidine and B vitamins. Amino acid release rates corresponded with ammonia oxidation activity and the three Nitrosopumilus strains predominantly released hydrophobic amino acids, potentially as a result of passive diffusion. Despite the low contribution of DOC released by AOA (~0.08%-1.05%) to the heterotrophic prokaryotic carbon demand, the release of physiologically relevant metabolites could be crucial for microbes that are auxotrophic for some of these compounds, including members of the globally abundant and ubiquitous SAR11 clade.},
}
@article {pmid31332386,
year = {2019},
author = {Roux, S and Krupovic, M and Daly, RA and Borges, AL and Nayfach, S and Schulz, F and Sharrar, A and Matheus Carnevali, PB and Cheng, JF and Ivanova, NN and Bondy-Denomy, J and Wrighton, KC and Woyke, T and Visel, A and Kyrpides, NC and Eloe-Fadrosh, EA},
title = {Cryptic inoviruses revealed as pervasive in bacteria and archaea across Earth's biomes.},
journal = {Nature microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41564-019-0510-x},
pmid = {31332386},
issn = {2058-5276},
abstract = {Bacteriophages from the Inoviridae family (inoviruses) are characterized by their unique morphology, genome content and infection cycle. One of the most striking features of inoviruses is their ability to establish a chronic infection whereby the viral genome resides within the cell in either an exclusively episomal state or integrated into the host chromosome and virions are continuously released without killing the host. To date, a relatively small number of inovirus isolates have been extensively studied, either for biotechnological applications, such as phage display, or because of their effect on the toxicity of known bacterial pathogens including Vibrio cholerae and Neisseria meningitidis. Here, we show that the current 56 members of the Inoviridae family represent a minute fraction of a highly diverse group of inoviruses. Using a machine learning approach leveraging a combination of marker gene and genome features, we identified 10,295 inovirus-like sequences from microbial genomes and metagenomes. Collectively, our results call for reclassification of the current Inoviridae family into a viral order including six distinct proposed families associated with nearly all bacterial phyla across virtually every ecosystem. Putative inoviruses were also detected in several archaeal genomes, suggesting that, collectively, members of this supergroup infect hosts across the domains Bacteria and Archaea. Finally, we identified an expansive diversity of inovirus-encoded toxin-antitoxin and gene expression modulation systems, alongside evidence of both synergistic (CRISPR evasion) and antagonistic (superinfection exclusion) interactions with co-infecting viruses, which we experimentally validated in a Pseudomonas model. Capturing this previously obscured component of the global virosphere may spark new avenues for microbial manipulation approaches and innovative biotechnological applications.},
}
@article {pmid31320751,
year = {2019},
author = {Eloe-Fadrosh, EA},
title = {Genome gazing in ammonia-oxidizing archaea.},
journal = {Nature reviews. Microbiology},
volume = {17},
number = {9},
pages = {531},
doi = {10.1038/s41579-019-0248-8},
pmid = {31320751},
issn = {1740-1534},
}
@article {pmid31314099,
year = {2019},
author = {Liu, TT and Yang, H},
title = {An RNA-based quantitative and compositional study of ammonium-oxidizing bacteria and archaea in Lake Taihu, a eutrophic freshwater lake.},
journal = {FEMS microbiology ecology},
volume = {95},
number = {9},
pages = {},
doi = {10.1093/femsec/fiz117},
pmid = {31314099},
issn = {1574-6941},
abstract = {Ammonium-oxidizing archaea (AOA) and bacteria (AOB) play crucial roles in ammonium oxidation in freshwater lake sediment. However, previous reports on the predominance of AOA and AOB in the surface sediment of Lake Taihu have been based on DNA levels, detecting the total abundance of microbiota (including inactive cells), and have resulted in numerous contradictory conclusions. Existing RNA-level studies detecting active transcription are very limited. The current study, using RNA-based real-time quantification and clone library analysis, demonstrated that the amoA gene abundance of active AOB was higher than that of active AOA, despite conflicting results at the DNA level. Further exploration revealed a significant positive correlation between the potential nitrification rate (PNR) and the abundance of AOA and AOB at the RNA level, with irregular or contradictory correlation found at the DNA level. Ultimately, using quantitative analysis of RNA levels, we show AOB to be the active dominant contributor to ammonium oxidation. Our investigations also indicated that AOB were more diverse in high-ammonium lake regions, with Nitrosomonas being the active and dominating cluster, but that AOA had an advantage in the low-ammonium lake regions.},
}
@article {pmid31312729,
year = {2019},
author = {DeMott, MS and Dedon, PC},
title = {The road less traveled: A new phosphorothioate antiviral defense mechanism discovered in Archaea.},
journal = {Synthetic and systems biotechnology},
volume = {4},
number = {3},
pages = {132-133},
doi = {10.1016/j.synbio.2019.06.002},
pmid = {31312729},
issn = {2405-805X},
}
@article {pmid31283101,
year = {2019},
author = {Schwarz, TS and Wäber, NB and Feyh, R and Weidenbach, K and Schmitz, RA and Marchfelder, A and Hartmann, RK},
title = {Homologs of aquifex aeolicus protein-only RNase P are not the major RNase P activities in the archaea haloferax volcanii and methanosarcina mazei.},
journal = {IUBMB life},
volume = {71},
number = {8},
pages = {1109-1116},
doi = {10.1002/iub.2122},
pmid = {31283101},
issn = {1521-6551},
support = {DFG Schm 1052/9-3//Deutsche Forschungsgemeinschaft/ ; DFG Ma1538/21-1//Deutsche Forschungsgemeinschaft/ ; DFG HA 1672/19//Deutsche Forschungsgemeinschaft/ ; },
abstract = {The mature 5'-ends of tRNAs are generated by RNase P in all domains of life. The ancient form of the enzyme is a ribonucleoprotein consisting of a catalytic RNA and one or more protein subunits. However, in the hyperthermophilic bacterium Aquifex aeolicus and close relatives, RNase P is a protein-only enzyme consisting of a single type of polypeptide (Aq_880, ~23 kDa). In many archaea, homologs of Aq_880 were identified (termed HARPs for Homologs of Aquifex RNase P) in addition to the RNA-based RNase P, raising the question about the functions of HARP and the classical RNase P in these archaea. Here we investigated HARPs from two euryarchaeotes, Haloferax volcanii and Methanosarcina mazei. Archaeal strains with HARP gene knockouts showed no growth phenotypes under standard conditions, temperature and salt stress (H. volcanii) or nitrogen deficiency (M. mazei). Recombinant H. volcanii and M. mazei HARPs were basically able to catalyse specific tRNA 5'-end maturation in vitro. Furthermore, M. mazei HARP was able to rescue growth of an Escherichia coli RNase P depletion strain with comparable efficiency as Aq_880, while H. volcanii HARP was unable to do so. In conclusion, both archaeal HARPs showed the capacity (in at least one functional assay) to act as RNases P. However, the ease to obtain knockouts of the singular HARP genes and the lack of growth phenotypes upon HARP gene deletion contrasts with the findings that the canonical RNase P RNA gene cannot be deleted in H. volcanii, and a knockdown of RNase P RNA in H. volcanii results in severe tRNA processing defects. We conclude that archaeal HARPs do not make a major contribution to global tRNA 5'-end maturation in archaea, but may well exert a specialised, yet unknown function in (t)RNA metabolism. © 2019 IUBMB Life, 2019 © 2019 IUBMB Life, 71(8):1109-1116, 2019.},
}
@article {pmid31270201,
year = {2019},
author = {DasSarma, S and Fomenkov, A and DasSarma, SL and Vincze, T and DasSarma, P and Roberts, RJ},
title = {Methylomes of Two Extremely Halophilic Archaea Species, Haloarcula marismortui and Haloferax mediterranei.},
journal = {Microbiology resource announcements},
volume = {8},
number = {27},
pages = {},
doi = {10.1128/MRA.00577-19},
pmid = {31270201},
issn = {2576-098X},
abstract = {The genomes of two extremely halophilic Archaea species, Haloarcula marismortui and Haloferax mediterranei, were sequenced using single-molecule real-time sequencing. The ∼4-Mbp genomes are GC rich with multiple large plasmids and two 4-methyl-cytosine patterns. Methyl transferases were incorporated into the Restriction Enzymes Database (REBASE), and gene annotation was incorporated into the Haloarchaeal Genomes Database (HaloWeb).},
}
@article {pmid31264806,
year = {2019},
author = {Pereira, O and Hochart, C and Auguet, JC and Debroas, D and Galand, PE},
title = {Genomic ecology of Marine Group II, the most common marine planktonic Archaea across the surface ocean.},
journal = {MicrobiologyOpen},
volume = {},
number = {},
pages = {e852},
doi = {10.1002/mbo3.852},
pmid = {31264806},
issn = {2045-8827},
support = {ANR-14-CE02-0004-01//Agence Nationale de la Recherche/ ; },
abstract = {Planktonic Archaea have been detected in all the world's oceans and are found from surface waters to the deep sea. The two most common Archaea phyla are Thaumarchaeota and Euryarchaeota. Euryarchaeota are generally more common in surface waters, but very little is known about their ecology and their potential metabolisms. In this study, we explore the genomic ecology of the Marine Group II (MGII), the main marine planktonic Euryarchaeota, and test if it is composed of different ecologically relevant units. We re-analyzed Tara Oceans metagenomes from the photic layer and the deep ocean by annotating sequences against a custom MGII database and by mapping gene co-occurrences. Our data provide a global view of the distribution of Euryarchaeota, and more specifically of MGII subgroups, and reveal their association to a number of gene-coding sequences. In particular, we show that MGII proteorhodopsins were detected in both the surface and the deep chlorophyll maximum layer and that different clusters of these light harvesting proteins were present. Our approach helped describing the set of genes found together with specific MGII subgroups. We could thus define genomic environments that could theoretically describe ecologically meaningful units and the ecological niche that they occupy.},
}
@article {pmid31249623,
year = {2019},
author = {Zhao, X and Li, X and Li, Y and Sun, Y and Zhang, X and Weng, L and Ren, T and Li, Y},
title = {Shifting interactions among bacteria, fungi and archaea enhance removal of antibiotics and antibiotic resistance genes in the soil bioelectrochemical remediation.},
journal = {Biotechnology for biofuels},
volume = {12},
number = {},
pages = {160},
doi = {10.1186/s13068-019-1500-1},
pmid = {31249623},
issn = {1754-6834},
abstract = {Background: Antibiotics and antibiotic resistance genes (ARGs) are two pollutants in soil, especially ARGs as one of the top three threats to human health. The performance of soil microbial fuel cells (MFCs) fuelled with antibiotics was investigated.<br><br>Results: In this study, soil MFCs spiked with tetracycline exhibited optimal bioelectricity generation, which was 25% and 733% higher than those of MFCs spiked with sulfadiazine and control, respectively. Compared with the non-electrode treatment, not only did functional micro-organisms change in open- and closed-circuit treatments, but also the microbial affinities, respectively, increased by 50% and 340% to adapt to higher removal of antibiotics. For the open-circuit treatment, the ineffective interspecific relation of micro-organisms was reduced to assist the removal efficiency of antibiotics by 7-27%. For the closed-circuit treatment, an intensive metabolic network capable of bioelectricity generation, degradation and nitrogen transformation was established, which led to 10-35% higher removal of antibiotics. Importantly, the abundances of ARGs and mobile genetic element (MGE) genes decreased after the introduction of electrodes; especially in the closed-circuit treatment, the highest reduction of 47% and 53% was observed, respectively.<br><br>Conclusions: Soil MFCs possess advantages for the elimination of antibiotics and ARGs with sevenfold to eightfold higher electricity generation than that of the control treatment. Compared with sulphonamides, the enhancement removal of tetracycline is higher, while both potential ARG propagation risk is reduced in soil MFCs. This study firstly synchronously reveals the relationships among bacteria, fungi and archaea and with ARGs and MGE genes in soil bioelectrochemical systems.},
}
@article {pmid31249390,
year = {2019},
author = {Trivedi, C and Reich, PB and Maestre, FT and Hu, HW and Singh, BK and Delgado-Baquerizo, M},
title = {Plant-driven niche differentiation of ammonia-oxidizing bacteria and archaea in global drylands.},
journal = {The ISME journal},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41396-019-0465-1},
pmid = {31249390},
issn = {1751-7370},
abstract = {Under controlled laboratory conditions, high and low ammonium availability are known to favor soil ammonia-oxidizing bacteria (AOB) and archaea (AOA) communities, respectively. However, whether this niche segregation is maintained under field conditions in terrestrial ecosystems remains unresolved, particularly at the global scale. We hypothesized that perennial vegetation might favor AOB vs. AOA communities compared with adjacent open areas devoid of perennial vegetation (i.e., bare soil) via several mechanisms, including increasing the amount of ammonium in soil. To test this niche-differentiation hypothesis, we conducted a global field survey including 80 drylands from 6 continents. Data supported our hypothesis, as soils collected under plant canopies had higher levels of ammonium, as well as higher richness (number of terminal restriction fragments; T-RFs) and abundance (qPCR amoA genes) of AOB, and lower richness and abundance of AOA, than those collected in open areas located between plant canopies. Some of the reported associations between plant canopies and AOA and AOB communities can be a consequence of the higher organic matter and available N contents found under plant canopies. Other aspects of soils associated with vegetation including shading and microclimatic conditions might also help explain our results. Our findings provide strong evidence for niche differentiation between AOA and AOB communities in drylands worldwide, advancing our understanding of their ecology and biogeography at the global scale.},
}
@article {pmid31249385,
year = {2019},
author = {Zhang, H and Sun, H and Zhou, S and Bai, N and Zheng, X and Li, S and Zhang, J and Lv, W},
title = {Effect of Straw and Straw Biochar on the Community Structure and Diversity of Ammonia-oxidizing Bacteria and Archaea in Rice-wheat Rotation Ecosystems.},
journal = {Scientific reports},
volume = {9},
number = {1},
pages = {9367},
doi = {10.1038/s41598-019-45877-7},
pmid = {31249385},
issn = {2045-2322},
abstract = {Ammonia oxidation is the first and rate-limiting step of nitrification, driven by ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA). Straw and straw biochar retention are the popular ways to utilize the agricultural by-products in China, but their long-term effects on AOB and AOA still remain poorly understood. Based on a 7-year plot experiment, which had 4 fertilization regimes: no fertilizer (CK), regular fertilization (RT), straw retention (SR) and straw biochar retention (SB), the abundance and the composition of AOB and AOA was investigated before both the harvest of rice and wheat season by quantitative PCR and 454 high-throughput pyrosequencing, respectively. (1) Compared to RT, straw and straw biochar increased AOB abundance and diversity significantly only in wheat season (P < 0.05), and they both ranked as SB > SR > RT. Among fertilized treatments, a significant difference between SR and RT was found in AOB community composition of the winter season (R value = 0.58, P value = 0.02); (2) In contrast, AOA was almost not responsive to organic addition, except the significant enhancement of abundance by biochar in wheat season; (3) After straw and straw biochar addition, soil potential nitrification rates (PNR) was positive correlated to AOB abundance in both rice and wheat season (P < 0.01), not to AOA abundance (P = 0.211 and 0.068, respectively). This study provides scientific support for the potential of straw utilization to improve nitrification in rice-wheat rotation system with respect to soil ammonia oxidation microorganism.},
}
@article {pmid31239395,
year = {2019},
author = {Bayer, B and Pelikan, C and Bittner, MJ and Reinthaler, T and Könneke, M and Herndl, GJ and Offre, P},
title = {Proteomic Response of Three Marine Ammonia-Oxidizing Archaea to Hydrogen Peroxide and Their Metabolic Interactions with a Heterotrophic Alphaproteobacterium.},
journal = {mSystems},
volume = {4},
number = {4},
pages = {},
doi = {10.1128/mSystems.00181-19},
pmid = {31239395},
issn = {2379-5077},
abstract = {Ammonia-oxidizing archaea (AOA) play an important role in the nitrogen cycle and account for a considerable fraction of the prokaryotic plankton in the ocean. Most AOA lack the hydrogen peroxide (H2O2)-detoxifying enzyme catalase, and some AOA have been shown to grow poorly under conditions of exposure to H2O2 However, differences in the degrees of H2O2 sensitivity of different AOA strains, the physiological status of AOA cells exposed to H2O2, and their molecular response to H2O2 remain poorly characterized. Further, AOA might rely on heterotrophic bacteria to detoxify H2O2, and yet the extent and variety of costs and benefits involved in these interactions remain unclear. Here, we used a proteomics approach to compare the protein profiles of three Nitrosopumilus strains grown in the presence and absence of catalase and in coculture with the heterotrophic alphaproteobacterium Oceanicaulis alexandrii We observed that most proteins detected at a higher relative abundance in H2O2-exposed Nitrosopumilus cells had no known function in oxidative stress defense. Instead, these proteins were putatively involved in the remodeling of the extracellular matrix, which we hypothesize to be a strategy limiting the influx of H2O2 into the cells. Using RNA-stable isotope probing, we confirmed that O. alexandrii cells growing in coculture with the Nitrosopumilus strains assimilated Nitrosopumilus-derived organic carbon, suggesting that AOA could recruit H2O2-detoxifying bacteria through the release of labile organic matter. Our results contribute new insights into the response of AOA to H2O2 and highlight the potential ecological importance of their interactions with heterotrophic free-living bacteria in marine environments.IMPORTANCE Ammonia-oxidizing archaea (AOA) are the most abundant chemolithoautotrophic microorganisms in the oxygenated water column of the global ocean. Although H2O2 appears to be a universal by-product of aerobic metabolism, genes encoding the hydrogen peroxide (H2O2)-detoxifying enzyme catalase are largely absent in genomes of marine AOA. Here, we provide evidence that closely related marine AOA have different degrees of sensitivity to H2O2, which may contribute to niche differentiation between these organisms. Furthermore, our results suggest that marine AOA rely on H2O2 detoxification during periods of high metabolic activity and release organic compounds, thereby potentially attracting heterotrophic prokaryotes that provide this missing function. In summary, this report provides insights into the metabolic interactions between AOA and heterotrophic bacteria in marine environments and suggests that AOA play an important role in the biogeochemical carbon cycle by making organic carbon available for heterotrophic microorganisms.},
}
@article {pmid31237975,
year = {2019},
author = {Horai, S and Yamauchi, N and Naraoka, H},
title = {Simultaneous total analysis of core and polar membrane lipids in archaea by high-performance liquid chromatography/high-resolution mass spectrometry coupled with heated electrospray ionization.},
journal = {Rapid communications in mass spectrometry : RCM},
volume = {33},
number = {20},
pages = {1571-1577},
doi = {10.1002/rcm.8506},
pmid = {31237975},
issn = {1097-0231},
support = {KAKENHI Grant JP15H05749//Japan Society for the Promotion of Science/ ; },
abstract = {RATIONALE: Archaea have characteristic membrane lipids including diether and/or tetraether isoprenoidal core lipids with various polar head groups. Since the polar group is removed soon after the end of archaeal activity, the occurrences of core and polar lipids are regarded as dead and active signals, respectively. The core and polar lipids have generally been analyzed separately using atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI), respectively, coupled with mass spectrometry.<br><br>METHODS: In this study, simultaneous analyses of core and polar archaeal lipids have been examined using heated electrospray ionization (HESI) by high-performance liquid chromatography/high-resolution mass spectrometry (HPLC/HRMS).<br><br>RESULTS: Both core and intact polar lipids can be analyzed simultaneously by HESI with good sensitivity (sub ng to 100 ng) and separation using a semi-bore diol column by normal-phase chromatography. The core lipids eluted firstly to separate archeaol, then glycerol dibiphytanyl glycerol tetraethers (GDGTs), followed by the polar lipids with glycosides and glycophosphates. The relative GDGT composition is identical between HESI and APCI methods.<br><br>CONCLUSIONS: The simultaneous analysis has the benefit of minimizing sample amount and elution solvent as well as preparation work. The method can also be applied to a compound class fractionation for compound-specific carbon and hydrogen isotope analysis.},
}
@article {pmid31223656,
year = {2019},
author = {Vuillemin, A and Wankel, SD and Coskun, ÖK and Magritsch, T and Vargas, S and Estes, ER and Spivack, AJ and Smith, DC and Pockalny, R and Murray, RW and D'Hondt, S and Orsi, WD},
title = {Archaea dominate oxic subseafloor communities over multimillion-year time scales.},
journal = {Science advances},
volume = {5},
number = {6},
pages = {eaaw4108},
doi = {10.1126/sciadv.aaw4108},
pmid = {31223656},
issn = {2375-2548},
abstract = {Ammonia-oxidizing archaea (AOA) dominate microbial communities throughout oxic subseafloor sediment deposited over millions of years in the North Atlantic Ocean. Rates of nitrification correlated with the abundance of these dominant AOA populations, whose metabolism is characterized by ammonia oxidation, mixotrophic utilization of organic nitrogen, deamination, and the energetically efficient chemolithoautotrophic hydroxypropionate/hydroxybutyrate carbon fixation cycle. These AOA thus have the potential to couple mixotrophic and chemolithoautotrophic metabolism via mixotrophic deamination of organic nitrogen, followed by oxidation of the regenerated ammonia for additional energy to fuel carbon fixation. This metabolic feature likely reduces energy loss and improves AOA fitness under energy-starved, oxic conditions, thereby allowing them to outcompete other taxa for millions of years.},
}
@article {pmid31212151,
year = {2019},
author = {Zhang, X and Duan, P and Wu, Z and Xiong, Z},
title = {Aged biochar stimulated ammonia-oxidizing archaea and bacteria-derived N2O and NO production in an acidic vegetable soil.},
journal = {The Science of the total environment},
volume = {687},
number = {},
pages = {433-440},
doi = {10.1016/j.scitotenv.2019.06.128},
pmid = {31212151},
issn = {1879-1026},
abstract = {Both nitrous oxide (N2O) and nitric oxide (NO) emissions are typically high in greenhouse-based high N input vegetable soils. Biochar amendment has been widely recommended for mitigating soil N2O emissions in agriculture. However, knowledge of the regulatory mechanisms of fresh and aged biochar for both N2O and NO production during ammonia oxidation is lacking. Two vegetable soils with different pH values were used in aerobic incubation experiments with 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (PTIO), 1-octyne and acetylene. The relative importance of ammonia-oxidizing archaea (AOA) and bacteria (AOB) to N2O and NO production was investigated as influenced by fresh and aged biochar amendments. The results showed that AOA dominated N2O production in acidic soil, while AOB dominated N2O production in alkaline soil. Aged biochar stimulated both AOA- and AOB-derived N2O and NO production by 84.8 and 340%, respectively, in acidic soil but only increased AOA-derived N2O and NO production in alkaline soil. Fresh biochar amendment increased AOA- and AOB-derived NO in acidic soil and AOA-derived NO in alkaline soil but had negligible effects on AOA- and AOB-derived N2O in both soils. Fresh biochar decreased AOA-amoA but increased AOB-amoA gene abundances in acidic soil, whereas aged biochar increased AOA- and AOB-amoA gene abundances in both soils. These findings improved our understanding of N2O and NO production mechanisms under different biochar amendments in alkaline and acidic vegetable soils.},
}
@article {pmid31196534,
year = {2019},
author = {Kırtel, O and Lescrinier, E and Van den Ende, W and Toksoy Öner, E},
title = {Discovery of fructans in Archaea.},
journal = {Carbohydrate polymers},
volume = {220},
number = {},
pages = {149-156},
doi = {10.1016/j.carbpol.2019.05.064},
pmid = {31196534},
issn = {1879-1344},
abstract = {Fructans are fructose-based oligo- and polysaccharides derived from sucrose that occur in a plethora of Eubacteria and plants. While fructan-producing (fructanogenic) Eubacteria are abundant in hypersaline environments, fructan production by Archaea has never been reported before. Exopolysaccharides accumulated by various Archaea from the Halobacteria class (belonging to the genera of Halomicrobium, Haloferax and Natronococcus) originating from different locations on Earth were structurally characterized as either levans or inulins with varying branching degrees (10%-16%). Thus, we show for the first time in the literature that fructans are produced in all three domains of life, including Archaea. This proof of concept will not only provide insight into Archaeal glycans and evolution but it may also open new frontiers for innovative strategies to overcome the ever-increasing threat of excessive salinization.},
}
@article {pmid31195017,
year = {2019},
author = {Lemmens, L and Maklad, HR and Bervoets, I and Peeters, E},
title = {Transcription Regulators in Archaea: Homologies and Differences with Bacterial Regulators.},
journal = {Journal of molecular biology},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.jmb.2019.05.045},
pmid = {31195017},
issn = {1089-8638},
abstract = {The fitness and survival of prokaryotic microorganisms depends on their ability to adequately respond to environmental changes, sudden stress conditions and metabolic shifts. An important mechanism underlying this response is the regulation of gene expression mediated by transcription factors that are responsive to small-molecule ligands or other intracellular signals. Despite constituting a distinct domain of life from bacteria and harboring a eukaryotic-like basal transcription apparatus, it is well established that archaea have similar transcription factors pointing to the existence of shared ancestral proteins and to the occurrence of inter-domain horizontal gene transfer events. However, while global structural features of bacterial and archaeal transcription factors are indeed similar, other characteristics imply that archaeal regulators have undergone independent evolution. Here, we discuss the characteristics of Lrp/AsnC, MarR, ArsR/SmtB and TrmB families of transcription factors, which are the dominant families that constitute the transcription factor repertoire in archaea. We exemplify the evolutionary expansion of these families in archaeal lineages by emphasizing homologies and differences with bacterial counterparts in terms of ligand or signal response, physiological functions and mechanistic principles of regulation. As such, we aim to define future research approaches that enable further characterization of the functions and mechanisms of archaeal transcription factors.},
}
@article {pmid31189733,
year = {2019},
author = {Ludt, K and Soppa, J},
title = {Polyploidy in halophilic archaea: regulation, evolutionary advantages, and gene conversion.},
journal = {Biochemical Society transactions},
volume = {47},
number = {3},
pages = {933-944},
doi = {10.1042/BST20190256},
pmid = {31189733},
issn = {1470-8752},
abstract = {All analyzed haloarachea are polyploid. In addition, haloarchaea contain more than one type of chromosome, and thus the gene dosage can be regulated independently on different replicons. Haloarchaea and several additional archaea have more than one replication origin on their major chromosome, in stark contrast with bacteria, which have a single replication origin. Two of these replication origins of Haloferax volcanii have been studied in detail and turned out to have very different properties. The chromosome copy number appears to be regulated in response to growth phases and environmental factors. Archaea typically contain about two Origin Recognition Complex (ORC) proteins, which are homologous to eukaryotic ORC proteins. However, haloarchaea are the only archaeal group that contains a multitude of ORC proteins. All 16 ORC protein paralogs from H. volcanii are involved in chromosome copy number regulation. Polyploidy has many evolutionary advantages for haloarchaea, e.g. a high resistance to desiccation, survival over geological times, and the relaxation of cell cycle-specific replication control. A further advantage is the ability to grow in the absence of external phosphate while using the many genome copies as internal phosphate storage polymers. Very efficient gene conversion operates in haloarchaea and results in the unification of genome copies. Taken together, haloarchaea are excellent models to study many aspects of genome biology in prokaryotes, exhibiting properties that have not been found in bacteria.},
}
@article {pmid31184586,
year = {2019},
author = {Killelea, T and Palud, A and Akcha, F and Lemor, M and L'haridon, S and Godfroy, A and Henneke, G},
title = {The interplay at the replisome mitigates the impact of oxidative damage on the genetic integrity of hyperthermophilic Archaea.},
journal = {eLife},
volume = {8},
number = {},
pages = {},
doi = {10.7554/eLife.45320},
pmid = {31184586},
issn = {2050-084X},
support = {ANR-10-JCJC-1501-01//Agence Nationale de la Recherche/ ; },
abstract = {8-oxodeoxyguanosine (8-oxodG), a major oxidised base modification, has been investigated to study its impact on DNA replication in hyperthermophilic Archaea. Here we show that 8-oxodG is formed in the genome of growing cells, with elevated levels following exposure to oxidative stress. Functional characterisation of cell-free extracts and the DNA polymerisation enzymes, PolB, PolD, and the p41/p46 complex, alone or in the presence of accessory factors (PCNA and RPA) indicates that translesion synthesis occurs under replicative conditions. One of the major polymerisation effects was stalling, but each of the individual proteins could insert and extend past 8-oxodG with differing efficiencies. The introduction of RPA and PCNA influenced PolB and PolD in similar ways, yet provided a cumulative enhancement to the polymerisation performance of p41/p46. Overall, 8-oxodG translesion synthesis was seen to be potentially mutagenic leading to errors that are reminiscent of dA:8-oxodG base pairing.},
}
@article {pmid31170597,
year = {2019},
author = {Wang, W and Su, Y and Wang, B and Wang, Y and Zhuang, L and Zhu, G},
title = {Spatiotemporal shifts of ammonia-oxidizing archaea abundance and structure during the restoration of a multiple pond and plant-bed/ditch wetland.},
journal = {The Science of the total environment},
volume = {684},
number = {},
pages = {629-640},
doi = {10.1016/j.scitotenv.2019.04.415},
pmid = {31170597},
issn = {1879-1026},
mesh = {Ammonia/metabolism ; Archaea/classification/*physiology ; *Conservation of Natural Resources ; *Microbiota ; Oxidation-Reduction ; Population Dynamics ; Spatio-Temporal Analysis ; *Wetlands ; },
abstract = {Ammonia-oxidizing archaea (AOA) microorganisms have been increasingly found in aquatic and terrestrial environments. These microorganisms make vital contributions to ammonia oxidation in such systems. However, their community succession characteristics in man-made wetland ecosystems have scarcely been reported. We assessed the AOA's spatiotemporal shifts in the sediments of a constructed wetland (CW) - the Shijiuyang constructed wetland (SJY-CW) - in China from the third year (2011) to the fifth year (2013) of the CW operation. The SJY-CW is composed of a pretreatment pond, a multiple plant-bed/ditch system, and a post-treatment pond. Results showed that AOA abundance in the pre- and post-treatment ponds remained invariant through 2011-2012 and decreased in 2013, while the abundance in the plant-bed/ditch system decreased gradually with wetland operation. The AOA abundance in 2013 was one order of magnitude lower than that through 2011-2012, and the AOA abundance in the plant-bed/ditch system was generally higher than that in the pre- and post-treatment ponds from 2011 to 2013. AOA diversity showed little temporal differentiation with a slightly decreasing trend for community richness index Chao1 and diversity index Shannon H' from 2011 to 2013. The AOA community was dominated by the Nitrososphaera cluster accompanied by an increasing Nitrosopumilus cluster and Nitrososphaera sister cluster within the wetland operation. Hierarchical clustering and redundancy analysis verified the horizontal shifts of AOA communities. The shifts occurred preferentially in the central plant-bed/ditch system. The operational duration of the wetland became a key factor influencing AOA abundance and community shift in SJY-CW sediments.},
}
@article {pmid31150759,
year = {2019},
author = {Stachler, AE and Schwarz, TS and Schreiber, S and Marchfelder, A},
title = {CRISPRi as an efficient tool for gene repression in archaea.},
journal = {Methods (San Diego, Calif.)},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.ymeth.2019.05.023},
pmid = {31150759},
issn = {1095-9130},
abstract = {In the years following its discovery and characterization, the CRISPR-Cas system has been modified and converted into a multitude of applications for eukaryotes and bacteria, such as genome editing and gene regulation. Since no such method has been available for archaea, we developed a tool for gene repression in the haloarchaeon Haloferax volcanii by repurposing its endogenous type I-B CRISPR-Cas system. Here, we present the two possible approaches for gene repression as well as our workflow to achieve and assess gene knockdown, offer recommendations on protospacer selection and give some examples of genes we have successfully silenced.},
}
@article {pmid31150548,
year = {2019},
author = {Kurth, JM and Smit, NT and Berger, S and Schouten, S and Jetten, MSM and Welte, CU},
title = {Anaerobic methanotrophic archaea of the ANME-2d clade feature lipid composition that differs from other ANME archaea.},
journal = {FEMS microbiology ecology},
volume = {95},
number = {7},
pages = {},
doi = {10.1093/femsec/fiz082},
pmid = {31150548},
issn = {1574-6941},
abstract = {The anaerobic oxidation of methane (AOM) is a microbial process present in marine and freshwater environments. AOM is important for reducing the emission of the second most important greenhouse gas methane. In marine environments anaerobic methanotrophic archaea (ANME) are involved in sulfate-reducing AOM. In contrast, Ca. Methanoperedens of the ANME-2d cluster carries out nitrate AOM in freshwater ecosystems. Despite the importance of those organisms for AOM in non-marine environments little is known about their lipid composition or carbon sources. To close this gap, we analysed the lipid composition of ANME-2d archaea and found that they mainly synthesise archaeol and hydroxyarchaeol as well as different (hydroxy-) glycerol dialkyl glycerol tetraethers, albeit in much lower amounts. Abundant lipid headgroups were dihexose, monomethyl-phosphatidyl ethanolamine and phosphatidyl hexose. Moreover, a monopentose was detected as a lipid headgroup that is rare among microorganisms. Batch incubations with 13C labelled bicarbonate and methane showed that methane is the main carbon source of ANME-2d archaea varying from ANME-1 archaea that primarily assimilate dissolved inorganic carbon (DIC). ANME-2d archaea also assimilate DIC, but to a lower extent than methane. The lipid characterisation and analysis of the carbon source of Ca. Methanoperedens facilitates distinction between ANME-2d and other ANMEs.},
}
@article {pmid31147749,
year = {2019},
author = {Ijichi, M and Itoh, H and Hamasaki, K},
title = {Vertical distribution of particle-associated and free-living ammonia-oxidizing archaea in Suruga Bay, a deep coastal embayment of Japan.},
journal = {Archives of microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00203-019-01680-6},
pmid = {31147749},
issn = {1432-072X},
support = {JP24121004//Japan Society for the Promotion of Science/ ; },
abstract = {We analyzed the vertical distributions of ammonia-oxidizing archaea (AOA) in terms of abundance in Suruga Bay, Japan. We distinguished particle-associated (PA) from free-living (FL) assemblages. According to quantitative PCR measurements of the ammonia monooxygenase subunit A gene (amoA), most marine AOA were in an FL state. The vertical distributions of PA AOA ecotypes differed from the general trend; the Shallow Marine clade was dominant in both the surface and deep layers. Thus, although PA AOA account for a small percentage of AOA abundance, they have a community structure distinct from that of FL AOA in planktonic environments. Marine particles should be investigated further as an unexplored niche of AOA in the ocean.},
}
@article {pmid31136034,
year = {2019},
author = {Walsh, JC and Angstmann, CN and Bisson-Filho, AW and Garner, EC and Duggin, IG and Curmi, PMG},
title = {Division plane placement in pleomorphic archaea is dynamically coupled to cell shape.},
journal = {Molecular microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/mmi.14316},
pmid = {31136034},
issn = {1365-2958},
support = {DP2AI117923//National Institutes of Health/ ; Future Fellowship FT160100010//Australian Research Council/ ; 203276/Z/16/Z//Wellcome Trust/United Kingdom ; },
abstract = {One mechanism for achieving accurate placement of the cell division machinery is via Turing patterns, where nonlinear molecular interactions spontaneously produce spatiotemporal concentration gradients. The resulting patterns are dictated by cell shape. For example, the Min system of Escherichia coli shows spatiotemporal oscillation between cell poles, leaving a mid-cell zone for division. The universality of pattern-forming mechanisms in divisome placement is currently unclear. We examined the location of the division plane in two pleomorphic archaea, Haloferax volcanii and Haloarcula japonica, and showed that it correlates with the predictions of Turing patterning. Time-lapse analysis of H. volcanii shows that divisome locations after successive rounds of division are dynamically determined by daughter cell shape. For H. volcanii, we show that the location of DNA does not influence division plane location, ruling out nucleoid occlusion. Triangular cells provide a stringent test for Turing patterning, where there is a bifurcation in division plane orientation. For the two archaea examined, most triangular cells divide as predicted by a Turing mechanism; however, in some cases multiple division planes are observed resulting in cells dividing into three viable progeny. Our results suggest that the division site placement is consistent with a Turing patterning system in these archaea.},
}
@article {pmid31133998,
year = {2019},
author = {Zhang, R and Neu, TR and Li, Q and Blanchard, V and Zhang, Y and Schippers, A and Sand, W},
title = {Insight Into Interactions of Thermoacidophilic Archaea With Elemental Sulfur: Biofilm Dynamics and EPS Analysis.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {896},
doi = {10.3389/fmicb.2019.00896},
pmid = {31133998},
issn = {1664-302X},
abstract = {Biooxidation of reduced inorganic sulfur compounds (RISCs) by thermoacidophiles is of particular interest for the biomining industry and for environmental issues, e.g., formation of acid mine drainage (AMD). Up to now, interfacial interactions of acidophiles with elemental sulfur as well as the mechanisms of sulfur oxidation by acidophiles, especially thermoacidophiles, are not yet fully clear. This work focused on how a crenarchaeal isolate Acidianus sp. DSM 29099 interacts with elemental sulfur. Analysis by Confocal laser scanning microscopy (CLSM) and Atomic force microscopy (AFM) in combination with Epifluorescence microscopy (EFM) shows that biofilms on elemental sulfur are characterized by single colonies and a monolayer in first stage and later on 3-D structures with a diameter of up to 100 μm. The analysis of extracellular polymeric substances (EPS) by a non-destructive lectin approach (fluorescence lectin-barcoding analysis) using several fluorochromes shows that intial attachment was featured by footprints rich in biofilm cells that were embedded in an EPS matrix consisting of various glycoconjugates. Wet chemistry data indicate that carbohydrates, proteins, lipids and uronic acids are the main components. Attenuated reflectance (ATR)-Fourier transformation infrared spectroscopy (FTIR) and high-performance anion exchange chromatography with pulsed amperometric detection (HPAE-PAD) indicate glucose and mannose as the main monosaccharides in EPS polysaccharides. EPS composition as well as sugar types in EPS vary according to substrate (sulfur or tetrathionate) and lifestyle (biofilms and planktonic cells). This study provides information on the building blocks/make up as well as dynamics of biofilms of thermoacidophilic archaea in extremely acidic environments.},
}
@article {pmid31121445,
year = {2019},
author = {Zhang, L and Dong, H and Zhang, J and Chen, Y and Zeng, G and Yuan, Y and Cao, W and Fang, W and Hou, K and Wang, B and Li, L},
title = {Influence of FeONPs amendment on nitrogen conservation and microbial community succession during composting of agricultural waste: Relative contributions of ammonia-oxidizing bacteria and archaea to nitrogen conservation.},
journal = {Bioresource technology},
volume = {287},
number = {},
pages = {121463},
doi = {10.1016/j.biortech.2019.121463},
pmid = {31121445},
issn = {1873-2976},
abstract = {Composting amended with iron oxide nanoparticles (FeONPs, α-Fe2O3 and Fe3O4 NPs) were conducted to study the impacts of FeONPs on nitrogen conservation and microbial community. It was found that amendment of FeONPs, especially α-Fe2O3 NPs, reduced total nitrogen (TN) loss, and reserved more NH4+-N and mineral N. Pearson correlation analysis revealed that decrease of ammonia-oxidizing bacteria (AOB) in FeONPs treatments played more important role than ammonia-oxidizing archaea (AOA) in reserving more NH4+-N and mineral N, and reducing TN loss. Bacterial community composition at phylum level did not shift with addition of FeONPs. Firmicutes, Actinobacteria, and Proteobacteria were the three most dominant phyla in all treatments. Overall, this study provides a method to reduce TN loss and improve mineral N reservation during composting, and gives a deep insight into the role of AOB and AOA in nitrogen transformation.},
}
@article {pmid31089359,
year = {2019},
author = {Safarpour, A and Ebrahimi, M and Shahzadeh Fazeli, SA and Amoozegar, MA},
title = {Supernatant Metabolites from Halophilic Archaea to Reduce Tumorigenesis in Prostate Cancer In-vitro and In-vivo.},
journal = {Iranian journal of pharmaceutical research : IJPR},
volume = {18},
number = {1},
pages = {241-253},
pmid = {31089359},
issn = {1735-0328},
abstract = {Halophilic archaea are known as the novel producers of natural products and their supernatant metabolites could have cytotoxic effects on cancer cells. In the present study, we screened the anticancer potential of supernatant metabolites from eight native haloarchaeal strains obtained from a culture collection in Iran. Five human cancer cell lines including breast, lung, prostate and also human fibroblast cells as the normal control were used in the present study. Moreover, to evaluate the anti-tumor effect of the selected supernatant, inhibition of sphere formation and tumor development was assessed in-vitro and in-vivo, respectively. Among all strains, supernatant metabolites from Halobacterium salinarum IBRC M10715 had the most potent cytotoxic effect on prostate cancer cell lines (IC50 = 0.5 mg/mL) without any effects on normal cells. It significantly increased both early and late apoptosis (about 11% and 9%, respectively) in the androgen-dependent PC3 cell line, reduced sphere formation ability of DU145 and PC3 cells with down-regulation of SOX2 gene expression. Furthermore, our results revealed that tumors developed in nude mice significantly shrank post intratumor injection of metabolites of the haloarchaeal strain. In conclusion, we suggested here for the first time that supernatant metabolites from Halobacterium salinarum IBRC M10715 could be a novel component against prostate cancer in-vitro and in-vivo with remarkable reduction in stem-like properties of tumor.},
}
@article {pmid31085691,
year = {2019},
author = {Hepowit, NL and Maupin-Furlow, JA},
title = {Rhodanese-Like Domain Protein UbaC and Its Role in Ubiquitin-Like Protein Modification and Sulfur Mobilization in Archaea.},
journal = {Journal of bacteriology},
volume = {201},
number = {15},
pages = {},
doi = {10.1128/JB.00254-19},
pmid = {31085691},
issn = {1098-5530},
support = {R01 GM057498/GM/NIGMS NIH HHS/United States ; },
abstract = {Ubiquitin-like protein (Ubl) modification targets proteins for transient inactivation and/or proteasome-mediated degradation in archaea. Here the rhodanese-like domain (RHD) protein UbaC (HVO_1947) was found to copurify with the E1-like enzyme (UbaA) of the Ubl modification machinery in the archaeon Haloferax volcanii UbaC was shown to be important for Ubl ligation, particularly for the attachment of the Ubl SAMP2/3s to protein targets after exposure to oxidants (NaOCl, dimethyl sulfoxide [DMSO], and methionine sulfoxide [MetO]) and the proteasome inhibitor bortezomib. While UbaC was needed for ligation of the Ubl SAMP1 to MoaE (the large subunit of molybdopterin synthase), it was not important in the formation of oxidant-induced SAMP1 protein conjugates. Indicative of defects in sulfur relay, mutation of ubaC impaired molybdenum cofactor (Moco)-dependent DMSO reductase activity and cell survival at elevated temperature, suggesting a correlation with defects in the 2-thiolated state of wobble uridine tRNA. Overall, the archaeal stand-alone RHD UbaC has an important function in Ubl ligation and is associated with sulfur relay processes.IMPORTANCE Canonical E2 Ub/Ubl-conjugating enzymes are not conserved in the dual-function Ubl systems associated with protein modification and sulfur relay. Instead, the C-terminal RHDs of E1-RHD fusion proteins are the apparent E2 modules of these systems in eukaryotes. E1s that lack an RHD are common in archaea. Here we identified an RHD (UbaC) that serves as an apparent E2 analog with the E1-like UbaA in the dual-function Ubl sampylation system of archaea. Unlike the eukaryotic E1-RHD fusion, the archaeal RHD is a stand-alone protein. This new insight suggests that E1 function in Ubl pathways could be influenced by shifts in RHD abundance and/or competition with other protein partners in the cell.},
}
@article {pmid31069963,
year = {2019},
author = {Lu, S and Zhang, X and Chen, K and Chen, Z and Li, Y and Qi, Z and Shen, Y and Li, Z},
title = {The small subunit of DNA polymerase D (DP1) associates with GINS-GAN complex of the thermophilic archaea in Thermococcus sp. 4557.},
journal = {MicrobiologyOpen},
volume = {},
number = {},
pages = {e848},
doi = {10.1002/mbo3.848},
pmid = {31069963},
issn = {2045-8827},
support = {31500027//National Natural Science Foundation of China/ ; },
abstract = {The eukaryotic GINS, Cdc45, and minichromosome maintenance proteins form an essential complex that moves with the DNA replication fork. The GINS protein complex has also been reported to associate with DNA polymerase. In archaea, the third domain of life, DNA polymerase D (PolD) is essential for DNA replication, and the genes encoding PolDs exist only in the genomes of archaea. The archaeal GAN (GINS-associated nuclease) is believed to be a homolog of the eukaryotic Cdc45. In this study, we found that the Thermococcus sp. 4557 DP1 (small subunit of PolD) interacted with GINS15 in vitro, and the 3'-5' exonuclease activity of DP1 was inhibited by GINS15. We also demonstrated that the GAN, GINS15, and DP1 proteins interact to form a complex adapting a GAN-GINS15-DP1 order. The results of this study imply that the complex constitutes a core of the DNA replisome in archaea.},
}
@article {pmid31064832,
year = {2019},
author = {Makarova, KS and Wolf, YI and Karamycheva, S and Zhang, D and Aravind, L and Koonin, EV},
title = {Antimicrobial Peptides, Polymorphic Toxins, and Self-Nonself Recognition Systems in Archaea: an Untapped Armory for Intermicrobial Conflicts.},
journal = {mBio},
volume = {10},
number = {3},
pages = {},
doi = {10.1128/mBio.00715-19},
pmid = {31064832},
issn = {2150-7511},
mesh = {Amino Acid Sequence ; Antimicrobial Cationic Peptides/*genetics ; Archaea/*genetics ; Archaeal Proteins/*genetics ; Bacterial Proteins/genetics ; Evolution, Molecular ; *Genome, Archaeal ; Genome, Bacterial ; Genomics ; Microbial Interactions ; Toxins, Biological/*genetics ; },
abstract = {Numerous, diverse, highly variable defense and offense genetic systems are encoded in most bacterial genomes and are involved in various forms of conflict among competing microbes or their eukaryotic hosts. Here we focus on the offense and self-versus-nonself discrimination systems encoded by archaeal genomes that so far have remained largely uncharacterized and unannotated. Specifically, we analyze archaeal genomic loci encoding polymorphic and related toxin systems and ribosomally synthesized antimicrobial peptides. Using sensitive methods for sequence comparison and the &quot;guilt by association&quot; approach, we identified such systems in 141 archaeal genomes. These toxins can be classified into four major groups based on the structure of the components involved in the toxin delivery. The toxin domains are often shared between and within each system. We revisit halocin families and substantially expand the halocin C8 family, which was identified in diverse archaeal genomes and also certain bacteria. Finally, we employ features of protein sequences and genomic locus organization characteristic of archaeocins and polymorphic toxins to identify candidates for analogous but not necessarily homologous systems among uncharacterized protein families. This work confidently predicts that more than 1,600 archaeal proteins, currently annotated as &quot;hypothetical&quot; in public databases, are components of conflict and self-versus-nonself discrimination systems.IMPORTANCE Diverse and highly variable systems involved in biological conflicts and self-versus-nonself discrimination are ubiquitous in bacteria but much less studied in archaea. We performed comprehensive comparative genomic analyses of the archaeal systems that share components with analogous bacterial systems and propose an approach to identify new systems that could be involved in these functions. We predict polymorphic toxin systems in 141 archaeal genomes and identify new, archaea-specific toxin and immunity protein families. These systems are widely represented in archaea and are predicted to play major roles in interactions between species and in intermicrobial conflicts. This work is expected to stimulate experimental research to advance the understanding of poorly characterized major aspects of archaeal biology.},
}
@article {pmid31064826,
year = {2019},
author = {Li, Z and Kinosita, Y and Rodriguez-Franco, M and Nußbaum, P and Braun, F and Delpech, F and Quax, TEF and Albers, SV},
title = {Positioning of the Motility Machinery in Halophilic Archaea.},
journal = {mBio},
volume = {10},
number = {3},
pages = {},
doi = {10.1128/mBio.00377-19},
pmid = {31064826},
issn = {2150-7511},
mesh = {Archaeal Proteins/*chemistry ; *Cell Polarity ; *Chemotaxis ; Cytoplasm/chemistry ; Flagella/physiology ; Haloferax volcanii/*physiology/ultrastructure ; Microscopy, Electron ; Time-Lapse Imaging ; },
abstract = {Bacteria and archaea exhibit tactical behavior and can move up and down chemical gradients. This tactical behavior relies on a motility structure, which is guided by a chemosensory system. Environmental signals are sensed by membrane-inserted chemosensory receptors that are organized in large ordered arrays. While the cellular positioning of the chemotaxis machinery and that of the flagellum have been studied in detail in bacteria, we have little knowledge about the localization of such macromolecular assemblies in archaea. Although the archaeal motility structure, the archaellum, is fundamentally different from the flagellum, archaea have received the chemosensory machinery from bacteria and have connected this system with the archaellum. Here, we applied a combination of time-lapse imaging and fluorescence and electron microscopy using the model euryarchaeon Haloferax volcanii and found that archaella were specifically present at the cell poles of actively dividing rod-shaped cells. The chemosensory arrays also had a polar preference, but in addition, several smaller arrays moved freely in the lateral membranes. In the stationary phase, rod-shaped cells became round and chemosensory arrays were disassembled. The positioning of archaella and that of chemosensory arrays are not interdependent and likely require an independent form of positioning machinery. This work showed that, in the rod-shaped haloarchaeal cells, the positioning of the archaellum and of the chemosensory arrays is regulated in time and in space. These insights into the cellular organization of H. volcanii suggest the presence of an active mechanism responsible for the positioning of macromolecular protein complexes in archaea.IMPORTANCE Archaea are ubiquitous single cellular microorganisms that play important ecological roles in nature. The intracellular organization of archaeal cells is among the unresolved mysteries of archaeal biology. With this work, we show that cells of haloarchaea are polarized. The cellular positioning of proteins involved in chemotaxis and motility is spatially and temporally organized in these cells. This suggests the presence of a specific mechanism responsible for the positioning of macromolecular protein complexes in archaea.},
}
@article {pmid31058146,
year = {2019},
author = {Isupov, MN and Boyko, KM and Sutter, JM and James, P and Sayer, C and Schmidt, M and Schönheit, P and Nikolaeva, AY and Stekhanova, TN and Mardanov, AV and Ravin, NV and Bezsudnova, EY and Popov, VO and Littlechild, JA},
title = {Corrigendum: Thermostable Branched-Chain Amino Acid Transaminases From the Archaea Geoglobus acetivorans and Archaeoglobus fulgidus: Biochemical and Structural Characterization.},
journal = {Frontiers in bioengineering and biotechnology},
volume = {7},
number = {},
pages = {79},
doi = {10.3389/fbioe.2019.00079},
pmid = {31058146},
issn = {2296-4185},
abstract = {[This corrects the article DOI: 10.3389/fbioe.2019.00007.].},
}
@article {pmid31048384,
year = {2019},
author = {Webster, G and Mullins, AJ and Watkins, AJ and Cunningham-Oakes, E and Weightman, AJ and Mahenthiralingam, E and Sass, H},
title = {Genome Sequences of Two Choline-Utilizing Methanogenic Archaea, Methanococcoides spp., Isolated from Marine Sediments.},
journal = {Microbiology resource announcements},
volume = {8},
number = {18},
pages = {},
doi = {10.1128/MRA.00342-19},
pmid = {31048384},
issn = {2576-098X},
support = {//Wellcome Trust/United Kingdom ; },
abstract = {The genomes of two Methanococcoides spp. that were isolated from marine sediments and are capable of carrying out methanogenesis from choline and other methylotrophic substrates were sequenced. The average nucleotide identity and in silico DNA-DNA hybridization analyses demonstrate that they represent species different from those previously described.},
}
@article {pmid31020937,
year = {2019},
author = {Gupta, A and Swati, D},
title = {Riboswitches in Archaea.},
journal = {Combinatorial chemistry &amp; high throughput screening},
volume = {22},
number = {2},
pages = {135-149},
doi = {10.2174/1386207322666190425143301},
pmid = {31020937},
issn = {1875-5402},
abstract = {BACKGROUND: Riboswitches are cis-acting, non-coding RNA elements found in the 5'UTR of bacterial mRNA and 3' UTR of eukaryotic mRNA, that fold in a complex manner to act as receptors for specific metabolites hence altering their conformation in response to the change in concentrations of a ligand or metabolite. Riboswitches function as gene regulators in numerous bacteria, archaea, fungi, algae and plants.<br><br>AIM AND OBJECTIVE: This study identifies different classes of riboswitches in the Archaeal domain of life. Previous studies have suggested that riboswitches carry a conserved aptameric domain in different domains of life. Since Archaea are considered to be the most idiosyncratic organisms it was interesting to look for the conservation pattern of riboswitches in these obviously strange microorganisms.<br><br>MATERIALS AND METHODS: Completely sequenced Archaeal Genomes present in the NCBI repository were used for studying riboswitches and other ncRNAs. The sequence files in FASTA format were downloaded from NCBI Genome database and information related to these genomes was retrieved from GenBank. Three bioinformatics approaches were used namely, ab initio, consensus structure prediction and statistical model-based prediction for identifying riboswitches.<br><br>RESULTS: Archaeal genomes have a sporadic distribution of putative riboswitches like the TPP, FMN, Guanidine, Lysine and c-di-AMP riboswitches, which are known to occur in bacteria. Also, a class of riboswitch sensing c-di-GMP, a second messenger, has been identified in a few Archaeal organisms.<br><br>CONCLUSION: This study clearly reveals that bioinformatics methods are likely to play a major role in identifying conserved riboswitches and in establishing how widespread these classes are in all domains of life, even though the final confirmation may come from wet lab methods.},
}
@article {pmid31016969,
year = {2019},
author = {Cândido, ES and Cardoso, MH and Chan, LY and Torres, MDT and Oshiro, KGN and Porto, WF and Ribeiro, SM and Haney, EF and Hancock, REW and Lu, TK and de la Fuente-Nunez, C and Craik, DJ and Franco, OL},
title = {Short Cationic Peptide Derived from Archaea with Dual Antibacterial Properties and Anti-Infective Potential.},
journal = {ACS infectious diseases},
volume = {5},
number = {7},
pages = {1081-1086},
doi = {10.1021/acsinfecdis.9b00073},
pmid = {31016969},
issn = {2373-8227},
abstract = {Bacterial biofilms and associated infections represent one of the biggest challenges in the clinic, and as an alternative to counter bacterial infections, antimicrobial peptides have attracted great attention in the past decade. Here, ten short cationic antimicrobial peptides were generated through a sliding-window strategy on the basis of the 19-amino acid residue peptide, derived from a Pyrobaculum aerophilum ribosomal protein. PaDBS1R6F10 exhibited anti-infective potential as it decreased the bacterial burden in murine Pseudomonas aeruginosa cutaneous infections by more than 1000-fold. Adverse cytotoxic and hemolytic effects were not detected against mammalian cells. The peptide demonstrated structural plasticity in terms of its secondary structure in the different environments tested. PaDBS1R6F10 represents a promising antimicrobial agent against bacteria infections, without harming human cells.},
}
@article {pmid31015799,
year = {2019},
author = {Wemheuer, F and von Hoyningen-Huene, AJE and Pohlner, M and Degenhardt, J and Engelen, B and Daniel, R and Wemheuer, B},
title = {Primary Production in the Water Column as Major Structuring Element of the Biogeographical Distribution and Function of Archaea in Deep-Sea Sediments of the Central Pacific Ocean.},
journal = {Archaea (Vancouver, B.C.)},
volume = {2019},
number = {},
pages = {3717239},
doi = {10.1155/2019/3717239},
pmid = {31015799},
issn = {1472-3654},
abstract = {Information on environmental conditions shaping archaeal communities thriving at the seafloor of the central Pacific Ocean is limited. The present study was conducted to investigate the diversity, composition, and function of both entire and potentially active archaeal communities within Pacific deep-sea sediments. For this purpose, sediment samples were taken along the 180° meridian of the central Pacific Ocean. Community composition and diversity were assessed by Illumina tag sequencing targeting archaeal 16S rRNA genes and transcripts. Archaeal communities were dominated by Candidatus Nitrosopumilus (Thaumarchaeota) and other members of the Nitrosopumilaceae (Thaumarchaeota), but higher relative abundances of the Marine Group II (Euryarchaeota) were observed in the active compared to the entire archaeal community. The composition of the entire and the active archaeal communities was strongly linked to primary production (chlorophyll content), explaining more than 40% of the variance. Furthermore, we found a strong correlation of the entire archaeal community composition to latitude and silicic acid content, while the active community was significantly correlated with primary production and ferric oxide content. We predicted functional profiles from 16S rRNA data to assess archaeal community functions. Latitude was significantly correlated with functional profiles of the entire community, whereas those of the active community were significantly correlated with nitrate and chlorophyll content. The results of the present study provide first insights into benthic archaeal communities in the Pacific Ocean and environmental conditions shaping their diversity, distribution, and function. Additionally, they might serve as a template for further studies investigating archaea colonizing deep-sea sediments.},
}
@article {pmid31015394,
year = {2019},
author = {Seitz, KW and Dombrowski, N and Eme, L and Spang, A and Lombard, J and Sieber, JR and Teske, AP and Ettema, TJG and Baker, BJ},
title = {Asgard archaea capable of anaerobic hydrocarbon cycling.},
journal = {Nature communications},
volume = {10},
number = {1},
pages = {1822},
doi = {10.1038/s41467-019-09364-x},
pmid = {31015394},
issn = {2041-1723},
support = {OCE-0647633//National Science Foundation/International ; OCE-1357238//National Science Foundation/International ; DE-AC02-05CH11231//US Department of Energy/International ; },
mesh = {Anaerobiosis ; Archaea/genetics/*metabolism ; Archaeal Proteins/genetics/*metabolism ; Genome, Archaeal/*genetics ; Geologic Sediments/microbiology ; Hydrocarbons/*metabolism ; Hydrothermal Vents/microbiology ; Metabolic Networks and Pathways/genetics ; Metagenomics ; Oceans and Seas ; Oxidoreductases/genetics/*metabolism ; Phylogeny ; },
abstract = {Large reservoirs of natural gas in the oceanic subsurface sustain complex communities of anaerobic microbes, including archaeal lineages with potential to mediate oxidation of hydrocarbons such as methane and butane. Here we describe a previously unknown archaeal phylum, Helarchaeota, belonging to the Asgard superphylum and with the potential for hydrocarbon oxidation. We reconstruct Helarchaeota genomes from metagenomic data derived from hydrothermal deep-sea sediments in the hydrocarbon-rich Guaymas Basin. The genomes encode methyl-CoM reductase-like enzymes that are similar to those found in butane-oxidizing archaea, as well as several enzymes potentially involved in alkyl-CoA oxidation and the Wood-Ljungdahl pathway. We suggest that members of the Helarchaeota have the potential to activate and subsequently anaerobically oxidize hydrothermally generated short-chain hydrocarbons.},
}
@article {pmid31000700,
year = {2019},
author = {Dong, X and Greening, C and Rattray, JE and Chakraborty, A and Chuvochina, M and Mayumi, D and Dolfing, J and Li, C and Brooks, JM and Bernard, BB and Groves, RA and Lewis, IA and Hubert, CRJ},
title = {Metabolic potential of uncultured bacteria and archaea associated with petroleum seepage in deep-sea sediments.},
journal = {Nature communications},
volume = {10},
number = {1},
pages = {1816},
doi = {10.1038/s41467-019-09747-0},
pmid = {31000700},
issn = {2041-1723},
mesh = {Acetates/metabolism ; Archaea/genetics/isolation &amp; purification/*metabolism ; Bacteria/genetics/isolation &amp; purification/*metabolism ; Geologic Sediments/chemistry/*microbiology ; Hydrocarbons/metabolism ; Hydrogen/metabolism ; Metagenome ; Metagenomics/methods ; Mexico ; Microbial Interactions/physiology ; Microbiota/*physiology ; Petroleum/*metabolism ; },
abstract = {The lack of microbial genomes and isolates from the deep seabed means that very little is known about the ecology of this vast habitat. Here, we investigate energy and carbon acquisition strategies of microbial communities from three deep seabed petroleum seeps (3 km water depth) in the Eastern Gulf of Mexico. Shotgun metagenomic analysis reveals that each sediment harbors diverse communities of chemoheterotrophs and chemolithotrophs. We recovered 82 metagenome-assembled genomes affiliated with 21 different archaeal and bacterial phyla. Multiple genomes encode enzymes for anaerobic oxidation of aliphatic and aromatic compounds, including those of candidate phyla Aerophobetes, Aminicenantes, TA06 and Bathyarchaeota. Microbial interactions are predicted to be driven by acetate and molecular hydrogen. These findings are supported by sediment geochemistry, metabolomics, and thermodynamic modelling. Overall, we infer that deep-sea sediments experiencing thermogenic hydrocarbon inputs harbor phylogenetically and functionally diverse communities potentially sustained through anaerobic hydrocarbon, acetate and hydrogen metabolism.},
}
@article {pmid30997302,
year = {2019},
author = {Verma, S and Kumar, R and Meghwanshi, GK},
title = {Identification of new members of alkaliphilic lipases in archaea and metagenome database using reconstruction of ancestral sequences.},
journal = {3 Biotech},
volume = {9},
number = {5},
pages = {165},
doi = {10.1007/s13205-019-1693-9},
pmid = {30997302},
issn = {2190-572X},
abstract = {The application of bioinformatics in lipase research has the potential to discover robust members from different genomic/metagenomic databses. In this study, we explored the diversity and distribution of alkaliphilic lipases in archaea domain and metagenome data sets through phylogenetic survey. Reconstructed ancestral sequence of alkaphilic lipase was used to search the homologous alkaliphilic lipases among the archaea and metagenome public databases. Our investigation revealed a total 21 unique sequences of new alkaliphilic lipases in the archaeal and environmental metagenomic protein databases that shared significant sequence similarity to the bacterial alkaliphilic lipases. Most of the identified new members of alkaliphilic lipases belong to class Haloarchaea. The searched list of homologs also comprised of one characterized lipase from alkalohyperthermophilic Archaeoglobus fulgidus. All the newly identified alkaliphilic lipase members showed conserved pentapeptide [X-His-Ser-X-Gly] motif, a key feature of lipase family. Furthermore, detailed analysis of all these new sequences showed homology either with thermostable or alkalophilic lipases. The reconstructed ancestral sequence-based searches increased the sensitivity and efficacies to detect remotely homologous sequences. We hypothesize that this study can enrich our current knowledge on lipases in designing more potential thermo-alkaliphilic lipases for industrial applications.},
}
@article {pmid30995692,
year = {2019},
author = {Langer, SG and Gabris, C and Einfalt, D and Wemheuer, B and Kazda, M and Bengelsdorf, FR},
title = {Different response of bacteria, archaea and fungi to process parameters in nine full-scale anaerobic digesters.},
journal = {Microbial biotechnology},
volume = {},
number = {},
pages = {},
doi = {10.1111/1751-7915.13409},
pmid = {30995692},
issn = {1751-7915},
abstract = {Biogas production is a biotechnological process realized by complex bacterial, archaeal and likely fungal communities. Their composition was assessed in nine full-scale biogas plants with distinctly differing feedstock input and process parameters. This study investigated the actually active microbial community members by using a comprehensive sequencing approach based on ribosomal 16S and 28S rRNA fragments. The prevailing taxonomical units of each respective community were subsequently linked to process parameters. Ribosomal rRNA of bacteria, archaea and fungi, respectively, showed different compositions with respect to process parameters and supplied feedstocks: (i) bacterial communities were affected by the key factors temperature and ammonium concentration; (ii) composition of archaea was mainly related to process temperature; and (iii) relative abundance of fungi was linked to feedstocks supplied to the digesters. Anaerobic digesters with a high methane yield showed remarkably similar bacterial communities regarding identified taxonomic families. Although archaeal communities differed strongly on genus level from each other, the respective digesters still showed high methane yields. Functional redundancy of the archaeal communities may explain this effect. 28S rRNA sequences of fungi in all nine full-scale anaerobic digesters were primarily classified as facultative anaerobic Ascomycota and Basidiomycota. Since the presence of ribosomal 28S rRNA indicates that fungi may be active in the biogas digesters, further research should be carried out to examine to which extent they are important players in anaerobic digestion processes.},
}
@article {pmid30994930,
year = {2019},
author = {Gomes-Filho, JV and Randau, L},
title = {RNA stabilization in hyperthermophilic archaea.},
journal = {Annals of the New York Academy of Sciences},
volume = {1447},
number = {1},
pages = {88-96},
doi = {10.1111/nyas.14060},
pmid = {30994930},
issn = {1749-6632},
support = {RA 2169/3-1//Deutsche Forschungsgemeinschaft/ ; },
abstract = {Analyses of the RNA metabolism of hyperthermophilic archaea highlight the efficiency of regulatory RNAs and RNA-guided processes at extreme temperatures. These organisms must overcome the intrinsic thermolability of RNAs. Elevated levels of RNA modifications and structured GC-rich regions are observed for many universal noncoding RNA families. Guide RNAs are often protected from degradation by their presence within ribonucleoprotein complexes. Modification and ligation of RNA termini can be employed to impair exonucleolytic degradation. Finally, antisense strand transcription promotes the formation of RNA duplexes and can be used to stabilize RNA regions. In our review, we provide examples of these RNA stabilization mechanisms that have been observed in hyperthermophilic archaeal model organisms.},
}
@article {pmid30991941,
year = {2019},
author = {Santos-Zavaleta, A and Pérez-Rueda, E and Sánchez-Pérez, M and Velázquez-Ramírez, DA and Collado-Vides, J},
title = {Tracing the phylogenetic history of the Crl regulon through the Bacteria and Archaea genomes.},
journal = {BMC genomics},
volume = {20},
number = {1},
pages = {299},
doi = {10.1186/s12864-019-5619-z},
pmid = {30991941},
issn = {1471-2164},
support = {R01GM110597//Foundation for the National Institutes of Health/ ; PAPIIT IN-201117//Dirección General de Asuntos del Personal Académico, Universidad Nacional Autónoma de México (MX)/ ; R01 GM110597/GM/NIGMS NIH HHS/United States ; U24GM077678//Foundation for the National Institutes of Health/ ; U24 GM077678/GM/NIGMS NIH HHS/United States ; },
mesh = {Evolution, Molecular ; Genome, Archaeal/*genetics ; Genome, Bacterial/*genetics ; *Phylogeny ; Regulon/*genetics ; },
abstract = {BACKGROUND: Crl, identified for curli production, is a small transcription factor that stimulates the association of the σS factor (RpoS) with the RNA polymerase core through direct and specific interactions, increasing the transcription rate of genes during the transition from exponential to stationary phase at low temperatures, using indole as an effector molecule. The lack of a comprehensive collection of information on the Crl regulon makes it difficult to identify a dominant function of Crl and to generate any hypotheses concerning its taxonomical distribution in archaeal and bacterial organisms.<br><br>RESULTS: In this work, based on a systematic literature review, we identified the first comprehensive dataset of 86 genes under the control of Crl in the bacterium Escherichia coli K-12; those genes correspond to 40% of the σS regulon in this bacterium. Based on an analysis of orthologs in 18 archaeal and 69 bacterial taxonomical divisions and using E. coli K-12 as a framework, we suggest three main events that resulted in this regulon's actual form: (i) in a first step, rpoS, a gene widely distributed in bacteria and archaea cellular domains, was recruited to regulate genes involved in ancient metabolic processes, such as those associated with glycolysis and the tricarboxylic acid cycle; (ii) in a second step, the regulon recruited those genes involved in metabolic processes, which are mainly taxonomically constrained to Proteobacteria, with some secondary losses, such as those genes involved in responses to stress or starvation and cell adhesion, among others; and (iii) in a posterior step, Crl might have been recruited in Enterobacteriaceae; because its taxonomical pattern constrained to this bacterial order, however further analysis are necessary.<br><br>CONCLUSIONS: Therefore, we suggest that the regulon Crl is highly flexible for phenotypic adaptation, probably as consequence of the diverse growth environments associated with all organisms in which members of this regulatory network are present.},
}
@article {pmid30991368,
year = {2019},
author = {Eggenberger, OM and Leriche, G and Koyanagi, T and Ying, C and Houghtaling, J and Schroeder, TBH and Yang, J and Li, J and Hall, A and Mayer, M},
title = {Fluid surface coatings for solid-state nanopores: comparison of phospholipid bilayers and archaea-inspired lipid monolayers.},
journal = {Nanotechnology},
volume = {30},
number = {32},
pages = {325504},
doi = {10.1088/1361-6528/ab19e6},
pmid = {30991368},
issn = {1361-6528},
abstract = {In the context of sensing and characterizing single proteins with synthetic nanopores, lipid bilayer coatings provide at least four benefits: first, they minimize unwanted protein adhesion to the pore walls by exposing a zwitterionic, fluid surface. Second, they can slow down protein translocation and rotation by the opportunity to tether proteins with a lipid anchor to the fluid bilayer coating. Third, they provide the possibility to impart analyte specificity by including lipid anchors with a specific receptor or ligand in the coating. Fourth, they offer a method for tuning nanopore diameters by choice of the length of the lipid's acyl chains. The work presented here compares four properties of various lipid compositions with regard to their suitability as nanopore coatings for protein sensing experiments: (1) electrical noise during current recordings through solid-state nanopores before and after lipid coating, (2) long-term stability of the recorded current baseline and, by inference, of the coating, (3) viscosity of the coating as quantified by the lateral diffusion coefficient of lipids in the coating, and (4) the success rate of generating a suitable coating for quantitative nanopore-based resistive pulse recordings. We surveyed lipid coatings prepared from bolaamphiphilic, monolayer-forming lipids inspired by extremophile archaea and compared them to typical bilayer-forming phosphatidylcholine lipids containing various fractions of curvature-inducing lipids or cholesterol. We found that coatings from archaea-inspired lipids provide several advantages compared to conventional phospholipids; the stable, low noise baseline qualities and high viscosity make these membranes especially suitable for analysis that estimates physical protein parameters such as the net charge of proteins as they enable translocation events with sufficiently long duration to time-resolve dwell time distributions completely. The work presented here reveals that the ease or difficulty of coating a nanopore with lipid membranes did not depend significantly on the composition of the lipid mixture, but rather on the geometry and surface chemistry of the nanopore in the solid state substrate. In particular, annealing substrates containing the nanopore increased the success rate of generating stable lipid coatings.},
}
@article {pmid30975999,
year = {2019},
author = {Xiong, L and Liu, S and Chen, S and Xiao, Y and Zhu, B and Gao, Y and Zhang, Y and Chen, B and Luo, J and Deng, Z and Chen, X and Wang, L and Chen, S},
title = {A new type of DNA phosphorothioation-based antiviral system in archaea.},
journal = {Nature communications},
volume = {10},
number = {1},
pages = {1688},
doi = {10.1038/s41467-019-09390-9},
pmid = {30975999},
issn = {2041-1723},
mesh = {Archaea/*physiology/virology ; Archaeal Proteins/genetics/immunology/*metabolism ; Archaeal Viruses/*genetics/pathogenicity ; DNA Replication/immunology ; DNA, Viral/*metabolism ; Gene Transfer, Horizontal/immunology ; Host Microbial Interactions/*genetics ; Immunity, Innate/genetics/immunology ; Phosphorothioate Oligonucleotides/metabolism ; RNA, Archaeal/genetics/isolation &amp; purification ; Sequence Analysis, DNA ; },
abstract = {Archaea and Bacteria have evolved different defence strategies that target virtually all steps of the viral life cycle. The diversified virion morphotypes and genome contents of archaeal viruses result in a highly complex array of archaea-virus interactions. However, our understanding of archaeal antiviral activities lags far behind our knowledges of those in bacteria. Here we report a new archaeal defence system that involves DndCDEA-specific DNA phosphorothioate (PT) modification and the PbeABCD-mediated halt of virus propagation via inhibition of DNA replication. In contrast to the breakage of invasive DNA by DndFGH in bacteria, DndCDEA-PbeABCD does not degrade or cleave viral DNA. The PbeABCD-mediated PT defence system is widespread and exhibits extensive interdomain and intradomain gene transfer events. Our results suggest that DndCDEA-PbeABCD is a new type of PT-based virus resistance system, expanding the known arsenal of defence systems as well as our understanding of host-virus interactions.},
}
@article {pmid30938665,
year = {2019},
author = {Bayer, B and Vojvoda, J and Reinthaler, T and Reyes, C and Pinto, M and Herndl, GJ},
title = {Nitrosopumilus adriaticus sp. nov. and Nitrosopumilus piranensis sp. nov., two ammonia-oxidizing archaea from the Adriatic Sea and members of the class Nitrososphaeria.},
journal = {International journal of systematic and evolutionary microbiology},
volume = {69},
number = {7},
pages = {1892-1902},
doi = {10.1099/ijsem.0.003360},
pmid = {30938665},
issn = {1466-5034},
mesh = {Ammonia/*metabolism ; Archaea/*classification/isolation &amp; purification ; Base Composition ; DNA, Archaeal/genetics ; Glyceryl Ethers/chemistry ; Hydrogen Peroxide ; Oceans and Seas ; Oxidation-Reduction ; *Phylogeny ; RNA, Ribosomal, 16S/genetics ; Seawater/*microbiology ; Sequence Analysis, DNA ; Vitamin K 2/analogs &amp; derivatives/chemistry ; },
abstract = {Two mesophilic, neutrophilic and aerobic marine ammonia-oxidizing archaea, designated strains NF5T and D3CT, were isolated from coastal surface water of the Northern Adriatic Sea. Cells were straight small rods 0.20-0.25 µm wide and 0.49-2.00 µm long. Strain NF5T possessed archaella as cell appendages. Glycerol dibiphytanyl glycerol tetraethers with zero to four cyclopentane moieties (GDGT-0 to GDGT-4) and crenarchaeol were the major core lipids. Menaquinone MK6 : 0 was the major respiratory quinone. Both isolates gained energy by oxidizing ammonia (NH3) to nitrite (NO2-) and used bicarbonate as a carbon source. Strain D3CT was able use urea as a source of ammonia for energy production and growth. Addition of hydrogen peroxide (H2O2) scavengers (catalase or α-keto acids) was required to sustain growth. Optimal growth occurred between 30 and 32 °C, pH 7.1 and 7.3 and between 34 and 37‰ salinity. The cellular metal abundance ranking of both strains was Fe>Zn>Cu>Mn>Co. The genomes of strains NF5T and D3CT have a DNA G+C content of 33.4 and 33.8 mol%, respectively. Phylogenetic analyses of 16S rRNA gene sequences revealed that both strains are affiliated with the class Nitrososphaeria, sharing ~85 % 16S rRNA gene sequence identity with Nitrososphaera viennensis EN76T. The two isolates are separated by phenotypic and genotypic characteristics and are assigned to distinct species within the genus Nitrosopumilus gen. nov. according to average nucleotide identity thresholds of their closed genomes. Isolates NF5T (=JCM 32270T =NCIMB 15114T) and D3CT (=JCM 32271T =DSM 106147T =NCIMB 15115T) are type strains of the species Nitrosopumilusadriaticus sp. nov. and Nitrosopumiluspiranensis sp. nov., respectively.},
}
@article {pmid30936420,
year = {2019},
author = {Straka, LL and Meinhardt, KA and Bollmann, A and Stahl, DA and Winkler, MH},
title = {Affinity informs environmental cooperation between ammonia-oxidizing archaea (AOA) and anaerobic ammonia-oxidizing (Anammox) bacteria.},
journal = {The ISME journal},
volume = {13},
number = {8},
pages = {1997-2004},
doi = {10.1038/s41396-019-0408-x},
pmid = {30936420},
issn = {1751-7370},
support = {HR0011-17-2-0064//United States Department of Defense | Defense Advanced Research Projects Agency (DARPA)/ ; HR0011-17-2-0064//United States Department of Defense | Defense Advanced Research Projects Agency (DARPA)/ ; HR0011-17-2-0064//United States Department of Defense | Defense Advanced Research Projects Agency (DARPA)/ ; HR0011-17-2-0064//United States Department of Defense | Defense Advanced Research Projects Agency (DARPA)/ ; },
abstract = {Anaerobic ammonia-oxidizing (Anammox) bacteria (AnAOB) rely on nitrite supplied by ammonia-oxidizing bacteria (AOB) and archaea (AOA). Affinities for ammonia and oxygen play a crucial role in AOA/AOB competition and their association with AnAOB. In this work we measured the affinity constants for ammonia and oxygen (half-saturation; km) of two freshwater AOA enrichments, an AOA soil isolate (N. viennensis), and a freshwater AnAOB enrichment. The AOA enrichments had similar kinetics (μmax ≈ 0.36 d-1, km,NH4 ≈ 0.78 µM, and km,O2 ≈ 2.9 µM), whereas N. viennensis had similar km values but lower μmax (0.23 d-1). In agreement with the current paradigm, these AOA strains showed a higher affinity for ammonia (lower km,NH4; 0.34-1.27 µM) than published AOB measurements (>20 µM). The slower growing AnAOB (μmax ≈ 0.16 d-1) had much higher km values (km,NH4 ≈ 132 µM, km,NO2 ≈ 48 µM) and were inhibited by oxygen at low levels (half-oxygen inhibition; ki,O2 ≈ 0.092 µM). The higher affinity of AOA for ammonia relative to AnAOB, suggests AOA/AnAOB cooperation is only possible where AOA do not outcompete AnAOB for ammonia. Using a biofilm model, we show that environments of ammonia/oxygen counter diffusion, such as stratified lakes, favors this cooperation.},
}
@article {pmid30924222,
year = {2019},
author = {Zou, D and Li, Y and Kao, SJ and Liu, H and Li, M},
title = {Genomic adaptation to eutrophication of ammonia-oxidizing archaea in the Pearl River estuary.},
journal = {Environmental microbiology},
volume = {21},
number = {7},
pages = {2320-2332},
doi = {10.1111/1462-2920.14613},
pmid = {30924222},
issn = {1462-2920},
support = {JCYJ20170818091727570//Science and Technology Innovation Committee of Shenzhen/ ; 91851105，31622002//National Natural Science Foundation of China/ ; //State Key Laboratory of Marine Pollution/ ; //Research Grants Council of the Hong Kong Special Administrative Region/ ; },
abstract = {Ammonia-oxidizing archaea (AOA) are ubiquitous in natural ecosystems, and they are responsible for a significant fraction of ammonia oxidation globally. Since the first AOA isolate was established a decade ago, molecular surveys of their environmental distribution [based primarily on amplicon sequencing of the amoA, which codes for the alpha subunit of ammonia monooxygenase (AMO)], show that their habitats are believed to range from marine to terrestrial environments. However, the mechanisms of adaptation underpinning to their habitat expansion remain poorly understood. Here, we report that AOA accounts for almost all of the ammonia oxidizers in the shelf water adjacent to the Pearl River estuary (PRE), with the Nitrosopumilus maritimus SCM1-like (SCM1-like) being the main amoA genotype. Using a metagenomic approach, seven high-quality AOA genomes were reconstructed from the PRE. Phylogenetic analysis indicated that four of these genomes with high completeness were closely affiliated with the Nitrosomatrinus catalina strain SPOT01, which was originally isolated off the coast of California. Genomic comparison revealed that the PRE AOA genomes encoded genes functioning in amino acid synthesis, xenobiotic biodegradation metabolism and transportation of inorganic phosphate and heavy metals. This illustrates the different adaptations of AOA in one of the largest estuaries in China, which is strongly influenced by anthropogenic input. Overall, this study provides additional genomic information about estuarine AOA and highlights the importance of their contribution to nitrification in eutrophic coastal environments.},
}
@article {pmid30923872,
year = {2019},
author = {Wu, RN and Meng, H and Wang, YF and Gu, JD},
title = {Functional dominance and community compositions of ammonia-oxidizing archaea in extremely acidic soils of natural forests.},
journal = {Applied microbiology and biotechnology},
volume = {103},
number = {10},
pages = {4229-4240},
doi = {10.1007/s00253-019-09721-2},
pmid = {30923872},
issn = {1432-0614},
support = {31470562//National Natural Science Foundation of China/ ; },
mesh = {Ammonia/*metabolism ; Archaea/*classification/enzymology/genetics/*metabolism ; *Forests ; Hydrogen-Ion Concentration ; *Microbiota ; Oxidation-Reduction ; Oxidoreductases/analysis/genetics ; RNA, Messenger/analysis/genetics ; Soil/chemistry ; *Soil Microbiology ; },
abstract = {Extremely acidic soils of natural forests in Nanling National Nature Reserve have been previously investigated and revisited in two successive years to reveal the active ammonia oxidizers. Ammonia-oxidizing archaea (AOA) rather than ammonia-oxidizing bacteria (AOB) were found more functionally important in the extremely acidic soils of the natural forests in Nanling National Nature Reserve. The relative abundances of Nitrosotalea, Nitrososphaera sister group, and Nitrososphaera lineages recovered by ammonia monooxygenase subunit A (amoA) transcripts were reassessed and compared to AOA communities formerly detected by genomic DNA. Nitrosotalea, previously found the most abundant AOA, were the second-most-active lineage after Nitrososphaera sister group. Our field study results, therefore, propose the acidophilic AOA, Nitrosotalea, can better reside in extremely acidic soils while they may not contribute to nitrification proportionately according to their abundances or they are less functionally active. In contrast, the functional importance of Nitrososphaera sister group may be previously underestimated and the functional dominance further extends their ecological distribution as little has been reported. Nitrososphaera gargensis-like AOA, the third abundant lineage, were more active in summer. The analyses of AOA community composition and its correlation with environmental parameters support the previous observations of the potential impact of organic matter on AOA composition. Al3+, however, did not show a strong adverse correlation with the abundances of functional AOA unlike in the DNA-based study. The new data further emphasize the functional dominance of AOA in extremely acidic soils, and unveil the relative contributions of AOA lineages to nitrification and their community transitions under the environmental influences.},
}
@article {pmid30918404,
year = {2019},
author = {Chen, SC and Musat, N and Lechtenfeld, OJ and Paschke, H and Schmidt, M and Said, N and Popp, D and Calabrese, F and Stryhanyuk, H and Jaekel, U and Zhu, YG and Joye, SB and Richnow, HH and Widdel, F and Musat, F},
title = {Anaerobic oxidation of ethane by archaea from a marine hydrocarbon seep.},
journal = {Nature},
volume = {568},
number = {7750},
pages = {108-111},
doi = {10.1038/s41586-019-1063-0},
pmid = {30918404},
issn = {1476-4687},
mesh = {Anaerobiosis ; Aquatic Organisms/*metabolism ; Archaea/classification/enzymology/genetics/*metabolism ; Deltaproteobacteria/metabolism ; Ethane/chemistry/*metabolism ; Gases/chemistry/metabolism ; Gulf of Mexico ; Methane/biosynthesis ; Oxidation-Reduction ; Oxidoreductases/genetics/isolation &amp; purification/metabolism ; Phylogeny ; RNA, Ribosomal, 16S/genetics ; Sulfates/metabolism ; Sulfides/metabolism ; },
abstract = {Ethane is the second most abundant component of natural gas in addition to methane, and-similar to methane-is chemically unreactive. The biological consumption of ethane under anoxic conditions was suggested by geochemical profiles at marine hydrocarbon seeps1-3, and through ethane-dependent sulfate reduction in slurries4-7. Nevertheless, the microorganisms and reactions that catalyse this process have to date remained unknown8. Here we describe ethane-oxidizing archaea that were obtained by specific enrichment over ten years, and analyse these archaea using phylogeny-based fluorescence analyses, proteogenomics and metabolite studies. The co-culture, which oxidized ethane completely while reducing sulfate to sulfide, was dominated by an archaeon that we name 'Candidatus Argoarchaeum ethanivorans'; other members were sulfate-reducing Deltaproteobacteria. The genome of Ca. Argoarchaeum contains all of the genes that are necessary for a functional methyl-coenzyme M reductase, and all subunits were detected in protein extracts. Accordingly, ethyl-coenzyme M (ethyl-CoM) was identified as an intermediate by liquid chromatography-tandem mass spectrometry. This indicated that Ca. Argoarchaeum initiates ethane oxidation by ethyl-CoM formation, analogous to the recently described butane activation by 'Candidatus Syntrophoarchaeum'9. Proteogenomics further suggests that oxidation of intermediary acetyl-CoA to CO2 occurs through the oxidative Wood-Ljungdahl pathway. The identification of an archaeon that uses ethane (C2H6) fills a gap in our knowledge of microorganisms that specifically oxidize members of the homologous alkane series (CnH2n+2) without oxygen. Detection of phylogenetic and functional gene markers related to those of Ca. Argoarchaeum at deep-sea gas seeps10-12 suggests that archaea that are able to oxidize ethane through ethyl-CoM are widespread members of the local communities fostered by venting gaseous alkanes around these seeps.},
}
@article {pmid30915060,
year = {2019},
author = {Qiu, X and Yao, Y and Wang, H and Shen, A and Zhang, J},
title = {Halophilic Archaea Mediate the Formation of Proto-Dolomite in Solutions With Various Sulfate Concentrations and Salinities.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {480},
doi = {10.3389/fmicb.2019.00480},
pmid = {30915060},
issn = {1664-302X},
abstract = {In the past several decades, sulfate concentration and salinity have been considered to be the two essential hydrochemical factors in the formation of dolomite, yet arguments against this hypothesis have existed simultaneously. To clarify the effects of sulfate concentration and salinity in the mineralization of dolomite, we conducted experiments on dolomite precipitation mediated by a halophilic archaeon, Natrinema sp. J7-1 with various sulfate concentrations and salinities. This strain was cultured in a series of modified growth media (MGM) with salinities of 140, 200, and 280‰. Cells in the post-log phase were harvested and used to mediate the formation of dolomite in solutions with various sulfate concentrations of 0, 3, 29.8, and 100 mM and salinities of 140, 200, and 280‰. X-ray diffraction (XRD) spectra showed that proto-dolomite, monohydrocalcite, and aragonite formed in samples with cells, yet only aragonite was detected in samples without cells. Proto-dolomite was found in all biotic samples, regardless of the variation in salinity and sulfate concentration. Moreover, the relative abundances of proto-dolomite in the precipitates were positively correlated with the salinities of the media but were uncorrelated with the sulfate concentrations of the solutions. Scanning electronic microscopy (SEM) and energy dispersive spectroscopy (EDS) results showed that all the proto-dolomites were sphere or sphere aggregates with a mole ratio of Mg/Ca close to 1.0. No obvious variations in morphology and Mg/Ca were found among samples with various sulfate concentrations or salinities. This work reveals that a variation of sulfate concentration in solution (from 0 to 100 mM) does not affect the formation of dolomite mediated by halophilic archaea, but an increase of salinity (from 140 to 280‰) enhances this process. Our results indicate that under natural conditions, an increase in salinity may be more significant than the decrease of sulfates in microbe-mediated dolomite formation.},
}
@article {pmid30910020,
year = {2019},
author = {Fu, X and Adams, Z and Maupin-Furlow, J},
title = {Assays for ubiquitin-like protein ligation and proteasome function in archaea.},
journal = {Methods in enzymology},
volume = {619},
number = {},
pages = {161-178},
doi = {10.1016/bs.mie.2018.12.036},
pmid = {30910020},
issn = {1557-7988},
abstract = {Ubiquitin-like protein (Ubl) ligation is common to diverse archaea and targets many cellular pathways, including those associated with sulfur mobilization, and also tags proteins as substrates for degradation by the proteasome. Here we highlight protocols to assay proteasome function and Ubl ligation in archaea. A chase assay is described to monitor the impact of proteasome function on the stability of Ubl-modified proteins in the cell. A method to reconstitute Ubl ligation using a purified E1-like enzyme (UbaA), Ubl (SAMP2), methionine sulfoxide reductase A (MsrA), and cell lysate of an ΔmsrA ΔubaA Δsamp1-3 mutant is also described. MsrA is found to have the surprising ability to stimulate the formation of Ubl bonds. Haloferax volcanii, a halophilic archaeon originally isolated from the Dead Sea, serves as the model organism for these protocols.},
}
@article {pmid30886840,
year = {2019},
author = {Sogodogo, E and Fellag, M and Loukil, A and Nkamga, VD and Michel, J and Dessi, P and Fournier, PE and Drancourt, M},
title = {Nine Cases of Methanogenic Archaea in Refractory Sinusitis, an Emerging Clinical Entity.},
journal = {Frontiers in public health},
volume = {7},
number = {},
pages = {38},
doi = {10.3389/fpubh.2019.00038},
pmid = {30886840},
issn = {2296-2565},
abstract = {The authors report the cases of 9 patients eventually diagnosed with methanogenic archaea refractory or recalcitrant chronic rhinosinusitis, a condition known to involve various anaerobic bacteria but in which the role of methanogenic archaea is unknown. The authors retrospectively searched these microorganisms by PCR in surgically-collected sinusal pus specimens from patients diagnosed with refractory sinusitis, defined by the persistance of sinus inflammation and related-symptoms for more than 12 weeks despite appropriate treatment. Of the 116 tested sinus surgical specimens, 12 (10.3%) from 9 patients (six females, three males; aged 20-71 years) were PCR-positive. These specimens were further investigated by fluorescence in-situ hybridization, PCR amplicon-sequencing and culture. Methanobrevibacter smithii was documented in four patients and Methanobrevibacter oralis in another four, one of whom was also culture-positive. They were associated with a mixed flora including Gram-positive and Gram-negative bacteria. In the latter patient, &quot;Methanobrevibacter massiliense&quot; was the sole microorganism detected. These results highlight methanogenic archaea as being part of a mixed anaerobic flora involved in refractory sinusitis, and suggest that the treatment of this condition should include an antibiotic active against methanogens, notably a nitroimidazole derivative.},
}
@article {pmid30884174,
year = {2019},
author = {Braun, F and Thomalla, L and van der Does, C and Quax, TEF and Allers, T and Kaever, V and Albers, SV},
title = {Cyclic nucleotides in archaea: Cyclic di-AMP in the archaeon Haloferax volcanii and its putative role.},
journal = {MicrobiologyOpen},
volume = {},
number = {},
pages = {e829},
doi = {10.1002/mbo3.829},
pmid = {30884174},
issn = {2045-8827},
support = {311523//H2020 European Research Council/ ; },
abstract = {The role of cyclic nucleotides as second messengers for intracellular signal transduction has been well described in bacteria. One recently discovered bacterial second messenger is cyclic di-adenylate monophosphate (c-di-AMP), which has been demonstrated to be essential in bacteria. Compared to bacteria, significantly less is known about second messengers in archaea. This study presents the first evidence of in vivo presence of c-di-AMP in an archaeon. The model organism Haloferax volcanii was demonstrated to produce c-di-AMP. Its genome encodes one diadenylate cyclase (DacZ) which was shown to produce c-di-AMP in vitro. Similar to bacteria, the dacZ gene is essential and homologous overexpression of DacZ leads to cell death, suggesting the need for tight regulation of c-di-AMP levels. Such tight regulation often indicates the control of important regulatory processes. A central target of c-di-AMP signaling in bacteria is cellular osmohomeostasis. The results presented here suggest a comparable function in H. volcanii. A strain with decreased c-di-AMP levels exhibited an increased cell area in hypo-salt medium, implying impaired osmoregulation. In summary, this study expands the field of research on c-di-AMP and its physiological function to archaea and indicates that osmoregulation is likely to be a common function of c-di-AMP in bacteria and archaea.},
}
@article {pmid30859290,
year = {2019},
author = {Du, Y and Shu, K and Guo, X and Pengjin, Z},
title = {Moderate Grazing Promotes Grassland Nitrous Oxide Emission by Increasing Ammonia-Oxidizing Archaea Abundance on the Tibetan Plateau.},
journal = {Current microbiology},
volume = {76},
number = {5},
pages = {620-625},
doi = {10.1007/s00284-019-01668-x},
pmid = {30859290},
issn = {1432-0991},
support = {31770532//National Natural Science Foundation of China/ ; },
mesh = {Ammonia/*metabolism ; Animals ; Archaea/*metabolism ; Fertilizers/analysis ; *Grassland ; *Herbivory ; Nitrous Oxide/*analysis ; Oxidation-Reduction ; Sheep ; Soil ; Tibet ; },
abstract = {Grasslands are suffering from long-term overgrazing because of the population inflation. Furthermore, nitrous oxide (N2O) is a major greenhouse gas that also depletes stratospheric ozone. However, the emission rate of grassland N2O and underlying mechanisms remained unclear under different grazing intensities. We conducted a field manipulation under four grazing intensities to compare its N2O fluxes and main affected factors. It was indicated that alpine meadow N2O emission rates increased from 39.7 ± 3.1 to 47.8 ± 2.3 μg m-2 h-1 (p < 0.05), then decreased to 43.4 ± 4.1 and 32.9 ± 1.4 μg m-2 h-1 with grazing intensity increasing from 4 to 8, 12 and 16 sheep ha-1, respectively. Multiple-stepwise regression analysis indicated that the predominant affected soil factors were separately TN and BD, pH and BD, also pH and BD, SOC and BD. Simple linear regression models revealed that ammonia-oxidizing archaea (AOA) contributed much to N2O emission (R2 = 0.77). Additionally, the R2 coefficient of linear regression was 0.87 between nosZ genes and N2O emission rates in alpine meadow. Much attention should be paid to protecting alpine meadow from degradation to mitigate N2O emission source on the Tibetan Plateau.},
}
@article {pmid30837306,
year = {2019},
author = {He, D and Piergentili, C and Ross, J and Tarrant, E and Tuck, LR and Mackay, CL and McIver, Z and Waldron, KJ and Clarke, DJ and Marles-Wright, J},
title = {Conservation of the structural and functional architecture of encapsulated ferritins in bacteria and archaea.},
journal = {The Biochemical journal},
volume = {476},
number = {6},
pages = {975-989},
doi = {10.1042/BCJ20180922},
pmid = {30837306},
issn = {1470-8728},
abstract = {Ferritins are a large family of intracellular proteins that protect the cell from oxidative stress by catalytically converting Fe(II) into less toxic Fe(III) and storing iron minerals within their core. Encapsulated ferritins (EncFtn) are a sub-family of ferritin-like proteins, which are widely distributed in all bacterial and archaeal phyla. The recently characterized Rhodospirillum rubrum EncFtn displays an unusual structure when compared with classical ferritins, with an open decameric structure that is enzymatically active, but unable to store iron. This EncFtn must be associated with an encapsulin nanocage in order to act as an iron store. Given the wide distribution of the EncFtn family in organisms with diverse environmental niches, a question arises as to whether this unusual structure is conserved across the family. Here, we characterize EncFtn proteins from the halophile Haliangium ochraceum and the thermophile Pyrococcus furiosus, which show the conserved annular pentamer of dimers topology. Key structural differences are apparent between the homologues, particularly in the centre of the ring and the secondary metal-binding site, which is not conserved across the homologues. Solution and native mass spectrometry analyses highlight that the stability of the protein quaternary structure differs between EncFtn proteins from different species. The ferroxidase activity of EncFtn proteins was confirmed, and we show that while the quaternary structure around the ferroxidase centre is distinct from classical ferritins, the ferroxidase activity is still inhibited by Zn(II). Our results highlight the common structural organization and activity of EncFtn proteins, despite diverse host environments and contexts within encapsulins.},
}
@article {pmid30833729,
year = {2019},
author = {Borrel, G and Adam, PS and McKay, LJ and Chen, LX and Sierra-García, IN and Sieber, CMK and Letourneur, Q and Ghozlane, A and Andersen, GL and Li, WJ and Hallam, SJ and Muyzer, G and de Oliveira, VM and Inskeep, WP and Banfield, JF and Gribaldo, S},
title = {Wide diversity of methane and short-chain alkane metabolisms in uncultured archaea.},
journal = {Nature microbiology},
volume = {4},
number = {4},
pages = {603-613},
doi = {10.1038/s41564-019-0363-3},
pmid = {30833729},
issn = {2058-5276},
mesh = {Alkanes/*chemistry/metabolism ; Archaea/classification/genetics/growth &amp; development/*metabolism ; *Biodiversity ; DNA, Archaeal ; Metagenome ; Methane/chemistry/*metabolism ; Oxidation-Reduction ; Phylogeny ; },
abstract = {Methanogenesis is an ancient metabolism of key ecological relevance, with direct impact on the evolution of Earth's climate. Recent results suggest that the diversity of methane metabolisms and their derivations have probably been vastly underestimated. Here, by probing thousands of publicly available metagenomes for homologues of methyl-coenzyme M reductase complex (MCR), we have obtained ten metagenome-assembled genomes (MAGs) belonging to potential methanogenic, anaerobic methanotrophic and short-chain alkane-oxidizing archaea. Five of these MAGs represent under-sampled (Verstraetearchaeota, Methanonatronarchaeia, ANME-1 and GoM-Arc1) or previously genomically undescribed (ANME-2c) archaeal lineages. The remaining five MAGs correspond to lineages that are only distantly related to previously known methanogens and span the entire archaeal phylogeny. Comprehensive comparative annotation substantially expands the metabolic diversity and energy conservation systems of MCR-bearing archaea. It also suggests the potential existence of a yet uncharacterized type of methanogenesis linked to short-chain alkane/fatty acid oxidation in a previously undescribed class of archaea ('Candidatus Methanoliparia'). We redefine a common core of marker genes specific to methanogenic, anaerobic methanotrophic and short-chain alkane-oxidizing archaea, and propose a possible scenario for the evolutionary and functional transitions that led to the emergence of such metabolic diversity.},
}
@article {pmid30833728,
year = {2019},
author = {Wang, Y and Wegener, G and Hou, J and Wang, F and Xiao, X},
title = {Expanding anaerobic alkane metabolism in the domain of Archaea.},
journal = {Nature microbiology},
volume = {4},
number = {4},
pages = {595-602},
doi = {10.1038/s41564-019-0364-2},
pmid = {30833728},
issn = {2058-5276},
mesh = {Alkanes/chemistry/*metabolism ; Archaea/chemistry/*classification/genetics/*metabolism ; Archaeal Proteins/genetics/metabolism ; Methane/metabolism ; Phylogeny ; },
abstract = {Methanogenesis and anaerobic methane oxidation through methyl-coenzyme M reductase (MCR) as a key enzyme have been suggested to be basal pathways of archaea1. How widespread MCR-based alkane metabolism is among archaea, where it occurs and how it evolved remain elusive. Here, we performed a global survey of MCR-encoding genomes based on metagenomic data from various environments. Eleven high-quality mcr-containing metagenomic-assembled genomes were obtained belonging to the Archaeoglobi in the Euryarchaeota, Hadesarchaeota and different TACK superphylum archaea, including the Nezhaarchaeota, Korarchaeota and Verstraetearchaeota. Archaeoglobi WYZ-LMO1 and WYZ-LMO3 and Korarchaeota WYZ-LMO9 encode both the (reverse) methanogenesis and the dissimilatory sulfate reduction pathway, suggesting that they have the genomic potential to couple both pathways in individual organisms. The Hadesarchaeota WYZ-LMO4-6 and Archaeoglobi JdFR-42 encode highly divergent MCRs, enzymes that may enable them to thrive on non-methane alkanes. The occurrence of mcr genes in different archaeal phyla indicates that MCR-based alkane metabolism is common in the domain of Archaea.},
}
@article {pmid30810807,
year = {2019},
author = {Lopes-Dos-Santos, RMA and De Troch, M and Bossier, P and Van Stappen, G},
title = {Labelling halophilic Archaea using 13C and 15N stable isotopes: a potential tool to investigate haloarchaea consumption by metazoans.},
journal = {Extremophiles : life under extreme conditions},
volume = {23},
number = {3},
pages = {359-365},
doi = {10.1007/s00792-019-01084-w},
pmid = {30810807},
issn = {1433-4909},
support = {BOF/01N01615//Universiteit Gent, Special Research Fund (BOF)/ ; },
mesh = {Animals ; *Biomass ; Carbon Isotopes/*chemistry ; *Food Chain ; Halobacteriales/*growth &amp; development ; Isotope Labeling/*methods ; Nitrogen Isotopes/*chemistry ; },
abstract = {The use of stable isotope (SI) labelling and tracing of live diets is currently considered one of the most comprehensive tools to detect their uptake and assimilation by aquatic organisms. These techniques are indeed widely used in nutritional studies to follow the fate of specific microbial dietary components, unraveling trophic interactions. Nevertheless, to the current date our understanding of aquatic trophic relationships has yet to include a whole domain of life, the Archaea. The aim of the present research was, therefore, to describe a halophilic Archaea (haloarchaea) labelling procedure, using the SI 13C and 15N, to enable the application of SI tracing in future studies of haloarchaea consumption by aquatic metazoans. To this end, three 13C enriched carbon sources and two 15N enriched nitrogen sources were tested as potential labels to enrich cells of three haloarchaea strains when supplemented to the culture medium. Our overall results indicate 13C-glycerol as the most effective carbon source to achieve an efficient 13C enrichment in haloarchaea cells, with Δδ13C values above 5000‰ in all tested haloarchaea strains. As for 15N enriched nitrogen sources, both (15NH4)2SO4 and 15NH4Cl seem to be readily assimilated, also resulting in efficient 15N enrichment in haloarchaea cells, with Δδ15N values higher than 20,000‰. We believe that the proposed methodology will allow for the use of SI labelled haloarchaea biomass in feeding tests, potentially providing unambiguous confirmation of the assimilation of haloarchaea biomass by aquatic metazoans.},
}
@article {pmid30808005,
year = {2019},
author = {Díaz-Perales, A and Quesada, V and Peinado, JR and Ugalde, AP and Álvarez, J and Suárez, MF and Gomis-Rüth, FX and López-Otín, C},
title = {Withdrawal: Identification and characterization of human archaemetzincin-1 and -2, two novel members of a family of metalloproteases widely distributed in Archaea.},
journal = {The Journal of biological chemistry},
volume = {294},
number = {4},
pages = {1434},
doi = {10.1074/jbc.W118.007328},
pmid = {30808005},
issn = {1083-351X},
}
@article {pmid30806656,
year = {2019},
author = {Rissanen, AJ and Peura, S and Mpamah, PA and Taipale, S and Tiirola, M and Biasi, C and Mäki, A and Nykänen, H},
title = {Vertical stratification of bacteria and archaea in sediments of a small boreal humic lake.},
journal = {FEMS microbiology letters},
volume = {366},
number = {5},
pages = {},
doi = {10.1093/femsle/fnz044},
pmid = {30806656},
issn = {1574-6968},
abstract = {Although sediments of small boreal humic lakes are important carbon stores and greenhouse gas sources, the composition and structuring mechanisms of their microbial communities have remained understudied. We analyzed the vertical profiles of microbial biomass indicators (PLFAs, DNA and RNA) and the bacterial and archaeal community composition (sequencing of 16S rRNA gene amplicons and qPCR of mcrA) in sediment cores collected from a typical small boreal lake. While microbial biomass decreased with sediment depth, viable microbes (RNA and PLFA) were present all through the profiles. The vertical stratification patterns of the bacterial and archaeal communities resembled those in marine sediments with well-characterized groups (e.g. Methanomicrobia, Proteobacteria, Cyanobacteria, Bacteroidetes) dominating in the surface sediment and being replaced by poorly-known groups (e.g. Bathyarchaeota, Aminicenantes and Caldiserica) in the deeper layers. The results also suggested that, similar to marine systems, the deep bacterial and archaeal communities were predominantly assembled by selective survival of taxa able to persist in the low energy conditions. Methanotrophs were rare, further corroborating the role of these methanogen-rich sediments as important methane emitters. Based on their taxonomy, the deep-dwelling groups were putatively organo-heterotrophic, organo-autotrophic and/or acetogenic and thus may contribute to changes in the lake sediment carbon storage.},
}
@article {pmid30796982,
year = {2019},
author = {Barnett, DJM and Mommers, M and Penders, J and Arts, ICW and Thijs, C},
title = {Intestinal archaea inversely associated with childhood asthma.},
journal = {The Journal of allergy and clinical immunology},
volume = {143},
number = {6},
pages = {2305-2307},
doi = {10.1016/j.jaci.2019.02.009},
pmid = {30796982},
issn = {1097-6825},
}
@article {pmid30796347,
year = {2019},
author = {Wang, L and Li, K and Sheng, R and Li, Z and Wei, W},
title = {Remarkable N2O emissions by draining fallow paddy soil and close link to the ammonium-oxidizing archaea communities.},
journal = {Scientific reports},
volume = {9},
number = {1},
pages = {2550},
doi = {10.1038/s41598-019-39465-y},
pmid = {30796347},
issn = {2045-2322},
support = {2017M622386//China Postdoctoral Science Foundation/ ; 2017M622386//China Postdoctoral Science Foundation/ ; 41807043//National Natural Science Foundation of China (National Science Foundation of China)/ ; 41807043,41330856//National Natural Science Foundation of China (National Science Foundation of China)/ ; },
abstract = {Fallow paddies experience natural flooding and draining water status due to rainfall and evaporation, which could induce considerable nitrous oxide (N2O) emissions and need to be studied specially. In this study, intact soil columns were collected from a fallow paddy field and the flooding-draining process was simulated in a microcosm experiment. The results showed that both N2O concentrations in the soil and N2O emission rates were negligible during flooding period, which were greatly elevated by draining the fallow paddy soil. The remarkable N2O concentrations in the soil and N2O emission/h during draining both had significant relationships with the Arch-amoA gene (P < 0.01) but not the Bac-amoA, narG, nirK, nirS, and nosZ genes, indicating that the ammonium-oxidizing archaea (AOA) might be the important players in soil N2O net production and emissions after draining. Moreover, we observed that N2O concentrations in the upper soil layers (0-10 cm) were not significantly different from that in the 10-20 cm layer under draining condition (P > 0.05). However, the number of AOA and the nitrification substrate (NH4+-N) in the 0-10 cm layer were significantly higher than in the 10-20 cm layer (P < 0.01), indicating N2O production in the 0-10 cm layer might be higher than the measured concentration and would contribute considerably to N2O emissions as shorter distance of gas diffusion to the soil surface.},
}
@article {pmid30790413,
year = {2019},
author = {Wang, Y and Feng, X and Natarajan, VP and Xiao, X and Wang, F},
title = {Diverse anaerobic methane- and multi-carbon alkane-metabolizing archaea coexist and show activity in Guaymas Basin hydrothermal sediment.},
journal = {Environmental microbiology},
volume = {21},
number = {4},
pages = {1344-1355},
doi = {10.1111/1462-2920.14568},
pmid = {30790413},
issn = {1462-2920},
support = {2018T110390//China Postdoctoral Science Foundation Grant/ ; 41525011//National Natural Science Foundation of China/ ; 91428308//National Natural Science Foundation of China/ ; 91751205//National Natural Science Foundation of China/ ; 2018YFC0310800//State Key R&amp;D Project of China/ ; 2016YFA0601102//State Key R&amp;D Project of China/ ; 2018T110390//China Postdoctoral Science Foundation/ ; 91428308//Natural Science Foundation of China/ ; 91751205//Natural Science Foundation of China/ ; 41525011//Natural Science Foundation of China/ ; },
abstract = {Anaerobic oxidation of methane greatly contributes to global carbon cycling, yet the anaerobic oxidation of non-methane alkanes by archaea was only recently detected in lab enrichments. The distribution and activity of these archaea in natural environments are not yet reported and understood. Here, a combination of metagenomic and metatranscriptomic approaches was utilized to understand the ecological roles and metabolic potentials of methyl-coenzyme M reductase (MCR)-based alkane oxidizing (MAO) archaea in Guaymas Basin sediments. Diverse MAO archaea, including multi-carbon alkane oxidizer Ca. Syntrophoarchaeum spp., anaerobic methane oxidizing archaea ANME-1 and ANME-2c as well as sulfate-reducing bacteria HotSeep-1 and Seep-SRB2 that potentially involved in MAO processes, coexisted and showed activity in Guaymas Basin sediments. High-quality genomic bins of Ca. Syntrophoarchaeum spp., ANME-1 and ANME-2c were retrieved. They all contain and expressed mcr genes and genes in Wood-Ljungdahl pathway for the complete oxidation from alkane to CO2 in local environment, while Ca. Syntrophoarchaeum spp. also possess beta-oxidation genes for multi-carbon alkane degradation. A global survey of potential multi-carbon alkane metabolism archaea shows that they are usually present in organic rich environments but are not limit to hydrothermal or marine ecosystems. Our study provided new insights into ecological and metabolic potentials of MAO archaea in natural environments.},
}
@article {pmid30783016,
year = {2019},
author = {Maier, LK and Marchfelder, A},
title = {It's all about the T: transcription termination in archaea.},
journal = {Biochemical Society transactions},
volume = {47},
number = {1},
pages = {461-468},
doi = {10.1042/BST20180557},
pmid = {30783016},
issn = {1470-8752},
mesh = {Archaea/*genetics ; Genome, Archaeal ; High-Throughput Nucleotide Sequencing ; Terminator Regions, Genetic ; *Transcription Termination, Genetic ; },
abstract = {One of the most fundamental biological processes driving all life on earth is transcription. The, at first glance, relatively simple cycle is divided into three stages: initiation at the promoter site, elongation throughout the open reading frame, and finally termination and product release at the terminator. In all three processes, motifs of the template DNA and protein factors of the transcription machinery including the multisubunit polymerase itself as well as a broad range of associated transcription factors work together and mutually influence each other. Despite several decades of research, this interplay holds delicate mechanistic and structural details as well as interconnections yet to be explored. One of the surprising characteristics of archaeal biology is the use of eukaryotic-like information processing systems against a backdrop of a bacterial-like genome. Archaeal genomes usually comprise main chromosomes alongside chromosomal plasmids, and the genetic information is encoded in single transcriptional units as well as in multicistronic operons alike their bacterial counterparts. Moreover, archaeal genomes are densely packed and this necessitates a tight regulation of transcription and especially assured termination events in order to prevent read-through into downstream coding regions and the accumulation of antisense transcripts.},
}
@article {pmid30763377,
year = {2019},
author = {Ul-Hasan, S and Bowers, RM and Figueroa-Montiel, A and Licea-Navarro, AF and Beman, JM and Woyke, T and Nobile, CJ},
title = {Community ecology across bacteria, archaea and microbial eukaryotes in the sediment and seawater of coastal Puerto Nuevo, Baja California.},
journal = {PloS one},
volume = {14},
number = {2},
pages = {e0212355},
doi = {10.1371/journal.pone.0212355},
pmid = {30763377},
issn = {1932-6203},
support = {R35 GM124594/GM/NIGMS NIH HHS/United States ; },
abstract = {Microbial communities control numerous biogeochemical processes critical for ecosystem function and health. Most analyses of coastal microbial communities focus on the characterization of bacteria present in either sediment or seawater, with fewer studies characterizing both sediment and seawater together at a given site, and even fewer studies including information about non-bacterial microbial communities. As a result, knowledge about the ecological patterns of microbial biodiversity across domains and habitats in coastal communities is limited-despite the fact that archaea, bacteria, and microbial eukaryotes are present and known to interact in coastal habitats. To better understand microbial biodiversity patterns in coastal ecosystems, we characterized sediment and seawater microbial communities for three sites along the coastline of Puerto Nuevo, Baja California, Mexico using both 16S and 18S rRNA gene amplicon sequencing. We found that sediment hosted approximately 500-fold more operational taxonomic units (OTUs) for bacteria, archaea, and microbial eukaryotes than seawater (p < 0.001). Distinct phyla were found in sediment versus seawater samples. Of the top ten most abundant classes, Cytophagia (bacterial) and Chromadorea (eukaryal) were specific to the sediment environment, whereas Cyanobacteria and Bacteroidia (bacterial) and Chlorophyceae (eukaryal) were specific to the seawater environment. A total of 47 unique genera were observed to comprise the core taxa community across environment types and sites. No archaeal taxa were observed as part of either the abundant or core taxa. No significant differences were observed for sediment community composition across domains or between sites. For seawater, the bacterial and archaeal community composition was statistically different for the Major Outlet site (p < 0.05), the site closest to a residential area, and the eukaryal community composition was statistically different between all sites (p < 0.05). Our findings highlight the distinct patterns and spatial heterogeneity in microbial communities of a coastal region in Baja California, Mexico.},
}
@article {pmid30760902,
year = {2019},
author = {Flemming, HC and Wuertz, S},
title = {Bacteria and archaea on Earth and their abundance in biofilms.},
journal = {Nature reviews. Microbiology},
volume = {17},
number = {4},
pages = {247-260},
doi = {10.1038/s41579-019-0158-9},
pmid = {30760902},
issn = {1740-1534},
abstract = {Biofilms are a form of collective life with emergent properties that confer many advantages on their inhabitants, and they represent a much higher level of organization than single cells do. However, to date, no global analysis on biofilm abundance exists. We offer a critical discussion of the definition of biofilms and compile current estimates of global cell numbers in major microbial habitats, mindful of the associated uncertainty. Most bacteria and archaea on Earth (1.2 × 1030 cells) exist in the 'big five' habitats: deep oceanic subsurface (4 × 1029), upper oceanic sediment (5 × 1028), deep continental subsurface (3 × 1029), soil (3 × 1029) and oceans (1 × 1029). The remaining habitats, including groundwater, the atmosphere, the ocean surface microlayer, humans, animals and the phyllosphere, account for fewer cells by orders of magnitude. Biofilms dominate in all habitats on the surface of the Earth, except in the oceans, accounting for ~80% of bacterial and archaeal cells. In the deep subsurface, however, they cannot always be distinguished from single sessile cells; we estimate that 20-80% of cells in the subsurface exist as biofilms. Hence, overall, 40-80% of cells on Earth reside in biofilms. We conclude that biofilms drive all biogeochemical processes and represent the main way of active bacterial and archaeal life.},
}
@article {pmid30742498,
year = {2019},
author = {Serrano, P and Alawi, M and de Vera, JP and Wagner, D},
title = {Response of Methanogenic Archaea from Siberian Permafrost and Non-permafrost Environments to Simulated Mars-like Desiccation and the Presence of Perchlorate.},
journal = {Astrobiology},
volume = {19},
number = {2},
pages = {197-208},
doi = {10.1089/ast.2018.1877},
pmid = {30742498},
issn = {1557-8070},
abstract = {Numerous preflight investigations were necessary prior to the exposure experiment BIOMEX on the International Space Station to test the basic potential of selected microorganisms to resist or even to be active under Mars-like conditions. In this study, methanogenic archaea, which are anaerobic chemolithotrophic microorganisms whose lifestyle would allow metabolism under the conditions on early and recent Mars, were analyzed. Some strains from Siberian permafrost environments have shown a particular resistance. In this investigation, we analyzed the response of three permafrost strains (Methanosarcina soligelidi SMA-21, Candidatus Methanosarcina SMA-17, Candidatus Methanobacterium SMA-27) and two related strains from non-permafrost environments (Methanosarcina mazei, Methanosarcina barkeri) to desiccation conditions (-80°C for 315 days, martian regolith analog simulants S-MRS and P-MRS, a 128-day period of simulated Mars-like atmosphere). Exposure of the different methanogenic strains to increasing concentrations of magnesium perchlorate allowed for the study of their metabolic shutdown in a Mars-relevant perchlorate environment. Survival and metabolic recovery were analyzed by quantitative PCR, gas chromatography, and a new DNA-extraction method from viable cells embedded in S-MRS and P-MRS. All strains survived the two Mars-like desiccating scenarios and recovered to different extents. The permafrost strain SMA-27 showed an increased methanogenic activity by at least 10-fold after deep-freezing conditions. The methanogenic rates of all strains did not decrease significantly after 128 days S-MRS exposure, except for SMA-27, which decreased 10-fold. The activity of strains SMA-17 and SMA-27 decreased after 16 and 60 days P-MRS exposure. Non-permafrost strains showed constant survival and methane production when exposed to both desiccating scenarios. All strains showed unaltered methane production when exposed to the perchlorate concentration reported at the Phoenix landing site (2.4 mM) or even higher concentrations. We conclude that methanogens from (non-)permafrost environments are suitable candidates for potential life in the martian subsurface and therefore are worthy of study after space exposure experiments that approach Mars-like surface conditions.},
}
@article {pmid30733943,
year = {2019},
author = {Isupov, MN and Boyko, KM and Sutter, JM and James, P and Sayer, C and Schmidt, M and Schönheit, P and Nikolaeva, AY and Stekhanova, TN and Mardanov, AV and Ravin, NV and Bezsudnova, EY and Popov, VO and Littlechild, JA},
title = {Thermostable Branched-Chain Amino Acid Transaminases From the Archaea Geoglobus acetivorans and Archaeoglobus fulgidus: Biochemical and Structural Characterization.},
journal = {Frontiers in bioengineering and biotechnology},
volume = {7},
number = {},
pages = {7},
doi = {10.3389/fbioe.2019.00007},
pmid = {30733943},
issn = {2296-4185},
abstract = {Two new thermophilic branched chain amino acid transaminases have been identified within the genomes of different hyper-thermophilic archaea, Geoglobus acetivorans, and Archaeoglobus fulgidus. These enzymes belong to the class IV of transaminases as defined by their structural fold. The enzymes have been cloned and over-expressed in Escherichia coli and the recombinant enzymes have been characterized both biochemically and structurally. Both enzymes showed high thermostability with optimal temperature for activity at 80 and 85°C, respectively. They retain good activity after exposure to 50% of the organic solvents, ethanol, methanol, DMSO and acetonitrile. The enzymes show a low activity to (R)-methylbenzylamine but no activity to (S)-methylbenzylamine. Both enzymes have been crystallized and their structures solved in the internal aldimine form, to 1.9 Å resolution for the Geoglobus enzyme and 2.0 Å for the Archaeoglobus enzyme. Also the Geoglobus enzyme structure has been determined in complex with the amino acceptor α-ketoglutarate and the Archaeoglobus enzyme in complex with the inhibitor gabaculine. These two complexes have helped to determine the conformation of the enzymes during enzymatic turnover and have increased understanding of their substrate specificity. A comparison has been made with another (R) selective class IV transaminase from the fungus Nectria haematococca which was previously studied in complex with gabaculine. The subtle structural differences between these enzymes has provided insight regarding their different substrate specificities.},
}
@article {pmid30714894,
year = {2019},
author = {Portugal, R and Shao, N and Whitman, WB and Allen, KD and White, RH},
title = {Identification and biosynthesis of 2-(1H-imidazol-5-yl) ethan-1-ol (histaminol) in methanogenic archaea.},
journal = {Microbiology (Reading, England)},
volume = {165},
number = {4},
pages = {455-462},
doi = {10.1099/mic.0.000779},
pmid = {30714894},
issn = {1465-2080},
abstract = {Histaminol is a relatively rare metabolite most commonly resulting from histidine metabolism. Here we describe histaminol production and secretion into the culture broth by the methanogen Methanococcus maripaludis S2 as well as a number of other methanogens. This work is the first identification of this compound as a natural product in methanogens. Its biosynthesis from histidine was confirmed by the incorporation of 2H3-histidine into histaminol by growing cells of M. maripaludis S2. Possible functions of this molecule could be cell signaling as observed with histamine in eukaryotes or uptake of metal ions.},
}
@article {pmid30709414,
year = {2019},
author = {Jiao, S and Xu, Y and Zhang, J and Lu, Y},
title = {Environmental filtering drives distinct continental atlases of soil archaea between dryland and wetland agricultural ecosystems.},
journal = {Microbiome},
volume = {7},
number = {1},
pages = {15},
doi = {10.1186/s40168-019-0630-9},
pmid = {30709414},
issn = {2049-2618},
mesh = {Agriculture ; Archaea/*classification/genetics ; Crops, Agricultural/*microbiology ; Environment ; Oryza/*microbiology ; RNA, Ribosomal, 16S/genetics ; Soil/chemistry ; *Soil Microbiology ; Wetlands ; Zea mays/*microbiology ; },
abstract = {BACKGROUND: Understanding the spatial distributions and ecological diversity of soil archaeal communities in agricultural ecosystems is crucial for improvements in crop productivity. Here, we conducted a comprehensive, continental-scale survey of soil archaeal communities in adjacent pairs of maize (dryland) and rice (wetland) fields in eastern China.<br><br>RESULTS: We revealed the consequential roles of environmental filtering in driving archaeal community assembly for both maize and rice fields. Rice fields, abundant with Euryarchaeota, had higher archaeal diversity and steeper distance-decay slopes than maize fields dominated by Thaumarchaeota. Dominant soil archaea showed distinct continental atlases and niche differentiation between dryland and wetland habitats, where they were associated with soil pH and mean annual temperature, respectively. After identifying their environmental preferences, we grouped the dominant archaeal taxa into different ecological clusters and determined the unique co-occurrence patterns within each cluster. Using this empirical dataset, we built a continental atlas of soil archaeal communities to provide reliable estimates of their spatial distributions in agricultural ecosystems.<br><br>CONCLUSIONS: Environmental filtering plays a crucial role in driving the distinct continental atlases of dominant soil archaeal communities between dryland and wetland, with contrasting strategies of archaeal-driven nutrient cycling within these two agricultural ecosystems. These findings improve our ability to predict how soil archaeal communities respond to environmental changes and to manage soil archaeal communities for provisioning of agricultural ecosystem services.},
}
@article {pmid30707467,
year = {2019},
author = {Reinhardt, A and Johnsen, U and Schönheit, P},
title = {l-Rhamnose catabolism in archaea.},
journal = {Molecular microbiology},
volume = {111},
number = {4},
pages = {1093-1108},
doi = {10.1111/mmi.14213},
pmid = {30707467},
issn = {1365-2958},
support = {SCHO 316/12-1//Deutsche Forschungsgemeinschaft/ ; },
abstract = {The halophilic archaeon Haloferax volcanii utilizes l-rhamnose as a sole carbon and energy source. It is shown that l-rhamnose is taken up by an ABC transporter and is oxidatively degraded to pyruvate and l-lactate via the diketo-hydrolase pathway. The genes involved in l-rhamnose uptake and degradation form a l-rhamnose catabolism (rhc) gene cluster. The rhc cluster also contains a gene, rhcR, that encodes the transcriptional regulator RhcR which was characterized as an activator of all rhc genes. 2-keto-3-deoxy-l-rhamnonate, a metabolic intermediate of l-rhamnose degradation, was identified as inducer molecule of RhcR. The essential function of rhc genes for uptake and degradation of l-rhamnose was proven by the respective knockout mutants. Enzymes of the diketo-hydrolase pathway, including l-rhamnose dehydrogenase, l-rhamnonolactonase, l-rhamnonate dehydratase, 2-keto-3-deoxy-l-rhamnonate dehydrogenase and 2,4-diketo-3-deoxy-l-rhamnonate hydrolase, were characterized. Further, genes of the diketo-hydrolase pathway were also identified in the hyperthermophilic crenarchaeota Vulcanisaeta distributa and Sulfolobus solfataricus and selected enzymes were characterized, indicating the presence of the diketo-hydrolase pathway in these archaea. Together, this is the first comprehensive description of l-rhamnose catabolism in the domain of archaea.},
}
@article {pmid30691532,
year = {2019},
author = {Korzhenkov, AA and Toshchakov, SV and Bargiela, R and Gibbard, H and Ferrer, M and Teplyuk, AV and Jones, DL and Kublanov, IV and Golyshin, PN and Golyshina, OV},
title = {Archaea dominate the microbial community in an ecosystem with low-to-moderate temperature and extreme acidity.},
journal = {Microbiome},
volume = {7},
number = {1},
pages = {11},
doi = {10.1186/s40168-019-0623-8},
pmid = {30691532},
issn = {2049-2618},
support = {BB/M029085/1//Biotechnology and Biological Sciences Research Council/United Kingdom ; },
mesh = {Acids/metabolism ; Archaea/*classification/genetics/*isolation &amp; purification ; Bacteria/classification/genetics/*isolation &amp; purification ; Cold Temperature ; Ecosystem ; Geologic Sediments/*microbiology ; Metagenome/genetics ; Microbiota/physiology ; RNA, Ribosomal, 16S/genetics ; Wales ; },
abstract = {BACKGROUND: The current view suggests that in low-temperature acidic environments, archaea are significantly less abundant than bacteria. Thus, this study of the microbiome of Parys Mountain (Anglesey, UK) sheds light on the generality of this current assumption. Parys Mountain is a historically important copper mine and its acid mine drainage (AMD) water streams are characterised by constant moderate temperatures (8-18 °C), extremely low pH (1.7) and high concentrations of soluble iron and other metal cations.<br><br>RESULTS: Metagenomic and SSU rRNA amplicon sequencing of DNA from Parys Mountain revealed a significant proportion of archaea affiliated with Euryarchaeota, which accounted for ca. 67% of the community. Within this phylum, potentially new clades of Thermoplasmata were overrepresented (58%), with the most predominant group being &quot;E-plasma&quot;, alongside low-abundant Cuniculiplasmataceae, 'Ca. Micrarchaeota' and 'Terrestrial Miscellaneous Euryarchaeal Group' (TMEG) archaea, which were phylogenetically close to Methanomassilicoccales and clustered with counterparts from acidic/moderately acidic settings. In the sediment, archaea and Thermoplasmata contributed the highest numbers in V3-V4 amplicon reads, in contrast with the water body community, where Proteobacteria, Nitrospirae, Acidobacteria and Actinobacteria outnumbered archaea. Cultivation efforts revealed the abundance of archaeal sequences closely related to Cuniculiplasma divulgatum in an enrichment culture established from the filterable fraction of the water sample. Enrichment cultures with unfiltered samples showed the presence of Ferrimicrobium acidiphilum, C. divulgatum, 'Ca. Mancarchaeum acidiphilum Mia14', 'Ca. Micrarchaeota'-related and diverse minor (< 2%) bacterial metagenomic reads.<br><br>CONCLUSION: Contrary to expectation, our study showed a high abundance of archaea in this extremely acidic mine-impacted environment. Further, archaeal populations were dominated by one particular group, suggesting that they are functionally important. The prevalence of archaea over bacteria in these microbiomes and their spatial distribution patterns represents a novel and important advance in our understanding of acidophile ecology. We also demonstrated a procedure for the specific enrichment of cell wall-deficient members of the archaeal component of this community, although the large fraction of archaeal taxa remained unculturable. Lastly, we identified a separate clustering of globally occurring acidophilic members of TMEG that collectively belong to a distinct order within Thermoplasmata with yet unclear functional roles in the ecosystem.},
}
@article {pmid30664670,
year = {2019},
author = {Evans, PN and Boyd, JA and Leu, AO and Woodcroft, BJ and Parks, DH and Hugenholtz, P and Tyson, GW},
title = {An evolving view of methane metabolism in the Archaea.},
journal = {Nature reviews. Microbiology},
volume = {17},
number = {4},
pages = {219-232},
doi = {10.1038/s41579-018-0136-7},
pmid = {30664670},
issn = {1740-1534},
abstract = {Methane is a key compound in the global carbon cycle that influences both nutrient cycling and the Earth's climate. A limited number of microorganisms control the flux of biologically generated methane, including methane-metabolizing archaea that either produce or consume methane. Methanogenic and methanotrophic archaea belonging to the phylum Euryarchaeota share a genetically similar, interrelated pathway for methane metabolism. The key enzyme in this pathway, the methyl-coenzyme M reductase (Mcr) complex, catalyses the last step in methanogenesis and the first step in methanotrophy. The discovery of mcr and divergent mcr-like genes in new euryarchaeotal lineages and novel archaeal phyla challenges long-held views of the evolutionary origin of this metabolism within the Euryarchaeota. Divergent mcr-like genes have recently been shown to oxidize short-chain alkanes, indicating that these complexes have evolved to metabolize substrates other than methane. In this Review, we examine the diversity, metabolism and evolutionary history of mcr-containing archaea in light of these recent discoveries.},
}
@article {pmid30655519,
year = {2019},
author = {Díez-Villaseñor, C and Rodriguez-Valera, F},
title = {CRISPR analysis suggests that small circular single-stranded DNA smacoviruses infect Archaea instead of humans.},
journal = {Nature communications},
volume = {10},
number = {1},
pages = {294},
doi = {10.1038/s41467-018-08167-w},
pmid = {30655519},
issn = {2041-1723},
mesh = {Archaea/*genetics/virology ; CRISPR-Cas Systems/genetics ; Clustered Regularly Interspaced Short Palindromic Repeats/genetics ; DNA Viruses/genetics/isolation &amp; purification/*pathogenicity ; DNA, Single-Stranded/*genetics ; Feces/microbiology ; Gastrointestinal Microbiome/*genetics ; Host-Pathogen Interactions/*genetics ; Humans ; Phylogeny ; },
abstract = {Smacoviridae is a family of small (~2.5 Kb) CRESS-DNA (Circular Rep Encoding Single-Stranded (ss) DNA) viruses. These viruses have been found in faeces, were thought to infect eukaryotes and are suspected to cause gastrointestinal disease in humans. CRISPR-Cas systems are adaptive immune systems in prokaryotes, wherein snippets of genomes from invaders are stored as spacers that are interspersed between a repeated CRISPR sequence. Here we report several spacer sequences in the faecal archaeon Candidatus Methanomassiliicoccus intestinalis matching smacoviruses, implicating the archaeon as a firm candidate for a host. This finding may be relevant to understanding the potential origin of smacovirus-associated human diseases. Our results support that CRESS-DNA viruses can infect non-eukaryotes, which would mean that smacoviruses are the viruses with the smallest genomes to infect prokaryotes known to date. A probable target strand bias suggests that, in addition to double-stranded DNA, the CRISPR-Cas system can target ssDNA.},
}
@article {pmid30640434,
year = {2019},
author = {Jeter, VL and Mattes, TA and Beattie, NR and Escalante-Semerena, JC},
title = {A New Class of Phosphoribosyltransferases Involved in Cobamide Biosynthesis Is Found in Methanogenic Archaea and Cyanobacteria.},
journal = {Biochemistry},
volume = {58},
number = {7},
pages = {951-964},
doi = {10.1021/acs.biochem.8b01253},
pmid = {30640434},
issn = {1520-4995},
support = {R37 GM040313/GM/NIGMS NIH HHS/United States ; },
abstract = {Cobamides are coenzymes used by cells from all domains of life but made de novo by only some bacteria and archaea. The last steps of the cobamide biosynthetic pathway activate the corrin ring and the lower ligand base, condense the activated intermediates, and dephosphorylate the product prior to the release of the biologically active coenzyme. In bacteria, a phosphoribosyltransferase (PRTase) enyzme activates the base into its α-mononucleotide. The enzyme from Salmonella enterica (SeCobT) has been extensively biochemically and structurally characterized. The crystal structure of the putative PRTase from the archaeum Methanocaldococcus jannaschii (MjCobT) is known, but its function has not been validated. Here we report the in vivo and in vitro characterization of MjCobT. In vivo, in vitro, and phylogenetic data reported here show that MjCobT belongs to a new class of NaMN-dependent PRTases. We also show that the Synechococcus sp. WH7803 CobT protein has PRTase activity in vivo. Lastly, results of isothermal titration calorimetry and analytical ultracentrifugation analysis show that the biologically active form of MjCobT is a dimer, not a trimer, as suggested by its crystal structure.},
}
@article {pmid30629179,
year = {2019},
author = {Dombrowski, N and Lee, JH and Williams, TA and Offre, P and Spang, A},
title = {Genomic diversity, lifestyles and evolutionary origins of DPANN archaea.},
journal = {FEMS microbiology letters},
volume = {366},
number = {2},
pages = {},
doi = {10.1093/femsle/fnz008},
pmid = {30629179},
issn = {1574-6968},
abstract = {Archaea-a primary domain of life besides Bacteria-have for a long time been regarded as peculiar organisms that play marginal roles in biogeochemical cycles. However, this picture changed with the discovery of a large diversity of archaea in non-extreme environments enabled by the use of cultivation-independent methods. These approaches have allowed the reconstruction of genomes of uncultivated microorganisms and revealed that archaea are diverse and broadly distributed in the biosphere and seemingly include a large diversity of putative symbiotic organisms, most of which belong to the tentative archaeal superphylum referred to as DPANN. This archaeal group encompasses at least 10 different lineages and includes organisms with extremely small cell and genome sizes and limited metabolic capabilities. Therefore, many members of DPANN may be obligately dependent on symbiotic interactions with other organisms and may even include novel parasites. In this contribution, we review the current knowledge of the gene repertoires and lifestyles of members of this group and discuss their placement in the tree of life, which is the basis for our understanding of the deep microbial roots and the role of symbiosis in the evolution of life on Earth.},
}
@article {pmid30624459,
year = {2019},
author = {Morgado, SM and Vicente, ACP},
title = {Exploring tRNA gene cluster in archaea.},
journal = {Memorias do Instituto Oswaldo Cruz},
volume = {114},
number = {},
pages = {e180348},
doi = {10.1590/0074-02760180348},
pmid = {30624459},
issn = {1678-8060},
mesh = {Archaea/*genetics ; Evolution, Molecular ; Genome, Archaeal/*genetics ; Multigene Family/*genetics ; Phylogeny ; RNA, Archaeal/*genetics ; RNA, Transfer/*genetics ; Sequence Alignment ; },
abstract = {BACKGROUND: Shared traits between prokaryotes and eukaryotes are helpful in the understanding of the tree of life evolution. In bacteria and eukaryotes, it has been shown a particular organisation of tRNA genes as clusters, but this trait has not been explored in the archaea domain.<br><br>OBJECTIVE: Explore the occurrence of tRNA gene clusters in archaea.<br><br>METHODS: In-silico analyses of complete and draft archaeal genomes based on tRNA gene isotype and synteny, tRNA gene cluster content and mobilome elements.<br><br>FINDINGS: We demonstrated the prevalence of tRNA gene clusters in archaea. tRNA gene clusters, composed of archaeal-type tRNAs, were identified in two Archaea class, Halobacteria and Methanobacteria from Euryarchaeota supergroup. Genomic analyses also revealed evidence of the association between tRNA gene clusters to mobile genetic elements and intra-domain horizontal gene transfer.<br><br>MAIN CONCLUSIONS: tRNA gene cluster occurs in the three domains of life, suggesting a role of this type of tRNA gene organisation in the biology of the living organisms.},
}
@article {pmid30606162,
year = {2019},
author = {Xue, F and Nan, X and Li, Y and Pan, X and Guo, Y and Jiang, L and Xiong, B},
title = {Metagenomic insights into effects of thiamine supplementation on ruminal non-methanogen archaea in high-concentrate diets feeding dairy cows.},
journal = {BMC veterinary research},
volume = {15},
number = {1},
pages = {7},
doi = {10.1186/s12917-018-1745-0},
pmid = {30606162},
issn = {1746-6148},
support = {Grant No. 31572435//Project of National Nature Science Foundation of China/ ; 2016YFD0700205//National Key Research and Development Plan/ ; },
mesh = {Animal Feed ; Animals ; Archaea/*drug effects/genetics ; Cattle ; Diet/*veterinary ; *Dietary Supplements ; Eating/drug effects ; Female ; Gastrointestinal Microbiome/drug effects ; Hydrogen-Ion Concentration ; Lactation/drug effects ; Metagenomics ; Rumen/chemistry/*microbiology ; Thiamine/analysis/*pharmacology ; },
abstract = {BACKGROUND: Overfeeding of high-concentrate diet (HC) frequently leads to subacute ruminal acidosis (SARA) in modern dairy cows' production. Thiamine supplementation has been confirmed to attenuate HC induced SARA by increasing ruminal pH and ratio of acetate to propionate, and decreasing rumen lactate, biogenic amines and lipopolysaccharide (LPS). The effects of thiamine supplementation in HC on rumen bacteria and fungi profile had been detected in our previous studies, however, effects of thiamine supplementation in HC on rumen non-methanogen archaea is still unclear. The objective of the present study was therefore to investigate the effects of thiamine supplementation on ruminal archaea, especially non-methanogens in HC induced SARA cows.<br><br>RESULTS: HC feeding significantly decreased dry matter intake, milk production, milk fat content, ruminal pH and the concentrations of thiamine and acetate in rumen fluid compared with control diet (CON) (P < 0.05), while the concentrations of propionate and ammonia-nitrogen (NH3-N) were significantly increased compared with CON (P < 0.05). These changes caused by HC were inversed by thiamine supplementation (P < 0.05). The taxonomy results showed that ruminal archaea ranged from 0.37 to 0.47% of the whole microbiota. Four characterized phyla, a number of Candidatus archaea and almost 660 species were identified in the present study. In which Euryarchaeota occupied the largest proportion of the whole archaea. Furthermore, thiamine supplementation treatment significantly increased the relative abundance of non-methanogens compared with CON and HC treatments. Thaumarchaeota was increased in HC compared with CON. Thiamine supplementation significantly increased Crenarchaeota, Nanoarchaeota and the Candidatus phyla, however decreased Thaumarchaeota compared with HC treatment.<br><br>CONCLUSIONS: HC feeding significantly decreased ruminal pH and increased the content of NH3-N which led to N loss and the increase of the relative abundance of Thaumarchaeota. Thiamine supplementation increased ruminal pH, improved the activity of ammonia utilizing bacteria, and decreased Thaumarchaeota abundance to reduce the ruminal NH3 content and finally reduced N loss. Overall, these findings contributed to the understanding of thiamine's function in dairy cows and provided new strategies to improve dairy cows' health under high-concentrate feeding regime.},
}
@article {pmid30592124,
year = {2019},
author = {Wang, Y and Huang, JM and Cui, GJ and Nunoura, T and Takaki, Y and Li, WL and Li, J and Gao, ZM and Takai, K and Zhang, AQ and Stepanauskas, R},
title = {Genomics insights into ecotype formation of ammonia-oxidizing archaea in the deep ocean.},
journal = {Environmental microbiology},
volume = {21},
number = {2},
pages = {716-729},
doi = {10.1111/1462-2920.14518},
pmid = {30592124},
issn = {1462-2920},
support = {EF-0826924//NSF/ ; OCE-1335810//NSF/ ; OCE-1232982//NSF/ ; 30070015//Japan Society for the Promotion of Science/ ; 2016YFC0302500//Research and Development/ ; XDB06040101//Chinese Academy of Sciences/ ; XDB06010201//Chinese Academy of Sciences/ ; 31460001//National Science Foundation of China/ ; 41476104//National Science Foundation of China/ ; },
abstract = {Various lineages of ammonia-oxidizing archaea (AOA) are present in deep waters, but the mechanisms that determine ecotype formation are obscure. We studied 18 high-quality genomes of the marine group I AOA lineages (alpha, gamma and delta) from the Mariana and Ogasawara trenches. The genomes of alpha AOA resembled each other, while those of gamma and delta lineages were more divergent and had even undergone insertion of some phage genes. The instability of the gamma and delta AOA genomes could be partially due to the loss of DNA polymerase B (polB) and methyladenine DNA glycosylase (tag) genes responsible for the repair of point mutations. The alpha AOA genomes harbour genes encoding a thrombospondin-like outer membrane structure that probably serves as a barrier to gene flow. Moreover, the gamma and alpha AOA lineages rely on vitamin B12 -independent MetE and B12 -dependent MetH, respectively, for methionine synthesis. The delta AOA genome contains genes involved in uptake of sugar and peptide perhaps for heterotrophic lifestyle. Our study provides insights into co-occurrence of cladogenesis and anagenesis in the formation of AOA ecotypes that perform differently in nitrogen and carbon cycling in dark oceans.},
}
@article {pmid30581371,
year = {2018},
author = {Li, J and Liu, R and Tao, Y and Li, G},
title = {Archaea in Wastewater Treatment: Current Research and Emerging Technology.},
journal = {Archaea (Vancouver, B.C.)},
volume = {2018},
number = {},
pages = {6973294},
doi = {10.1155/2018/6973294},
pmid = {30581371},
issn = {1472-3654},
mesh = {Archaea/*growth &amp; development/*metabolism ; Biotechnology/*methods/trends ; Waste Water/*microbiology ; Water Purification/*methods ; },
}
@article {pmid30573104,
year = {2019},
author = {Li, N and Chen, Y and Zhang, Z and Chang, S and Huang, D and Chen, S and Guo, Q and Xie, S and Bing, Y},
title = {Response of ammonia-oxidizing archaea to heavy metal contamination in freshwater sediment.},
journal = {Journal of environmental sciences (China)},
volume = {77},
number = {},
pages = {392-399},
doi = {10.1016/j.jes.2018.09.020},
pmid = {30573104},
issn = {1001-0742},
mesh = {Ammonia/*metabolism ; Archaea/classification/*drug effects/*metabolism ; Biodiversity ; Cluster Analysis ; Fresh Water/*microbiology ; Geologic Sediments/*chemistry ; Metals, Heavy/analysis/*pharmacology ; Oxidation-Reduction ; Phylogeny ; Water Pollutants, Chemical/analysis/*pharmacology ; },
abstract = {It has been well-documented that the distribution of ammonia-oxidizing bacteria (AOB) and archaea (AOA) in soils can be affected by heavy metal contamination, whereas information about the impact of heavy metal on these ammonia-oxidizing microorganisms in freshwater sediment is still lacking. The present study explored the change of sediment ammonia-oxidizing microorganisms in a freshwater reservoir after being accidentally contaminated by industrial discharge containing high levels of metals. Bacterial amoA gene was found to be below the quantitative PCR detection and was not successfully amplified by conventional PCR. The number of archaeal amoA gene in reservoir sediments were 9.62 × 102-1.35 × 107 copies per gram dry sediment. AOA abundance continuously decreased, and AOA richness, diversity and community structure also considerably varied with time. Therefore, heavy metal pollution could have a profound impact on freshwater sediment AOA community. This work could expand our knowledge of the effect of heavy metal contamination on nitrification in natural ecosystems.},
}
@article {pmid30559729,
year = {2018},
author = {Yu, H and Susanti, D and McGlynn, SE and Skennerton, CT and Chourey, K and Iyer, R and Scheller, S and Tavormina, PL and Hettich, RL and Mukhopadhyay, B and Orphan, VJ},
title = {Comparative Genomics and Proteomic Analysis of Assimilatory Sulfate Reduction Pathways in Anaerobic Methanotrophic Archaea.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {2917},
doi = {10.3389/fmicb.2018.02917},
pmid = {30559729},
issn = {1664-302X},
abstract = {Sulfate is the predominant electron acceptor for anaerobic oxidation of methane (AOM) in marine sediments. This process is carried out by a syntrophic consortium of anaerobic methanotrophic archaea (ANME) and sulfate reducing bacteria (SRB) through an energy conservation mechanism that is still poorly understood. It was previously hypothesized that ANME alone could couple methane oxidation to dissimilatory sulfate reduction, but a genetic and biochemical basis for this proposal has not been identified. Using comparative genomic and phylogenetic analyses, we found the genetic capacity in ANME and related methanogenic archaea for sulfate reduction, including sulfate adenylyltransferase, APS kinase, APS/PAPS reductase and two different sulfite reductases. Based on characterized homologs and the lack of associated energy conserving complexes, the sulfate reduction pathways in ANME are likely used for assimilation but not dissimilation of sulfate. Environmental metaproteomic analysis confirmed the expression of 6 proteins in the sulfate assimilation pathway of ANME. The highest expressed proteins related to sulfate assimilation were two sulfite reductases, namely assimilatory-type low-molecular-weight sulfite reductase (alSir) and a divergent group of coenzyme F420-dependent sulfite reductase (Group II Fsr). In methane seep sediment microcosm experiments, however, sulfite and zero-valent sulfur amendments were inhibitory to ANME-2a/2c while growth in their syntrophic SRB partner was not observed. Combined with our genomic and metaproteomic results, the passage of sulfur species by ANME as metabolic intermediates for their SRB partners is unlikely. Instead, our findings point to a possible niche for ANME to assimilate inorganic sulfur compounds more oxidized than sulfide in anoxic marine environments.},
}
@article {pmid30550095,
year = {2018},
author = {Lvov, DK and Sizikova, TE and Lebedev, VN and Borisevich, SV},
title = {[Plasmids of archaea as possible ancestors of DNA-containing viruses].},
journal = {Voprosy virusologii},
volume = {63},
number = {5},
pages = {197-201},
doi = {10.18821/0507-4088-2018-63-5-197-201},
pmid = {30550095},
issn = {2411-2097},
abstract = {Тhе kingdom Archaea, as well as Bacteria, belongs to the overkingdom Prokaryota. Halophilic archaea (Halorubrum lacusprofundi) isolated from Antarctic saline lakes contain plasmids (pR1SE) that code proteins taking part in the formation of membranes of archaea vesicles. The molecular and biological properties of pR1SE and the peculiarity of its interaction with sensitive cells are considered in this article. The role of structural proteins coded by pR1S in the process of formation of vesicle membrane complex is paid special attention. Plasmid-containing archaea vesicles model some properties of viruses. Archaea plasmids can be viewed as possible ancestors of DNA-containing viruses.},
}
@article {pmid30544151,
year = {2019},
author = {Jaffe, AL and Castelle, CJ and Dupont, CL and Banfield, JF},
title = {Lateral Gene Transfer Shapes the Distribution of RuBisCO among Candidate Phyla Radiation Bacteria and DPANN Archaea.},
journal = {Molecular biology and evolution},
volume = {36},
number = {3},
pages = {435-446},
doi = {10.1093/molbev/msy234},
pmid = {30544151},
issn = {1537-1719},
mesh = {Archaea/*genetics ; Bacteria/*genetics ; Bacteriophages/*genetics ; *Gene Transfer, Horizontal ; Metagenomics ; Phosphotransferases (Alcohol Group Acceptor)/genetics ; Phylogeny ; Ribulose-Bisphosphate Carboxylase/*genetics ; },
abstract = {Ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) is considered to be the most abundant enzyme on Earth. Despite this, its full diversity and distribution across the domains of life remain to be determined. Here, we leverage a large set of bacterial, archaeal, and viral genomes recovered from the environment to expand our understanding of existing RuBisCO diversity and the evolutionary processes responsible for its distribution. Specifically, we report a new type of RuBisCO present in Candidate Phyla Radiation (CPR) bacteria that is related to the archaeal Form III enzyme and contains the amino acid residues necessary for carboxylase activity. Genome-level metabolic analyses supported the inference that these RuBisCO function in a CO2-incorporating pathway that consumes nucleotides. Importantly, some Gottesmanbacteria (CPR) also encode a phosphoribulokinase that may augment carbon metabolism through a partial Calvin-Benson-Bassham cycle. Based on the scattered distribution of RuBisCO and its discordant evolutionary history, we conclude that this enzyme has been extensively laterally transferred across the CPR bacteria and DPANN archaea. We also report RuBisCO-like proteins in phage genomes from diverse environments. These sequences cluster with proteins in the Beckwithbacteria (CPR), implicating phage as a possible mechanism of RuBisCO transfer. Finally, we synthesize our metabolic and evolutionary analyses to suggest that lateral gene transfer of RuBisCO may have facilitated major shifts in carbon metabolism in several important bacterial and archaeal lineages.},
}
@article {pmid30530297,
year = {2019},
author = {Wang, S and Zheng, Z and Zou, H and Li, N and Wu, M},
title = {Characterization of the secondary metabolite biosynthetic gene clusters in archaea.},
journal = {Computational biology and chemistry},
volume = {78},
number = {},
pages = {165-169},
doi = {10.1016/j.compbiolchem.2018.11.019},
pmid = {30530297},
issn = {1476-928X},
mesh = {Archaea/*genetics/metabolism ; Bacteriocins/*biosynthesis/chemistry/genetics ; *Multigene Family ; },
abstract = {Secondary metabolites are a range of bioactive compounds yielded by bacteria, fungi and plants, etc. The published archaea genomic data provide the opportunity for efficient identification of secondary metabolite biosynthetic gene clusters (BGCs) by genome mining. However, the study of secondary metabolites in archaea is still rare. By using the antiSMASH, we found two main putative secondary metabolite BGCs, bacteriocin and terpene in 203 Archaea genomes. Compared with the genomes of Euryarchaeota that usually lives in less complexity of environment, the genomes of Crenarchaeota usually contained more abundant bacteriocin. In these archaea genomes, we also found the positive correlation between the abundance of bacteriocin and the abundance of CRISPR spacer, suggesting the bacteriocin might be a crucial component of the innate immune system that defense the microbe living in the common environment. The structure analysis of the bacteriocin gene clusters gave a clue that the assisted genes located at the edge of clusters evolved faster than the core biosynthetic genes. To the best of our knowledge, we are the first to systematically explore the distribution of secondary metabolites in archaea, and the investigation of the relationship between BGC and CRISPR spacer expands our understanding of the evolutionary dynamic of these functional molecules.},
}
@article {pmid30520969,
year = {2018},
author = {Alva, V and Lupas, AN},
title = {Histones Predate the Split Between Bacteria and Archaea.},
journal = {Bioinformatics (Oxford, England)},
volume = {},
number = {},
pages = {},
doi = {10.1093/bioinformatics/bty1000},
pmid = {30520969},
issn = {1367-4811},
abstract = {Motivation: Histones form octameric complexes called nucleosomes, which organize the genomic DNA of eukaryotes into chromatin. Each nucleosome comprises two copies each of the histones H2A, H2B, H3, and H4, which share a common ancestry. Although histones were initially thought to be a eukaryotic innovation, the subsequent identification of archaeal homologs led to the notion that histones emerged before the divergence of archaea and eukaryotes.<br><br>Results: Here, we report the detection and classification of two new groups of histone homologs, which are present in both archaea and bacteria. Proteins in one group consist of two histone subunits welded into single-chain pseudodimers, whereas in the other they resemble eukaryotic core histone subunits and show sequence patterns characteristic of DNA binding. The sequences come from a broad spectrum of deeply-branching lineages, excluding their genesis by horizontal gene transfer. Our results extend the origin of histones to the Last Universal Common Ancestor.<br><br>Supplementary information: Supplementary data are available at Bioinformatics online.},
}
@article {pmid30519544,
year = {2018},
author = {Higuchi, ML and Kawakami, JT and Ikegami, RN and Reis, MM and Pereira, JJ and Ianni, BM and Buck, P and Oliveira, LMDS and Santos, MHH and Hajjar, LA and Bocchi, EA},
title = {Archaea Symbiont of T. cruzi Infection May Explain Heart Failure in Chagas Disease.},
journal = {Frontiers in cellular and infection microbiology},
volume = {8},
number = {},
pages = {412},
pmid = {30519544},
issn = {2235-2988},
abstract = {Background: Archaeal genes present in Trypanosoma cruzi may represent symbionts that would explain development of heart failure in 30% of Chagas disease patients. Extracellular vesicles in peripheral blood, called exosomes (< 0.1 μm) or microvesicles (>0.1 μm), present in larger numbers in heart failure, were analyzed to determine whether they are derived from archaea in heart failure Chagas disease. Methods: Exosomes and microvesicles in serum supernatant from 3 groups were analyzed: heart failure Chagas disease (N = 26), asymptomatic indeterminate form (N = 21) and healthy non-chagasic control (N = 16). Samples were quantified with transmission electron microscopy, flow cytometer immunolabeled with anti-archaemetzincin-1 antibody (AMZ 1, archaea collagenase) and probe anti-archaeal DNA and zymography to determine AMZ1 (Archaeal metalloproteinase) activity. Results: Indeterminate form patients had higher median numbers of exosomes/case vs. heart failure patients (58.5 vs. 25.5, P < 0.001), higher exosome content of AMZ1 antigens (2.0 vs. 0.0; P < 0.001), and lower archaeal DNA content (0.2 vs. 1.5, P = 0.02). A positive correlation between exosomes and AMZ1 content was seen in indeterminate form (r = 0.5, P < 0.001), but not in heart failure patients (r = 0.002, P = 0.98). Higher free archaeal DNA (63.0 vs. 11.1, P < 0.001) in correlation with exosome numbers (r = 0.66, P = 0.01) was seen in heart failure but not in indeterminate form (r = 0.29, P = 0.10). Flow cytometer showed higher numbers of AMZ1 microvesicles in indeterminate form (64 vs. 36, P = 0.02) and higher archaeal DNA microvesicles in heart failure (8.1 vs. 0.9, P < 0.001). Zymography showed strong% collagenase activity in HF group, mild activity in IF compared to non-chagasic healthy group (121 ± 14, 106 ± 13 and 100; P < 0.001). Conclusions: Numerous exosomes, possibly removing and degrading abnormal AMZ1 collagenase, are associated with indeterminate form. Archaeal microvesicles and their exosomes, possibly associated with release of archaeal AMZ1 in heart failure, are future candidates of heart failure biomarkers if confirmed in larger series, and the therapeutic focus in the treatment of Chagas disease.},
}
@article {pmid30502951,
year = {2018},
author = {Buddeweg, A and Daume, M and Randau, L and Schmitz, RA},
title = {Noncoding RNAs in Archaea: Genome-Wide Identification and Functional Classification.},
journal = {Methods in enzymology},
volume = {612},
number = {},
pages = {413-442},
doi = {10.1016/bs.mie.2018.08.003},
pmid = {30502951},
issn = {1557-7988},
mesh = {Archaea/*genetics ; RNA, Untranslated/*genetics ; Sequence Analysis, RNA ; },
abstract = {Noncoding RNAs (ncRNAs) fulfill essential functions in eukaryotes and bacteria, but also in the third domain of life, the Archaea. Many archaeal organisms live in hostile environments that provide unique challenges for their transcriptional and translational regulatory pathways. Computational analyses and RNA-sequencing methodologies allowed for the genome-wide detection of ncRNA molecules in archaea. Several new classes of ncRNAs have been discovered and are expected to enable life in these extreme habitats. Here, we provide an overview of the current knowledge on archaeal ncRNAs and their deduced or biochemically verified functions. In addition, details of applying RNA-seq methodology for the detection of ncRNAs in Sulfolobus acidocaldarius are provided. Identified ncRNAs include small RNAs (sRNAs) that regulate gene expression and C/D box sRNAs that guide 2'-O methylation of target RNAs.},
}
@article {pmid30514872,
year = {2019},
author = {Zhou, Z and Liu, Y and Lloyd, KG and Pan, J and Yang, Y and Gu, JD and Li, M},
title = {Genomic and transcriptomic insights into the ecology and metabolism of benthic archaeal cosmopolitan, Thermoprofundales (MBG-D archaea).},
journal = {The ISME journal},
volume = {13},
number = {4},
pages = {885-901},
doi = {10.1038/s41396-018-0321-8},
pmid = {30514872},
issn = {1751-7370},
mesh = {Archaea/*classification/genetics/*physiology ; Carbon Cycle ; Ecology ; Genomics ; Geologic Sediments/chemistry/*microbiology ; Metagenome ; Methane/metabolism ; Phylogeny ; RNA, Archaeal/genetics ; RNA, Ribosomal, 16S/genetics ; Transcriptome ; *Water Microbiology ; },
abstract = {Marine Benthic Group D (MBG-D) archaea, discovered by 16S rRNA gene survey decades ago, are ecologically important, yet understudied and uncultured sedimentary archaea. In this study, a comprehensive meta-analysis based on the 16S rRNA genes of MBG-D archaea showed that MBG-D archaea are one of the most frequently found archaeal lineages in global sediment with widespread distribution and high abundance, including 16 subgroups in total. Interestingly, some subgroups show significant segregations toward salinity and methane seeps. Co-occurrence analyses indicate significant non-random association of MBG-D archaea with Lokiarchaeota (in both saline and freshwater sediments) and Hadesarchaea, suggesting potential interactions among these archaeal groups. Meanwhile, based on four nearly complete metagenome-assembled genomes (MAGs) and corresponding metatranscriptomes reconstructed from mangrove and intertidal mudflat sediments, we provide insights on metabolic potentials and ecological functions of MBG-D archaea. MBG-D archaea appear to be capable of transporting and assimilating peptides and generating acetate and ethanol through fermentation. Metatranscriptomic analysis suggests high expression of genes for acetate and amino acid utilization and for peptidases, especially the M09B-type extracellular peptidase (collagenase) showing high expression levels in all four mangrove MAGs. Beyond heterotrophic central carbon metabolism, the MBG-D genomes include genes that might encode two autotrophic pathways: Wood-Ljundahl (WL) pathways using both H4MPT and H4folate as C1 carriers, and an incomplete dicarboxylate/4-hydroxybutyrate cycle with alternative bypasses from pyruvate to malate/oxaloacetate during dicarboxylation. These findings reveal MBG-D archaea as an important ubiquitous benthic sedimentary archaeal group with specific mixotrophic metabolisms, so we proposed the name Thermoprofundales as a new Order within the Class Thermoplasmata. Globally, Thermoprofundales and other benthic archaea might synergistically transform benthic organic matter, possibly playing a vital role in sedimentary carbon cycle.},
}
@article {pmid30511184,
year = {2018},
author = {Vipindas, PV and Jabir, T and Jasmin, C and Balu, T and Rehitha, TV and Adarsh, BM and Nair, S and Abdulla, MH and Abdulaziz, A},
title = {Diversity and seasonal distribution of ammonia-oxidizing archaea in the water column of a tropical estuary along the southeast Arabian Sea.},
journal = {World journal of microbiology &amp; biotechnology},
volume = {34},
number = {12},
pages = {188},
pmid = {30511184},
issn = {1573-0972},
mesh = {Ammonia/*metabolism ; Archaea/*classification/genetics/*metabolism ; Bacteria/classification/genetics/metabolism ; *Biodiversity ; DNA, Archaeal ; DNA, Bacterial/genetics ; Environment ; *Estuaries ; Genes, Archaeal/genetics ; Geologic Sediments/microbiology ; India ; Phylogeny ; RNA, Ribosomal, 16S/genetics ; *Seasons ; Seawater/*microbiology ; Sequence Analysis, DNA ; Tropical Climate ; },
abstract = {Diversity and distribution pattern of ammonia-oxidizing archaea (AOA) were studied across a salinity gradient in the water column of Cochin Estuary (CE), a tropical monsoonal estuary along the southeast Arabian Sea. The water column of CE was found to be nutrient rich with high bacterial (3.7-6.7 × 108 cells L-1) and archaeal abundance (1.9-4.5 × 108 cells L-1). Diversity and seasonal variation in the distribution pattern of AOA were studied using clone library analysis and Denaturing gradient gel electrophoresis (DGGE). Clone library analysis of both the amoA and 16S rRNA gene sequences showed similar diversity pattern, however the diversity was more clear when the 16S rRNA gene sequences were analyzed. More than 70% of the sequences retrieved were clustered under uncultured Thaumarchaeota group 1 lineage and the major fractions of the remaining sequences were grouped into the Nitrosopumilus lineage and Nitrosopelagicus lineage. The AOA community in the CE was less adaptable to changing environmental conditions and its distribution showed seasonal variations within the DGGE banding pattern with higher diversity during the pre-monsoon period. The distribution of AOA also showed its preference to intermediate salinity for their higher diversity. Summer monsoon associated runoff and flushing played a critical role in regulating the seasonality of AOA distribution.},
}
@article {pmid30485275,
year = {2018},
author = {Woodall, LC and Jungblut, AD and Hopkins, K and Hall, A and Robinson, LF and Gwinnett, C and Paterson, GLJ},
title = {Deep-sea anthropogenic macrodebris harbours rich and diverse communities of bacteria and archaea.},
journal = {PloS one},
volume = {13},
number = {11},
pages = {e0206220},
doi = {10.1371/journal.pone.0206220},
pmid = {30485275},
issn = {1932-6203},
mesh = {Archaea/*metabolism ; Atlantic Ocean ; Bacteria/*metabolism ; *Biodiversity ; Biofilms ; Geography ; Geologic Sediments/microbiology ; *Human Activities ; Humans ; Phylogeny ; Seawater ; *Waste Products ; },
abstract = {The deep sea is the largest biome on earth, and microbes dominate in biomass and abundance. Anthropogenic litter is now almost ubiquitous in this biome, and its deposition creates new habitats and environments, including for microbial assemblages. With the ever increasing accumulation of this debris, it is timely to identify and describe the bacterial and archaeal communities that are able to form biofilms on macrodebris in the deep sea. Using 16S rRNA gene high throughput sequencing, we show for the first time the composition of bacteria and archaea on macrodebris collected from the deep sea. Our data suggest differences in the microbial assemblage composition across litter of different materials including metal, rubber, glass, fabric and plastic. These results imply that anthropogenic macrodebris provide diverse habitats for bacterial and archaeal biofilms and each may harbour distinct microbial communities.},
}
@article {pmid30484150,
year = {2018},
author = {Lim, S and Glover, DJ and Clark, DS},
title = {Prefoldins in Archaea.},
journal = {Advances in experimental medicine and biology},
volume = {1106},
number = {},
pages = {11-23},
doi = {10.1007/978-3-030-00737-9_2},
pmid = {30484150},
issn = {0065-2598},
mesh = {*Archaea ; Archaeal Proteins/*physiology ; Molecular Chaperones/*physiology ; *Protein Folding ; },
abstract = {Molecular chaperones promote the correct folding of proteins in aggregation-prone cellular environments by stabilizing nascent polypeptide chains and providing appropriate folding conditions. Prefoldins (PFDs) are molecular chaperones found in archaea and eukaryotes, generally characterized by a unique jellyfish-like hexameric structure consisting of a rigid beta-barrel backbone with protruding flexible coiled-coils. Unlike eukaryotic PFDs that mainly interact with cytoskeletal components, archaeal PFDs can stabilize a wide range of substrates; such versatility reflects PFD's role as a key element in archaeal chaperone systems, which often lack general nascent-chain binding chaperone components such as Hsp70. While archaeal PFDs mainly exist as hexameric complexes, their structural diversity ranges from tetramers to filamentous oligomers. PFDs bind and stabilize nonnative proteins using varying numbers of coiled-coils, and subsequently transfer the substrate to a group II chaperonin (CPN) for refolding. The distinct structure and specific function of archaeal PFDs have been exploited for a broad range of applications in biotechnology; furthermore, a filament-forming variant of PFD has been used to fabricate nanoscale architectures of defined shapes, demonstrating archaeal PFDs' potential applicability in nanotechnology.},
}
@article {pmid30478289,
year = {2019},
author = {Turgeman-Grott, I and Joseph, S and Marton, S and Eizenshtein, K and Naor, A and Soucy, SM and Stachler, AE and Shalev, Y and Zarkor, M and Reshef, L and Altman-Price, N and Marchfelder, A and Gophna, U},
title = {Pervasive acquisition of CRISPR memory driven by inter-species mating of archaea can limit gene transfer and influence speciation.},
journal = {Nature microbiology},
volume = {4},
number = {1},
pages = {177-186},
doi = {10.1038/s41564-018-0302-8},
pmid = {30478289},
issn = {2058-5276},
mesh = {CRISPR-Cas Systems/*genetics ; Clustered Regularly Interspaced Short Palindromic Repeats/*genetics ; DNA, Intergenic/*genetics ; Gene Transfer, Horizontal/*genetics ; Genetic Speciation ; Haloferax mediterranei/*genetics/growth &amp; development ; Haloferax volcanii/*genetics/growth &amp; development ; },
abstract = {CRISPR-Cas systems provide prokaryotes with sequence-specific immunity against viruses and plasmids based on DNA acquired from these invaders, known as spacers. Surprisingly, many archaea possess spacers that match chromosomal genes of related species, including those encoding core housekeeping genes. By sequencing genomes of environmental archaea isolated from a single site, we demonstrate that inter-species spacers are common. We show experimentally, by mating Haloferax volcanii and Haloferax mediterranei, that spacers are indeed acquired chromosome-wide, although a preference for integrated mobile elements and nearby regions of the chromosome exists. Inter-species mating induces increased spacer acquisition and may result in interactions between the acquisition machinery of the two species. Surprisingly, many of the spacers acquired following inter-species mating target self-replicons along with those originating from the mating partner, indicating that the acquisition machinery cannot distinguish self from non-self under these conditions. Engineering the chromosome of one species to be targeted by the other's CRISPR-Cas reduces gene exchange between them substantially. Thus, spacers acquired during inter-species mating could limit future gene transfer, resulting in a role for CRISPR-Cas systems in microbial speciation.},
}
@article {pmid30461142,
year = {2019},
author = {Song, GC and Im, H and Jung, J and Lee, S and Jung, MY and Rhee, SK and Ryu, CM},
title = {Plant growth-promoting archaea trigger induced systemic resistance in Arabidopsis thaliana against Pectobacterium carotovorum and Pseudomonas syringae.},
journal = {Environmental microbiology},
volume = {21},
number = {3},
pages = {940-948},
doi = {10.1111/1462-2920.14486},
pmid = {30461142},
issn = {1462-2920},
support = {KGM2111844//Korea Research Institute of Bioscience and Biotechnology/ ; 918017-4//Ministry of Agriculture, Food and Rural Affairs/ ; Woo Jang-Choon Project (PJ01093904)//Rural Development Administration/ ; },
abstract = {Archaea have inhabited the earth for a long period of time and are ubiquitously distributed in diverse environments. However, few studies have focused on the interactions of archaea with other organisms, including eukaryotes such as plants, since it is difficult to cultivate sufficient numbers of archaeal cells for analysis. In this study, we investigated the interaction between soil archaea and Arabidopsis thaliana. We demonstrate for the first time that soil archaea promote plant growth and trigger induced systemic resistance (ISR) against the necrotrophic bacterium Pectobacterium carotovorum subsp. carotovorum SCC1 and biotrophic bacterium Pseudomonas syringae pv. tomato DC3000. Ammonia-oxidizing archaeon Nitrosocosmicus oleophilus MY3 cells clearly colonized the root surface of Arabidopsis plants, and increased resistance against both pathogenic species via the salicylic acid-independent signalling pathway. This mechanism of bacterial resistance resembles that underlying soil bacteria- and fungi-mediated ISR signalling. Additionally, volatile emissions from N. oleophilus MY3 were identified as major archaeal determinants that elicit ISR. Our results lay a foundation for archaea-plant interactions as a new field of research.},
}
@article {pmid30450139,
year = {2018},
author = {Najafi, A and Moradinasab, M and Seyedabadi, M and Haghighi, MA and Nabipour, I},
title = {First Molecular Identification of Symbiotic Archaea in a Sponge Collected from the Persian Gulf, Iran.},
journal = {The open microbiology journal},
volume = {12},
number = {},
pages = {323-332},
pmid = {30450139},
issn = {1874-2858},
abstract = {Background: Marine sponges are associated with numerically vast and phylogenetically diverse microbial communities at different geographical locations. However, little is known about the archaeal diversity of sponges in the Persian Gulf. The present study was aimed to identify the symbiotic archaea with a sponge species gathered from the Persian Gulf, Iran.<br><br>Methods: Sponge sample was collected from a depth of 3 m offshore Bushehr, Persian Gulf, Iran. Metagenomic DNA was extracted using a hexadecyl trimethyl ammonium bromide (CTAB) method. The COI mtDNA marker was used for molecular taxonomy identification of sponge sample. Also, symbiotic archaea were identified using the culture-independent analysis of the 16S rRNA gene and PCR- cloning.<br><br>Results: In this study, analysis of multilocus DNA marker and morphological characteristics revealed that the sponge species belonged to Chondrilla australiensis isolate PG_BU4. PCR cloning and sequencing showed that all of the sequences of archaeal 16S rRNA gene libraries clustered into the uncultured archaeal group.<br><br>Conclusion: The present study is the first report of the presence of the genus of Chondrilla in the Persian Gulf. Traditional taxonomy methods, when used along with molecular techniques, could play a significant role in the accurate taxonomy of sponges. Also, the uncultured archaea may promise a potential source for bioactive compounds. Further functional studies are needed to explore the role of the sponge-associated uncultured archaea as a part of the marine symbiosis.},
}
@article {pmid30373756,
year = {2019},
author = {Peck, RF and Graham, SM and Gregory, AM},
title = {Species Widely Distributed in Halophilic Archaea Exhibit Opsin-Mediated Inhibition of Bacterioruberin Biosynthesis.},
journal = {Journal of bacteriology},
volume = {201},
number = {2},
pages = {},
doi = {10.1128/JB.00576-18},
pmid = {30373756},
issn = {1098-5530},
support = {P20 GM103423/GM/NIGMS NIH HHS/United States ; },
abstract = {Halophilic Archaea are a distinctive pink color due to a carotenoid pigment called bacterioruberin. To sense or utilize light, many halophilic Archaea also produce rhodopsins, complexes of opsin proteins with a retinal prosthetic group. Both bacterioruberin and retinal are synthesized from isoprenoid precursors, with lycopene as the last shared intermediate. We previously described a regulatory mechanism by which Halobacterium salinarum bacterioopsin and Haloarcula vallismortis cruxopsin inhibit bacterioruberin synthesis catalyzed by lycopene elongase. In this work, we found that opsins in all three major Halobacteria clades inhibit bacterioruberin synthesis, suggesting that this regulatory mechanism existed in the common Halobacteria ancestor. Halophilic Archaea, which are generally heterotrophic and aerobic, likely evolved from an autotrophic, anaerobic methanogenic ancestor by acquiring many genes from Bacteria via lateral gene transfer. These bacterial &quot;imports&quot; include genes encoding opsins and lycopene elongases. To determine if opsins from Bacteria inhibit bacterioruberin synthesis, we tested bacterial opsins and found that an opsin from Curtobacterium, in the Actinobacteria phylum, inhibits bacterioruberin synthesis catalyzed by its own lycopene elongase, as well as that catalyzed by several archaeal enzymes. We also determined that the lycopene elongase from Halococcus salifodinae, a species from a family of Halobacteria lacking opsin homologs, retained the capacity to be inhibited by opsins. Together, our results indicate that opsin-mediated inhibition of bacterioruberin biosynthesis is a widely distributed mechanism found in both Archaea and Bacteria, possibly predating the divergence of the two domains. Further analysis may provide insight into the acquisition and evolution of the genes and their host species.IMPORTANCE All organisms use a variety of mechanisms to allocate limited resources to match their needs in their current environment. Here, we explore how halophilic microbes use a novel mechanism to allow efficient production of rhodopsin, a complex of an opsin protein and a retinal prosthetic group. We previously demonstrated that Halobacterium salinarum bacterioopsin directs available resources toward retinal by inhibiting synthesis of bacterioruberin, a molecule that shares precursors with retinal. In this work, we show that this mechanism can be carried out by proteins from halophilic Archaea that are not closely related to H. salinarum and those in at least one species of Bacteria Therefore, opsin-mediated inhibition of bacterioruberin synthesis may be a highly conserved, ancient regulatory mechanism.},
}
@article {pmid30370585,
year = {2019},
author = {Seth-Pasricha, M and Senn, S and Sanman, LE and Bogyo, M and Nanda, V and Bidle, KA and Bidle, KD},
title = {Catalytic linkage between caspase activity and proteostasis in Archaea.},
journal = {Environmental microbiology},
volume = {21},
number = {1},
pages = {286-298},
doi = {10.1111/1462-2920.14456},
pmid = {30370585},
issn = {1462-2920},
support = {3789//Gordon and Betty Moore Foundation/ ; },
abstract = {The model haloarchaeon, Haloferax volcanii possess an extremely high, and highly specific, basal caspase activity in exponentially growing cells that closely resembles caspase-4. This activity is specifically inhibited by the pan-caspase inhibitor, z-VAD-FMK, and has no cross-reactivity with other known protease families. Although it is one of the dominant cellular proteolytic activities in exponentially growing H. volcanii cells, the interactive cellular roles remain unknown and the protein(s) responsible for this activity remain elusive. Here, biochemical purification and in situ trapping with caspase targeted covalent inhibitors combined with genome-enabled proteomics, structural analysis, targeted gene knockouts and treatment with canavanine demonstrated a catalytic linkage between caspase activity and thermosomes, proteasomes and cdc48b, a cell division protein and proteasomal degradation facilitating ATPase, as part of an 'interactase' of stress-related protein complexes with an established link to the unfolded protein response (UPR). Our findings provide novel cellular and biochemical context for the observed caspase activity in Archaea and add new insight to understanding the role of this activity, implicating their possible role in the establishment of protein stress and ER associated degradation pathways in Eukarya.},
}
@article {pmid30357005,
year = {2018},
author = {Harish, A},
title = {What is an archaeon and are the Archaea really unique?.},
journal = {PeerJ},
volume = {6},
number = {},
pages = {e5770},
pmid = {30357005},
issn = {2167-8359},
abstract = {The recognition of the group Archaea as a major branch of the tree of life (ToL) prompted a new view of the evolution of biodiversity. The genomic representation of archaeal biodiversity has since significantly increased. In addition, advances in phylogenetic modeling of multi-locus datasets have resolved many recalcitrant branches of the ToL. Despite the technical advances and an expanded taxonomic representation, two important aspects of the origins and evolution of the Archaea remain controversial, even as we celebrate the 40th anniversary of the monumental discovery. These issues concern (i) the uniqueness (monophyly) of the Archaea, and (ii) the evolutionary relationships of the Archaea to the Bacteria and the Eukarya; both of these are relevant to the deep structure of the ToL. To explore the causes for this persistent ambiguity, I examine multiple datasets and different phylogenetic approaches that support contradicting conclusions. I find that the uncertainty is primarily due to a scarcity of information in standard datasets-universal core-genes datasets-to reliably resolve the conflicts. These conflicts can be resolved efficiently by comparing patterns of variation in the distribution of functional genomic signatures, which are less diffused unlike patterns of primary sequence variation. Relatively lower heterogeneity in distribution patterns minimizes uncertainties and supports statistically robust phylogenetic inferences, especially of the earliest divergences of life. This case study further highlights the limitations of primary sequence data in resolving difficult phylogenetic problems, and raises questions about evolutionary inferences drawn from the analyses of sequence alignments of a small set of core genes. In particular, the findings of this study corroborate the growing consensus that reversible substitution mutations may not be optimal phylogenetic markers for resolving early divergences in the ToL, nor for determining the polarity of evolutionary transitions across the ToL.},
}
@article {pmid30343425,
year = {2018},
author = {Pornkulwat, P and Kurisu, F and Soonglerdsongpha, S and Banjongproo, P and Srithep, P and Limpiyakorn, T},
title = {Incorporation of 13C-HCO3- by ammonia-oxidizing archaea and bacteria during ammonia oxidation of sludge from a municipal wastewater treatment plant.},
journal = {Applied microbiology and biotechnology},
volume = {102},
number = {24},
pages = {10767-10777},
doi = {10.1007/s00253-018-9436-0},
pmid = {30343425},
issn = {1432-0614},
support = {RSA5780036//Thailand Research Fund (TH)/ ; PHD/0103/2558//Thailand Research Fund/ ; },
mesh = {Ammonia/*metabolism ; Archaea/genetics/*metabolism ; Bacteria/genetics/*metabolism ; Bicarbonates/metabolism ; Carbon Isotopes/*metabolism ; DNA Primers ; Oxidation-Reduction ; Phylogeny ; Polymerase Chain Reaction ; Sewage ; Thailand ; Waste Disposal, Fluid/*methods ; },
abstract = {Ammonia-oxidizing archaea (AOA) have recently been proposed as potential players for ammonia removal in wastewater treatment plants (WWTPs). However, there is little evidence directly showing the contribution of AOA to ammonia oxidation in these engineered systems. In this study, DNA-stable isotope probing (DNA-SIP) with labeled 13C-HCO3- was introduced to sludge from a municipal WWTP. Quantitative PCR demonstrated that AOA amoA genes outnumbered AOB amoA genes in this WWTP sludge. AOA amoA gene sequence analysis revealed that AOA present in this WWTP were specific to one subcluster within the group 1.1b Thaumarchaeota. When ammonia was supplied to DNA-SIP incubation, the DNA-SIP profiles demonstrated the incorporation of the 13C into AOA and AOB. However, the 13C was not found to be assimilated into both microorganisms in the incubation without ammonia. Specific primers were designed to target amoA genes of AOA belonging to the subcluster found in this WWTP. Applying the primers to DNA-SIP experiment revealed that AOA of this subcluter most likely utilized inorganic carbon during ammonia oxidation under the studied conditions.},
}
@article {pmid30342933,
year = {2018},
author = {Lemor, M and Kong, Z and Henry, E and Brizard, R and Laurent, S and Bossé, A and Henneke, G},
title = {Differential Activities of DNA Polymerases in Processing Ribonucleotides during DNA Synthesis in Archaea.},
journal = {Journal of molecular biology},
volume = {430},
number = {24},
pages = {4908-4924},
doi = {10.1016/j.jmb.2018.10.004},
pmid = {30342933},
issn = {1089-8638},
abstract = {Consistent with the fact that ribonucleotides (rNTPs) are in excess over deoxyribonucleotides (dNTPs) in vivo, recent findings indicate that replicative DNA polymerases (DNA Pols) are able to insert ribonucleotides (rNMPs) during DNA synthesis, raising crucial questions about the fidelity of DNA replication in both Bacteria and Eukarya. Here, we report that the level of rNTPs is 20-fold higher than that of dNTPs in Pyrococcus abyssi cells. Using dNTP and rNTP concentrations present in vivo, we recorded rNMP incorporation in a template-specific manner during in vitro synthesis, with the family-D DNA Pol (PolD) having the highest propensity compared with the family-B DNA Pol and the p41/p46 complex. We also showed that ribonucleotides accumulate at a relatively high frequency in the genome of wild-type Thermococcales cells, and this frequency significantly increases upon deletion of RNase HII, the major enzyme responsible for the removal of RNA from DNA. Because ribonucleotides remain in genomic DNA, we then analyzed the effects on polymerization activities by the three DNA Pols. Depending on the identity of the base and the sequence context, all three DNA Pols bypass rNMP-containing DNA templates with variable efficiency and nucleotide (mis)incorporation ability. Unexpectedly, we found that PolD correctly base-paired a single ribonucleotide opposite rNMP-containing DNA templates. An evolutionary scenario is discussed concerning rNMP incorporation into DNA and genome stability.},
}
@article {pmid30327333,
year = {2019},
author = {Huang, L and Ashraf, S and Lilley, DMJ},
title = {The role of RNA structure in translational regulation by L7Ae protein in archaea.},
journal = {RNA (New York, N.Y.)},
volume = {25},
number = {1},
pages = {60-69},
doi = {10.1261/rna.068510.118},
pmid = {30327333},
issn = {1469-9001},
mesh = {5' Untranslated Regions ; Archaeal Proteins/*chemistry/genetics/*metabolism ; Archaeoglobus fulgidus/genetics/metabolism ; Base Sequence ; Binding Sites/genetics ; Crystallography, X-Ray ; Models, Molecular ; Nucleic Acid Conformation ; Protein Binding ; Protein Biosynthesis ; Protein Conformation ; RNA Stability ; RNA, Archaeal/*chemistry/genetics/*metabolism ; RNA, Messenger/chemistry/genetics/metabolism ; Ribosomal Proteins/*chemistry/genetics/*metabolism ; },
abstract = {A recent study has shown that archaeal L7Ae binds to a putative k-turn structure in the 5'-leader of the mRNA of its structural gene to regulate translation. To function as a regulator, the RNA should be unstructured in the absence of protein, but it should adopt a k-turn-containing stem-loop on binding L7Ae. Sequence analysis of UTR sequences indicates that their k-turn elements will be unable to fold in the absence of L7Ae, and we have demonstrated this experimentally in solution using FRET for the Archaeoglobus fulgidus sequence. We have solved the X-ray crystal structure of the complex of the A. fulgidus RNA bound to its cognate L7Ae protein. The RNA adopts a standard k-turn conformation that is specifically recognized by the L7Ae protein, so stabilizing the stem-loop. In-line probing of the natural-sequence UTR shows that the RNA is unstructured in the absence of L7Ae binding, but folds on binding the protein such that the ribosome binding site is occluded. Thus, L7Ae regulates its own translation by switching the conformation of the RNA to alter accessibility.},
}
@article {pmid30323263,
year = {2019},
author = {Rinke, C and Rubino, F and Messer, LF and Youssef, N and Parks, DH and Chuvochina, M and Brown, M and Jeffries, T and Tyson, GW and Seymour, JR and Hugenholtz, P},
title = {A phylogenomic and ecological analysis of the globally abundant Marine Group II archaea (Ca. Poseidoniales ord. nov.).},
journal = {The ISME journal},
volume = {13},
number = {3},
pages = {663-675},
doi = {10.1038/s41396-018-0282-y},
pmid = {30323263},
issn = {1751-7370},
mesh = {Adaptation, Physiological ; Archaea/*genetics/isolation &amp; purification ; Biological Evolution ; Ecology ; *Gene Transfer, Horizontal ; Genome, Archaeal/*genetics ; *Metagenome ; Oceans and Seas ; Phylogeny ; Plankton/*genetics/isolation &amp; purification ; Rhodopsins, Microbial/*genetics ; Seawater ; },
abstract = {Marine Group II (MGII) archaea represent the most abundant planktonic archaeal group in ocean surface waters, but our understanding of the group has been limited by a lack of cultured representatives and few sequenced genomes. Here, we conducted a comparative phylogenomic analysis of 270 recently available MGII metagenome-assembled genomes (MAGs) to investigate their evolution and ecology. Based on a rank-normalised genome phylogeny, we propose that MGII is an order-level lineage for which we propose the name Candidatus Poseidoniales (after Gr. n. Poseidon, God of the sea), comprising the families Candidatus Poseidonaceae fam. nov. (formerly subgroup MGIIa) and Candidatus Thalassarchaeaceae fam. nov. (formerly subgroup MGIIb). Within these families, 21 genera could be resolved, many of which had distinct biogeographic ranges and inferred nutrient preferences. Phylogenetic analyses of key metabolic functions suggest that the ancestor of Ca. Poseidoniales was a surface water-dwelling photoheterotroph that evolved to occupy multiple related ecological niches based primarily on spectral tuning of proteorhodopsin genes. Interestingly, this adaptation appears to involve an overwrite mechanism whereby an existing single copy of the proteorhodopsin gene is replaced by a horizontally transferred copy, which in many instances should allow an abrupt change in light absorption capacity. Phototrophy was lost entirely from five Ca. Poseidoniales genera coinciding with their adaptation to deeper aphotic waters. We also report the first instances of nitrate reductase in two genera acquired via horizontal gene transfer (HGT), which was a potential adaptation to oxygen limitation. Additional metabolic traits differentiating families and genera include flagellar-based adhesion, transporters, and sugar, amino acid, and peptide degradation. Our results suggest that HGT has shaped the evolution of Ca. Poseidoniales to occupy a variety of ecological niches and to become the most successful archaeal lineage in ocean surface waters.},
}
@article {pmid30302054,
year = {2018},
author = {Yin, Z and Bi, X and Xu, C},
title = {Ammonia-Oxidizing Archaea (AOA) Play with Ammonia-Oxidizing Bacteria (AOB) in Nitrogen Removal from Wastewater.},
journal = {Archaea (Vancouver, B.C.)},
volume = {2018},
number = {},
pages = {8429145},
pmid = {30302054},
issn = {1472-3654},
mesh = {Ammonia/*metabolism ; Archaea/growth &amp; development/*metabolism ; Bacteria/growth &amp; development/*metabolism ; *Microbial Interactions ; Nitrogen/*metabolism ; Oxidation-Reduction ; Waste Water/*microbiology ; Water Purification/methods ; },
abstract = {An increase in the number of publications in recent years indicates that besides ammonia-oxidizing bacteria (AOB), ammonia-oxidizing archaea (AOA) may play an important role in nitrogen removal from wastewater, gaining wide attention in the wastewater engineering field. This paper reviews the current knowledge on AOA and AOB involved in wastewater treatment systems and summarises the environmental factors affecting AOA and AOB. Current findings reveal that AOA have stronger environmental adaptability compared with AOB under extreme environmental conditions (such as low temperature and low oxygen level). However, there is still little information on the cooperation and competition relationship between AOA and AOB, and other microbes related to nitrogen removal, which needs further exploration. Furthermore, future studies are proposed to develop novel nitrogen removal processes dominated by AOA by parameter optimization.},
}
@article {pmid30294305,
year = {2018},
author = {Genderjahn, S and Alawi, M and Mangelsdorf, K and Horn, F and Wagner, D},
title = {Desiccation- and Saline-Tolerant Bacteria and Archaea in Kalahari Pan Sediments.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {2082},
pmid = {30294305},
issn = {1664-302X},
abstract = {More than 41% of the Earth's land area is covered by permanent or seasonally arid dryland ecosystems. Global development and human activity have led to an increase in aridity, resulting in ecosystem degradation and desertification around the world. The objective of the present work was to investigate and compare the microbial community structure and geochemical characteristics of two geographically distinct saline pan sediments in the Kalahari Desert of southern Africa. Our data suggest that these microbial communities have been shaped by geochemical drivers, including water content, salinity, and the supply of organic matter. Using Illumina 16S rRNA gene sequencing, this study provides new insights into the diversity of bacteria and archaea in semi-arid, saline, and low-carbon environments. Many of the observed taxa are halophilic and adapted to water-limiting conditions. The analysis reveals a high relative abundance of halophilic archaea (primarily Halobacteria), and the bacterial diversity is marked by an abundance of Gemmatimonadetes and spore-forming Firmicutes. In the deeper, anoxic layers, candidate division MSBL1, and acetogenic bacteria (Acetothermia) are abundant. Together, the taxonomic information and geochemical data suggest that acetogenesis could be a prevalent form of metabolism in the deep layers of a saline pan.},
}
@article {pmid30291304,
year = {2018},
author = {Du Toit, A},
title = {Profilin(g) Asgard archaea.},
journal = {Nature reviews. Microbiology},
volume = {16},
number = {12},
pages = {717},
doi = {10.1038/s41579-018-0100-6},
pmid = {30291304},
issn = {1740-1534},
}
@article {pmid30283132,
year = {2018},
author = {Akıl, C and Robinson, RC},
title = {Genomes of Asgard archaea encode profilins that regulate actin.},
journal = {Nature},
volume = {562},
number = {7727},
pages = {439-443},
doi = {10.1038/s41586-018-0548-6},
pmid = {30283132},
issn = {1476-4687},
mesh = {Actin Cytoskeleton/metabolism ; Actins/chemistry/*metabolism ; Amino Acid Motifs ; Animals ; Archaea/cytology/*genetics/*metabolism ; Cell Movement ; Endocytosis ; Eukaryotic Cells/cytology/metabolism ; *Evolution, Molecular ; Genome, Archaeal/*genetics ; Humans ; Models, Molecular ; Peptides/chemistry/metabolism ; Phospholipids/metabolism/pharmacology ; Phylogeny ; Polymerization ; Profilins/chemistry/*genetics/*metabolism ; Protein Binding/drug effects ; Rabbits ; },
abstract = {The origin of the eukaryotic cell is unresolved1,2. Metagenomics sequencing has recently identified several potential eukaryotic gene homologues in Asgard archaea3,4, consistent with the hypothesis that the eukaryotic cell evolved from within the Archaea domain. However, many of these eukaryotic-like sequences are highly divergent and the organisms have yet to be imaged or cultivated, which brings into question the extent to which these archaeal proteins represent functional equivalents of their eukaryotic counterparts. Here we show that Asgard archaea encode functional profilins and thereby establish that this archaeal superphylum has a regulated actin cytoskeleton, one of the hallmarks of the eukaryotic cell5. Loki profilin-1, Loki profilin-2 and Odin profilin adopt the typical profilin fold and are able to interact with rabbit actin-an interaction that involves proteins from species that diverged more than 1.2 billion years ago6. Biochemical experiments reveal that mammalian actin polymerizes in the presence of Asgard profilins; however, Loki, Odin and Heimdall profilins impede pointed-end elongation. These archaeal profilins also retard the spontaneous nucleation of actin filaments, an effect that is reduced in the presence of phospholipids. Asgard profilins do not interact with polyproline motifs and the profilin-polyproline interaction therefore probably evolved later in the Eukarya lineage. These results suggest that Asgard archaea possess a primordial, polar, profilin-regulated actin system, which may be localized to membranes owing to the sensitivity of Asgard profilins to phospholipids. Because Asgard archaea are also predicted to encode potential eukaryotic-like genes involved in membrane-trafficking and endocytosis3,4, imaging is now necessary to elucidate whether these organisms are capable of generating eukaryotic-like membrane dynamics that are regulated by actin, such as are observed in eukaryotic cell movement, podosomes and endocytosis.},
}
@article {pmid30283097,
year = {2018},
author = {Ramezani, A and Nolin, TD and Barrows, IR and Serrano, MG and Buck, GA and Regunathan-Shenk, R and West, RE and Latham, PS and Amdur, R and Raj, DS},
title = {Gut Colonization with Methanogenic Archaea Lowers Plasma Trimethylamine N-oxide Concentrations in Apolipoprotein e-/- Mice.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {14752},
pmid = {30283097},
issn = {2045-2322},
abstract = {A mechanistic link between trimethylamine N-oxide (TMAO) and atherogenesis has been reported. TMAO is generated enzymatically in the liver by the oxidation of trimethylamine (TMA), which is produced from dietary choline, carnitine and betaine by gut bacteria. It is known that certain members of methanogenic archaea (MA) could use methylated amines such as trimethylamine as growth substrates in culture. Therefore, we investigated the efficacy of gut colonization with MA on lowering plasma TMAO concentrations. Initially, we screened for the colonization potential and TMAO lowering efficacy of five MA species in C57BL/6 mice fed with high choline/TMA supplemented diet, and found out that all five species could colonize and lover plasma TMAO levels, although with different efficacies. The top performing MA, Methanobrevibacter smithii, Methanosarcina mazei, and Methanomicrococcus blatticola, were transplanted into Apoe-/- mice fed with high choline/TMA supplemented diet. Similar to C57BL/6 mice, following initial provision of the MA, there was progressive attrition of MA within fecal microbial communities post-transplantation during the initial 3 weeks of the study. In general, plasma TMAO concentrations decreased significantly in proportion to the level of MA colonization. In a subsequent experiment, use of antibiotics and repeated transplantation of Apoe-/- mice with M. smithii, led to high engraftment levels during the 9 weeks of the study, resulting in a sustained and significantly lower average plasma TMAO concentrations (18.2 ± 19.6 μM) compared to that in mock-transplanted control mice (120.8 ± 13.0 μM, p < 0.001). Compared to control Apoe-/- mice, M. smithii-colonized mice also had a 44% decrease in aortic plaque area (8,570 μm [95% CI 19587-151821] vs. 15,369 μm [95% CI [70058-237321], p = 0.34), and 52% reduction in the fat content in the atherosclerotic plaques (14,283 μm [95% CI 4,957-23,608] vs. 29,870 μm [95% CI 18,074-41,666], p = 0.10), although these differences did not reach significance. Gut colonization with M. smithii leads to a significant reduction in plasma TMAO levels, with a tendency for attenuation of atherosclerosis burden in Apoe-/- mice. The anti-atherogenic potential of MA should be further tested in adequately powered experiments.},
}
@article {pmid30278423,
year = {2019},
author = {Duan, P and Fan, C and Zhang, Q and Xiong, Z},
title = {Overdose fertilization induced ammonia-oxidizing archaea producing nitrous oxide in intensive vegetable fields.},
journal = {The Science of the total environment},
volume = {650},
number = {Pt 2},
pages = {1787-1794},
doi = {10.1016/j.scitotenv.2018.09.341},
pmid = {30278423},
issn = {1879-1026},
mesh = {Ammonia/*metabolism ; Archaea/*metabolism ; China ; Dose-Response Relationship, Drug ; *Fertilizers ; Nitrogen/*administration &amp; dosage ; Nitrous Oxide/*metabolism ; Oxidation-Reduction ; Seasons ; *Soil Microbiology ; Vegetables/growth &amp; development ; },
abstract = {Little is known about the effects of nitrogen (N) fertilization rates on ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) and their differential contribution to nitrous oxide (N2O) production, particularly in greenhouse based high N input vegetable soils. Six N treatments (N1, N2, N3, N4, N5 and N6 representing 0, 293, 587, 880, 1173 and 1760 kg N ha-1 yr-1, respectively) were continuously managed for three years in a typically intensified vegetable field in China. The aerobic incubation experiment involving these field-treated soils was designed to evaluate the relative contributions of AOA and AOB to N2O production by using acetylene or 1-octyne as inhibitors. The results showed that the soil pH and net nitrification rate gradually declined with increasing the fertilizer N application rates. The AOA were responsible for 44-71% of the N2O production with negligible N2O from AOB in urea unamended control soils. With urea amendment, the AOA were responsible for 48-53% of the N2O production in the excessively fertilized soils, namely the N5-N6 soils, while the AOB were responsible for 42-55% in the conventionally fertilized soils, namely the N1-N4 soils. Results indicated that overdose fertilization induced higher AOA-dependent N2O production than AOB, whereas urea supply led to higher AOB-dependent N2O production than AOA in conventionally fertilized soils. Additionally, a positive relationship existed between N2O production and NO2- accumulation during the incubation. Further mechanisms for NO2--dependent N2O production in intensive vegetable soils therefore deserve urgent attention.},
}
@article {pmid30258074,
year = {2018},
author = {Cheung, MK and Wong, CK and Chu, KH and Kwan, HS},
title = {Community Structure, Dynamics and Interactions of Bacteria, Archaea and Fungi in Subtropical Coastal Wetland Sediments.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {14397},
pmid = {30258074},
issn = {2045-2322},
abstract = {Bacteria, archaea and fungi play crucial roles in wetland biogeochemical processes. However, little is known about their community structure, dynamics and interactions in subtropical coastal wetlands. Here, we examined communities of the three kingdoms in mangrove and mudflat sediments of a subtropical coastal wetland using Ion Torrent amplicon sequencing and co-occurrence network analysis. Bacterial, archaeal and fungal communities comprised mainly of members from the phyla Proteobacteria and Bacteroidetes, Bathyarchaeota and Euryarchaeota, and Ascomycota, respectively. Species richness and Shannon diversity were highest in bacteria, followed by archaea and were lowest in fungi. Distinct spatiotemporal patterns were observed, with bacterial and fungal communities varying, to different extent, between wet and dry seasons and between mangrove and mudflat, and archaeal community remaining relatively stable between seasons and regions. Redundancy analysis revealed temperature as the major driver of the seasonal patterns of bacterial and fungal communities but also highlighted the importance of interkingdom biotic factors in shaping the community structure of all three kingdoms. Potential ecological interactions and putative keystone taxa were identified based on co-occurrence network analysis. These findings facilitate current understanding of the microbial ecology of subtropical coastal wetlands and provide a basis for better modelling of ecological processes in this important ecosystem.},
}
@article {pmid30254509,
year = {2018},
author = {Krzmarzick, MJ and Taylor, DK and Fu, X and McCutchan, AL},
title = {Diversity and Niche of Archaea in Bioremediation.},
journal = {Archaea (Vancouver, B.C.)},
volume = {2018},
number = {},
pages = {3194108},
pmid = {30254509},
issn = {1472-3654},
mesh = {Archaea/*growth &amp; development/*metabolism ; *Biodegradation, Environmental ; Environmental Pollutants/*metabolism ; Hydrocarbons/metabolism ; },
abstract = {Bioremediation is the use of microorganisms for the degradation or removal of contaminants. Most bioremediation research has focused on processes performed by the domain Bacteria; however, Archaea are known to play important roles in many situations. In extreme conditions, such as halophilic or acidophilic environments, Archaea are well suited for bioremediation. In other conditions, Archaea collaboratively work alongside Bacteria during biodegradation. In this review, the various roles that Archaea have in bioremediation is covered, including halophilic hydrocarbon degradation, acidophilic hydrocarbon degradation, hydrocarbon degradation in nonextreme environments such as soils and oceans, metal remediation, acid mine drainage, and dehalogenation. Research needs are addressed in these areas. Beyond bioremediation, these processes are important for wastewater treatment (particularly industrial wastewater treatment) and help in the understanding of the natural microbial ecology of several Archaea genera.},
}
@article {pmid30254323,
year = {2019},
author = {Lambert, S and Tragin, M and Lozano, JC and Ghiglione, JF and Vaulot, D and Bouget, FY and Galand, PE},
title = {Rhythmicity of coastal marine picoeukaryotes, bacteria and archaea despite irregular environmental perturbations.},
journal = {The ISME journal},
volume = {13},
number = {2},
pages = {388-401},
doi = {10.1038/s41396-018-0281-z},
pmid = {30254323},
issn = {1751-7370},
mesh = {Archaea/classification/*genetics/physiology ; Bacteria/*classification/genetics ; Ecosystem ; Eukaryota/classification/*genetics ; Mediterranean Sea ; Phytoplankton/growth &amp; development ; Seasons ; Seawater/*microbiology ; },
abstract = {Seasonality in marine microorganisms has been classically observed in phytoplankton blooms, and more recently studied at the community level in prokaryotes, but rarely investigated at the scale of individual microbial taxa. Here we test if specific marine eukaryotic phytoplankton, bacterial and archaeal taxa display yearly rhythms at a coastal site impacted by irregular environmental perturbations. Our seven-year study in the Bay of Banyuls (North Western Mediterranean Sea) shows that despite some fluctuating environmental conditions, many microbial taxa displayed significant yearly rhythms. The robust rhythmicity was found in both autotrophs (picoeukaryotes and cyanobacteria) and heterotrophic prokaryotes. Sporadic meteorological events and irregular nutrient supplies did, however, trigger the appearance of less common non-rhythmic taxa. Among the environmental parameters that were measured, the main drivers of rhythmicity were temperature and day length. Seasonal autotrophs may thus be setting the pace for rhythmic heterotrophs. Similar environmental niches may be driving seasonality as well. The observed strong association between Micromonas and SAR11, which both need thiamine precursors for growth, could be a first indication that shared nutritional niches may explain some rhythmic patterns of co-occurrence.},
}
@article {pmid30254075,
year = {2018},
author = {Michael, AJ},
title = {Polyamine function in archaea and bacteria.},
journal = {The Journal of biological chemistry},
volume = {293},
number = {48},
pages = {18693-18701},
pmid = {30254075},
issn = {1083-351X},
mesh = {Archaea/chemistry/genetics/growth &amp; development/*metabolism ; Archaeal Proteins/genetics/metabolism ; Bacteria/chemistry/genetics/growth &amp; development/*metabolism ; Bacterial Proteins/genetics/metabolism ; Polyamines/chemistry/*metabolism ; },
abstract = {Most of the phylogenetic diversity of life is found in bacteria and archaea, and is reflected in the diverse metabolism and functions of bacterial and archaeal polyamines. The polyamine spermidine was probably present in the last universal common ancestor, and polyamines are known to be necessary for critical physiological functions in bacteria, such as growth, biofilm formation, and other surface behaviors, and production of natural products, such as siderophores. There is also phylogenetic diversity of function, indicated by the role of polyamines in planktonic growth of different species, ranging from absolutely essential to entirely dispensable. However, the cellular molecular mechanisms responsible for polyamine function in bacterial growth are almost entirely unknown. In contrast, the molecular mechanisms of essential polyamine functions in archaea are better understood: covalent modification by polyamines of translation factor aIF5A and the agmatine modification of tRNAIle As with bacterial hyperthermophiles, archaeal thermophiles require long-chain and branched polyamines for growth at high temperatures. For bacterial species in which polyamines are essential for growth, it is still unknown whether the molecular mechanisms underpinning polyamine function involve covalent or noncovalent interactions. Understanding the cellular molecular mechanisms of polyamine function in bacterial growth and physiology remains one of the great challenges for future polyamine research.},
}
@article {pmid30250155,
year = {2018},
author = {Wolfe, JM and Fournier, GP},
title = {Reply to 'Molecular clocks provide little information to date methanogenic Archaea'.},
journal = {Nature ecology &amp; evolution},
volume = {2},
number = {11},
pages = {1678},
doi = {10.1038/s41559-018-0685-1},
pmid = {30250155},
issn = {2397-334X},
mesh = {*Archaea ; *Soil Microbiology ; },
}
@article {pmid30250154,
year = {2018},
author = {Roger, AJ and Susko, E},
title = {Molecular clocks provide little information to date methanogenic Archaea.},
journal = {Nature ecology &amp; evolution},
volume = {2},
number = {11},
pages = {1676-1677},
doi = {10.1038/s41559-018-0687-z},
pmid = {30250154},
issn = {2397-334X},
mesh = {Archaea/*genetics ; *Gene Transfer, Horizontal ; Phylogeny ; Soil Microbiology ; },
}
@article {pmid30245679,
year = {2018},
author = {Zaretsky, M and Roine, E and Eichler, J},
title = {Sialic Acid-Like Sugars in Archaea: Legionaminic Acid Biosynthesis in the Halophile Halorubrum sp. PV6.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {2133},
pmid = {30245679},
issn = {1664-302X},
abstract = {N-glycosylation is a post-translational modification that occurs in all three domains. In Archaea, however, N-linked glycans present a degree of compositional diversity not observed in either Eukarya or Bacteria. As such, it is surprising that nonulosonic acids (NulOs), nine-carbon sugars that include sialic acids, pseudaminic acids, and legionaminic acids, are routinely detected as components of protein-linked glycans in Eukarya and Bacteria but not in Archaea. In the following, we report that the N-linked glycan attached to the S-layer glycoprotein of the haloarchaea Halorubrum sp. PV6 includes an N-formylated legionaminic acid. Analysis of the Halorubrum sp. PV6 genome led to the identification of sequences predicted to comprise the legionaminic acid biosynthesis pathway. The transcription of pathway genes was confirmed, as was the co-transcription of several of these genes. In addition, the activities of LegI, which catalyzes the condensation of 2,4-di-N-acetyl-6-deoxymannose and phosphoenolpyruvate to generate legionaminic acid, and LegF, which catalyzes the addition of cytidine monophosphate (CMP) to legionaminic acid, both heterologously expressed in Haloferax volcanii, were demonstrated. Further genome analysis predicts that the genes encoding enzymes of the legionaminic acid biosynthetic pathway are clustered together with sequences seemingly encoding components of the N-glycosylation pathway in this organism. In defining the first example of a legionaminic acid biosynthesis pathway in Archaea, the findings reported here expand our insight into archaeal N-glycosylation, an almost universal post-translational modification in this domain of life.},
}
@article {pmid30241308,
year = {2018},
author = {Maupin-Furlow, JA},
title = {Methionine Sulfoxide Reductases of Archaea.},
journal = {Antioxidants (Basel, Switzerland)},
volume = {7},
number = {10},
pages = {},
pmid = {30241308},
issn = {2076-3921},
support = {NSF 1642283//JM-F through the Bilateral NSF/BIO-BBSRC program/ ; DOE DE-FG02-05ER15650//the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences, Physical Biosciences Program/ ; NIH R01 GM57498//National Institutes of Health/ ; },
abstract = {Methionine sulfoxide reductases are found in all domains of life and are important in reversing the oxidative damage of the free and protein forms of methionine, a sulfur containing amino acid particularly sensitive to reactive oxygen species (ROS). Archaea are microbes of a domain of life distinct from bacteria and eukaryotes. Archaea are well known for their ability to withstand harsh environmental conditions that range from habitats of high ROS, such as hypersaline lakes of intense ultraviolet (UV) radiation and desiccation, to hydrothermal vents of low concentrations of dissolved oxygen at high temperature. Recent evidence reveals the methionine sulfoxide reductases of archaea function not only in the reduction of methionine sulfoxide but also in the ubiquitin-like modification of protein targets during oxidative stress, an association that appears evolutionarily conserved in eukaryotes. Here is reviewed methionine sulfoxide reductases and their distribution and function in archaea.},
}
@article {pmid30233557,
year = {2018},
author = {Eger, M and Graz, M and Riede, S and Breves, G},
title = {Application of MootralTM Reduces Methane Production by Altering the Archaea Community in the Rumen Simulation Technique.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {2094},
pmid = {30233557},
issn = {1664-302X},
abstract = {The reduction of methane emissions by ruminants is a highly desirable goal to mitigate greenhouse gas emissions. Various feed additives have already been tested for their ability to decrease methane production; however, practical use is often limited due to negative effects on rumen fermentation or high costs. Organosulphur compounds from garlic (Allium sativum) and flavonoids have been identified as promising plant-derived compounds which are able to reduce methane production. Here, we evaluated the effects of a combination of garlic powder and bitter orange (Citrus aurantium) extracts, Mootral, on ruminal methane production, ruminal fermentation and the community of methanogenic Archaea by using the rumen simulation technique as ex vivo model. The experiment consisted of an equilibration period of 7 days, an experimental period of 8 days and a withdrawal period of 4 days. During the experimental period three fermenters each were either treated as controls (CON), received a low dose of Mootral (LD), a high dose of Mootral (HD), or monensin (MON) as positive control. Application of Mootral strongly reduced the proportion of methane in the fermentation gas and the production rate of methane. Moreover, the experimental mixture induced a dose-dependent increase in the production rate of short chain fatty acids and in the molar proportion of butyrate. Some effects persisted during the withdrawal period. Both, single strand conformation polymorphism and Illumina MiSeq 16S rRNA amplicon sequencing indicated an archaeal community distinct from CON and MON samples in the LD and HD samples. Among archaeal families the percentage of Methanobacteriaceae was reduced during application of both doses of Mootral. Moreover, several significant differences were observed on OTU level among treatment groups and after withdrawal of the additives for LD and HD group. At day 14, 4 OTUs were positively correlated with methane production. In conclusion this mixture of garlic and citrus compounds appears to effectively reduce methane production by alteration of the archaeal community without exhibiting negative side effects on rumen fermentation.},
}
@article {pmid30223159,
year = {2018},
author = {Ren, L and Cai, C and Zhang, J and Yang, Y and Wu, G and Luo, L and Huang, H and Zhou, Y and Qin, P and Yu, M},
title = {Key environmental factors to variation of ammonia-oxidizing archaea community and potential ammonia oxidation rate during agricultural waste composting.},
journal = {Bioresource technology},
volume = {270},
number = {},
pages = {278-285},
doi = {10.1016/j.biortech.2018.09.042},
pmid = {30223159},
issn = {1873-2976},
mesh = {Agriculture ; Ammonia/*metabolism ; Archaea/genetics/*metabolism ; *Composting ; Oxidation-Reduction ; Phylogeny ; Soil ; Soil Microbiology ; },
abstract = {In this research, the abundance and structure of AOA amoA gene during agricultural waste composting were determined by quantitative PCR and sequencing techniques, respectively. Pairwise correlations between potential ammonia oxidation (PAO) rate, physicochemical parameters and the AOA abundance were evaluated using Pearson correlation coefficient. Relationships between these parameters, PAO rates and AOA community structure were evaluated by redundancy analysis. Results showed that 22 AOA gene OTUs were divided into the soil/sediment lineage by phylogenetic analyses. Significant positive correlations were obtained between AOA amoA gene abundance and moisture, ammonium, water soluble carbon (WSC) and organic matter (OM), respectively. Redundancy analysis showed OM, pH and nitrate significantly explained the AOA amoA gene structure. Pearson correlation revealed the PAO rate correlated positively to ammonium, AOA amoA gene abundance. These results indicated that AOA communities sense the fluctuations in surrounding environment, and ultimately react and influence the nitrogen transformation during agricultural waste composting.},
}
@article {pmid30212260,
year = {2019},
author = {Santoro, AE and Richter, RA and Dupont, CL},
title = {Planktonic Marine Archaea.},
journal = {Annual review of marine science},
volume = {11},
number = {},
pages = {131-158},
doi = {10.1146/annurev-marine-121916-063141},
pmid = {30212260},
issn = {1941-0611},
abstract = {Archaea are ubiquitous and abundant members of the marine plankton. Once thought of as rare organisms found in exotic extremes of temperature, pressure, or salinity, archaea are now known in nearly every marine environment. Though frequently referred to collectively, the planktonic archaea actually comprise four major phylogenetic groups, each with its own distinct physiology and ecology. Only one group-the marine Thaumarchaeota-has cultivated representatives, making marine archaea an attractive focus point for the latest developments in cultivation-independent molecular methods. Here, we review the ecology, physiology, and biogeochemical impact of the four archaeal groups using recent insights from cultures and large-scale environmental sequencing studies. We highlight key gaps in our knowledge about the ecological roles of marine archaea in carbon flow and food web interactions. We emphasize the incredible uncultivated diversity within each of the four groups, suggesting there is much more to be done.},
}
@article {pmid30207323,
year = {2018},
author = {Patching, SG},
title = {Recent developments in nucleobase cation symporter-1 (NCS1) family transport proteins from bacteria, archaea, fungi and plants.},
journal = {Journal of biosciences},
volume = {43},
number = {4},
pages = {797-815},
pmid = {30207323},
issn = {0973-7138},
mesh = {Amino Acid Sequence/genetics ; Arabidopsis Proteins/*genetics ; Archaea/genetics ; Bacteria/genetics ; *Evolution, Molecular ; Fungi/genetics ; Microtubule-Associated Proteins/*genetics ; Nucleobase Transport Proteins/*genetics ; *Phylogeny ; Saccharomyces cerevisiae Proteins/*genetics ; Sequence Homology, Amino Acid ; Substrate Specificity ; },
abstract = {The nucleobase cation symporter-1 (NCS1) family of secondary active transport proteins comprises over 2500 sequenced members from bacteria, archaea, fungi and plants. NCS1 proteins use a proton or sodium gradient to drive inward cellular transport of purine and pyrimidine nucleobases and nucleosides, hydantoins and related compounds. The structural organization, substrate binding residues and molecular mechanism of NCS1 proteins are defined by crystal structures of sodium-coupled hydantoin transporter, Mhp1. Plant proteins are most closely related to bacterial/archaeal proteins and the distinct Fur-type and Fcy-type fungal proteins and plant proteins originated through independent horizontal transfers from prokaryotes. Analyses of 25 experimentally characterized proteins reveal high substrate specificity in bacterial proteins, distinct non-overlapping specificities in Fur-type and Fcy-type fungal proteins and broad specificity in plant proteins. Possible structural explanations are identified for differences in substrate specificity between bacterial proteins, whilst specificities of other proteins cannot be predicted by simple sequence comparisons. Specificity appears to be species specific and determined by combinations of effects dictated by multiple residues in the major substrate binding site and gating domains. This is an exploratory research review of evolutionary relationships, function and structural organization, molecular mechanism and origins of substrate specificity in NCS1 proteins and avenues of future direction.},
}
@article {pmid30199800,
year = {2018},
author = {Pan, KL and Gao, JF and Fan, XY and Li, DC and Dai, HH},
title = {The more important role of archaea than bacteria in nitrification of wastewater treatment plants in cold season despite their numerical relationships.},
journal = {Water research},
volume = {145},
number = {},
pages = {552-561},
doi = {10.1016/j.watres.2018.08.066},
pmid = {30199800},
issn = {1879-2448},
abstract = {Nitrification failure of wastewater treatment plants (WWTPs) in cold season calls into investigations of the functional ammonia-oxidizing microorganisms (AOMs). In this study, we report the abundance of ammonia-oxidizing archaea (AOA), bacteria (AOB) and complete ammonia-oxidizing (comammox) Nitrospira in 23 municipal WWTPs in cold season, and explore the correlations between AOMs abundance and their relative contribution to nitrification. The copy numbers of AOA and AOB amoA gene ranged from 2.42 × 107 to 2.47 × 109 and 5.54 × 106 to 3.31 × 109 copies/g sludge, respectively. The abundance of amoA gene of Candidatus Nitrospira inopinata, an important strain of comammox Nitrospira, was stable with averaged abundance of 8.47 × 106 copies/g sludge. DNA-based stable isotope probing (DNA-SIP) assays were conducted with three typical WWTPs in which the abundance of AOA was lower than, similar to and higher than that of AOB, respectively. The results showed that considerable 13C-assimilation by AOA was detected during active nitrification in all WWTPs, whereas just a much lesser extent of 13C-incorporation by AOB and comammox Nitrospira was found in one WWTP. High-throughput sequencing with 13C-labeled DNA also showed the higher reads abundance of AOA than AOB and comammox Nitrospira. Nitrososphaera viennensis was the dominant active AOA, while Nitrosomonas oligotropha and Nitrosomonas europaea were identified as active AOB. The results obtained suggest that AOA, rather than AOB and comammox Nitrospira, dominate ammonia oxidation in WWTPs in cold season despite the numerical relationships of AOMs.},
}
@article {pmid30194429,
year = {2019},
author = {Beulig, F and Røy, H and McGlynn, SE and Jørgensen, BB},
title = {Cryptic CH4 cycling in the sulfate-methane transition of marine sediments apparently mediated by ANME-1 archaea.},
journal = {The ISME journal},
volume = {13},
number = {2},
pages = {250-262},
doi = {10.1038/s41396-018-0273-z},
pmid = {30194429},
issn = {1751-7370},
mesh = {Archaea/genetics/*metabolism ; Carbon Dioxide/metabolism ; Geologic Sediments/*chemistry/*microbiology ; Metagenome ; Methane/analysis/*metabolism ; Oceans and Seas ; Oxidation-Reduction ; Sulfates/analysis/*metabolism ; },
abstract = {Methane in the seabed is mostly oxidized to CO2 with sulfate as the oxidant before it reaches the overlying water column. This microbial oxidation takes place within the sulfate-methane transition (SMT), a sediment horizon where the downward diffusive flux of sulfate encounters an upward flux of methane. Across multiple sites in the Baltic Sea, we identified a systematic discrepancy between the opposing fluxes, such that more sulfate was consumed than expected from the 1:1 stoichiometry of methane oxidation with sulfate. The flux discrepancy was consistent with an oxidation of buried organic matter within the SMT, as corroborated by stable carbon isotope budgets. Detailed radiotracer experiments showed that up to 60% of the organic matter oxidation within the SMT first produced methane, which was concurrently oxidized to CO2 by sulfate reduction. This previously unrecognized &quot;cryptic&quot; methane cycling in the SMT is not discernible from geochemical profiles due to overall net methane consumption. Sedimentary gene pools suggested that nearly all potential methanogens within and beneath the SMT belonged to ANME-1 archaea, which are typically associated with anaerobic methane oxidation. Analysis of a metagenome-assembled genome suggests that predominant ANME-1 do indeed have the enzymatic potential to catalyze both methane production and consumption.},
}
@article {pmid30186275,
year = {2018},
author = {Ghuneim, LJ and Jones, DL and Golyshin, PN and Golyshina, OV},
title = {Nano-Sized and Filterable Bacteria and Archaea: Biodiversity and Function.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {1971},
pmid = {30186275},
issn = {1664-302X},
abstract = {Nano-sized and filterable microorganisms are thought to represent the smallest living organisms on earth and are characterized by their small size (50-400 nm) and their ability to physically pass through <0.45 μm pore size filters. They appear to be ubiquitous in the biosphere and are present at high abundance across a diverse range of habitats including oceans, rivers, soils, and subterranean bedrock. Small-sized organisms are detected by culture-independent and culture-dependent approaches, with most remaining uncultured and uncharacterized at both metabolic and taxonomic levels. Consequently, their significance in ecological roles remain largely unknown. Successful isolation, however, has been achieved for some species (e.g., Nanoarchaeum equitans and &quot;Candidatus Pelagibacter ubique&quot;). In many instances, small-sized organisms exhibit a significant genome reduction and loss of essential metabolic pathways required for a free-living lifestyle, making their survival reliant on other microbial community members. In these cases, the nano-sized prokaryotes can only be co-cultured with their 'hosts.' This paper analyses the recent data on small-sized microorganisms in the context of their taxonomic diversity and potential functions in the environment.},
}
@article {pmid30175688,
year = {2018},
author = {Ten-Caten, F and Vêncio, RZN and Lorenzetti, APR and Zaramela, LS and Santana, AC and Koide, T},
title = {Internal RNAs overlapping coding sequences can drive the production of alternative proteins in archaea.},
journal = {RNA biology},
volume = {15},
number = {8},
pages = {1119-1132},
pmid = {30175688},
issn = {1555-8584},
mesh = {*Alternative Splicing ; Archaeal Proteins/genetics/*metabolism ; Base Sequence ; Gene Expression Profiling ; *Genome, Archaeal ; Halobacterium salinarum/genetics/growth &amp; development/*metabolism ; High-Throughput Nucleotide Sequencing ; *Open Reading Frames ; RNA, Antisense/*genetics ; RNA, Archaeal/*genetics ; Transcription Initiation Site ; },
abstract = {Prokaryotic genomes show a high level of information compaction often with different molecules transcribed from the same locus. Although antisense RNAs have been relatively well studied, RNAs in the same strand, internal RNAs (intraRNAs), are still poorly understood. The question of how common is the translation of overlapping reading frames remains open. We address this question in the model archaeon Halobacterium salinarum. In the present work we used differential RNA-seq (dRNA-seq) in H. salinarum NRC-1 to locate intraRNA signals in subsets of internal transcription start sites (iTSS) and establish the open reading frames associated to them (intraORFs). Using C-terminally flagged proteins, we experimentally observed isoforms accurately predicted by intraRNA translation for kef1, acs3 and orc4 genes. We also recovered from the literature and mass spectrometry databases several instances of protein isoforms consistent with intraRNA translation such as the gas vesicle protein gene gvpC1. We found evidence for intraRNAs in horizontally transferred genes such as the chaperone dnaK and the aerobic respiration related cydA in both H. salinarum and Escherichia coli. Also, intraRNA translation evidence in H. salinarum, E. coli and yeast of a universal elongation factor (aEF-2, fusA and eEF-2) suggests that this is an ancient phenomenon present in all domains of life.},
}
@article {pmid30172418,
year = {2018},
author = {Liu, Y and Liu, J and Yao, P and Ge, T and Qiao, Y and Zhao, M and Zhang, XH},
title = {Distribution patterns of ammonia-oxidizing archaea and bacteria in sediments of the eastern China marginal seas.},
journal = {Systematic and applied microbiology},
volume = {41},
number = {6},
pages = {658-668},
doi = {10.1016/j.syapm.2018.08.008},
pmid = {30172418},
issn = {1618-0984},
mesh = {Ammonia/*metabolism ; Archaea/*classification/isolation &amp; purification/metabolism ; Bacteria/*classification/isolation &amp; purification/metabolism ; Geologic Sediments/*microbiology ; Nitrification ; *Oceans and Seas ; Oxidation-Reduction ; Oxidoreductases ; Oxygen/chemistry ; Phylogeny ; Seawater/chemistry/microbiology ; },
abstract = {Ammonia-oxidizing archaea (AOA) and bacteria (AOB) vary in their contribution to nitrification in different environments. The eastern China marginal seas (ECMS) are featured by complex river runoffs and ocean currents, forming different sediment patches. Here, via quantitative PCR and clone library analysis of the amoA genes, we showed that AOB were more abundant than AOA in ECMS sediments. The abundance, diversity and richness of AOA, but not AOB, were higher in the East China Sea (ECS) than in the Yellow Sea (YS) and Bohai Sea (BS). Nitrosopumilus (AOA) and Nitrosospira (AOB) were predominant lineages, but their abundances varied significantly between ECS, and BS and YS. This was mainly attributed to salinity and dissolved oxygen of the bottom water. The discovery of a high abundance of Nitrosophaera at estuarine sites suggested strong terrigenous influence exerted on the AOA community. In contrast, variations in ocean conditions played more important roles in structuring the AOB community, which was separated by bottom water dissolved oxygen into two groups: the south YS, and the north YS and BS. This study provides a comprehensive insight into the spatial distribution pattern of ammonia-oxidizing prokaryotes in ECMS sediments, laying a foundation for understanding their relative roles in nitrification.},
}
@article {pmid30160784,
year = {2018},
author = {Borsodi, AK and Anda, D and Makk, J and Krett, G and Dobosy, P and Büki, G and Erőss, A and Mádl-Szőnyi, J},
title = {Biofilm forming bacteria and archaea in thermal karst springs of Gellért Hill discharge area (Hungary).},
journal = {Journal of basic microbiology},
volume = {58},
number = {11},
pages = {928-937},
doi = {10.1002/jobm.201800138},
pmid = {30160784},
issn = {1521-4028},
support = {NK101356//Hungarian Scientific Research Fund (NKFI)/ ; },
mesh = {Archaea/classification/genetics/*physiology/ultrastructure ; Bacteria, Thermoduric/classification/genetics/*physiology/ultrastructure ; Biodiversity ; *Biofilms ; Chemoautotrophic Growth ; DNA, Archaeal/genetics ; DNA, Bacterial/genetics ; Hot Springs/chemistry/*microbiology ; Hungary ; Microbial Consortia/genetics ; Microscopy, Electron, Scanning ; RNA, Ribosomal, 16S/genetics ; },
abstract = {The Buda Thermal Karst System (BTKS) is an extensive active hypogenic cave system located beneath the residential area of the Hungarian capital. At the river Danube, several thermal springs discharge forming spring caves. To reveal and compare the morphological structure and prokaryotic diversity of reddish-brown biofilms developed on the carbonate rock surfaces of the springs, scanning electron microscopy (SEM), and molecular cloning were applied. Microbial networks formed by filamentous bacteria and other cells with mineral crystals embedded in extracellular polymeric substances were observed in the SEM images. Biofilms were dominated by prokaryotes belonging to phyla Proteobacteria, Chloroflexi and Nitrospirae (Bacteria) and Thaumarchaeota (Archaea) but their abundance showed differences according to the type of the host rock, geographic distance, and different water exchange. In addition, representatives of phyla Acidobacteria, Actinobacteria, Caldithrix, Cyanobacteria, Firmicutes Gemmatimonadetes, and several candidate divisions of Bacteria as well as Crenarchaeota and Euryarchaeota were detected in sample-dependent higher abundance. The results indicate that thermophilic, anaerobic sulfur-, sulfate-, nitrate-, and iron(III)-reducing chemoorganotrophic as well as sulfur-, ammonia-, and nitrite-oxidizing chemolithotrophic prokaryotes can interact in the studied biofilms adapted to the unique and extreme circumstances (e.g., aphotic and nearly anoxic conditions, oligotrophy, and radionuclide accumulation) in the thermal karst springs.},
}
@article {pmid30158917,
year = {2018},
author = {Fournier, GP and Poole, AM},
title = {A Briefly Argued Case That Asgard Archaea Are Part of the Eukaryote Tree.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {1896},
pmid = {30158917},
issn = {1664-302X},
abstract = {The recent discovery of the Lokiarchaeota and other members of the Asgard superphylum suggests that closer analysis of the cell biology and evolution of these groups may help shed light on the origin of the eukaryote cell. Asgard lineages often appear in molecular phylogenies as closely related to eukaryotes, and possess &quot;Eukaryote Signature Proteins&quot; coded by genes previously thought to be unique to eukaryotes. This phylogenetic affinity to eukaryotes has been widely interpreted as indicating that Asgard lineages are &quot;eukaryote-like archaea,&quot; with eukaryotes evolving from within a paraphyletic Archaea. Guided by the established principles of systematics, we examine the potential implications of the monophyly of Asgard lineages and Eukarya. We show that a helpful parallel case is that of Synapsida, a group that includes modern mammals and their more &quot;reptile-like&quot; ancestors, united by shared derived characters that evolved in their common ancestor. While this group contains extinct members that share many similarities with modern reptiles and their extinct relatives, they are evolutionarily distinct from Sauropsida, the group which includes modern birds, reptiles, and all other amniotes. Similarly, Asgard lineages and eukaryotes are united by shared derived characters to the exclusion of all other groups. Consequently, the Asgard group is not only highly informative for our understanding of eukaryogenesis, but may be better understood as being early diverging members of a broader group including eukaryotes, for which we propose the name &quot;Eukaryomorpha.&quot; Significantly, this means that the relationship between Eukarya and Asgard lineages cannot, on its own, resolve the debate over 2 vs. 3 Domains of life; instead, resolving this debate depends upon identifying the root of Archaea with respect to Bacteria.},
}
@article {pmid30158542,
year = {2018},
author = {Cavazzini, D and Grossi, G and Levati, E and Vallese, F and Montanini, B and Bolchi, A and Zanotti, G and Ottonello, S},
title = {Author Correction: A family of archaea-like carboxylesterases preferentially expressed in the symbiotic phase of the mycorrhizal fungus Tuber melanosporum.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {13173},
doi = {10.1038/s41598-018-29606-0},
pmid = {30158542},
issn = {2045-2322},
abstract = {A correction to this article has been published and is linked from the HTML and the PDF versions of this paper. The error has been fixed in the paper.},
}
@article {pmid30142055,
year = {2018},
author = {Dulmage, KA and Darnell, CL and Vreugdenhil, A and Schmid, AK},
title = {Copy number variation is associated with gene expression change in archaea.},
journal = {Microbial genomics},
volume = {4},
number = {9},
pages = {},
pmid = {30142055},
issn = {2057-5858},
mesh = {Chromosome Breakpoints ; Chromosome Deletion ; Chromosomes, Archaeal ; *DNA Copy Number Variations ; Gene Expression Profiling ; Gene Expression Regulation ; Halobacterium salinarum/*genetics/metabolism ; Interspersed Repetitive Sequences ; Oligonucleotide Array Sequence Analysis ; Plasmids/genetics ; *Transcriptome ; Workflow ; },
abstract = {Genomic instability, although frequently deleterious, is also an important mechanism for microbial adaptation to environmental change. Although widely studied in bacteria, in archaea the effect of genomic instability on organism phenotypes and fitness remains unclear. Here we use DNA segmentation methods to detect and quantify genome-wide copy number variation (CNV) in large compendia of high-throughput datasets in a model archaeal species, Halobacterium salinarum. CNV hotspots were identified throughout the genome. Some hotspots were strongly associated with changes in gene expression, suggesting a mechanism for phenotypic innovation. In contrast, CNV hotspots in other genomic loci left expression unchanged, suggesting buffering of certain phenotypes. The correspondence of CNVs with gene expression was validated with strain- and condition-matched transcriptomics and DNA quantification experiments at specific loci. Significant correlation of CNV hotspot locations with the positions of known insertion sequence (IS) elements suggested a mechanism for generating genomic instability. Given the efficient recombination capabilities in H. salinarum despite stability at the single nucleotide level, these results suggest that genomic plasticity mediated by IS element activity can provide a source of phenotypic innovation in extreme environments.},
}
@article {pmid30137299,
year = {2018},
author = {Pohlschroder, M and Albers, SV},
title = {Editorial: Editorial for thematic issue on Archaea.},
journal = {FEMS microbiology reviews},
volume = {42},
number = {6},
pages = {719-720},
doi = {10.1093/femsre/fuy032},
pmid = {30137299},
issn = {1574-6976},
mesh = {Archaea/*physiology ; Archaeal Proteins/metabolism ; Environmental Microbiology ; Genome, Archaeal/genetics ; },
}
@article {pmid30116037,
year = {2019},
author = {Hoshino, T and Inagaki, F},
title = {Abundance and distribution of Archaea in the subseafloor sedimentary biosphere.},
journal = {The ISME journal},
volume = {13},
number = {1},
pages = {227-231},
doi = {10.1038/s41396-018-0253-3},
pmid = {30116037},
issn = {1751-7370},
mesh = {Archaea/*genetics/physiology ; Biomass ; DNA, Archaeal ; *Ecosystem ; Geologic Sediments/*microbiology ; Phylogeny ; Polymerase Chain Reaction ; RNA, Archaeal/genetics ; RNA, Ribosomal, 16S/genetics ; },
abstract = {Subseafloor sedimentary environments harbor a remarkable number of microorganisms that constitute anaerobic and aerobic microbial ecosystems beneath the ocean margins and open-ocean gyres, respectively. Microbial biomass and diversity richness generally decrease with increasing sediment depth and burial time. However, there has been a long-standing debate over the contribution and distribution of Archaea in the subseafloor sedimentary biosphere. Here we show the global quantification of archaeal and bacterial 16S rRNA genes in 221 sediment core samples obtained from diverse oceanographic settings through scientific ocean drilling using microfluidic digital PCR. We estimated that archaeal cells constitute 37.3% of the total microbial cells (40.0% and 12.8% in the ocean margin and open-ocean sites, respectively), corresponding to 1.1 × 1029 cells on Earth. In addition, the relative abundance of archaeal 16S rRNA genes generally decreased with the depth of water in the overlying sedimentary habitat, suggesting that Archaea may be more sensitive to nutrient quality and quantity supplied from the overlying ocean.},
}
@article {pmid30113887,
year = {2018},
author = {Grant, CR and Wan, J and Komeili, A},
title = {Organelle Formation in Bacteria and Archaea.},
journal = {Annual review of cell and developmental biology},
volume = {34},
number = {},
pages = {217-238},
doi = {10.1146/annurev-cellbio-100616-060908},
pmid = {30113887},
issn = {1530-8995},
support = {R01 GM084122/GM/NIGMS NIH HHS/United States ; R35 GM127114/GM/NIGMS NIH HHS/United States ; },
mesh = {Archaea/*genetics ; Bacteria/*genetics ; Cell Compartmentation/*genetics ; Cell Membrane/chemistry/genetics ; Lipids/chemistry/genetics ; Organelles/chemistry/*genetics ; },
abstract = {Uncovering the mechanisms that underlie the biogenesis and maintenance of eukaryotic organelles is a vibrant and essential area of biological research. In comparison, little attention has been paid to the process of compartmentalization in bacteria and archaea. This lack of attention is in part due to the common misconception that organelles are a unique evolutionary invention of the &quot;complex&quot; eukaryotic cell and are absent from the &quot;primitive&quot; bacterial and archaeal cells. Comparisons across the tree of life are further complicated by the nebulous criteria used to designate subcellular structures as organelles. Here, with the aid of a unified definition of a membrane-bounded organelle, we present some of the recent findings in the study of lipid-bounded organelles in bacteria and archaea.},
}
@article {pmid30105504,
year = {2019},
author = {Albright, MBN and Timalsina, B and Martiny, JBH and Dunbar, J},
title = {Comparative Genomics of Nitrogen Cycling Pathways in Bacteria and Archaea.},
journal = {Microbial ecology},
volume = {77},
number = {3},
pages = {597-606},
doi = {10.1007/s00248-018-1239-4},
pmid = {30105504},
issn = {1432-184X},
support = {F260LANL2018//U.S. Department of Energy, Office of Science, Biological and Environmental Research Division/ ; Graduate Student Research (SCGSR) Fellowship//U.S. Department of Energy, Office of Science/ ; },
mesh = {Archaea/*genetics/metabolism ; Archaeal Proteins/*genetics/metabolism ; Bacteria/*genetics/metabolism ; Bacterial Proteins/*genetics/metabolism ; Ecosystem ; Genome, Archaeal ; Genome, Bacterial ; Genomics ; Nitrogen/*metabolism ; Nitrogen Cycle ; },
abstract = {Despite the explosion of metagenomic sequencing data, using -omics data to predict environmental biogeochemistry remains a challenge. One or a few genes (referred to as marker genes) in a metabolic pathway of interest in meta-omic data are typically used to represent the prevalence of a biogeochemical reaction. This approach often fails to demonstrate a consistent relationship between gene abundance and an ecosystem process rate. One reason this may occur is if a marker gene is not a good representative of a complete pathway. Here, we map the presence of 11 nitrogen (N)-cycling pathways in over 6000 complete bacterial and archaeal genomes using the Integrated Microbial Genomes database. Incomplete N-cycling pathways occurred in 39% of surveyed archaeal and bacterial species revealing a weakness in current marker-gene analyses. Furthermore, we found that most organisms have limited ability to utilize inorganic N in multiple oxidation states. This suggests that inter-organism exchange of inorganic N compounds is common, highlighting the importance of both community composition and spatial structure in determining the extent of recycling versus loss in an ecosystem.},
}
@article {pmid30071063,
year = {2018},
author = {Gorlas, A and Jacquemot, P and Guigner, JM and Gill, S and Forterre, P and Guyot, F},
title = {Greigite nanocrystals produced by hyperthermophilic archaea of Thermococcales order.},
journal = {PloS one},
volume = {13},
number = {8},
pages = {e0201549},
pmid = {30071063},
issn = {1932-6203},
mesh = {Carbon Dioxide/chemistry ; Catalysis ; Ecosystem ; Hot Temperature ; Hydrothermal Vents ; Iron/*chemistry ; Microscopy, Electron, Transmission ; Nanoparticles/*chemistry/metabolism ; Oxidation-Reduction ; Spectrometry, X-Ray Emission ; Sulfides/*chemistry ; Thermococcales/*metabolism ; },
abstract = {Interactions between hyperthermophilic archaea and minerals occur in hydrothermal deep-sea vents, one of the most extreme environments for life on Earth. These interactions occur in the internal pores and at surfaces of active hydrothermal chimneys. In this study, we show that, at 85°C, Thermococcales, the predominant hyperthermophilic microorganisms inhabiting hot parts of hydrothermal deep-sea vents, produce greigite nanocrystals (Fe3S4) on extracellular polymeric substances, and that an amorphous iron phosphate acts as a precursor phase. Greigite, although a minor component of chimneys, is a recognized catalyst for CO2 reduction thus implying that Thermococcales may influence the balance of CO2 in hydrothermal ecosystems. We propose that observation of greigite nanocrystals on extracellular polymeric substances could provide a signature of hyperthermophilic life in hydrothermal deep-sea vents.},
}
@article {pmid30062501,
year = {2018},
author = {Karray, F and Ben Abdallah, M and Kallel, N and Hamza, M and Fakhfakh, M and Sayadi, S},
title = {Extracellular hydrolytic enzymes produced by halophilic bacteria and archaea isolated from hypersaline lake.},
journal = {Molecular biology reports},
volume = {45},
number = {5},
pages = {1297-1309},
pmid = {30062501},
issn = {1573-4978},
mesh = {Archaea/classification/*enzymology/isolation &amp; purification ; Bacteria/classification/*enzymology/isolation &amp; purification ; Biodiversity ; Classification/methods ; Enzymes/analysis/classification ; Halobacteriales/classification/*enzymology/isolation &amp; purification ; Lakes ; Phylogeny ; RNA, Ribosomal, 16S/genetics ; Salinity ; Sequence Analysis, DNA ; Tunisia ; Water Microbiology ; },
abstract = {The screening of bacteria and archaea from Chott El Jerid, a hypersaline lake in the south of Tunisia, led to the isolation of 68 extremely halophilic prokaryotes growing in media with 15-25% of salt. Assessment of 68 partial 16S rRNA analyzed by amplified rDNA restriction analysis (ARDRA) revealed 15 different bacterial and archaeal taxonomic groups. Based on ARDRA results, phenotypic and hydrolytic activity tests, 20 archaeal and 6 bacterial isolates were selected for sequencing. The halophilic isolates were identified as members of the genera: Salicola, Bacillus, Halorubrum, Natrinema and Haloterrigena. Most of these isolates are able to produce hydrolytic enzymes such as amylase, protease, lipase, cellulase, xylanase, pectinase and some of them showed combined activities. Natrinema genus is an excellent candidate for lipase production. These results indicated that the extremely halophilic archaea and bacteria from Chott El Jerid are a potential source of hydrolytic enzymes and may possess commercial value.},
}
@article {pmid30060184,
year = {2018},
author = {Narrowe, AB and Spang, A and Stairs, CW and Caceres, EF and Baker, BJ and Miller, CS and Ettema, TJG},
title = {Complex Evolutionary History of Translation Elongation Factor 2 and Diphthamide Biosynthesis in Archaea and Parabasalids.},
journal = {Genome biology and evolution},
volume = {10},
number = {9},
pages = {2380-2393},
pmid = {30060184},
issn = {1759-6653},
support = {310039//European Research Council/International ; },
mesh = {Archaea/*genetics/metabolism ; Biosynthetic Pathways ; Evolution, Molecular ; Genome, Archaeal ; Histidine/*analogs &amp; derivatives/genetics/metabolism ; Models, Molecular ; Parabasalidea/*genetics/metabolism ; Peptide Elongation Factor 2/*genetics/metabolism ; },
abstract = {Diphthamide is a modified histidine residue which is uniquely present in archaeal and eukaryotic elongation factor 2 (EF-2), an essential GTPase responsible for catalyzing the coordinated translocation of tRNA and mRNA through the ribosome. In part due to the role of diphthamide in maintaining translational fidelity, it was previously assumed that diphthamide biosynthesis genes (dph) are conserved across all eukaryotes and archaea. Here, comparative analysis of new and existing genomes reveals that some archaea (i.e., members of the Asgard superphylum, Geoarchaea, and Korarchaeota) and eukaryotes (i.e., parabasalids) lack dph. In addition, while EF-2 was thought to exist as a single copy in archaea, many of these dph-lacking archaeal genomes encode a second EF-2 paralog missing key residues required for diphthamide modification and for normal translocase function, perhaps suggesting functional divergence linked to loss of diphthamide biosynthesis. Interestingly, some Heimdallarchaeota previously suggested to be most closely related to the eukaryotic ancestor maintain dph genes and a single gene encoding canonical EF-2. Our findings reveal that the ability to produce diphthamide, once thought to be a universal feature in archaea and eukaryotes, has been lost multiple times during evolution, and suggest that anticipated compensatory mechanisms evolved independently.},
}
@article {pmid30054090,
year = {2019},
author = {Ma, M and Du, H and Sun, T and An, S and Yang, G and Wang, D},
title = {Characteristics of archaea and bacteria in rice rhizosphere along a mercury gradient.},
journal = {The Science of the total environment},
volume = {650},
number = {Pt 1},
pages = {1640-1651},
doi = {10.1016/j.scitotenv.2018.07.175},
pmid = {30054090},
issn = {1879-1026},
mesh = {*Archaea/classification/genetics ; *Bacteria/classification/genetics ; Biodiversity ; China ; *Environmental Monitoring ; Mercury/*analysis ; Methylmercury Compounds/analysis ; Mining ; Oryza/*microbiology ; RNA, Ribosomal, 16S/genetics ; *Rhizosphere ; Soil/chemistry ; *Soil Microbiology ; Soil Pollutants/analysis ; },
abstract = {Several strains of archaea have the ability to methylate or resist mercury (Hg), and the paddy field is regarded to be conducive to Hg methylation. However, our knowledge of Hg-methylating or Hg-resistant archaea in paddy soils is very limited so far. Therefore, the distribution of archaea and bacteria in the rhizosphere (RS) and bulk soil (BS) of the rice growing in Xiushan Hg-mining area of southwest China was investigated. Bacterial and archaeal 16S rRNA gene amplicon sequencing of the rice rhizosphere along the Hg gradient was conducted. THg concentrations in RS were significantly higher than that in BS at site S1 and S2, while MeHg concentrations in RS was always higher than that in BS, except S6. Bacterial species richness estimates were much higher than that in archaea. The bacterial α-diversity in high-Hg sites was significant higher than that in low-Hg sites based on ACE and Shannon indices. At the genus level, Thiobacillus, Xanthomonas, Defluviicoccus and Candidatus Nitrosoarchaeum were significantly more abundant in the rhizosphere of high-Hg sites, which meant that strains in these genera might play important roles in response to Hg stress. Hg-methylating archaea in the paddy field could potentially be affiliated to strains in Methanosarcina, but further evidence need to be found. The results provide reference to understand archaeal rhizosphere community along an Hg gradient paddy soils.},
}
@article {pmid30053578,
year = {2018},
author = {Smith-Moore, CM and Grunden, AM},
title = {Bacteria and archaea as the sources of traits for enhanced plant phenotypes.},
journal = {Biotechnology advances},
volume = {36},
number = {7},
pages = {1900-1916},
doi = {10.1016/j.biotechadv.2018.07.007},
pmid = {30053578},
issn = {1873-1899},
mesh = {Archaea/*genetics ; Bacteria/*genetics ; Carbon Cycle ; *Genetic Engineering ; Nitrogen/metabolism ; Phenotype ; Phosphates/metabolism ; Photosynthesis ; *Plant Development ; *Plant Physiological Phenomena ; Plants/genetics/*microbiology ; Plants, Genetically Modified ; Stress, Physiological ; },
abstract = {Rising global demand for food and population increases are driving the need for improved crop productivity over the next 30 years. Plants have inherent metabolic limitations on productivity such as inefficiencies in carbon fixation and sensitivity to environmental conditions. Bacteria and archaea inhabit some of the most inhospitable environments on the planet and possess unique metabolic pathways and genes to cope with these conditions. Microbial genes involved in carbon fixation, abiotic stress tolerance, and nutrient acquisition have been utilized in plants to enhance plant phenotypes by increasing yield, photosynthesis, and abiotic stress tolerance. Transgenic plants expressing bacterial and archaeal genes will be discussed along with emerging strategies and tools to increase plant growth and yield.},
}
@article {pmid30050524,
year = {2018},
author = {Kashyap, S and Sklute, EC and Dyar, MD and Holden, JF},
title = {Reduction and Morphological Transformation of Synthetic Nanophase Iron Oxide Minerals by Hyperthermophilic Archaea.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {1550},
pmid = {30050524},
issn = {1664-302X},
abstract = {Fe(III) (oxyhydr)oxides are electron acceptors for some hyperthermophilic archaea in mildly reducing geothermal environments. However, the kinds of iron oxides that can be used, growth rates, extent of iron reduction, and the morphological changes that occur to minerals are poorly understood. The hyperthermophilic iron-reducing crenarchaea Pyrodictium delaneyi and Pyrobaculum islandicum were grown separately on six different synthetic nanophase Fe(III) (oxyhydr)oxides. For both organisms, growth on ferrihydrite produced the highest growth rates and the largest amounts of Fe(II), although P. delaneyi produced four times more Fe(II) (25 mM) than P. islandicum (6 mM). Both organisms grew on lepidocrocite and akaganéite and produced 2 and 3 mM Fe(II). Modest growth occurred for both organisms on goethite, hematite, and maghemite where ≤1 mM Fe(II) was produced. The diameters of the spherical mineral end-products following P. delaneyi growth increased by 30 nm for ferrihydrite and 50-150 nm for lepidocrocite relative to heated abiotic controls. For akaganéite, spherical particle sizes were the same for P. delaneyi-reacted samples and heated abiotic controls, but the spherical particles were more numerous in the P. delaneyi samples. For P. islandicum, there was no increase in grain size for the mineral end-products following growth on ferrihydrite, lepidocrocite, or akaganéite relative to the heated abiotic controls. High-resolution transmission electron microscopy of lattice fringes and selected-area electron diffraction of the minerals produced by both organisms when grown on ferrihydrite showed that magnetite and/or possibly maghemite were the end-products while the heated abiotic controls only contained ferrihydrite. These results expand the current view of bioavailable Fe(III) (oxyhydr)oxides for reduction by hyperthermophilic archaea when presented as synthetic nanophase minerals. They show that growth and reduction rates are inversely correlated with the iron (oxyhydr)oxide crystallinity and that iron (oxyhydr)oxide mineral transformation takes different forms for these two organisms.},
}
@article {pmid30022612,
year = {2018},
author = {Heal, KR and Qin, W and Amin, SA and Devol, AH and Moffett, JW and Armbrust, EV and Stahl, DA and Ingalls, AE},
title = {Accumulation of NO2 -cobalamin in nutrient-stressed ammonia-oxidizing archaea and in the oxygen deficient zone of the eastern tropical North Pacific.},
journal = {Environmental microbiology reports},
volume = {10},
number = {4},
pages = {453-457},
doi = {10.1111/1758-2229.12664},
pmid = {30022612},
issn = {1758-2229},
mesh = {Ammonia/metabolism ; Archaea/*metabolism/physiology ; Bioreactors ; Copper/deficiency/metabolism ; Hypoxia ; Oxidation-Reduction ; Pacific Ocean ; Seawater/*chemistry ; *Stress, Physiological ; Tropical Climate ; Vitamin B 12/*analogs &amp; derivatives/analysis/chemistry/metabolism ; },
abstract = {Cobalamin (vitamin B12) is a precious resource in natural systems that is produced by select prokaryotes and required by a broad range of organisms. In this way, the production of cobalamin reinforces numerous microbial interdependencies. Here we report the accumulation of an unusual form of cobalamin, nitrocobalamin (NO2 -cobalamin), in a marine oxygen deficient zone (ODZ), isolates of ammonia-oxidizing archaea (AOA), and an anaerobic ammonium-oxidizing (anammox) bacteria enriched bioreactor. Low oxygen waters were enriched in NO2 -cobalamin, and AOA isolates experiencing ammonia or copper stress produced more NO2 -cobalamin, though there is wide strain-to-strain and batch-to-batch variability. NO2 -cobalamin has no known biochemical role. We hypothesize that AOA and anammox bacteria are a source of marine NO2 -cobalamin in the environment via a reactive nitrogen intermediate. These findings suggest connections between cobalamin forms and nitrogen transformations, physiological stress and ocean deoxygenation.},
}
@article {pmid30016225,
year = {2018},
author = {Aiewsakun, P and Adriaenssens, EM and Lavigne, R and Kropinski, AM and Simmonds, P},
title = {Evaluation of the genomic diversity of viruses infecting bacteria, archaea and eukaryotes using a common bioinformatic platform: steps towards a unified taxonomy.},
journal = {The Journal of general virology},
volume = {99},
number = {9},
pages = {1331-1343},
pmid = {30016225},
issn = {1465-2099},
support = {//Wellcome Trust/United Kingdom ; WT108418AIA//Wellcome Trust/United Kingdom ; },
mesh = {Archaea/virology ; Archaeal Viruses/*genetics ; Bacteria/virology ; Bacteriophages/*genetics ; Computational Biology/*methods ; Eukaryota/virology ; Genes, Viral ; *Genetic Variation ; *Genome, Viral ; Genomics ; Metagenomics ; Phylogeny ; Viruses/genetics ; },
abstract = {Genome Relationship Applied to Virus Taxonomy (GRAViTy) is a genetics-based tool that computes sequence relatedness between viruses. Composite generalized Jaccard (CGJ) distances combine measures of homology between encoded viral genes and similarities in genome organizational features (gene orders and orientations). This scoring framework effectively recapitulates the current, largely morphology and phenotypic-based, family-level classification of eukaryotic viruses. Eukaryotic virus families typically formed monophyletic groups with consistent CGJ distance cut-off dividing between and within family divergence ranges. In the current study, a parallel analysis of prokaryotic virus families revealed quite different sequence relationships, particularly those of tailed phage families (Siphoviridae, Myoviridae and Podoviridae), where members of the same family were generally far more divergent and often not detectably homologous to each other. Analysis of the 20 currently classified prokaryotic virus families indeed split them into 70 separate clusters of tailed phages genetically equivalent to family-level assignments of eukaryotic viruses. It further divided several bacterial (Sphaerolipoviridae, Tectiviridae) and archaeal (Lipothrixviridae) families. We also found that the subfamily-level groupings of tailed phages were generally more consistent with the family assignments of eukaryotic viruses, and this supports ongoing reclassifications, including Spounavirinae and Vi1virus taxa as new virus families. The current study applied a common benchmark with which to compare taxonomies of eukaryotic and prokaryotic viruses. The findings support the planned shift away from traditional morphology-based classifications of prokaryotic viruses towards a genome-based taxonomy. They demonstrate the feasibility of a unified taxonomy of viruses into which the vast body of metagenomic viral sequences may be consistently assigned.},
}
@article {pmid30010922,
year = {2018},
author = {van Tran, N and Muller, L and Ross, RL and Lestini, R and Létoquart, J and Ulryck, N and Limbach, PA and de Crécy-Lagard, V and Cianférani, S and Graille, M},
title = {Evolutionary insights into Trm112-methyltransferase holoenzymes involved in translation between archaea and eukaryotes.},
journal = {Nucleic acids research},
volume = {46},
number = {16},
pages = {8483-8499},
pmid = {30010922},
issn = {1362-4962},
support = {R01 GM070641/GM/NIGMS NIH HHS/United States ; R01 GM058843/GM/NIGMS NIH HHS/United States ; },
mesh = {Archaeal Proteins/*physiology ; Bacterial Proteins/genetics/*physiology ; Crystallography, X-Ray ; Datasets as Topic ; Enzyme Activation ; Eukaryotic Cells/enzymology ; Evolution, Molecular ; Haloferax volcanii/*enzymology ; Holoenzymes/physiology ; Immunoprecipitation ; Mass Spectrometry ; Methylation ; Models, Molecular ; Protein Binding ; Protein Conformation ; Protein Interaction Mapping ; Proteomics ; *RNA Processing, Post-Transcriptional ; Recombinant Proteins/metabolism ; Sequence Alignment ; Species Specificity ; tRNA Methyltransferases/deficiency/genetics/*physiology ; },
abstract = {Protein synthesis is a complex and highly coordinated process requiring many different protein factors as well as various types of nucleic acids. All translation machinery components require multiple maturation events to be functional. These include post-transcriptional and post-translational modification steps and methylations are the most frequent among these events. In eukaryotes, Trm112, a small protein (COG2835) conserved in all three domains of life, interacts and activates four methyltransferases (Bud23, Trm9, Trm11 and Mtq2) that target different components of the translation machinery (rRNA, tRNAs, release factors). To clarify the function of Trm112 in archaea, we have characterized functionally and structurally its interaction network using Haloferax volcanii as model system. This led us to unravel that methyltransferases are also privileged Trm112 partners in archaea and that this Trm112 network is much more complex than anticipated from eukaryotic studies. Interestingly, among the identified enzymes, some are functionally orthologous to eukaryotic Trm112 partners, emphasizing again the similarity between eukaryotic and archaeal translation machineries. Other partners display some similarities with bacterial methyltransferases, suggesting that Trm112 is a general partner for methyltransferases in all living organisms.},
}
@article {pmid30003649,
year = {2018},
author = {Aalto, SL and Saarenheimo, J and Mikkonen, A and Rissanen, AJ and Tiirola, M},
title = {Resistant ammonia-oxidizing archaea endure, but adapting ammonia-oxidizing bacteria thrive in boreal lake sediments receiving nutrient-rich effluents.},
journal = {Environmental microbiology},
volume = {20},
number = {10},
pages = {3616-3628},
pmid = {30003649},
issn = {1462-2920},
support = {286642310302//Biotieteiden ja Ympäristön Tutkimuksen Toimikunta/International ; LIFE12 ENV/FI/597 (N-SINK)//European Commission/International ; 615146//European Research Council/International ; 286642//Academy of Finland/International ; 310302//Academy of Finland/International ; 260797//Academy of Finland/International ; },
abstract = {Climate change along with anthropogenic activities changes biogeochemical conditions in lake ecosystems, modifying the sediment microbial communities. Wastewater effluents introduce nutrients and organic material but also novel microbes to lake ecosystems, simulating forthcoming increases in catchment loadings. In this work, we first used 16s rRNA gene sequencing to study how the overall sediment microbial community responds to wastewater in six boreal lakes. To examine forthcoming changes in the lake biogeochemistry, we focused on the ammonia-oxidizing archaea (AOA) and bacteria (AOB), and examined their functional and compositional community response to wastewater. Although we found the least diverse and least resistant prokaryotic communities from the most wastewater-influenced sediments, the community changed fast toward the natural composition with the diminishing influence of wastewater. Each lake hosted a unique resistant AOA community, while AOB communities were adapting, responding to environmental conditions as well as receiving new members from WWTPs. In general, AOB dominated in numbers in wastewater-influenced sediments, while the ratio between AOA and AOB increased when moving toward pristine conditions. Our results suggest that although future climate-change-driven increases in nutrient loading and microbial migration might significantly disrupt lake sediment microbiomes, they can promote nitrification through adapting and abundant AOB communities.},
}
@article {pmid29979671,
year = {2018},
author = {Bowers, RM and Kyrpides, NC and Stepanauskas, R and Harmon-Smith, M and Doud, D and Reddy, TBK and Schulz, F and Jarett, J and Rivers, AR and Eloe-Fadrosh, EA and Tringe, SG and Ivanova, NN and Copeland, A and Clum, A and Becraft, ED and Malmstrom, RR and Birren, B and Podar, M and Bork, P and Weinstock, GM and Garrity, GM and Dodsworth, JA and Yooseph, S and Sutton, G and Glöckner, FO and Gilbert, JA and Nelson, WC and Hallam, SJ and Jungbluth, SP and Ettema, TJG and Tighe, S and Konstantinidis, KT and Liu, WT and Baker, BJ and Rattei, T and Eisen, JA and Hedlund, B and McMahon, KD and Fierer, N and Knight, R and Finn, R and Cochrane, G and Karsch-Mizrachi, I and Tyson, GW and Rinke, C and , and Lapidus, A and Meyer, F and Yilmaz, P and Parks, DH and Eren, AM and Schriml, L and Banfield, JF and Hugenholtz, P and Woyke, T},
title = {Corrigendum: Minimum information about a single amplified genome (MISAG) and a metagenome-assembled genome (MIMAG) of bacteria and archaea.},
journal = {Nature biotechnology},
volume = {36},
number = {7},
pages = {660},
pmid = {29979671},
issn = {1546-1696},
}
@article {pmid29978909,
year = {2019},
author = {Yip, DZ and Veach, AM and Yang, ZK and Cregger, MA and Schadt, CW},
title = {Methanogenic Archaea dominate mature heartwood habitats of Eastern Cottonwood (Populus deltoides).},
journal = {The New phytologist},
volume = {222},
number = {1},
pages = {115-121},
doi = {10.1111/nph.15346},
pmid = {29978909},
issn = {1469-8137},
support = {DEAC05-00OR22725//US Department of Energy/ ; //Office of Science/ ; //Biological and Environmental Research/ ; },
abstract = {While recent reports demonstrate that the direct emission of methane from living tree trunks may be a significant terrestrial emission source, there has been debate whether tree emissions are due to transport from soils or produced in the wood environment itself. Reports of methanogens from wood of trees were prominent in the literature 40 years ago but have not been revisited with molecular ecology approaches. We examined communities associated with Populus deltoides using rRNA gene sequence analyses and how these vary with tree and wood properties. Our data indicate that wood environments are dominated by anaerobic microbiomes. Methanogens are prominent in heartwood (mean 34% relative abundance) compared to sapwood environments (13%), and dominant operational taxonomic units (OTUs) were classified as the Methanobacterium sp. Members of the Firmicutes phylum comprised 39% of total sequences and were in 42% greater abundance in sapwood over heartwood niches. Tree diameter was the strongest predictor of methanogen abundance, but wood moisture content and pH were also significant predictors of taxon abundance and overall community composition. Unlike microbiomes of the soil, rhizosphere and phyllosphere, wood associated communities are shaped by unique environmental conditions and may be prominent and overlooked sources of methane emissions in temperate forest systems.},
}
@article {pmid29978046,
year = {2018},
author = {Karimi, B and Terrat, S and Dequiedt, S and Saby, NPA and Horrigue, W and Lelièvre, M and Nowak, V and Jolivet, C and Arrouays, D and Wincker, P and Cruaud, C and Bispo, A and Maron, PA and Bouré, NCP and Ranjard, L},
title = {Biogeography of soil bacteria and archaea across France.},
journal = {Science advances},
volume = {4},
number = {7},
pages = {eaat1808},
pmid = {29978046},
issn = {2375-2548},
abstract = {Over the last two decades, a considerable effort has been made to decipher the biogeography of soil microbial communities as a whole, from small to broad scales. In contrast, few studies have focused on the taxonomic groups constituting these communities; thus, our knowledge of their ecological attributes and the drivers determining their composition and distribution is limited. We applied a pyrosequencing approach targeting 16S ribosomal RNA (rRNA) genes in soil DNA to a set of 2173 soil samples from France to reach a comprehensive understanding of the spatial distribution of bacteria and archaea and to identify the ecological processes and environmental drivers involved. Taxonomic assignment of the soil 16S rRNA sequences indicated the presence of 32 bacterial phyla or subphyla and 3 archaeal phyla. Twenty of these 35 phyla were cosmopolitan and abundant, with heterogeneous spatial distributions structured in patches ranging from a 43- to 260-km radius. The hierarchy of the main environmental drivers of phyla distribution was soil pH > land management > soil texture > soil nutrients > climate. At a lower taxonomic level, 47 dominant genera belonging to 12 phyla aggregated 62.1% of the sequences. We also showed that the phylum-level distribution can be determined largely by the distribution of the dominant genus or, alternatively, reflect the combined distribution of all of the phylum members. Together, our study demonstrated that soil bacteria and archaea present highly diverse biogeographical patterns on a nationwide scale and that studies based on intensive and systematic sampling on a wide spatial scale provide a promising contribution for elucidating soil biodiversity determinism.},
}
@article {pmid29946801,
year = {2018},
author = {Li, F and Xie, W and Yuan, Q and Luo, H and Li, P and Chen, T and Zhao, X and Wang, Z and Ma, H},
title = {Genome-scale metabolic model analysis indicates low energy production efficiency in marine ammonia-oxidizing archaea.},
journal = {AMB Express},
volume = {8},
number = {1},
pages = {106},
pmid = {29946801},
issn = {2191-0855},
support = {2015CB755704//National Key Basic Research Program of China/ ; 16YFXTsf00460//Major Research Plan of Tianjin/ ; 21390201//National Natural Science Foundation of China/ ; 21621004//National Natural Science Foundation of China/ ; 91428308//National Natural Science Foundation of China/ ; ZDRW-ZS-2016-3//Key Research Program of the Chinese Academy of Sciences/ ; 41306123//National Science Foundation for Young Scholars of China/ ; 2016YFA0601101//the State Key R&amp;D project of China/ ; },
abstract = {Marine ammonia-oxidizing archaea (AOA) play an important role in the global nitrogen cycle by obtaining energy for biomass production from CO2 via oxidation of ammonium. The isolation of Candidatus &quot;Nitrosopumilus maritimus&quot; strain SCM1, which represents the globally distributed AOA in the ocean, provided an opportunity for uncovering the contributions of those AOA to carbon and nitrogen cycles in ocean. Although several ammonia oxidation pathways have been proposed for SCM1, little is known about its ATP production efficiency. Here, based on the published genome of Nitrosopumilus maritimus SCM1, a genome-scale metabolic model named NmrFL413 was reconstructed. Based on the model NmrFL413, the estimated ATP/NH4+ yield (0.149-0.276 ATP/NH4+) is tenfold lower than the calculated theoretical yield of the proposed ammonia oxidation pathways in marine AOA (1.5-1.75 ATP/NH4+), indicating a low energy production efficiency of SCM1. Our model also suggested the minor contribution of marine AOA to carbon cycle comparing with their significant contribution to nitrogen cycle in the ocean.},
}
@article {pmid29945179,
year = {2018},
author = {Straub, CT and Counts, JA and Nguyen, DMN and Wu, CH and Zeldes, BM and Crosby, JR and Conway, JM and Otten, JK and Lipscomb, GL and Schut, GJ and Adams, MWW and Kelly, RM},
title = {Biotechnology of extremely thermophilic archaea.},
journal = {FEMS microbiology reviews},
volume = {42},
number = {5},
pages = {543-578},
doi = {10.1093/femsre/fuy012},
pmid = {29945179},
issn = {1574-6976},
support = {T32 GM008776/GM/NIGMS NIH HHS/United States ; },
mesh = {Archaea/genetics/*physiology ; Biotechnology/*trends ; *Hot Temperature ; Industrial Microbiology/trends ; Metabolic Engineering/*trends ; },
abstract = {Although the extremely thermophilic archaea (Topt ≥ 70°C) may be the most primitive extant forms of life, they have been studied to a limited extent relative to mesophilic microorganisms. Many of these organisms have unique biochemical and physiological characteristics with important biotechnological implications. These include methanogens that generate methane, fermentative anaerobes that produce hydrogen gas with high efficiency, and acidophiles that can mobilize base, precious and strategic metals from mineral ores. Extremely thermophilic archaea have also been a valuable source of thermoactive, thermostable biocatalysts, but their use as cellular systems has been limited because of the general lack of facile genetics tools. This situation has changed recently, however, thereby providing an important avenue for understanding their metabolic and physiological details and also opening up opportunities for metabolic engineering efforts. Along these lines, extremely thermophilic archaea have recently been engineered to produce a variety of alcohols and industrial chemicals, in some cases incorporating CO2 into the final product. There are barriers and challenges to these organisms reaching their full potential as industrial microorganisms but, if these can be overcome, a new dimension for biotechnology will be forthcoming that strategically exploits biology at high temperatures.},
}
@article {pmid29944192,
year = {2018},
author = {Staley, JT and Caetano-Anollés, G},
title = {Archaea-First and the Co-Evolutionary Diversification of Domains of Life.},
journal = {BioEssays : news and reviews in molecular, cellular and developmental biology},
volume = {40},
number = {8},
pages = {e1800036},
doi = {10.1002/bies.201800036},
pmid = {29944192},
issn = {1521-1878},
mesh = {Archaea/genetics/*physiology ; Archaeal Proteins/chemistry/genetics/metabolism ; Bacteria/cytology/genetics ; *Biological Evolution ; Cell Membrane/metabolism ; Cell Wall/chemistry/metabolism ; Eukaryota/cytology/genetics/*physiology ; Gene Transfer, Horizontal ; Genomics ; Methane/metabolism ; Phospholipids/metabolism ; Phylogeny ; Proteome ; },
abstract = {The origins and evolution of the Archaea, Bacteria, and Eukarya remain controversial. Phylogenomic-wide studies of molecular features that are evolutionarily conserved, such as protein structural domains, suggest Archaea is the first domain of life to diversify from a stem line of descent. This line embodies the last universal common ancestor of cellular life. Here, we propose that ancestors of Euryarchaeota co-evolved with those of Bacteria prior to the diversification of Eukarya. This co-evolutionary scenario is supported by comparative genomic and phylogenomic analyses of the distributions of fold families of domains in the proteomes of free-living organisms, which show horizontal gene recruitments and informational process homologies. It also benefits from the molecular study of cell physiologies responsible for membrane phospholipids, methanogenesis, methane oxidation, cell division, gas vesicles, and the cell wall. Our theory however challenges popular cell fusion and two-domain of life scenarios derived from sequence analysis, demanding phylogenetic reconciliation. Also see the video abstract here: https://youtu.be/9yVWn_Q9faY.},
}
@article {pmid29930548,
year = {2018},
author = {Wu, Y and Wu, P and Wang, B and Shao, ZQ},
title = {Genome-Wide Analysis Reveals Ancestral Lack of Seventeen Different tRNAs and Clade-Specific Loss of tRNA-CNNs in Archaea.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {1245},
pmid = {29930548},
issn = {1664-302X},
abstract = {Transfer RNA (tRNA) is a category of RNAs that specifically decode messenger RNAs (mRNAs) into proteins by recognizing a set of 61 codons commonly adopted by different life domains. The composition and abundance of tRNAs play critical roles in shaping codon usage and pairing bias, which subsequently modulate mRNA translation efficiency and accuracy. Over the past few decades, effort has been concentrated on evaluating the specificity and redundancy of different tRNA families. However, the mechanism and processes underlying tRNA evolution have only rarely been investigated. In this study, by surveying tRNA genes in 167 completely sequenced genomes, we systematically investigated the composition and evolution of tRNAs in Archaea from a phylogenetic perspective. Our data revealed that archaeal genomes are compact in both tRNA types and copy number. Generally, no more than 44 different types of tRNA are present in archaeal genomes to decode the 61 canonical codons, and most of them have only one gene copy per genome. Among them, tRNA-Met was significantly overrepresented, with an average of three copies per genome. In contrast, the tRNA-UAU and 16 tRNAs with A-starting anticodons (tRNA-ANNs) were rarely detected in all archaeal genomes. The conspicuous absence of these tRNAs across the archaeal phylogeny suggests they might have not been evolved in the common ancestor of Archaea, rather than have lost independently from different clades. Furthermore, widespread absence of tRNA-CNNs in the Methanococcales and Methanobacteriales genomes indicates convergent loss of these tRNAs in the two clades. This clade-specific tRNA loss may be attributing to the reductive evolution of their genomes. Our data suggest that the current tRNA profiles in Archaea are contributed not only by the ancestral tRNA composition, but also by differential maintenance and loss of redundant tRNAs.},
}
@article {pmid29916347,
year = {2018},
author = {Höfer, K and Jäschke, A},
title = {Epitranscriptomics: RNA Modifications in Bacteria and Archaea.},
journal = {Microbiology spectrum},
volume = {6},
number = {3},
pages = {},
doi = {10.1128/microbiolspec.RWR-0015-2017},
pmid = {29916347},
issn = {2165-0497},
mesh = {Archaea/*genetics/metabolism ; Bacteria/*genetics/metabolism ; Epigenesis, Genetic ; RNA Processing, Post-Transcriptional ; RNA Stability ; RNA, Archaeal/chemistry/*genetics/metabolism ; RNA, Bacterial/chemistry/*genetics/metabolism ; RNA, Transfer/chemistry/genetics/metabolism ; Transcriptome ; },
abstract = {The increasingly complex functionality of RNA is contrasted by its simple chemical composition. RNA is generally built from only four different nucleotides (adenine, guanine, cytosine, and uracil). To date, >160 chemical modifications are known to decorate RNA molecules and thereby alter their function or stability. Many RNA modifications are conserved throughout bacteria, archaea, and eukaryotes, while some are unique to each branch of life. Most known modifications occur at internal positions, while there is limited diversity at the termini. The dynamic nature of RNA modifications and newly discovered regulatory functions of some of these RNA modifications gave birth to a new field, now often referred to as &quot;epitranscriptomics.&quot; This review highlights the major developments in this field and summarizes detection principles for internal as well as 5'-terminal mRNA modifications in prokaryotes and archaea to investigate their biological significance.},
}
@article {pmid29909833,
year = {2018},
author = {Ulrich, EC and Kamat, SS and Hove-Jensen, B and Zechel, DL},
title = {Methylphosphonic Acid Biosynthesis and Catabolism in Pelagic Archaea and Bacteria.},
journal = {Methods in enzymology},
volume = {605},
number = {},
pages = {351-426},
doi = {10.1016/bs.mie.2018.01.039},
pmid = {29909833},
issn = {1557-7988},
support = {P01 GM077596/GM/NIGMS NIH HHS/United States ; },
mesh = {Aquatic Organisms/*metabolism ; Archaea/*metabolism ; Archaeal Proteins/metabolism ; Bacteria/*metabolism ; Bacterial Proteins/metabolism ; Lyases/metabolism ; Methane/metabolism ; Oceans and Seas ; Organophosphorus Compounds/*metabolism ; Oxygenases/metabolism ; Phosphates/metabolism ; Seawater/microbiology ; },
abstract = {Inorganic phosphate is essential for all life forms, yet microbes in marine environments are in near constant deprivation of this important nutrient. Organophosphonic acids can serve as an alternative source of inorganic phosphate if microbes possess the appropriate biochemical pathways that allow cleavage of the stable carbon-phosphorus bond that defines this class of molecule. One prominent source of inorganic phosphate is methylphosphonic acid, which is found as a constituent of marine-dissolved organic matter. The cycle of biosynthesis and catabolism of methylphosphonic acid by marine microbes is the likely source of supersaturating levels of methane in shallow ocean waters. This review provides an overview of the rich biochemistry that has evolved to synthesize methylphosphonic acid and catabolize this molecule into Pi and methane, with an emphasis on the reactions catalyzed by methylphosphonic acid synthase MpnS and the carbon-phosphorus lyase system. The protocols and experiments that are described for MpnS and carbon-phosphorus lyase provide a foundation for studying the structures and mechanisms of these and related enzymes.},
}
@article {pmid29905870,
year = {2018},
author = {Rodriguez-R, LM and Gunturu, S and Harvey, WT and Rosselló-Mora, R and Tiedje, JM and Cole, JR and Konstantinidis, KT},
title = {The Microbial Genomes Atlas (MiGA) webserver: taxonomic and gene diversity analysis of Archaea and Bacteria at the whole genome level.},
journal = {Nucleic acids research},
volume = {46},
number = {W1},
pages = {W282-W288},
pmid = {29905870},
issn = {1362-4962},
mesh = {Classification ; Genetic Variation/genetics ; Genome, Archaeal/genetics ; Genome, Bacterial/genetics ; *Genomics ; *Internet ; Phylogeny ; RNA, Ribosomal, 16S/*genetics ; *Software ; },
abstract = {The small subunit ribosomal RNA gene (16S rRNA) has been successfully used to catalogue and study the diversity of prokaryotic species and communities but it offers limited resolution at the species and finer levels, and cannot represent the whole-genome diversity and fluidity. To overcome these limitations, we introduced the Microbial Genomes Atlas (MiGA), a webserver that allows the classification of an unknown query genomic sequence, complete or partial, against all taxonomically classified taxa with available genome sequences, as well as comparisons to other related genomes including uncultivated ones, based on the genome-aggregate Average Nucleotide and Amino Acid Identity (ANI/AAI) concepts. MiGA integrates best practices in sequence quality trimming and assembly and allows input to be raw reads or assemblies from isolate genomes, single-cell sequences, and metagenome-assembled genomes (MAGs). Further, MiGA can take as input hundreds of closely related genomes of the same or closely related species (a so-called 'Clade Project') to assess their gene content diversity and evolutionary relationships, and calculate important clade properties such as the pangenome and core gene sets. Therefore, MiGA is expected to facilitate a range of genome-based taxonomic and diversity studies, and quality assessment across environmental and clinical settings. MiGA is available at http://microbial-genomes.org/.},
}
@article {pmid29897479,
year = {2018},
author = {Feng, X and Sun, M and Han, W and Liang, YX and She, Q},
title = {A transcriptional factor B paralog functions as an activator to DNA damage-responsive expression in archaea.},
journal = {Nucleic acids research},
volume = {46},
number = {14},
pages = {7465},
doi = {10.1093/nar/gky302},
pmid = {29897479},
issn = {1362-4962},
}
@article {pmid29891388,
year = {2018},
author = {Marshall, A and Phillips, L and Longmore, A and Tang, C and Heidelberg, K and Mele, P},
title = {Primer selection influences abundance estimates of ammonia oxidizing archaea in coastal marine sediments.},
journal = {Marine environmental research},
volume = {140},
number = {},
pages = {90-95},
doi = {10.1016/j.marenvres.2018.06.001},
pmid = {29891388},
issn = {1879-0291},
mesh = {Ammonia/*metabolism ; Archaea/*physiology ; Archaeal Proteins ; Australia ; Biodiversity ; DNA, Archaeal ; DNA, Bacterial ; Geologic Sediments/chemistry/*microbiology ; Oxidation-Reduction ; Oxidoreductases ; Phylogeny ; Seawater ; Sequence Analysis, DNA ; Water Pollutants, Chemical/*metabolism ; },
abstract = {Quantification of the α-subunit of ammonia monooxygenase (amoA) through PCR is an established technique for estimating the abundance of ammonia oxidizing archaea (AOA) in environmental samples. This study quantified AOA with two established primer sets in 1 cm increments from the sediment surface (0-1 cm) to a depth of 10 cm at two locations within Port Phillip Bay (PPB), Australia. Primer choice had a significant effect on within sample estimates of AOA with copy numbers ranging from 102 to 104 copies per ng DNA. Variation in AOA abundance patterns with increasing sediment depth were site and primer specific. Sequence mismatches between the primer binding region of the isolated amoA sequences from PPB and Nitrosopumilus maritimus SCM1 were identified and may explain the high variation identified between primer estimates. Our results highlight the need for testing multiple primer pairs that target different regions of the AOA amoA sequence prior to large-scale marine sediment environmental studies.},
}
@article {pmid29888297,
year = {2018},
author = {Fu, X and Adams, Z and Maupin-Furlow, JA},
title = {In vitro Analysis of Ubiquitin-like Protein Modification in Archaea.},
journal = {Bio-protocol},
volume = {8},
number = {10},
pages = {},
pmid = {29888297},
issn = {2331-8325},
support = {R01 GM057498/GM/NIGMS NIH HHS/United States ; },
abstract = {The ubiquitin-like (Ubl) protein is widely distributed in Archaea and involved in many cellular pathways. A well-established method to reconstitute archaeal Ubl protein conjugation in vitro is important to better understand the process of archaeal Ubl protein modification. This protocol describes the in vitro reconstitution of Ubl protein modification and following analysis of this modification in Haloferax volcanii, a halophilic archaeon serving as the model organism.},
}
@article {pmid29879486,
year = {2018},
author = {McDougall, M and McEleney, K and Francisco, O and Trieu, B and Ogbomo, EK and Tomy, G and Stetefeld, J},
title = {Reductive power of the archaea right-handed coiled coil nanotube (RHCC-NT) and incorporation of mercury clusters inside protein cages.},
journal = {Journal of structural biology},
volume = {203},
number = {3},
pages = {281-287},
doi = {10.1016/j.jsb.2018.05.013},
pmid = {29879486},
issn = {1095-8657},
abstract = {Coiled coils are well described as powerful oligomerization motifs and exhibit a large diversity of functions, including gene regulation, cell division, membrane fusion and drug extrusion. The archaea S-layer originated right-handed coiled coil -RHCC-NT- is characterized by extreme stability and is free of cysteine and histidine moieties. In the current study, we have followed a multidisciplinary approach to investigate the capacity of RHCC-NT to bind a variety of ionic complex metal ions. At the outside of the RHCC-NT, one mercury ion forms an electrostatic interaction with the S-methyl moiety of the single methionine residue present in each coil. We demonstrate that RHCC-NT is reducing and incorporating metallic mercury in the large-sized interior cavities which are lined up along the tetrameric channel.},
}
@article {pmid29878182,
year = {2018},
author = {Sun, M and Feng, X and Liu, Z and Han, W and Liang, YX and She, Q},
title = {An Orc1/Cdc6 ortholog functions as a key regulator in the DNA damage response in Archaea.},
journal = {Nucleic acids research},
volume = {46},
number = {13},
pages = {6697-6711},
pmid = {29878182},
issn = {1362-4962},
mesh = {4-Nitroquinoline-1-oxide/toxicity ; Archaeal Proteins/genetics/metabolism/*physiology ; Cell Cycle ; Cell Cycle Proteins/genetics/metabolism/*physiology ; DNA Damage ; *DNA Repair ; DNA, Archaeal/chemistry ; Gene Deletion ; Gene Expression/drug effects ; Nucleotide Motifs ; Origin Recognition Complex/genetics/metabolism/*physiology ; Promoter Regions, Genetic ; Sulfolobus/drug effects/*genetics/metabolism ; },
abstract = {While bacteria and eukaryotes show distinct mechanisms of DNA damage response (DDR) regulation, investigation of ultraviolet (UV)-responsive expression in a few archaea did not yield any conclusive evidence for an archaeal DDR regulatory network. Nevertheless, expression of Orc1-2, an ortholog of the archaeal origin recognition complex 1/cell division control protein 6 (Orc1/Cdc6) superfamily proteins was strongly activated in Sulfolobus solfataricus and Sulfolobus acidocaldarius upon UV irradiation. Here, a series of experiments were conducted to investigate the possible functions of Orc1-2 in DNA damage repair in Sulfolobus islandicus. Study of DDR in Δorc1-2 revealed that Orc1-2 deficiency abolishes DNA damage-induced differential expression of a large number of genes and the mutant showed hypersensitivity to DNA damage treatment. Reporter gene and DNase I footprinting assays demonstrated that Orc1-2 interacts with a conserved hexanucleotide motif present in several DDR gene promoters and regulates their expression. Manipulation of orc1-2 expression by promoter substitution in this archaeon revealed that a high level of orc1-2 expression is essential but not sufficient to trigger DDR. Together, these results have placed Orc1-2 in the heart of the archaeal DDR regulation, and the resulting Orc1-2-centered regulatory circuit represents the first DDR network identified in Archaea, the third domain of life.},
}
@article {pmid29806626,
year = {2018},
author = {Mihara, T and Koyano, H and Hingamp, P and Grimsley, N and Goto, S and Ogata, H},
title = {Taxon Richness of &quot;Megaviridae&quot; Exceeds those of Bacteria and Archaea in the Ocean.},
journal = {Microbes and environments},
volume = {33},
number = {2},
pages = {162-171},
pmid = {29806626},
issn = {1347-4405},
mesh = {Archaea/*classification/genetics ; Bacteria/*classification/genetics ; *Biodiversity ; Databases, Genetic ; Evolution, Molecular ; Giant Viruses/*classification/genetics ; Metagenomics ; *Oceans and Seas ; *Phylogeny ; RNA Polymerase II/genetics ; },
abstract = {Since the discovery of the giant mimivirus, evolutionarily related viruses have been isolated or identified from various environments. Phylogenetic analyses of this group of viruses, tentatively referred to as the family &quot;Megaviridae&quot;, suggest that it has an ancient origin that may predate the emergence of major eukaryotic lineages. Environmental genomics has since revealed that Megaviridae represents one of the most abundant and diverse groups of viruses in the ocean. In the present study, we compared the taxon richness and phylogenetic diversity of Megaviridae, Bacteria, and Archaea using DNA-dependent RNA polymerase as a common marker gene. By leveraging existing microbial metagenomic data, we found higher richness and phylogenetic diversity in this single viral family than in the two prokaryotic domains. We also obtained results showing that the evolutionary rate alone cannot account for the observed high diversity of Megaviridae lineages. These results suggest that the Megaviridae family has a deep co-evolutionary history with diverse marine protists since the early &quot;Big-Bang&quot; radiation of the eukaryotic tree of life.},
}
@article {pmid29797436,
year = {2018},
author = {Ramiro, FS and de Lira, E and Soares, G and Retamal-Valdes, B and Feres, M and Figueiredo, LC and Faveri, M},
title = {Effects of different periodontal treatments in changing the prevalence and levels of Archaea present in the subgingival biofilm of subjects with periodontitis: A secondary analysis from a randomized controlled clinical trial.},
journal = {International journal of dental hygiene},
volume = {16},
number = {4},
pages = {569-575},
doi = {10.1111/idh.12347},
pmid = {29797436},
issn = {1601-5037},
support = {2013/10139-6//São Paulo Research Foundation (FAPESP, Brazil)/ ; 2012/23503-5//São Paulo Research Foundation (FAPESP, Brazil)/ ; },
mesh = {Adult ; Amoxicillin/*administration &amp; dosage ; Archaea/*isolation &amp; purification ; *Biofilms ; Chronic Periodontitis/*microbiology/*therapy ; Combined Modality Therapy ; Dental Plaque/*microbiology ; *Dental Scaling ; Drug Therapy, Combination ; Female ; Gingiva/*microbiology ; Humans ; Male ; Metronidazole/*administration &amp; dosage ; Middle Aged ; *Root Planing ; Time Factors ; Treatment Outcome ; },
abstract = {OBJECTIVE: The aim of this randomized double-blind and placebo-controlled study was to assess if periodontal treatment with or without systemic antibiotic would change the mean level of Archaea.<br><br>METHODS: Fifty-nine (59) subjects were randomly assigned to receive scaling and root planing (SRP) alone or combined with metronidazole (MTZ; 400 mg/TID) or either with MTZ and amoxicillin (AMX; 500 mg/TID) for 14 days. Clinical and microbiological examinations were performed at baseline and at 6 months post-SRP. Six subgingival plaque samples per subject were analysed for the presence and levels of Archaea using quantitative polymerase chain reaction.<br><br>RESULTS: Scaling and root planing alone or combined with MTZ or MTZ + AMX significantly reduced the prevalence of subjects colonized by Archaea at 6 months post-therapy, without significant differences among groups (P > .05). Both therapies led to a statistically significant decrease in the mean percentage of sites colonized by Archaea (P < .05). The MTZ and MTZ + AMX group had a significantly lower mean number of sites colonized by Archaea and lower levels of these micro-organisms at sites with probing depth ≥5 mm at 6 months compared with SRP group (P < .05).<br><br>CONCLUSION: Periodontal treatments including adjunctive MTZ or MTZ + AMX are more effective than mechanical treatment alone in reducing the levels and prevalence of sites colonized by Archaea in subjects with chronic periodontitis.},
}
@article {pmid29795539,
year = {2018},
author = {Teske, A},
title = {Aerobic Archaea in iron-rich springs.},
journal = {Nature microbiology},
volume = {3},
number = {6},
pages = {646-647},
doi = {10.1038/s41564-018-0168-9},
pmid = {29795539},
issn = {2058-5276},
mesh = {*Archaea ; Ferric Compounds ; *Hot Springs ; Iron ; },
}
@article {pmid29789313,
year = {2018},
author = {Pedraza-Pérez, Y and Cuevas-Vede, RA and Canto-Gómez, ÁB and López-Pliego, L and Gutiérrez-Ríos, RM and Hernández-Lucas, I and Rubín-Linares, G and Martínez-Laguna, Y and López-Olguín, JF and Fuentes-Ramírez, LE},
title = {BLAST-XYPlot Viewer: A Tool for Performing BLAST in Whole-Genome Sequenced Bacteria/Archaea and Visualize Whole Results Simultaneously.},
journal = {G3 (Bethesda, Md.)},
volume = {8},
number = {7},
pages = {2167-2172},
pmid = {29789313},
issn = {2160-1836},
mesh = {Archaea/genetics ; Bacteria/genetics ; Computational Biology/*methods ; Databases, Genetic ; Genome, Archaeal ; Genome, Bacterial ; Genomics/methods ; *Software ; User-Computer Interface ; Whole Genome Sequencing ; },
abstract = {One of the most commonly used tools to compare protein or DNA sequences against databases is BLAST. We introduce a web tool that allows the performance of BLAST-searches of protein/DNA sequences in whole-genome sequenced bacteria/archaea, and displays a large amount of BLAST-results simultaneously. The circular bacterial replicons are projected as horizontal lines with fixed length of 360, representing the degrees of a circle. A coordinate system is created with length of the replicon along the x-axis and the number of replicon used on the y-axis. When a query sequence matches with a gene/protein of a particular replicon, the BLAST-results are depicted as an &quot;x,y&quot; position in a specially adapted plot. This tool allows the visualization of the results from the whole data to a particular gene/protein in real time with low computational resources.},
}
@article {pmid29788499,
year = {2018},
author = {Nawrocki, EP and Jones, TA and Eddy, SR},
title = {Group I introns are widespread in archaea.},
journal = {Nucleic acids research},
volume = {46},
number = {15},
pages = {7970-7976},
pmid = {29788499},
issn = {1362-4962},
support = {R01 HG009116/HG/NHGRI NIH HHS/United States ; },
mesh = {Archaea/classification/enzymology/*genetics ; Base Sequence ; Introns/*genetics ; Nucleic Acid Conformation ; Phylogeny ; RNA, Archaeal/chemistry/classification/*genetics ; RNA, Catalytic/chemistry/classification/*genetics ; Species Specificity ; },
abstract = {Group I catalytic introns have been found in bacterial, viral, organellar, and some eukaryotic genomes, but not in archaea. All known archaeal introns are bulge-helix-bulge (BHB) introns, with the exception of a few group II introns. It has been proposed that BHB introns arose from extinct group I intron ancestors, much like eukaryotic spliceosomal introns are thought to have descended from group II introns. However, group I introns have little sequence conservation, making them difficult to detect with standard sequence similarity searches. Taking advantage of recent improvements in a computational homology search method that accounts for both conserved sequence and RNA secondary structure, we have identified 39 group I introns in a wide range of archaeal phyla, including examples of group I introns and BHB introns in the same host gene.},
}
@article {pmid29771354,
year = {2018},
author = {Lui, LM and Uzilov, AV and Bernick, DL and Corredor, A and Lowe, TM and Dennis, PP},
title = {Methylation guide RNA evolution in archaea: structure, function and genomic organization of 110 C/D box sRNA families across six Pyrobaculum species.},
journal = {Nucleic acids research},
volume = {46},
number = {11},
pages = {5678-5691},
pmid = {29771354},
issn = {1362-4962},
support = {T32 GM070386/GM/NIGMS NIH HHS/United States ; },
mesh = {Archaeal Proteins/genetics ; Base Pair Mismatch ; *Evolution, Molecular ; Genes, Duplicate ; Genomics ; Methylation ; Multigene Family ; Pyrobaculum/*genetics ; RNA, Archaeal/chemistry/classification/*genetics/metabolism ; RNA, Ribosomal/metabolism ; RNA, Small Nucleolar/chemistry/classification/*genetics/metabolism ; RNA, Transfer/metabolism ; RNA, Untranslated/genetics ; Sequence Alignment ; },
abstract = {Archaeal homologs of eukaryotic C/D box small nucleolar RNAs (C/D box sRNAs) guide precise 2'-O-methyl modification of ribosomal and transfer RNAs. Although C/D box sRNA genes constitute one of the largest RNA gene families in archaeal thermophiles, most genomes have incomplete sRNA gene annotation because reliable, fully automated detection methods are not available. We expanded and curated a comprehensive gene set across six species of the crenarchaeal genus Pyrobaculum, particularly rich in C/D box sRNA genes. Using high-throughput small RNA sequencing, specialized computational searches and comparative genomics, we analyzed 526 Pyrobaculum C/D box sRNAs, organizing them into 110 families based on synteny and conservation of guide sequences which determine methylation targets. We examined gene duplications and rearrangements, including one family that has expanded in a pattern similar to retrotransposed repetitive elements in eukaryotes. New training data and inclusion of kink-turn secondary structural features enabled creation of an improved search model. Our analyses provide the most comprehensive, dynamic view of C/D box sRNA evolutionary history within a genus, in terms of modification function, feature plasticity, and gene mobility.},
}
@article {pmid29769540,
year = {2018},
author = {Xu, S and Cai, C and Guo, J and Lu, W and Yuan, Z and Hu, S},
title = {Different clusters of Candidatus 'Methanoperedens nitroreducens'-like archaea as revealed by high-throughput sequencing with new primers.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {7695},
pmid = {29769540},
issn = {2045-2322},
abstract = {The newly discovered Candidatus 'Methanoperedens nitroreducens' (M. nitroreducens), mediating nitrate-dependent anaerobic oxidation of methane, is an important microorganism in linking carbon and nitrogen cycles. In order to explore the diversity of M. nitroreducens-like archaea in various environmental niches with advanced high-throughput sequencing, new primers based on alpha subunit of methyl-coenzyme M reductase gene were designed. The PCR results demonstrated that the new primers could effectively detect M. nitroreducens-like archaea from an enrichment culture dominated by M. nitroreducens as well as samples collected from a natural freshwater lake and a full-scale wastewater treatment plant (WWTP). By high-throughput sequencing, more than 30,000 M. nitroreducens-like sequences were obtained. Phylogenetic analysis of these sequences along with published sequences showed that M. nitroreducens-like archaea could be divided into three sub-branches (named as Group A, Group B and Group C in this study). Clear geographical difference was observed, with Group A and Group B dominating samples in Queensland (Australia) and in European ecosystems, respectively. Further quantitative PCR revealed that the M. nitroreducens-like archaea were more abundant in WWTP than the freshwater lake. The study provided a large number of sequences for M. nitroreducens-like archaeal communities, thus expanded our understanding on the ecological diversity of M. nitroreducens-like archaea.},
}
@article {pmid29757234,
year = {2018},
author = {Sinha, N and Kral, TA},
title = {Effect of UVC Radiation on Hydrated and Desiccated Cultures of Slightly Halophilic and Non-Halophilic Methanogenic Archaea: Implications for Life on Mars.},
journal = {Microorganisms},
volume = {6},
number = {2},
pages = {},
pmid = {29757234},
issn = {2076-2607},
abstract = {Methanogens have been considered models for life on Mars for many years. In order to survive any exposure at the surface of Mars, methanogens would have to endure Martian UVC radiation. In this research, we irradiated hydrated and desiccated cultures of slightly halophilic Methanococcus maripaludis and non-halophilic Methanobacterium formicicum for various time intervals with UVC (254 nm) radiation. The survivability of the methanogens was determined by measuring methane concentrations in the headspace gas samples of culture tubes after re-inoculation of the methanogens into their growth-supporting media following exposure to UVC radiation. Hydrated M. maripaludis survived 24 h of UVC exposure, while in a desiccated condition they endured for 16 h. M. formicicum also survived UVC radiation for 24 h in a liquid state; however, in a desiccated condition, the survivability of M. formicicum was only 12 h. Some of the components of the growth media could have served as shielding agents that protected cells from damage caused by exposure to ultraviolet radiation. Overall, these results suggest that limited exposure (12⁻24 h) to UVC radiation on the surface of Mars would not necessarily be a limiting factor for the survivability of M. maripaludis and M. formicicum.},
}
@article {pmid29753224,
year = {2018},
author = {Liu, X and Pan, J and Liu, Y and Li, M and Gu, JD},
title = {Diversity and distribution of Archaea in global estuarine ecosystems.},
journal = {The Science of the total environment},
volume = {637-638},
number = {},
pages = {349-358},
doi = {10.1016/j.scitotenv.2018.05.016},
pmid = {29753224},
issn = {1879-1026},
mesh = {Archaea/classification/*genetics/growth &amp; development ; Biodiversity ; DNA, Archaeal ; Ecosystem ; *Estuaries ; Phylogeny ; RNA, Ribosomal, 16S ; Sequence Analysis, DNA ; *Water Microbiology ; },
abstract = {Estuarine ecosystem is a unique geographical transitional zone between freshwater and seawater, harboring a wide range of microbial communities including Archaea. Although a large number of Archaea have been detected in such ecosystem, the global patterns in archaeal diversity and distribution are extremely scarce. To bridge this gap, we carried out a comprehensive survey of archaeal communities using ca. 4000 publicly available archaeal 16S rRNA gene sequences (>300 bp) collected from 24 estuaries in different latitude regions. These sequences were divided into 1450 operational taxonomic units (OTUs) at 97% identity, suggesting a high biodiversity that increased gradually from the high- to low-latitude estuaries. Phylogenetic analysis showed that estuarine ecosystem was a large biodiversity pool of Archaea that was mainly composed of 12 phyla. Among them, the predominant groups were Bathyarchaeota, Euryarchaeota and Thaumarchaeota. Interestingly, archaeal distribution demonstrated a geographical differentiation in that Thaumarchaeota was dominated in the low-latitude estuaries, Bathyarchaeota in the mid-latitude estuaries, and Euryarchaeota in the high-latitude estuaries, respectively. Furthermore, the majority of the most abundant 20 OTUs demonstrated an overrepresented or underrepresented distribution pattern in some specific estuaries or latitude regions while a few were evenly distributed throughout the estuaries. This pattern indicates a potential selectivity of geographical distribution. In addition, the analysis of environmental parameters suggested that latitude would be one of the major factors driving the distribution of archaeal communities in estuarine ecosystem. This study profiles a clear framework on the diversity and distribution of Archaea in the global estuarine ecosystem and explores the general environmental factors that influence these patterns. Our findings constitute an important part of the exploration of the global ecology of Archaea.},
}
@article {pmid29743201,
year = {2018},
author = {Taffner, J and Erlacher, A and Bragina, A and Berg, C and Moissl-Eichinger, C and Berg, G},
title = {What Is the Role of Archaea in Plants? New Insights from the Vegetation of Alpine Bogs.},
journal = {mSphere},
volume = {3},
number = {3},
pages = {},
pmid = {29743201},
issn = {2379-5042},
mesh = {Archaea/*growth &amp; development/*metabolism ; Ecosystem ; Plants/*microbiology ; *Symbiosis ; Wetlands ; },
abstract = {The Archaea represent a significant component of the plant microbiome, whereas their function is still unclear. Different plant species representing the natural vegetation of alpine bogs harbor a substantial archaeal community originating from five phyla, 60 genera, and 334 operational taxonomic units (OTUs). We identified a core archaeome for all bog plants and ecosystem-specific, so far unclassified Archaea In the metagenomic data set, Archaea were found to have the potential to interact with plants by (i) possible plant growth promotion through auxin biosynthesis, (ii) nutrient supply, and (iii) protection against abiotic (especially oxidative and osmotic) stress. The unexpectedly high degree of plant specificity supports plant-archaeon interactions. Moreover, functional signatures of Archaea reveal genetic capacity for the interplay with fungi and an important role in the carbon and nitrogen cycle: e.g., CO2 and N2 fixation. These facts reveal an important, yet unobserved role of the Archaea for plants as well as for the bog ecosystem.IMPORTANCEArchaea are still an underdetected and little-studied part of the plant microbiome. We provide first and novel insights into Archaea as a functional component of the plant microbiome obtained by metagenomic analyses. Archaea were found to have the potential to interact with plants by (i) plant growth promotion through auxin biosynthesis, (ii) nutrient supply, and (iii) protection against abiotic stress.},
}
@article {pmid29741625,
year = {2018},
author = {White, MF and Allers, T},
title = {DNA repair in the archaea-an emerging picture.},
journal = {FEMS microbiology reviews},
volume = {42},
number = {4},
pages = {514-526},
doi = {10.1093/femsre/fuy020},
pmid = {29741625},
issn = {1574-6976},
support = {//Biotechnology and Biological Sciences Research Council/United Kingdom ; },
mesh = {Archaea/*genetics ; *Biological Evolution ; DNA Repair/*physiology ; DNA, Archaeal/*genetics ; },
abstract = {There has long been a fascination in the DNA repair pathways of archaea, for two main reasons. Firstly, many archaea inhabit extreme environments where the rate of physical damage to DNA is accelerated. These archaea might reasonably be expected to have particularly robust or novel DNA repair pathways to cope with this. Secondly, the archaea have long been understood to be a lineage distinct from the bacteria, and to share a close relationship with the eukarya, particularly in their information processing systems. Recent discoveries suggest the eukarya arose from within the archaeal domain, and in particular from lineages related to the TACK superphylum and Lokiarchaea. Thus, archaeal DNA repair proteins and pathways can represent a useful model system. This review focuses on recent advances in our understanding of archaeal DNA repair processes including base excision repair, nucleotide excision repair, mismatch repair and double-strand break repair. These advances are discussed in the context of the emerging picture of the evolution and relationship of the three domains of life.},
}
@article {pmid29733685,
year = {2018},
author = {Rinta-Kanto, JM and Pehkonen, K and Sinkko, H and Tamminen, MV and Timonen, S},
title = {Archaea are prominent members of the prokaryotic communities colonizing common forest mushrooms.},
journal = {Canadian journal of microbiology},
volume = {64},
number = {10},
pages = {716-726},
doi = {10.1139/cjm-2018-0035},
pmid = {29733685},
issn = {1480-3275},
mesh = {*Agaricales ; Archaea/genetics/*isolation &amp; purification ; Bacteria/genetics/isolation &amp; purification ; *Forests ; RNA, Ribosomal, 16S/genetics ; },
abstract = {In this study, the abundance and composition of prokaryotic communities associated with the inner tissue of fruiting bodies of Suillus bovinus, Boletus pinophilus, Cantharellus cibarius, Agaricus arvensis, Lycoperdon perlatum, and Piptoporus betulinus were analyzed using culture-independent methods. Our findings indicate that archaea and bacteria colonize the internal tissues of all investigated specimens and that archaea are prominent members of the prokaryotic community. The ratio of archaeal 16S rRNA gene copy numbers to those of bacteria was >1 in the fruiting bodies of four out of six fungal species included in the study. The largest proportion of archaeal 16S rRNA gene sequences belonged to thaumarchaeotal classes Terrestrial group, Miscellaneous Crenarchaeotic Group (MCG), and Thermoplasmata. Bacterial communities showed characteristic compositions in each fungal species. Bacterial classes Gammaproteobacteria, Actinobacteria, Bacilli, and Clostridia were prominent among communities in fruiting body tissues. Bacterial populations in each fungal species had different characteristics. The results of this study imply that fruiting body tissues are an important habitat for abundant and diverse populations of archaea and bacteria.},
}
@article {pmid29720404,
year = {2018},
author = {Prakash, D and Walters, KA and Martinie, RJ and McCarver, AC and Kumar, AK and Lessner, DJ and Krebs, C and Golbeck, JH and Ferry, JG},
title = {Toward a mechanistic and physiological understanding of a ferredoxin:disulfide reductase from the domains Archaea and Bacteria.},
journal = {The Journal of biological chemistry},
volume = {293},
number = {24},
pages = {9198-9209},
pmid = {29720404},
issn = {1083-351X},
mesh = {Archaea/chemistry/*enzymology/metabolism ; Bacteria/chemistry/*enzymology/metabolism ; Catalytic Domain ; Disulfides/chemistry/*metabolism ; Electron Transport ; Ferredoxins/chemistry/*metabolism ; Iron-Sulfur Proteins/chemistry/*metabolism ; Methanosarcina/chemistry/*enzymology/metabolism ; Models, Molecular ; NADH, NADPH Oxidoreductases/chemistry/*metabolism ; Oxidation-Reduction ; Oxidoreductases/chemistry/*metabolism ; Spinacia oleracea/chemistry/enzymology/metabolism ; },
abstract = {Disulfide reductases reduce other proteins and are critically important for cellular redox signaling and homeostasis. Methanosarcina acetivorans is a methane-producing microbe from the domain Archaea that produces a ferredoxin:disulfide reductase (FDR) for which the crystal structure has been reported, yet its biochemical mechanism and physiological substrates are unknown. FDR and the extensively characterized plant-type ferredoxin:thioredoxin reductase (FTR) belong to a distinct class of disulfide reductases that contain a unique active-site [4Fe-4S] cluster. The results reported here support a mechanism for FDR similar to that reported for FTR with notable exceptions. Unlike FTR, FDR contains a rubredoxin [1Fe-0S] center postulated to mediate electron transfer from ferredoxin to the active-site [4Fe-4S] cluster. UV-visible, EPR, and Mössbauer spectroscopic data indicated that two-electron reduction of the active-site disulfide in FDR involves a one-electron-reduced [4Fe-4S]1+ intermediate previously hypothesized for FTR. Our results support a role for an active-site tyrosine in FDR that occupies the equivalent position of an essential histidine in the active site of FTR. Of note, one of seven Trxs encoded in the genome (Trx5) and methanoredoxin, a glutaredoxin-like enzyme from M. acetivorans, were reduced by FDR, advancing the physiological understanding of FDR's role in the redox metabolism of methanoarchaea. Finally, bioinformatics analyses show that FDR homologs are widespread in diverse microbes from the domain Bacteria.},
}
@article {pmid29699482,
year = {2018},
author = {Mitić, NS and Malkov, SN and Kovačević, JJ and Pavlović-Lažetić, GM and Beljanski, MV},
title = {Structural disorder of plasmid-encoded proteins in Bacteria and Archaea.},
journal = {BMC bioinformatics},
volume = {19},
number = {1},
pages = {158},
pmid = {29699482},
issn = {1471-2105},
support = {174021//Ministry of Education, Science and Technological Development, Republic of Serbia/International ; },
mesh = {Archaea/*genetics ; Archaeal Proteins/*chemistry ; Bacteria/*genetics ; Bacterial Proteins/*chemistry ; Chromosomes, Archaeal/metabolism ; Chromosomes, Bacterial/metabolism ; Intrinsically Disordered Proteins/*chemistry ; Plasmids/*metabolism ; Proteome/metabolism ; Toxins, Biological/chemistry ; },
abstract = {BACKGROUND: In the last decade and a half it has been firmly established that a large number of proteins do not adopt a well-defined (ordered) structure under physiological conditions. Such intrinsically disordered proteins (IDPs) and intrinsically disordered (protein) regions (IDRs) are involved in essential cell processes through two basic mechanisms: the entropic chain mechanism which is responsible for rapid fluctuations among many alternative conformations, and molecular recognition via short recognition elements that bind to other molecules. IDPs possess a high adaptive potential and there is special interest in investigating their involvement in organism evolution.<br><br>RESULTS: We analyzed 2554 Bacterial and 139 Archaeal proteomes, with a total of 8,455,194 proteins for disorder content and its implications for adaptation of organisms, using three disorder predictors and three measures. Along with other findings, we revealed that for all three predictors and all three measures (1) Bacteria exhibit significantly more disorder than Archaea; (2) plasmid-encoded proteins contain considerably more IDRs than proteins encoded on chromosomes (or whole genomes) in both prokaryote superkingdoms; (3) plasmid proteins are significantly more disordered than chromosomal proteins only in the group of proteins with no COG category assigned; (4) antitoxin proteins in comparison to other proteins, are the most disordered (almost double) in both Bacterial and Archaeal proteomes; (5) plasmidal proteins are more disordered than chromosomal proteins in Bacterial antitoxins and toxin-unclassified proteins, but have almost the same disorder content in toxin proteins.<br><br>CONCLUSION: Our results suggest that while disorder content depends on genome and proteome characteristics, it is more influenced by functional engagements than by gene location (on chromosome or plasmid).},
}
@article {pmid29687586,
year = {2018},
author = {Meinhardt, KA and Stopnisek, N and Pannu, MW and Strand, SE and Fransen, SC and Casciotti, KL and Stahl, DA},
title = {Ammonia-oxidizing bacteria are the primary N2 O producers in an ammonia-oxidizing archaea dominated alkaline agricultural soil.},
journal = {Environmental microbiology},
volume = {20},
number = {6},
pages = {2195-2206},
doi = {10.1111/1462-2920.14246},
pmid = {29687586},
issn = {1462-2920},
support = {DE-SC0006869//Genomic Science and Technology for Energy and the Environment/International ; },
abstract = {Most agricultural N2 O emissions are a consequence of microbial transformations of nitrogen (N) fertilizer, and mitigating increases in N2 O emission will depend on identifying microbial sources and variables influencing their activities. Here, using controlled microcosm and field studies, we found that synthetic N addition in any tested amount stimulated the production of N2 O from ammonia-oxidizing bacteria (AOB), but not archaea (AOA), from a bioenergy crop soil. The activities of these two populations were differentiated by N treatments, with abundance and activity of AOB increasing as nitrate and N2 O production increased. Moreover, as N2 O production increased, the isotopic composition of N2 O was consistent with an AOB source. Relative N2 O contributions by both populations were quantified using selective inhibitors and varying N availability. Complementary field analyses confirmed a positive correlation between N2 O flux and AOB abundance with N application. Collectively, our data indicate that AOB are the major N2 O producers, even with low N addition, and that better-metered N application, complemented by selective inhibitors, could reduce projected N2 O emissions from agricultural soils.},
}
@article {pmid29684598,
year = {2018},
author = {Aouad, M and Taib, N and Oudart, A and Lecocq, M and Gouy, M and Brochier-Armanet, C},
title = {Extreme halophilic archaea derive from two distinct methanogen Class II lineages.},
journal = {Molecular phylogenetics and evolution},
volume = {127},
number = {},
pages = {46-54},
doi = {10.1016/j.ympev.2018.04.011},
pmid = {29684598},
issn = {1095-9513},
mesh = {Bayes Theorem ; Conserved Sequence ; Euryarchaeota/*classification ; Genes, Archaeal ; Genomics ; *Phylogeny ; *Salinity ; },
abstract = {Phylogenetic analyses of conserved core genes have disentangled most of the ancient relationships in Archaea. However, some groups remain debated, like the DPANN, a deep-branching super-phylum composed of nanosized archaea with reduced genomes. Among these, the Nanohaloarchaea require high-salt concentrations for growth. Their discovery in 2012 was significant because they represent, together with Halobacteria (a Class belonging to Euryarchaeota), the only two described lineages of extreme halophilic archaea. The phylogenetic position of Nanohaloarchaea is highly debated, being alternatively proposed as the sister-lineage of Halobacteria or a member of the DPANN super-phylum. Pinpointing the phylogenetic position of extreme halophilic archaea is important to improve our knowledge of the deep evolutionary history of Archaea and the molecular adaptive processes and evolutionary paths that allowed their emergence. Using comparative genomic approaches, we identified 258 markers carrying a reliable phylogenetic signal. By combining strategies limiting the impact of biases on phylogenetic inference, we showed that Nanohaloarchaea and Halobacteria represent two independent lines that derived from two distinct but related methanogen Class II lineages. This implies that adaptation to high salinity emerged twice independently in Archaea and indicates that emergence of Nanohaloarchaea within DPANN in previous studies is likely the consequence of a tree reconstruction artifact, challenging the existence of this super-phylum.},
}
@article {pmid29684129,
year = {2018},
author = {Clouet-d'Orval, B and Batista, M and Bouvier, M and Quentin, Y and Fichant, G and Marchfelder, A and Maier, LK},
title = {Insights into RNA-processing pathways and associated RNA-degrading enzymes in Archaea.},
journal = {FEMS microbiology reviews},
volume = {42},
number = {5},
pages = {579-613},
doi = {10.1093/femsre/fuy016},
pmid = {29684129},
issn = {1574-6976},
mesh = {Archaea/*enzymology/metabolism ; Endoribonucleases/*metabolism ; Exoribonucleases/*metabolism ; RNA Processing, Post-Transcriptional/*physiology ; },
abstract = {RNA-processing pathways are at the centre of regulation of gene expression. All RNA transcripts undergo multiple maturation steps in addition to covalent chemical modifications to become functional in the cell. This includes destroying unnecessary or defective cellular RNAs. In Archaea, information on mechanisms by which RNA species reach their mature forms and associated RNA-modifying enzymes are still fragmentary. To date, most archaeal actors and pathways have been proposed in light of information gathered from Bacteria and Eukarya. In this context, this review provides a state of the art overview of archaeal endoribonucleases and exoribonucleases that cleave and trim RNA species and also of the key small archaeal proteins that bind RNAs. Furthermore, synthetic up-to-date views of processing and biogenesis pathways of archaeal transfer and ribosomal RNAs as well as of maturation of stable small non-coding RNAs such as CRISPR RNAs, small C/D and H/ACA box guide RNAs, and other emerging classes of small RNAs are described. Finally, prospective post-transcriptional mechanisms to control archaeal messenger RNA quality and quantity are discussed.},
}
@article {pmid29672703,
year = {2018},
author = {Keshri, V and Panda, A and Levasseur, A and Rolain, JM and Pontarotti, P and Raoult, D},
title = {Phylogenomic Analysis of β-Lactamase in Archaea and Bacteria Enables the Identification of Putative New Members.},
journal = {Genome biology and evolution},
volume = {10},
number = {4},
pages = {1106-1114},
pmid = {29672703},
issn = {1759-6653},
mesh = {Anti-Bacterial Agents/adverse effects/therapeutic use ; Archaea/enzymology ; Bacteria/enzymology ; Carbapenems/*biosynthesis/chemistry ; Humans ; Metagenomics ; *Phylogeny ; beta-Lactamases/*genetics ; beta-Lactams/*metabolism ; },
abstract = {β-lactamases are enzymes which are commonly produced by bacteria and which degrade the β-lactam ring of β-lactam antibiotics, namely penicillins, cephalosporins, carbapenems, and monobactams, and inactivate these antibiotics. We performed a rational and comprehensive investigation of β-lactamases in different biological databases. In this study, we constructed hidden Markov model profiles as well as the ancestral sequence of four classes of β-lactamases (A, B, C, and D), which were used to identify potential β-lactamases from environmental metagenomic (1206), human microbiome metagenomic (6417), human microbiome reference genome (1310), and NCBI's nonredundant databases (44101). Our analysis revealed the existence of putative β-lactamases in the metagenomic databases, which appeared to be similar to the four different molecular classes (A-D). This is the first report on the large-scale phylogenetic diversity of new members of β-lactamases, and our results revealed that metagenomic database dark-matter contains β-lactamase-like antibiotic resistance genes.},
}
@article {pmid29668953,
year = {2018},
author = {Ausiannikava, D and Mitchell, L and Marriott, H and Smith, V and Hawkins, M and Makarova, KS and Koonin, EV and Nieduszynski, CA and Allers, T},
title = {Evolution of Genome Architecture in Archaea: Spontaneous Generation of a New Chromosome in Haloferax volcanii.},
journal = {Molecular biology and evolution},
volume = {35},
number = {8},
pages = {1855-1868},
pmid = {29668953},
issn = {1537-1719},
support = {BB/M001393/1//Biotechnology and Biological Sciences Research Council/United Kingdom ; },
mesh = {*Biological Evolution ; *Chromosomes, Archaeal ; *Genome, Archaeal ; Haloferax volcanii/*genetics ; Replicon ; },
abstract = {The common ancestry of archaea and eukaryotes is evident in their genome architecture. All eukaryotic and several archaeal genomes consist of multiple chromosomes, each replicated from multiple origins. Three scenarios have been proposed for the evolution of this genome architecture: 1) mutational diversification of a multi-copy chromosome; 2) capture of a new chromosome by horizontal transfer; 3) acquisition of new origins and splitting into two replication-competent chromosomes. We report an example of the third scenario: the multi-origin chromosome of the archaeon Haloferax volcanii has split into two elements via homologous recombination. The newly generated elements are bona fide chromosomes, because each bears &quot;chromosomal&quot; replication origins, rRNA loci, and essential genes. The new chromosomes were stable during routine growth but additional genetic manipulation, which involves selective bottlenecks, provoked further rearrangements. To the best of our knowledge, rearrangement of a naturally evolved prokaryotic genome to generate two new chromosomes has not been described previously.},
}
@article {pmid29668558,
year = {2018},
author = {Brugère, JF and Ben Hania, W and Arnal, ME and Ribière, C and Ballet, N and Vandeckerkove, P and Ollivier, B and O'Toole, PW},
title = {Archaea: Microbial Candidates in Next-generation Probiotics Development.},
journal = {Journal of clinical gastroenterology},
volume = {52 Suppl 1, Proceedings from the 9th Probiotics, Prebiotics and New Foods, Nutraceuticals and Botanicals for Nutrition &amp; Human and Microbiota Health Meeting, held in Rome, Italy from September 10 to 12, 2017},
number = {},
pages = {S71-S73},
doi = {10.1097/MCG.0000000000001043},
pmid = {29668558},
issn = {1539-2031},
abstract = {Pharmabiotics and probiotics in current use or under development belong to 2 of 3 domains of life, Eukarya (eg, yeasts) and Bacteria (eg, lactobacilli). Archaea constitute a third domain of life, and are currently not used as probiotics, despite several interesting features. This includes the absence of known pathogens in humans, animals, or plants and the existence of some archaea closely associated to humans in various microbiomes. We promote the concept that some specific archaea that naturally thrive in the human gut are potential next-generation probiotics that can be rationally selected on the basis of their metabolic phenotype not being encountered in other human gut microbes, neither Bacteria nor Eukarya. The example of the possible bioremediation of the proatherogenic compound trimethylamine into methane by archaeal microbes is described.},
}
@article {pmid29666365,
year = {2018},
author = {Alves, RJE and Minh, BQ and Urich, T and von Haeseler, A and Schleper, C},
title = {Unifying the global phylogeny and environmental distribution of ammonia-oxidising archaea based on amoA genes.},
journal = {Nature communications},
volume = {9},
number = {1},
pages = {1517},
pmid = {29666365},
issn = {2041-1723},
mesh = {Ammonia/*metabolism ; Archaea/*genetics/metabolism ; *Biodiversity ; Evolution, Molecular ; Gene Frequency ; Nitrogen Cycle/genetics ; Oceans and Seas ; Oxidation-Reduction ; Oxidoreductases/*genetics ; Oxygenases/genetics ; *Phylogeny ; Soil Microbiology ; },
abstract = {Ammonia-oxidising archaea (AOA) are ubiquitous and abundant in nature and play a major role in nitrogen cycling. AOA have been studied intensively based on the amoA gene (encoding ammonia monooxygenase subunit A), making it the most sequenced functional marker gene. Here, based on extensive phylogenetic and meta-data analyses of 33,378 curated archaeal amoA sequences, we define a highly resolved taxonomy and uncover global environmental patterns that challenge many earlier generalisations. Particularly, we show: (i) the global frequency of AOA is extremely uneven, with few clades dominating AOA diversity in most ecosystems; (ii) characterised AOA do not represent most predominant clades in nature, including soils and oceans; (iii) the functional role of the most prevalent environmental AOA clade remains unclear; and (iv) AOA harbour molecular signatures that possibly reflect phenotypic traits. Our work synthesises information from a decade of research and provides the first integrative framework to study AOA in a global context.},
}
@article {pmid29656122,
year = {2018},
author = {Rother, M and Quitzke, V},
title = {Selenoprotein synthesis and regulation in Archaea.},
journal = {Biochimica et biophysica acta. General subjects},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.bbagen.2018.04.008},
pmid = {29656122},
issn = {0304-4165},
abstract = {BACKGROUND: The major biological form of selenium is that of the co-translationally inserted amino acid selenocysteine (Sec). In Archaea, the majority of proteins containing Sec, selenoproteins, are involved in methanogenesis. However, the function of this residue is often not known because selenium-independent homologs of the selenoproteins can be employed, sometimes even in one organism.<br><br>SCOPE OF REVIEW: This review summarizes current knowledge about the selenoproteins of Archaea, the metabolic pathways where they are involved, and discusses the (potential) function of individual Sec residues. Also, what is known about the &quot;archaeal&quot; way of selenoprotein synthesis, and the regulatory mechanism leading to the replacement of the selenoproteins with selenium-independent homologs, will be presented. Where appropriate, similarities with (and differences to) the respective steps employed in the other two domains, Bacteria and Eukarya, will be emphasized.<br><br>MAJOR CONCLUSIONS: Genetic and biochemical studies guided by analysis of genome sequences of Sec-encoding archaea has revealed that the pathway of Sec synthesis in Archaea and Eukarya are principally identical and that Sec insertion in Eukarya probably evolved from an archaeal mechanism employed prior to the separation of the archaeal and eukaryal lines of decent.<br><br>GENERAL SIGNIFICANCE: In light of the emerging close phylogenetic relationship of Eukarya and Archaea, archaeal models may be highly valuable tools for unraveling &quot;eukaryotic&quot; principles in molecular and cell biology.},
}
@article {pmid29643403,
year = {2018},
author = {Wei, Z and Wang, J and Zhu, L and Wang, J and Zhu, G},
title = {Toxicity of enrofloxacin, copper and their interactions on soil microbial populations and ammonia-oxidizing archaea and bacteria.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {5828},
pmid = {29643403},
issn = {2045-2322},
abstract = {Enrofloxacin (EFX) is one of the most frequently used broad-spectrum veterinary drugs, and copper (Cu) is a heavy metal that could easily bind to certain antibiotic molecules. Hence EFX and Cu were chosen as representatives of antibiotics and heavy metals to explore the abundance and variation of soil microbial populations with a plate-counting technique, as well as the copy numbers of amoA gene in ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) by quantitative PCR methods in Argosols samples. Treatments of applied EFX (0.05, 0.20, 0.80 mmol/kg), Cu (1.60 mmol/kg) and combined EFX and Cu (at molar ratios of 1:32,1:8,1:2) exhibited various effects on different soil microorganisms. The toxicity of combined EFX and Cu was more strongly expressed on both soil microbial populations and amoA gene (AOA and AOB) compared to the EFX treatment alone, in most cases, time and dose effects were observed. With respect to the amoA gene, the AOA-amoA gene was more abundant than the AOB-amoA gene, and the ratio ranged from ~8 to ~11. Moreover, the interaction types of EFX and Cu were more likely to be antagonistic (64.29%) than synergistic (35.71%) on soil abundance and function, which may be related to the incubation time and the ratio of EFX to Cu in the soil.},
}
@article {pmid29636434,
year = {2018},
author = {Gilmour, CC and Bullock, AL and McBurney, A and Podar, M and Elias, DA},
title = {Robust Mercury Methylation across Diverse Methanogenic Archaea.},
journal = {mBio},
volume = {9},
number = {2},
pages = {},
pmid = {29636434},
issn = {2150-7511},
support = {R01 ES024284/ES/NIEHS NIH HHS/United States ; },
mesh = {Archaea/genetics/*metabolism ; Culture Media/chemistry ; Cysteine/metabolism ; Genes, Archaeal ; Mercuric Chloride/*metabolism ; Methane/*metabolism ; Methylation ; Methylmercury Compounds/*metabolism ; Sulfides/metabolism ; },
abstract = {Methylmercury (MeHg) production was compared among nine cultured methanogenic archaea that contain hgcAB, a gene pair that codes for mercury (Hg) methylation. The methanogens tested produced MeHg at inherently different rates, even when normalized to growth rate and Hg availability. Eight of the nine tested were capable of MeHg production greater than that of spent- and uninoculated-medium controls during batch culture growth. Methanococcoides methylutens, an hgcAB+ strain with a fused gene pair, was unable to produce more MeHg than controls. Maximal conversion of Hg to MeHg through a full batch culture growth cycle for each species (except M. methylutens) ranged from 2 to >50% of the added Hg(II) or between 0.2 and 17 pmol of MeHg/mg of protein. Three of the species produced >10% MeHg. The ability to produce MeHg was confirmed in several hgcAB+ methanogens that had not previously been tested (Methanocella paludicola SANAE, Methanocorpusculum bavaricum, Methanofollis liminatans GKZPZ, and Methanosphaerula palustris E1-9c). Maximal methylation was observed at low sulfide concentrations (<100 μM) and in the presence of 0.5 to 5 mM cysteine. For M. hollandica, the addition of up to 5 mM cysteine enhanced MeHg production and cell growth in a concentration-dependent manner. As observed for bacterial Hg methylators, sulfide inhibited MeHg production. An initial evaluation of sulfide and thiol impacts on bioavailability showed methanogens responding to Hg complexation in the same way as do Deltaproteobacteria The mercury methylation rates of several methanogens rival those of the better-studied Hg-methylating sulfate- and iron-reducing DeltaproteobacteriaIMPORTANCEArchaea, specifically methanogenic organisms, play a role in mercury methylation in nature, but their global importance to MeHg production and the subsequent risk to ecosystems are not known. Methanogenesis has been linked to Hg methylation in several natural habitats where methylmercury production incurs risk to people and ecosystems, including rice paddies and permafrost. In this study, we confirm that most methanogens carrying the hgcAB gene pair are capable of Hg methylation. We found that methylation rates vary inherently among hgcAB+ methanogens but that several species are capable of MeHg production at rates that rival those of the better-know Hg-methylating sulfate- and iron-reducing bacteria. Methanogens may need to be considered equally with sulfate and iron reducers in evaluations of MeHg production in nature.},
}
@article {pmid29631688,
year = {2018},
author = {Khallef, S and Lestini, R and Myllykallio, H and Houali, K},
title = {Isolation and identification of two extremely halophilic archaea from sebkhas in the Algerian Sahara.},
journal = {Cellular and molecular biology (Noisy-le-Grand, France)},
volume = {64},
number = {4},
pages = {83-91},
pmid = {29631688},
issn = {1165-158X},
mesh = {Africa, Northern ; Algeria ; DNA, Archaeal/*genetics ; Halobacteriaceae/classification/drug effects/genetics/*isolation &amp; purification ; Halorubrum/classification/drug effects/genetics/*isolation &amp; purification ; Hydrogen-Ion Concentration ; Lakes/*microbiology ; RNA, Ribosomal, 16S/*genetics ; Salinity ; Sequence Analysis, DNA ; Sodium Chloride/pharmacology ; },
abstract = {In Algeria, many salt lakes are to be found spread from southern Tunisia up to the Atlas Mountains in northern Algeria. Oum Eraneb and Ain El beida sebkhas (salt lakes), are located in the Algerian Sahara. The aim of this study was to explore the diversity of the halobacteria in this type of habitats. The physicochemical properties of these shallow saline environments were examined and compared with other hypersaline and marine ecosystems. Both sites were relatively alkaline with a pH around 8.57- 8.74 and rich in salt at 13% and 16% (w/v) salinity for Oum Eraneb and Ain El beida, respectively, with dominant ions of sodium and chloride. The microbial approach revealed the presence of two halophilic archaea, strains JCM13561 and A33T in both explored sebkhas. Growth occurred between 10 and 25% (w/v) NaCl and the isolates grow optimally at 20% (w/v) NaCl. The pH range for growth was 6 to 9.5 with an optimum at pH 7.5 for the first strain and 7 to 9.5 with an optimum pH at 8.5-9 for the second strain. On the basis of 16S rRNA gene sequence analysis, strains JCM13561 and A33T were most closely related to Halorubrum litoreum and Natronorubrum bangense (99% and 96% similarity, respectively).},
}
@article {pmid29625978,
year = {2018},
author = {McGlynn, SE and Chadwick, GL and O'Neill, A and Mackey, M and Thor, A and Deerinck, TJ and Ellisman, MH and Orphan, VJ},
title = {Subgroup Characteristics of Marine Methane-Oxidizing ANME-2 Archaea and Their Syntrophic Partners as Revealed by Integrated Multimodal Analytical Microscopy.},
journal = {Applied and environmental microbiology},
volume = {84},
number = {11},
pages = {},
pmid = {29625978},
issn = {1098-5336},
support = {P41 GM103412/GM/NIGMS NIH HHS/United States ; },
abstract = {Phylogenetically diverse environmental ANME archaea and sulfate-reducing bacteria cooperatively catalyze the anaerobic oxidation of methane oxidation (AOM) in multicelled consortia within methane seep environments. To better understand these cells and their symbiotic associations, we applied a suite of electron microscopy approaches, including correlative fluorescence in situ hybridization-electron microscopy (FISH-EM), transmission electron microscopy (TEM), and serial block face scanning electron microscopy (SBEM) three-dimensional (3D) reconstructions. FISH-EM of methane seep-derived consortia revealed phylogenetic variability in terms of cell morphology, ultrastructure, and storage granules. Representatives of the ANME-2b clade, but not other ANME-2 groups, contained polyphosphate-like granules, while some bacteria associated with ANME-2a/2c contained two distinct phases of iron mineral chains resembling magnetosomes. 3D segmentation of two ANME-2 consortium types revealed cellular volumes of ANME and their symbiotic partners that were larger than previous estimates based on light microscopy. Polyphosphate-like granule-containing ANME (tentatively termed ANME-2b) were larger than both ANME with no granules and partner bacteria. This cell type was observed with up to 4 granules per cell, and the volume of the cell was larger in proportion to the number of granules inside it, but the percentage of the cell occupied by these granules did not vary with granule number. These results illuminate distinctions between ANME-2 archaeal lineages and partnering bacterial populations that are apparently unified in their ability to perform anaerobic methane oxidation.IMPORTANCE Methane oxidation in anaerobic environments can be accomplished by a number of archaeal groups, some of which live in syntrophic relationships with bacteria in structured consortia. Little is known of the distinguishing characteristics of these groups. Here, we applied imaging approaches to better understand the properties of these cells. We found unexpected morphological, structural, and volume variability of these uncultured groups by correlating fluorescence labeling of cells with electron microscopy observables.},
}
@article {pmid29622618,
year = {2018},
author = {Poehlein, A and Heym, D and Quitzke, V and Fersch, J and Daniel, R and Rother, M},
title = {Complete Genome Sequence of the Methanococcus maripaludis Type Strain JJ (DSM 2067), a Model for Selenoprotein Synthesis in Archaea.},
journal = {Genome announcements},
volume = {6},
number = {14},
pages = {},
pmid = {29622618},
issn = {2169-8287},
abstract = {Methanococcus maripaludis type strain JJ (DSM 2067) is an important organism because it serves as a model for primary energy metabolism and hydrogenotrophic methanogenesis and is amenable to genetic manipulation. The complete genome (1.7 Mb) harbors 1,815 predicted protein-encoding genes, including 9 encoding selenoproteins.},
}
@article {pmid29618058,
year = {2018},
author = {Feng, X and Sun, M and Han, W and Liang, YX and She, Q},
title = {A transcriptional factor B paralog functions as an activator to DNA damage-responsive expression in archaea.},
journal = {Nucleic acids research},
volume = {46},
number = {14},
pages = {7085-7096},
pmid = {29618058},
issn = {1362-4962},
mesh = {4-Nitroquinoline-1-oxide/pharmacology ; Archaeal Proteins/biosynthesis/chemistry/genetics/*metabolism ; Crenarchaeota/genetics ; DNA Damage ; *DNA Repair ; Evolution, Molecular ; Gene Deletion ; Promoter Regions, Genetic ; Protein Domains ; Sulfolobus/cytology/drug effects/*genetics/metabolism ; Transcription Factors/biosynthesis/chemistry/genetics/*metabolism ; Transcriptional Activation ; },
abstract = {Previously it was shown that UV irradiation induces a strong upregulation of tfb3 coding for a paralog of the archaeal transcriptional factor B (TFB) in Sulfolobus solfataricus, a crenarchaea. To investigate the function of this gene in DNA damage response (DDR), tfb3 was inactivated by gene deletion in Sulfolobus islandicus and the resulting Δtfb3 was more sensitive to DNA damage agents than the original strain. Transcriptome analysis revealed that a large set of genes show TFB3-dependent activation, including genes of the ups operon and ced system. Furthermore, the TFB3 protein was found to be associated with DDR gene promoters and functional dissection of TFB3 showed that the conserved Zn-ribbon and coiled-coil motif are essential for the activation. Together, the results indicated that TFB3 activates the expression of DDR genes by interaction with other transcriptional factors at the promoter regions of DDR genes to facilitate the formation of transcription initiation complex. Strikingly, TFB3 and Ced systems are present in a wide range of crenarchaea, suggesting that the Ced system function as a primary DNA damage repair mechanism in Crenarchaeota. Our findings further suggest that TFB3 and the concurrent TFB1 form a TFB3-dependent DNA damage-responsive circuit with their target genes, which is evolutionarily conserved in the major lineage of Archaea.},
}
@article {pmid29596428,
year = {2018},
author = {Da Cunha, V and Gaia, M and Nasir, A and Forterre, P},
title = {Asgard archaea do not close the debate about the universal tree of life topology.},
journal = {PLoS genetics},
volume = {14},
number = {3},
pages = {e1007215},
pmid = {29596428},
issn = {1553-7404},
mesh = {*Archaea ; *Eukaryota ; Euryarchaeota ; Phylogeny ; Prokaryotic Cells ; },
}
@article {pmid29596421,
year = {2018},
author = {Spang, A and Eme, L and Saw, JH and Caceres, EF and Zaremba-Niedzwiedzka, K and Lombard, J and Guy, L and Ettema, TJG},
title = {Asgard archaea are the closest prokaryotic relatives of eukaryotes.},
journal = {PLoS genetics},
volume = {14},
number = {3},
pages = {e1007080},
pmid = {29596421},
issn = {1553-7404},
mesh = {Archaea/*genetics ; Eukaryota/*genetics ; Euryarchaeota ; Genome, Archaeal ; Prokaryotic Cells ; },
}
@article {pmid29595162,
year = {2018},
author = {Kiadehi, MSH and Amoozegar, MA and Asad, S and Siroosi, M},
title = {Exploring the potential of halophilic archaea for the decolorization of azo dyes.},
journal = {Water science and technology : a journal of the International Association on Water Pollution Research},
volume = {77},
number = {5-6},
pages = {1602-1611},
doi = {10.2166/wst.2018.040},
pmid = {29595162},
issn = {0273-1223},
mesh = {Archaea/*metabolism ; Azo Compounds/*chemistry/*metabolism ; Biodegradation, Environmental ; Carbon ; Coloring Agents/chemistry/metabolism ; Coordination Complexes/chemistry ; Naphthalenesulfonates/chemistry ; Nitrogen ; Sodium Chloride ; Textile Industry ; Waste Disposal, Fluid ; },
abstract = {Azo dyes are being extensively used in textile industries, so finding a proper solution to decolorize them is of high importance. In order to find azo dye decolorizing strains among haloarchaea, which are well known for their tolerance to harsh environmental conditions, fifteen haloarchaeal strains were screened. Halogeometricum sp. strain A and Haloferax sp. strain B with the highest decolorization ability (95% and 91% for Remazol black B; both about 60% for Acid blue 161, respectively) were selected for further studies. It was shown that both strains were able to grow and decolorize the dye in a medium containing up to 5 M NaCl, with optimum decolorization activity at 2.5-3.4 M, pH 7, and a wide temperature range between 30 to 45 °C. Moreover, both strains were able to tolerate and decolorize up to 1,000 mg l-1 Remazol black B. Also, they were able to survive in 5,000 mg l-1 of the dye after 20 days' incubation. Glucose and yeast extract were found to be the best carbon and nitrogen sources in the decolorization medium for both strains. This is the first report studying decolorization of azo dyes using halophilic archaea.},
}
@article {pmid29573609,
year = {2018},
author = {Pillot, G and Frouin, E and Pasero, E and Godfroy, A and Combet-Blanc, Y and Davidson, S and Liebgott, PP},
title = {Specific enrichment of hyperthermophilic electroactive Archaea from deep-sea hydrothermal vent on electrically conductive support.},
journal = {Bioresource technology},
volume = {259},
number = {},
pages = {304-311},
doi = {10.1016/j.biortech.2018.03.053},
pmid = {29573609},
issn = {1873-2976},
mesh = {*Archaea ; Atlantic Ocean ; Bacteria ; Electrolysis ; *Hydrothermal Vents ; Phylogeny ; RNA, Ribosomal, 16S ; Seawater ; },
abstract = {While more and more investigations are done to study hyperthermophilic exoelectrogenic communities from environments, none have been performed yet on deep-sea hydrothermal vent. Samples of black smoker chimney from Rainbow site on the Atlantic mid-oceanic ridge have been harvested for enriching exoelectrogens in microbial electrolysis cells under hyperthermophilic (80 °C) condition. Two enrichments were performed in a BioElectrochemical System specially designed: one from direct inoculation of crushed chimney and the other one from inoculation of a pre-cultivation on iron (III) oxide. In both experiments, a current production was observed from 2.4 A/m2 to 5.8 A/m2 with a set anode potential of -0.110 V vs Ag/AgCl. Taxonomic affiliation of the exoelectrogen communities obtained on the electrode exhibited a specific enrichment of Archaea belonging to Thermococcales and Archeoglobales orders, even when both inocula were dominated by Bacteria.},
}
@article {pmid29522733,
year = {2018},
author = {},
title = {Extreme Excitement about Archaea.},
journal = {Cell},
volume = {172},
number = {6},
pages = {1153-1154},
doi = {10.1016/j.cell.2018.02.038},
pmid = {29522733},
issn = {1097-4172},
}
@article {pmid29510582,
year = {2018},
author = {Gelsinger, DR and DiRuggiero, J},
title = {The Non-Coding Regulatory RNA Revolution in Archaea.},
journal = {Genes},
volume = {9},
number = {3},
pages = {},
pmid = {29510582},
issn = {2073-4425},
support = {T32 GM007231/GM/NIGMS NIH HHS/United States ; },
abstract = {Small non-coding RNAs (sRNAs) are ubiquitously found in the three domains of life playing large-scale roles in gene regulation, transposable element silencing and defense against foreign elements. While a substantial body of experimental work has been done to uncover function of sRNAs in Bacteria and Eukarya, the functional roles of sRNAs in Archaea are still poorly understood. Recently, high throughput studies using RNA-sequencing revealed that sRNAs are broadly expressed in the Archaea, comprising thousands of transcripts within the transcriptome during non-challenged and stressed conditions. Antisense sRNAs, which overlap a portion of a gene on the opposite strand (cis-acting), are the most abundantly expressed non-coding RNAs and they can be classified based on their binding patterns to mRNAs (3' untranslated region (UTR), 5' UTR, CDS-binding). These antisense sRNAs target many genes and pathways, suggesting extensive roles in gene regulation. Intergenic sRNAs are less abundantly expressed and their targets are difficult to find because of a lack of complete overlap between sRNAs and target mRNAs (trans-acting). While many sRNAs have been validated experimentally, a regulatory role has only been reported for very few of them. Further work is needed to elucidate sRNA-RNA binding mechanisms, the molecular determinants of sRNA-mediated regulation, whether protein components are involved and how sRNAs integrate with complex regulatory networks.},
}
@article {pmid29507381,
year = {2018},
author = {Burns, JA and Pittis, AA and Kim, E},
title = {Publisher Correction: Gene-based predictive models of trophic modes suggest Asgard archaea are not phagocytotic.},
journal = {Nature ecology &amp; evolution},
volume = {2},
number = {4},
pages = {751},
doi = {10.1038/s41559-018-0520-8},
pmid = {29507381},
issn = {2397-334X},
abstract = {In the version of this Article originally published, question marks appeared in Table 1; they should have been tick marks. This has now been corrected in all versions of the Article.},
}
@article {pmid29497404,
year = {2018},
author = {Liu, J and Yu, Z and Yao, Q and Sui, Y and Shi, Y and Chu, H and Tang, C and Franks, AE and Jin, J and Liu, X and Wang, G},
title = {Ammonia-Oxidizing Archaea Show More Distinct Biogeographic Distribution Patterns than Ammonia-Oxidizing Bacteria across the Black Soil Zone of Northeast China.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {171},
pmid = {29497404},
issn = {1664-302X},
abstract = {Black soils (Mollisols) of northeast China are highly productive and agriculturally important for food production. Ammonia-oxidizing microbes play an important role in N cycling in the black soils. However, the information related to the composition and distribution of ammonia-oxidizing microbes in the black soils has not yet been addressed. In this study, we used the amoA gene to quantify the abundance and community composition of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) across the black soil zone. The amoA abundance of AOA was remarkably larger than that of AOB, with ratios of AOA/AOB in the range from 3.1 to 91.0 across all soil samples. The abundance of AOA amoA was positively correlated with total soil C content (p < 0.001) but not with soil pH (p > 0.05). In contrast, the abundance of AOB amoA positively correlated with soil pH (p = 0.009) but not with total soil C. Alpha diversity of AOA did not correlate with any soil parameter, however, alpha diversity of AOB was affected by multiple soil factors, such as soil pH, total P, N, and C, available K content, and soil water content. Canonical correspondence analysis indicated that the AOA community was mainly affected by the sampling latitude, followed by soil pH, total P and C; while the AOB community was mainly determined by soil pH, as well as total P, C and N, water content, and sampling latitude, which highlighted that the AOA community was more geographically distributed in the black soil zone of northeast China than AOB community. In addition, the pairwise analyses showed that the potential nitrification rate (PNR) was not correlated with alpha diversity but weakly positively with the abundance of the AOA community (p = 0.048), whereas PNR significantly correlated positively with the richness (p = 0.003), diversity (p = 0.001) and abundance (p < 0.001) of the AOB community, which suggested that AOB community might make a greater contribution to nitrification than AOA community in the black soils when ammonium is readily available.},
}
@article {pmid29478661,
year = {2018},
author = {Ma, W and Sun, J and Li, Y and Lun, X and Shan, D and Nie, C and Liu, M},
title = {17α-Ethynylestradiol biodegradation in different river-based groundwater recharge modes with reclaimed water and degradation-associated community structure of bacteria and archaea.},
journal = {Journal of environmental sciences (China)},
volume = {64},
number = {},
pages = {51-61},
doi = {10.1016/j.jes.2016.11.022},
pmid = {29478661},
issn = {1001-0742},
mesh = {Archaea/physiology ; Bacteria/metabolism ; Ethinyl Estradiol/analysis/*metabolism ; Groundwater/chemistry/*microbiology ; Rivers/chemistry/*microbiology ; Water Microbiology ; Water Pollutants, Chemical/analysis/*metabolism ; },
abstract = {This study investigated 17α-ethynylestradiol (EE2) biodegradation process and primary metabolic pathways associated with community structures of microorganism during groundwater recharge using reclaimed water. The attenuation rate is 1.58 times higher in wetting and drying alternative recharge (WDAR) than in continual recharge (CR). The primary biotransformation pathways of EE2 in WDAR system began with the oxidation of C-17 on ring D to form a ketone group, and D-ring was subsequently hydroxylated and cleaved. In the CR system, the metabolic pathway changed from the oxidation of C-17 on ring D to hydroxylation of C-4 on ring A, and ring A or B subsequently cleaved; this transition was related to DO, and the microbial community structure. Four hundred fifty four pyrosequencing of 16s rRNA genes indicated that the bacterial communities in the upper layer of the WDAR system were more diverse than those found in the bottom layer of the CR system; this result was reversed for archaea. Unweighted UniFrac and taxonomic analyses were conducted to relate the change in bacterial community structure to the metabolic pathway. Microorganism community diversity and structure were related to the concentrations of dissolved oxygen, EE2 and its intermediates in the system. Five known bacterial classes and one known archaeal class, five major bacterial genera and one major archaeal genus might be involved in EE2 degradation. The findings of this study provide an understanding of EE2 biodegradation in groundwater recharge areas under different recharging modes and can facilitate the prediction of the fate of EE2 in underground aquifers.},
}
@article {pmid29472326,
year = {2018},
author = {Oger, PM},
title = {Complete Genome Sequences of 11 Type Species from the Thermococcus Genus of Hyperthermophilic and Piezophilic Archaea.},
journal = {Genome announcements},
volume = {6},
number = {8},
pages = {},
pmid = {29472326},
issn = {2169-8287},
abstract = {We report here the genome sequences of the type strains of the species Thermococcus barossii, T. celer, T. chitonophagus, T. gorgonarius, T. pacificus, T. peptonophilus, T. profundus, T. radiotolerans, T. siculi, and T. thioreducens, as well as the prototype of a possible type strain of a novel Thermococcus species, strain P6.},
}
@article {pmid29465796,
year = {2018},
author = {Abdul Halim, MF and Rodriguez, R and Stoltzfus, JD and Duggin, IG and Pohlschroder, M},
title = {Conserved residues are critical for Haloferax volcanii archaeosortase catalytic activity: Implications for convergent evolution of the catalytic mechanisms of non-homologous sortases from archaea and bacteria.},
journal = {Molecular microbiology},
volume = {108},
number = {3},
pages = {276-287},
doi = {10.1111/mmi.13935},
pmid = {29465796},
issn = {1365-2958},
support = {R25 GM071745/GM/NIGMS NIH HHS/United States ; },
mesh = {Amino Acid Sequence ; Aminoacyltransferases/genetics/*metabolism ; Archaea/genetics ; Archaeal Proteins/metabolism ; Arginine/metabolism ; Bacteria/genetics ; Bacterial Proteins/genetics/metabolism ; Biological Evolution ; Catalysis ; Catalytic Domain ; Conserved Sequence/genetics ; Cysteine/metabolism ; Cysteine Endopeptidases/genetics/*metabolism ; Evolution, Molecular ; Haloferax volcanii/*metabolism ; Histidine/metabolism ; Protein Processing, Post-Translational ; },
abstract = {Proper protein anchoring is key to the biogenesis of prokaryotic cell surfaces, dynamic, resilient structures that play crucial roles in various cell processes. A novel surface protein anchoring mechanism in Haloferax volcanii depends upon the peptidase archaeosortase A (ArtA) processing C-termini of substrates containing C-terminal tripartite structures and anchoring mature substrates to the cell membrane via intercalation of lipid-modified C-terminal amino acid residues. While this membrane protein lacks clear homology to soluble sortase transpeptidases of Gram-positive bacteria, which also process C-termini of substrates whose C-terminal tripartite structures resemble those of ArtA substrates, archaeosortases do contain conserved cysteine, arginine and arginine/histidine/asparagine residues, reminiscent of His-Cys-Arg residues of sortase catalytic sites. The study presented here shows that ArtAWT -GFP expressed in trans complements ΔartA growth and motility phenotypes, while alanine substitution mutants, Cys173 (C173A), Arg214 (R214A) or Arg253 (R253A), and the serine substitution mutant for Cys173 (C173S), fail to complement these phenotypes. Consistent with sortase active site replacement mutants, ArtAC173A -GFP, ArtAC173S -GFP and ArtAR214A -GFP cannot process substrates, while replacement of the third residue, ArtAR253A -GFP retains some processing activity. These findings support the view that similarities between certain aspects of the structures and functions of the sortases and archaeosortases are the result of convergent evolution.},
}
@article {pmid29459706,
year = {2018},
author = {Burns, JA and Pittis, AA and Kim, E},
title = {Gene-based predictive models of trophic modes suggest Asgard archaea are not phagocytotic.},
journal = {Nature ecology &amp; evolution},
volume = {2},
number = {4},
pages = {697-704},
doi = {10.1038/s41559-018-0477-7},
pmid = {29459706},
issn = {2397-334X},
mesh = {Archaea/classification/*physiology ; *Models, Genetic ; *Phagocytosis ; Phylogeny ; },
abstract = {With the current explosion of genomic data, there is a greater need to draw inference on phenotypic information based on DNA sequence alone. We considered complete genomes from 35 diverse eukaryotic lineages, and discovered sets of proteins predictive of trophic mode, including a set of 485 proteins that are enriched among phagocytotic eukaryotes (organisms that internalize large particles). Our model is also predictive of other aspects of trophic mode, including photosynthesis and the ability to synthesize a set of organic compounds needed for growth (prototrophy for those molecules). We applied our model to the Asgard archaea, a group of uncultured microorganisms that show close affinities to eukaryotes, to test whether the organisms are capable of phagocytosis, a phenotypic trait often considered a prerequisite for mitochondrial acquisition. Our analyses suggest that members of the Asgard archaea-despite having some eukaryote-specific protein families not found in other prokaryotes-do not use phagocytosis. Moreover, our data suggest that the process of phagocytosis arose from a combination of both archaeal and bacterial components, but also required additional eukaryote-specific innovations.},
}
@article {pmid29459337,
year = {2018},
author = {Yan, L and Wang, G and Ai, S and Huo, Z and Wang, Y and Gu, JD and Wang, W},
title = {Abundance of ammonia-oxidizing bacteria and archaea under different ventilation strategies during cattle manure composting.},
journal = {Journal of environmental management},
volume = {212},
number = {},
pages = {375-383},
doi = {10.1016/j.jenvman.2018.02.032},
pmid = {29459337},
issn = {1095-8630},
mesh = {Ammonia ; Animals ; Archaea/*growth &amp; development ; Bacteria/*growth &amp; development ; Cattle ; *Composting ; *Manure ; Oxidation-Reduction ; Phylogeny ; Soil Microbiology ; Ventilation ; },
abstract = {Composting of cattle manure was conducted under four ventilation strategies, i.e., no-aeration (A-00), continuous aeration (B-44), non-aeration for 14 d and then aeration for 42 d (C-04), aeration for 14 d and then no-aeration for 42 d (D-40). Physicochemical parameters and potential ammonia oxidation (PAO) indicated that continuous and intermittent ventilation provide favourable conditions for ammonia-oxidizing bacteria (AOB) and archaea (AOA) to oxidize ammonia. Quantitative PCR (qPCR) analysis showed AOB amoA gene abundance of all treatments on every sampling day ranged from 2.25 × 105 to 2.76 × 109copies/g, was significantly lower than that of archaeal amoA gene from 2.71 × 108 to 9.05 × 1011copies/g. There was also a significantly positive relationship between PAO rates and AOB (r2 ≥ 0.066, p < 0.05) and AOA (r2 ≥ 0.300, p < 0.05) abundance. These data suggested that ammonia oxidation is driven by both AOA and AOB in cattle manure composting.},
}
@article {pmid29459210,
year = {2018},
author = {Araujo, ASF and Mendes, LW and Bezerra, WM and Nunes, LAPL and Lyra, MDCCP and Figueiredo, MDVB and Melo, VMM},
title = {Archaea diversity in vegetation gradients from the Brazilian Cerrado.},
journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]},
volume = {49},
number = {3},
pages = {522-528},
pmid = {29459210},
issn = {1678-4405},
mesh = {Archaea/classification/genetics/growth &amp; development/*isolation &amp; purification ; Biodiversity ; Brazil ; Phylogeny ; Plant Development ; Plants/classification/*microbiology ; Soil/chemistry ; *Soil Microbiology ; },
abstract = {We used 16S rRNA sequencing to assess the archaeal communities across a gradient of Cerrado. The archaeal communities differed across the gradient. Crenarcheota was the most abundant phyla, with Nitrosphaerales and NRPJ as the predominant classes. Euryachaeota was also found across the Cerrado gradient, including the classes Metanocellales and Methanomassiliicoccaceae.},
}
@article {pmid29458865,
year = {2018},
author = {Menasria, T and Aguilera, M and Hocine, H and Benammar, L and Ayachi, A and Si Bachir, A and Dekak, A and Monteoliva-Sánchez, M},
title = {Diversity and bioprospecting of extremely halophilic archaea isolated from Algerian arid and semi-arid wetland ecosystems for halophilic-active hydrolytic enzymes.},
journal = {Microbiological research},
volume = {207},
number = {},
pages = {289-298},
doi = {10.1016/j.micres.2017.12.011},
pmid = {29458865},
issn = {1618-0623},
mesh = {Algeria ; Biodiversity ; Esterases/*genetics ; Halobacteriaceae/*classification/*enzymology/genetics/isolation &amp; purification ; Lakes/chemistry ; Peptide Hydrolases/*genetics ; RNA, Ribosomal, 16S/genetics ; Salinity ; Sodium Chloride/analysis ; Wetlands ; },
abstract = {The diversity of haloarchaea associated with different dry salt lakes in northeastern Algeria was investigated together with their potential of hydrolytic enzyme production. A total of 68 aerobic halophilic archaea were isolated from saline sediments. Based on the 16S rRNA gene sequencing, the isolates were assigned to seven phylotypes within the class Halobacteria, namely Haloarcula, Halococcus, Haloferax, Halogeometricum, Haloterrigena, Natrialba, and Natrinema. The results showed that Haloferax group was found to be dominant in all samples (30 isolates) (44%) with high diversity, followed by Halococcus spp. (13%) (9 isolates). All phylotypes are extreme halophiles and thermotolerant with the ability to grow at temperatures up to 48 °C. In addition, the screening for extracellular halophilic enzymes showed that 89.7% of the isolates were able to produce at least two types of the screened enzymes. The strains producing esterase, gelatinase, inulinase, cellulase and protease activities were the most diverse functional group. These data showed an abundant and diverse haloarchaeal community, detected in Algerian wetland ecosystems, presenting a promising source of molecules with important biotechnological applications.},
}
@article {pmid29456526,
year = {2018},
author = {He, H and Zhen, Y and Mi, T and Fu, L and Yu, Z},
title = {Ammonia-Oxidizing Archaea and Bacteria Differentially Contribute to Ammonia Oxidation in Sediments from Adjacent Waters of Rushan Bay, China.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {116},
pmid = {29456526},
issn = {1664-302X},
abstract = {Ammonia oxidation plays a significant role in the nitrogen cycle in marine sediments. Ammonia-oxidizing archaea (AOA) and bacteria (AOB) are the key contributors to ammonia oxidation, and their relative contribution to this process is one of the most important issues related to the nitrogen cycle in the ocean. In this study, the differential contributions of AOA and AOB to ammonia oxidation in surface sediments from adjacent waters of Rushan Bay were studied based on the ammonia monooxygenase (amoA) gene. Molecular biology techniques were used to analyze ammonia oxidizers' community characteristics, and potential nitrification incubation was applied to understand the ammonia oxidizers' community activity. The objective was to determine the community structure and activity of AOA and AOB in surface sediments from adjacent waters of Rushan Bay and to discuss the different contributions of AOA and AOB to ammonia oxidation during summer and winter seasons in the studied area. Pyrosequencing analysis revealed that the diversity of AOA was higher than that of AOB. The majority of AOA and AOB clustered into Nitrosopumilus and Nitrosospira, respectively, indicating that the Nitrosopumilus group and Nitrosospira groups may be more adaptable in studied sediments. The AOA community was closely correlated to temperature, salinity and ammonium concentration, whereas the AOB community showed a stronger correlation with temperature, chlorophyll-a content (chla) and nitrite concentration. qPCR results showed that both the abundance and the transcript abundance of AOA was consistently greater than that of AOB. AOA and AOB differentially contributed to ammonia oxidation in different seasons. AOB occupied the dominant position in mediating ammonia oxidation during summer, while AOA might play a dominant role in ammonia oxidation during winter.},
}
@article {pmid29446847,
year = {2018},
author = {Řezanka, T and Kolouchová, I and Gharwalová, L and Palyzová, A and Sigler, K},
title = {Lipidomic Analysis: From Archaea to Mammals.},
journal = {Lipids},
volume = {53},
number = {1},
pages = {5-25},
doi = {10.1002/lipd.12001},
pmid = {29446847},
issn = {1558-9307},
mesh = {Animals ; Archaea/chemistry/*genetics ; Chromatography, High Pressure Liquid ; Chromatography, Liquid ; Humans ; Lipid Metabolism/*genetics ; Lipids/chemistry/*genetics ; Mammals/genetics ; Metabolomics/*methods ; },
abstract = {Lipids are among the most important organic compounds found in all living cells, from primitive archaebacteria to flowering plants or mammalian cells. They form part of cell walls and constitute cell storage material. Their biosynthesis and metabolism play key roles in faraway topics such as biofuel production (third-generation biofuels produced by microorganisms, e.g. algae) and human diseases such as adrenoleukodystrophy, Zellweger syndrome, or Refsum disease. Current lipidomic analysis requires fast and accurate processing of samples and especially their characterization. Because the number of possible lipids and, more specifically, molecular species of lipids is of the order of hundreds to thousands, it is necessary to process huge amounts of data in a short time. There are two basic approaches to lipidomic analysis: shotgun and liquid chromatography-mass spectometry. Both methods have their pros and cons. This review deals with lipidomics not according to the type of ionization or the lipid classes analyzed but according to the types of samples (organisms) under study. Thus, it is divided into lipidomic analysis of archaebacteria, bacteria, yeast, fungi, algae, plants, and animals.},
}
@article {pmid29429071,
year = {2018},
author = {Huang, Z and Jiang, Y and Song, X and Hallerman, E and Peng, L and Dong, D and Ma, T and Zhai, J and Li, W},
title = {Ammonia-oxidizing bacteria and archaea within biofilters of a commercial recirculating marine aquaculture system.},
journal = {AMB Express},
volume = {8},
number = {1},
pages = {17},
pmid = {29429071},
issn = {2191-0855},
support = {31502212//National Natural Science Foundation of China/ ; },
abstract = {While biofilters are widely used to metabolize ammonia and other wastes in marine recirculating aquaculture systems, the ammonia-oxidizing bacterial and archaeal communities have not been characterized across a diversity of production systems. Using a metagenomics approach, we characterized the ammonia-oxidizing microbiological community of biofilters in a commercial recirculating marine aquaculture system producing hybrid grouper (Epinephelus lanceolatus × E. fuscoguttatus). Cloning and sequencing of the amoA gene showed that nitrifying bacteria included Nitrosomonas europea, N. stercoris, N. cryotolerans, N. eutropha, N. estuarii, eight strains of N. marina, and 15 strains not associated with described species. Nitrifying archaea included eight strains of Nitrosopumilus maritimus, N. koreensis, N. piranensis, N. adriaticus, undescribed congeners, and other undescribed archaea. The species composition of the bacterial and especially the archaeal communities was beyond that yet reported for aquaculture biofilters. While ammonia flux through the respective communities has yet to be estimated, the diverse environmental adaptations of the bacterial and archaeal communities suggest resilience of function under a range of environmental conditions.},
}
@article {pmid29406516,
year = {2018},
author = {Bowers, RM and Kyrpides, NC and Stepanauskas, R and Harmon-Smith, M and Doud, D and Reddy, TBK and Schulz, F and Jarett, J and Rivers, AR and Eloe-Fadrosh, EA and Tringe, SG and Ivanova, NN and Copeland, A and Clum, A and Becraft, ED and Malmstrom, RR and Birren, B and Podar, M and Bork, P and Weinstock, GM and Garrity, GM and Dodsworth, JA and Yooseph, S and Sutton, G and Glöckner, FO and Gilbert, JA and Nelson, WC and Hallam, SJ and Jungbluth, SP and Ettema, TJG and Tighe, S and Konstantinidis, KT and Liu, WT and Baker, BJ and Rattei, T and Eisen, JA and Hedlund, B and McMahon, KD and Fierer, N and Knight, R and Finn, R and Cochrane, G and Karsch-Mizrachi, I and Tyson, GW and Rinke, C and , and Lapidus, A and Meyer, F and Yilmaz, P and Parks, DH and Eren, AM and Schriml, L and Banfield, JF and Hugenholtz, P and Woyke, T},
title = {Corrigendum: Minimum information about a single amplified genome (MISAG) and a metagenome-assembled genome (MIMAG) of bacteria and archaea.},
journal = {Nature biotechnology},
volume = {36},
number = {2},
pages = {196},
pmid = {29406516},
issn = {1546-1696},
}
@article {pmid29401401,
year = {2018},
author = {Brzezińska-Błaszczyk, E and Pawłowska, E and Płoszaj, T and Witas, H and Godzik, U and Agier, J},
title = {Presence of archaea and selected bacteria in infected root canal systems.},
journal = {Canadian journal of microbiology},
volume = {64},
number = {5},
pages = {317-326},
doi = {10.1139/cjm-2017-0531},
pmid = {29401401},
issn = {1480-3275},
mesh = {Adult ; Archaea/*genetics ; Bacterial Infections/*microbiology ; Bacteroidaceae/*genetics ; DNA, Bacterial/genetics ; Dental Pulp Cavity/microbiology ; Dental Pulp Necrosis/*microbiology ; Female ; Humans ; Male ; Phylogeny ; RNA, Ribosomal, 16S/genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Young Adult ; },
abstract = {Infections of the root canal have polymicrobial etiology. The main group of microflora in the infected pulp is bacteria. There is limited data that archaea may be present in infected pulp tissue. The aim of this study was to check the prevalence of archaea in necrotic root canal samples obtained from patients with primary or post-treatment infection. The prevalence of selected bacteria species (Prevotella intermedia, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Synergistes sp.) in necrotic samples was evaluated as well. Sixty-four samples from root canal were collected for DNA and RNA extraction. A PCR assay based on the 16S rRNA gene was used to determine the presence of archaea and selected bacteria. Of the 64 samples, 6 were analyzed by semiquantitative reverse transcription PCR to estimate expression profiles of 16S rRNA, and another 9 were selected for direct sequencing. Archaea were detected in 48.4% samples. Statistical analysis indicated a negative association in coexistence between archaea and Treponema denticola (P < 0.05; Pearson's χ2 test). The main representative of the Archaea domain found in infected pulp tissue was Methanobrevibacter oralis. Archaea 16S rRNA gene expression was significantly lower than Synergistes sp., Porphyromonas gingivalis, and Tannerella forsythia (P < 0.05; Student's t test). Thus, it can be hypothesized that archaea may participate in the endodontic microbial community.},
}
@article {pmid29396546,
year = {2018},
author = {Gonzalez-Martinez, A and Sihvonen, M and Muñoz-Palazon, B and Rodriguez-Sanchez, A and Mikola, A and Vahala, R},
title = {Microbial ecology of full-scale wastewater treatment systems in the Polar Arctic Circle: Archaea, Bacteria and Fungi.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {2208},
pmid = {29396546},
issn = {2045-2322},
mesh = {Archaea/classification/genetics/*isolation &amp; purification ; Arctic Regions ; Bacteria/classification/genetics/*isolation &amp; purification ; Bioreactors/*microbiology ; *Biota ; Finland ; Fungi/classification/genetics/*isolation &amp; purification ; Metagenomics ; Real-Time Polymerase Chain Reaction ; Sequence Analysis, DNA ; Sewage/microbiology ; Waste Water/*microbiology ; Water Purification ; },
abstract = {Seven full-scale biological wastewater treatment systems located in the Polar Arctic Circle region in Finland were investigated to determine their Archaea, Bacteria and Fungi community structure, and their relationship with the operational conditions of the bioreactors by the means of quantitative PCR, massive parallel sequencing and multivariate redundancy analysis. The results showed dominance of Archaea and Bacteria members in the bioreactors. The activated sludge systems showed strong selection of Bacteria but not for Archaea and Fungi, as suggested by diversity analyses. Core OTUs in influent and bioreactors were classified as Methanobrevibacter, Methanosarcina, Terrestrial Group Thaumarchaeota and unclassified Euryarchaeota member for Archaea; Trichococcus, Leptotrichiaceae and Comamonadaceae family, and Methylorosula for Bacteria and Trichosporonaceae family for Fungi. All influents shared core OTUs in all domains, but in bioreactors this did not occur for Bacteria. Oligotype structure of core OTUs showed several ubiquitous Fungi oligotypes as dominant in sewage and bioreactors. Multivariate redundancy analyses showed that the majority of core OTUs were related to organic matter and nutrients removal. Also, there was evidence of competition among Archaea and Fungi core OTUs, while all Bacteria OTUs were positively correlated among them. The results obtained highlighted interesting features of extremely cold temperature bioreactors.},
}
@article {pmid29390107,
year = {2018},
author = {Seyler, LM and McGuinness, LR and Gilbert, JA and Biddle, JF and Gong, D and Kerkhof, LJ},
title = {Discerning autotrophy, mixotrophy and heterotrophy in marine TACK archaea from the North Atlantic.},
journal = {FEMS microbiology ecology},
volume = {94},
number = {3},
pages = {},
doi = {10.1093/femsec/fiy014},
pmid = {29390107},
issn = {1574-6941},
mesh = {Archaea/genetics/isolation &amp; purification/*metabolism ; Atlantic Ocean ; Autotrophic Processes ; Carbon/metabolism ; Carbon Cycle ; Heterotrophic Processes ; Phylogeny ; Seawater/*microbiology ; },
abstract = {DNA stable isotope probing (SIP) was used to track the uptake of organic and inorganic carbon sources for TACK archaea (Thaumarchaeota/Aigarchaeota/Crenarchaeota/Korarchaeota) on a cruise of opportunity in the North Atlantic. Due to water limitations, duplicate samples from the deep photic (60-115 m), the mesopelagic zones (local oxygen minimum; 215-835 m) and the bathypelagic zone (2085-2835 m) were amended with various combinations of 12C- or 13C-acetate/urea/bicarbonate to assess cellular carbon acquisition. The SIP results indicated the majority of TACK archaeal operational taxonomic units (OTUs) incorporated 13C from acetate and/or urea into newly synthesized DNA within 48 h. A small fraction (16%) of the OTUs, often representing the most dominant members of the archaeal community, were able to incorporate bicarbonate in addition to organic substrates. Only two TACK archaeal OTUs were found to incorporate bicarbonate but not urea or acetate. These results further demonstrate the utility of SIP to elucidate the metabolic capability of mesothermal archaea in distinct oceanic settings and suggest that TACK archaea play a role in organic carbon recycling in the mid-depth to deep ocean.},
}
@article {pmid29371667,
year = {2018},
author = {Li, M and Wei, G and Shi, W and Sun, Z and Li, H and Wang, X and Gao, Z},
title = {Distinct distribution patterns of ammonia-oxidizing archaea and bacteria in sediment and water column of the Yellow River estuary.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {1584},
pmid = {29371667},
issn = {2045-2322},
mesh = {Ammonia/*metabolism ; Ammonium Compounds/analysis ; Archaea/*classification/isolation &amp; purification/metabolism ; Bacteria/*classification/isolation &amp; purification/metabolism ; *Biota ; Carbon/analysis ; China ; *Estuaries ; Geologic Sediments/chemistry/*microbiology ; Oxidation-Reduction ; Rivers/*microbiology ; Water/chemistry ; },
abstract = {Ammonia oxidation is a critical process of estuarine nitrogen cycling involving ammonia-oxidizing archaea (AOA) and bacteria (AOB). However, the distribution patterns of ammonia-oxidizing microorganisms (AOMs) between different habitats in the same area remain unclear. The present study investigated the AOMs' abundance and community compositions in both sediment and water habitats of the Yellow River estuary. Quantitative PCR (qPCR) revealed that AOA showed significant higher abundance than AOB both in sediment and water samples. AOA and AOB abundance distribution trends were consistent in sediment but distinct in water along the sampling sites. Clone library-based analyses showed that AOA sequences were affiliated with Nitrososphaera, Nitrosopumilus and Nitrosotalea clusters. Generally, Nitrososphaera was predominant in sediment, while Nitrosopumilus and Nitrosotalea dominated in water column. AOB sequences were classified into genera Nitrosospira and Nitrosomonas, and Nitrosospira dominated in both habitats. Principal coordinate analysis (PCoA) also indicated AOA community structures exhibited significant differences between two habitats, while AOB were not. Ammonium and carbon contents were the potential key factors to influence AOMs' abundance and compositions in sediment, while no measured variables were determined to have major influences on communities in water habitat. These findings increase the understanding of the AOMs' distribution patterns in estuarine ecosystems.},
}
@article {pmid29357055,
year = {2017},
author = {Bell, SD},
title = {Initiation of DNA Replication in the Archaea.},
journal = {Advances in experimental medicine and biology},
volume = {1042},
number = {},
pages = {99-115},
doi = {10.1007/978-981-10-6955-0_5},
pmid = {29357055},
issn = {0065-2598},
mesh = {Archaea/*genetics/metabolism ; Archaeal Proteins/metabolism/physiology ; Chromosomes/metabolism ; DNA Replication/*physiology ; *Replication Origin/genetics ; },
abstract = {Organisms within the archaeal domain of life possess a simplified version of the eukaryotic DNA replication machinery. While some archaea possess a bacterial-like mode of DNA replication with single origins of replication per chromosome, the majority of species characterized to date possess chromosomes with multiple replication origins. Genetic, structural, and biochemical studies have revealed the nature of archaeal origin specification. Recent work has begun to shed light on the mechanisms of replication initiation in these organisms.},
}
@article {pmid29354356,
year = {2018},
author = {Singh, A and Singh, AK},
title = {Isolation, characterization and exploring biotechnological potential of halophilic archaea from salterns of western India.},
journal = {3 Biotech},
volume = {8},
number = {1},
pages = {45},
pmid = {29354356},
issn = {2190-572X},
abstract = {Thirteen halophilic archaea were isolated from Kandla and Bhayander salt pans. These isolates were grouped into three different genera Halobacterium, Haloferax and Haloarcula based on morphological and biochemical characterization, polar lipid analysis, Amplified 16S rDNA restriction analysis (ARDRA) and 16S rDNA sequence analysis. Biochemical characterization suggested the ability of isolates to produce protease, amylase and poly-hydroxybutyrate (PHB) indicating their biotechnological potential. The isolates were further screened for the amount of extracellular protease produced. Halobacterium sp. SP1(1) showed significant protease production compared to other isolates. Protease producing ability of the isolate was influenced by several factors such as NaCl concentration, type of protein source, metal ions and surfactants, and presence of amino acid supplements in the production medium. Soybean flour, FeCl3 and dicotylsulfosuccinate were found to increase protease production by 2.36, 1.54 and 1.26 folds, respectively compared to production in basal medium. Effect of organic solvents used in paints (n-decane, n-undecane and n-dodecane) was also investigated on protease production by the isolate. Protease production by Halobacterium sp. SP1(1) was enhanced by 1.2 folds in presence of n-decane compared to control. Furthermore, the ability of isolate to hydrolyse fish protein was investigated using three different edible fishes (Pomfret, Flat fish and Seer fish) as sole protein source. Pomfret was found to be a good protein source for protease production by the isolate. These results revealed that Halobacterium sp. SP1(1) may have potential for paint-based antifouling coating preparations and fish sauce preparation by virtue of its extracellular protease.},
}
@article {pmid29335805,
year = {2018},
author = {Oren, A and Hirschberg, J and Mann, V and Jehlička, J},
title = {Effects of nicotine on the biosynthesis of carotenoids in halophilic Archaea (class Halobacteria): an HPLC and Raman spectroscopy study.},
journal = {Extremophiles : life under extreme conditions},
volume = {22},
number = {3},
pages = {359-366},
pmid = {29335805},
issn = {1433-4909},
support = {2221/15//Israel Science Foundation/ ; 850/13//Israel Science Foundation/ ; 17-04270S//Grantová Agentura České Republiky/ ; },
mesh = {Carotenoids/analysis/*biosynthesis ; Euryarchaeota/chemistry/*drug effects/metabolism ; Nicotine/*pharmacology ; Nicotinic Agonists/*pharmacology ; },
abstract = {Nicotine has a profound influence on the carotenoid metabolism in halophilic Archaea of the class Halobacteria. In a study of Halobacterium salinarum, Haloarcula marismortui and Halorubrum sodomense, using different analytical techniques to monitor the production of different carotenoids as a function of the presence of nicotine, we showed that the formation of α-bacterioruberin was inhibited in all. In Hbt. salinarum, addition of nicotine led to a significant change in the color of the culture due to the accumulation of lycopene, in addition to the formation of bisanhydrobacterioruberin which does not differ in color from α-bacterioruberin. Very little or no lycopene was formed in Har. marismortui and in Hrr. sodomense; instead bisanhydrobacterioruberin was the only major carotenoid found in nicotine-amended cultures. The findings are discussed in the framework of the recently elucidated biochemical pathway for the formation of the different carotenoid pigments encountered in the Halobacteria.},
}
@article {pmid29329319,
year = {2018},
author = {Bader, M and Müller, K and Foerstendorf, H and Schmidt, M and Simmons, K and Swanson, JS and Reed, DT and Stumpf, T and Cherkouk, A},
title = {Comparative analysis of uranium bioassociation with halophilic bacteria and archaea.},
journal = {PloS one},
volume = {13},
number = {1},
pages = {e0190953},
pmid = {29329319},
issn = {1932-6203},
mesh = {Bacteria/classification/growth &amp; development/*metabolism ; Halobacterium/classification/growth &amp; development/*metabolism ; Microscopy, Electron, Scanning ; Phylogeny ; Radioactive Waste ; Spectrometry, X-Ray Emission ; Spectroscopy, Fourier Transform Infrared ; Uranium/*metabolism ; },
abstract = {Rock salt represents a potential host rock formation for the final disposal of radioactive waste. The interactions between indigenous microorganisms and radionuclides, e.g. uranium, need to be investigated to better predict the influence of microorganisms on the safety assessment of the repository. Hence, the association process of uranium with two microorganisms isolated from rock salt was comparatively studied. Brachybacterium sp. G1, which was isolated from the German salt dome Gorleben, and Halobacterium noricense DSM15987T, were selected as examples of a moderately halophilic bacterium and an extremely halophilic archaeon, respectively. The microorganisms exhibited completely different association behaviors with uranium. While a pure biosorption process took place with Brachybacterium sp. G1 cells, a multistage association process occurred with the archaeon. In addition to batch experiments, in situ attenuated total reflection Fourier-transform infrared spectroscopy was applied to characterize the U(VI) interaction process. Biosorption was identified as the dominating process for Brachybacterium sp. G1 with this method. Carboxylic functionalities are the dominant interacting groups for the bacterium, whereas phosphoryl groups are also involved in U(VI) association by the archaeon H. noricense.},
}
@article {pmid29322393,
year = {2018},
author = {Srithep, P and Pornkulwat, P and Limpiyakorn, T},
title = {Contribution of ammonia-oxidizing archaea and ammonia-oxidizing bacteria to ammonia oxidation in two nitrifying reactors.},
journal = {Environmental science and pollution research international},
volume = {25},
number = {9},
pages = {8676-8687},
pmid = {29322393},
issn = {1614-7499},
support = {RSA5780036//Thailand Research Fund (TH)/ ; },
mesh = {Ammonia/*analysis ; Archaea/genetics/*isolation &amp; purification ; Autotrophic Processes ; Betaproteobacteria/genetics/*isolation &amp; purification ; Bioreactors/*microbiology ; Oxidation-Reduction ; Phylogeny ; Sewage/microbiology ; Water Pollutants, Chemical/*analysis ; Water Purification/*methods ; },
abstract = {In this study, two laboratory nitrifying reactors (NRI and NRII), which were seeded by sludge from different sources and operated under different operating conditions, were found to possess distinct dominant ammonia-oxidizing microorganisms. Ammonia-oxidizing archaeal (AOA) amoA genes outnumbered ammonia-oxidizing bacterial (AOB) amoA genes in reactor NRI, while only AOB amoA genes were detectable in reactor NRII. The AOA amoA gene sequences retrieved from NRI were characterized within the Nitrososphaera sister cluster of the group 1.1b Thaumarchaeota. Two inhibitors for ammonia oxidation, allylthiourea (ATU) and 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (PTIO), were applied individually and as a mixture to observe the ammonia-oxidizing activity of both microorganisms in the reactors' sludge. The results indicated that AOA and AOB jointly oxidized ammonia in NRI, while AOB played the main role in ammonia oxidation in NRII. DNA-stable isotope probing with labeled 13C-HCO3- was performed on NRI sludge. Incorporation of 13C into AOA and AOB implied that both microorganisms may perform autotrophy during ammonia oxidation. Taken together, the results from this study provide direct evidence demonstrating the contribution of AOA and AOB to ammonia oxidation in the nitrifying reactors.},
}
@article {pmid29268981,
year = {2018},
author = {Kelman, LM and Kelman, Z},
title = {Do Archaea Need an Origin of Replication?.},
journal = {Trends in microbiology},
volume = {26},
number = {3},
pages = {172-174},
doi = {10.1016/j.tim.2017.12.001},
pmid = {29268981},
issn = {1878-4380},
mesh = {Archaea/*genetics/growth &amp; development/metabolism ; Archaeal Proteins/genetics/metabolism ; Chromosomes, Archaeal/genetics ; DNA Replication/genetics/physiology ; DNA, Archaeal/genetics ; Genes, Archaeal/*genetics ; Microbial Viability/genetics ; Replication Origin/*genetics/*physiology ; },
abstract = {Chromosomal DNA replication starts at a specific region called an origin of replication. Until recently, all organisms were thought to require origins to replicate their chromosomes. It was recently discovered that some archaeal species do not utilize origins of replication under laboratory growth conditions.},
}
@article {pmid29235710,
year = {2018},
author = {Xie, W and Luo, H and Murugapiran, SK and Dodsworth, JA and Chen, S and Sun, Y and Hedlund, BP and Wang, P and Fang, H and Deng, M and Zhang, CL},
title = {Localized high abundance of Marine Group II archaea in the subtropical Pearl River Estuary: implications for their niche adaptation.},
journal = {Environmental microbiology},
volume = {20},
number = {2},
pages = {734-754},
doi = {10.1111/1462-2920.14004},
pmid = {29235710},
issn = {1462-2920},
mesh = {Adaptation, Physiological/*physiology ; Archaea/classification/*genetics/isolation &amp; purification/*metabolism ; China ; Ecology ; Estuaries ; Metagenome/genetics ; Phylogeny ; Plankton/*growth &amp; development ; RNA, Ribosomal, 16S/genetics ; Rivers/*microbiology ; Salinity ; Seawater/microbiology ; },
abstract = {Marine Group II archaea are widely distributed in global oceans and dominate the total archaeal community within the upper euphotic zone of temperate waters. However, factors controlling the distribution of MGII are poorly delineated and the physiology and ecological functions of these still-uncultured organisms remain elusive. In this study, we investigated the planktonic MGII associated with particles and in free-living forms in the Pearl River Estuary (PRE) over a 10-month period. We detected high abundance of particle-associated MGII in PRE (up to ∼108 16S rRNA gene copies/l), which was around 10-fold higher than the free-living MGII in the same region, and an order of magnitude higher than previously reported in other marine environments. 10‰ salinity appeared to be a threshold value for these MGII because MGII abundance decreased sharply below it. Above 10‰ salinity, the abundance of MGII on the particles was positively correlated with phototrophs and MGII in the surface water was negatively correlated with irradiance. However, the abundances of those free-living MGII showed positive correlations with salinity and temperature, suggesting the different physiological characteristics between particle-attached and free-living MGIIs. A nearly completely assembled metagenome, MGIIa_P, was recovered using metagenome binning methods. Compared with the other two MGII genomes from surface ocean, MGIIa_P contained higher proportions of glycoside hydrolases, indicating the ability of MGIIa_P to hydrolyse glycosidic bonds in complex sugars in PRE. MGIIa_P is the first assembled MGII metagenome containing a catalase gene, which might be involved in scavenging reactive oxygen species generated by the abundant phototrophs in the eutrophic PRE. Our study presented the widespread and high abundance of MGII in the water columns of PRE, and characterized the determinant abiotic factors affecting their distribution. Their association with heterotrophs, preference for particles and resourceful metabolic traits indicate MGII might play a significant role in metabolising organic matters in the PRE and other temperate estuarine systems.},
}
@article {pmid29222443,
year = {2018},
author = {Chen, LX and Méndez-García, C and Dombrowski, N and Servín-Garcidueñas, LE and Eloe-Fadrosh, EA and Fang, BZ and Luo, ZH and Tan, S and Zhi, XY and Hua, ZS and Martinez-Romero, E and Woyke, T and Huang, LN and Sánchez, J and Peláez, AI and Ferrer, M and Baker, BJ and Shu, WS},
title = {Metabolic versatility of small archaea Micrarchaeota and Parvarchaeota.},
journal = {The ISME journal},
volume = {12},
number = {3},
pages = {756-775},
pmid = {29222443},
issn = {1751-7370},
mesh = {Amino Acids/metabolism ; Archaea/classification/genetics/isolation &amp; purification/*metabolism ; Biodiversity ; Biological Evolution ; Carbon/metabolism ; Fresh Water/microbiology ; Genome, Archaeal ; Genomics ; Hot Springs/microbiology ; Iron/metabolism ; Nitrogen/metabolism ; Nitrogen Cycle ; Phylogeny ; RNA, Ribosomal, 16S/genetics ; },
abstract = {Small acidophilic archaea belonging to Micrarchaeota and Parvarchaeota phyla are known to physically interact with some Thermoplasmatales members in nature. However, due to a lack of cultivation and limited genomes on hand, their biodiversity, metabolisms, and physiologies remain largely unresolved. Here, we obtained 39 genomes from acid mine drainage (AMD) and hot spring environments around the world. 16S rRNA gene based analyses revealed that Parvarchaeota were only detected in AMD and hot spring habitats, while Micrarchaeota were also detected in others including soil, peat, hypersaline mat, and freshwater, suggesting a considerable higher diversity and broader than expected habitat distribution for this phylum. Despite their small genomes (0.64-1.08 Mb), these archaea may contribute to carbon and nitrogen cycling by degrading multiple saccharides and proteins, and produce ATP via aerobic respiration and fermentation. Additionally, we identified several syntenic genes with homology to those involved in iron oxidation in six Parvarchaeota genomes, suggesting their potential role in iron cycling. However, both phyla lack biosynthetic pathways for amino acids and nucleotides, suggesting that they likely scavenge these biomolecules from the environment and/or other community members. Moreover, low-oxygen enrichments in laboratory confirmed our speculation that both phyla are microaerobic/anaerobic, based on several specific genes identified in them. Furthermore, phylogenetic analyses provide insights into the close evolutionary history of energy related functionalities between both phyla with Thermoplasmatales. These results expand our understanding of these elusive archaea by revealing their involvement in carbon, nitrogen, and iron cycling, and suggest their potential interactions with Thermoplasmatales on genomic scale.},
}
@article {pmid29218041,
year = {2017},
author = {Ito, M and Morino, M and Krulwich, TA},
title = {Mrp Antiporters Have Important Roles in Diverse Bacteria and Archaea.},
journal = {Frontiers in microbiology},
volume = {8},
number = {},
pages = {2325},
pmid = {29218041},
issn = {1664-302X},
support = {R01 GM028454/GM/NIGMS NIH HHS/United States ; },
abstract = {Mrp (Multiple resistance and pH) antiporter was identified as a gene complementing an alkaline-sensitive mutant strain of alkaliphilic Bacillus halodurans C-125 in 1990. At that time, there was no example of a multi-subunit type Na+/H+ antiporter comprising six or seven hydrophobic proteins, and it was newly designated as the monovalent cation: proton antiporter-3 (CPA3) family in the classification of transporters. The Mrp antiporter is broadly distributed among bacteria and archaea, not only in alkaliphiles. Generally, all Mrp subunits, mrpA-G, are required for enzymatic activity. Two exceptions are Mrp from the archaea Methanosarcina acetivorans and the eubacteria Natranaerobius thermophilus, which are reported to sustain Na+/H+ antiport activity with the MrpA subunit alone. Two large subunits of the Mrp antiporter, MrpA and MrpD, are homologous to membrane-embedded subunits of the respiratory chain complex I, NuoL, NuoM, and NuoN, and the small subunit MrpC has homology with NuoK. The functions of the Mrp antiporter include sodium tolerance and pH homeostasis in an alkaline environment, nitrogen fixation in Schizolobium meliloti, bile salt tolerance in Bacillus subtilis and Vibrio cholerae, arsenic oxidation in Agrobacterium tumefaciens, pathogenesis in Pseudomonas aeruginosa and Staphylococcus aureus, and the conversion of energy involved in metabolism and hydrogen production in archaea. In addition, some Mrp antiporters transport K+ and Ca2+ instead of Na+, depending on the environmental conditions. Recently, the molecular structure of the respiratory chain complex I has been elucidated by others, and details of the mechanism by which it transports protons are being clarified. Based on this, several hypotheses concerning the substrate transport mechanism in the Mrp antiporter have been proposed. The MrpA and MrpD subunits, which are homologous to the proton transport subunit of complex I, are involved in the transport of protons and their coupling cations. Herein, we outline other recent findings on the Mrp antiporter.},
}
@article {pmid29208997,
year = {2017},
author = {Miot, J and Bernard, S and Bourreau, M and Guyot, F and Kish, A},
title = {Experimental maturation of Archaea encrusted by Fe-phosphates.},
journal = {Scientific reports},
volume = {7},
number = {1},
pages = {16984},
pmid = {29208997},
issn = {2045-2322},
mesh = {*Ferrous Compounds/chemistry ; *Fossils ; Hydrogen-Ion Concentration ; Microscopy, Electron, Transmission ; Minerals/chemistry ; *Phosphates/chemistry ; Sulfolobus acidocaldarius/growth &amp; development/*physiology/ultrastructure ; Temperature ; X-Ray Absorption Spectroscopy ; X-Ray Diffraction ; },
abstract = {Burial is generally detrimental to the preservation of biological signals. It has often been assumed that (bio)mineral-encrusted microorganisms are more resistant to burial-induced degradation than non-encrusted ones over geological timescales. For the present study, we submitted Sulfolobus acidocaldarius experimentally encrusted by amorphous Fe phosphates to constrained temperature conditions (150 °C) under pressure for 1 to 5 days, thereby simulating burial-induced processes. We document the molecular and mineralogical evolution of these assemblages down to the sub-micrometer scale using X-ray diffraction, scanning and transmission electron microscopies and synchrotron-based X-ray absorption near edge structure spectroscopy at the carbon K-edge. The present results demonstrate that the presence of Fe-phosphates enhances the chemical degradation of microbial organic matter. While Fe-phosphates remained amorphous in abiotic controls, crystalline lipscombite (FeIIxFeIII3-x(PO4)2(OH)3-x) entrapping organic matter formed in the presence of S. acidocaldarius cells. Lipscombite textures (framboidal vs. bipyramidal) appeared only controlled by the initial level of encrustation of the cells, suggesting that the initial organic matter to mineral ratio influences the competition between nucleation and crystal growth. Altogether these results highlight the important interplay between minerals and organic matter during fossilization, which should be taken into account when interpreting the fossil record.},
}
@article {pmid29208747,
year = {2017},
author = {Makarova, KS and Galperin, MY and Koonin, EV},
title = {Proposed Role for KaiC-Like ATPases as Major Signal Transduction Hubs in Archaea.},
journal = {mBio},
volume = {8},
number = {6},
pages = {},
pmid = {29208747},
issn = {2150-7511},
mesh = {Adenosine Triphosphatases/*genetics ; Archaea/classification/*genetics/metabolism ; Archaeal Proteins/genetics/metabolism ; Bacterial Proteins/genetics ; Circadian Clocks ; Circadian Rhythm Signaling Peptides and Proteins/*genetics ; Cluster Analysis ; Cyanobacteria/genetics ; Databases, Genetic ; Gene Expression Regulation, Archaeal ; Genomics ; Membrane Transport Proteins ; Models, Genetic ; Multigene Family ; Protein Domains ; *Signal Transduction ; },
abstract = {All organisms must adapt to ever-changing environmental conditions and accordingly have evolved diverse signal transduction systems. In bacteria, the most abundant networks are built around the two-component signal transduction systems that include histidine kinases and receiver domains. In contrast, eukaryotic signal transduction is dominated by serine/threonine/tyrosine protein kinases. Both of these systems are also found in archaea, but they are not as common and diversified as their bacterial and eukaryotic counterparts, suggesting the possibility that archaea have evolved other, still uncharacterized signal transduction networks. Here we propose a role for KaiC family ATPases, known to be key components of the circadian clock in cyanobacteria, in archaeal signal transduction. The KaiC family is notably expanded in most archaeal genomes, and although most of these ATPases remain poorly characterized, members of the KaiC family have been shown to control archaellum assembly and have been found to be a stable component of the gas vesicle system in Halobacteria Computational analyses described here suggest that KaiC-like ATPases and their homologues with inactivated ATPase domains are involved in many other archaeal signal transduction pathways and comprise major hubs of complex regulatory networks. We predict numerous input and output domains that are linked to KaiC-like proteins, including putative homologues of eukaryotic DEATH domains that could function as adapters in archaeal signaling networks. We further address the relationships of the archaeal family of KaiC homologues to the bona fide KaiC of cyanobacteria and implications for the existence of a KaiC-based circadian clock apparatus in archaea.IMPORTANCE Little is currently known about signal transduction pathways in Archaea Recent studies indicate that KaiC-like ATPases, known as key components of the circadian clock apparatus in cyanobacteria, are involved in the regulation of archaellum assembly and, likely, type IV pili and the gas vesicle system in Archaea We performed comprehensive comparative genomic analyses of the KaiC family. A vast protein interaction network was revealed, with KaiC family proteins as hubs for numerous input and output components, many of which are shared with two-component signal transduction systems. Putative KaiC-based signal transduction systems are predicted to regulate the activities of membrane-associated complexes and individual proteins, such as signal recognition particle and membrane transporters, and also could be important for oxidative stress response regulation. KaiC-centered signal transduction networks are predicted to play major roles in archaeal physiology, and this work is expected to stimulate their experimental characterization.},
}
@article {pmid29198957,
year = {2018},
author = {Kazlauskas, D and Sezonov, G and Charpin, N and Venclovas, Č and Forterre, P and Krupovic, M},
title = {Novel Families of Archaeo-Eukaryotic Primases Associated with Mobile Genetic Elements of Bacteria and Archaea.},
journal = {Journal of molecular biology},
volume = {430},
number = {5},
pages = {737-750},
pmid = {29198957},
issn = {1089-8638},
support = {340440//European Research Council/International ; },
mesh = {Amino Acid Sequence ; Archaea/*enzymology/*genetics ; Bacteria/enzymology/*genetics ; Catalytic Domain ; DNA Helicases/metabolism ; DNA Primase/classification/*metabolism ; DNA Replication ; Eukaryota/*enzymology/*genetics ; Evolution, Molecular ; Interspersed Repetitive Sequences ; Models, Molecular ; Protein Conformation ; Protein Domains ; Sequence Alignment ; Thermococcus/genetics ; },
abstract = {Cellular organisms in different domains of life employ structurally unrelated, non-homologous DNA primases for synthesis of a primer for DNA replication. Archaea and eukaryotes encode enzymes of the archaeo-eukaryotic primase (AEP) superfamily, whereas bacteria uniformly use primases of the DnaG family. However, AEP genes are widespread in bacterial genomes raising questions regarding their provenance and function. Here, using an archaeal primase-polymerase PolpTN2 encoded by pTN2 plasmid as a seed for sequence similarity searches, we recovered over 800 AEP homologs from bacteria belonging to 12 highly diverse phyla. These sequences formed a supergroup, PrimPol-PV1, and could be classified into five novel AEP families which are characterized by a conserved motif containing an arginine residue likely to be involved in nucleotide binding. Functional assays confirm the essentiality of this motif for catalytic activity of the PolpTN2 primase-polymerase. Further analyses showed that bacterial AEPs display a range of domain organizations and uncovered several candidates for novel families of helicases. Furthermore, sequence and structure comparisons suggest that PriCT-1 and PriCT-2 domains frequently fused to the AEP domains are related to each other as well as to the non-catalytic, large subunit of archaeal and eukaryotic primases, and to the recently discovered PriX subunit of archaeal primases. Finally, genomic neighborhood analysis indicates that the identified AEPs encoded in bacterial genomes are nearly exclusively associated with highly diverse integrated mobile genetic elements, including integrative conjugative plasmids and prophages.},
}
@article {pmid29194812,
year = {2018},
author = {Chaudhury, P and Quax, TEF and Albers, SV},
title = {Versatile cell surface structures of archaea.},
journal = {Molecular microbiology},
volume = {107},
number = {3},
pages = {298-311},
doi = {10.1111/mmi.13889},
pmid = {29194812},
issn = {1365-2958},
mesh = {Archaea/metabolism/*physiology ; Bacterial Adhesion/physiology ; Biofilms ; Fimbriae, Bacterial/*metabolism/physiology ; Membrane Proteins/metabolism ; Pili, Sex/physiology ; },
abstract = {Archaea are ubiquitously present in nature and colonize environments with broadly varying growth conditions. Several surface appendages support their colonization of new habitats. A hallmark of archaea seems to be the high abundance of type IV pili (T4P). However, some unique non T4 filaments are present in a number of archaeal species. Archaeal surface structures can mediate different processes such as cellular surface adhesion, DNA exchange, motility and biofilm formation and represent an initial attachment site for infecting viruses. In addition to the functionally characterized archaeal T4P, archaeal genomes encode a large number of T4P components that might form yet undiscovered surface structures with novel functions. In this review, we summarize recent advancement in structural and functional characterizations of known archaeal surface structures and highlight the diverse processes in which they play a role.},
}
@article {pmid29184545,
year = {2017},
author = {Yang, W and Wang, Y and Tago, K and Tokuda, S and Hayatsu, M},
title = {Comparison of the Effects of Phenylhydrazine Hydrochloride and Dicyandiamide on Ammonia-Oxidizing Bacteria and Archaea in Andosols.},
journal = {Frontiers in microbiology},
volume = {8},
number = {},
pages = {2226},
pmid = {29184545},
issn = {1664-302X},
abstract = {Dicyandiamide, a routinely used commercial nitrification inhibitor (NI), inhibits ammonia oxidation catalyzed by ammonia monooxygenase (AMO). Phenylhydrazine hydrochloride has shown considerable potential for the development of next-generation NIs targeting hydroxylamine dehydrogenase (HAO). The effects of the AMO inhibitor and the HAO inhibitor on ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) present in agricultural soils have not been compared thus far. In the present study, the effects of the two inhibitors on soil nitrification and the abundance of AOA and AOB as well as their community structure were investigated in a soil microcosm using quantitative polymerase chain reaction and pyrosequencing. The net nitrification rates and the growth of AOA and AOB in this soil microcosm were inhibited by both NIs. Both NIs had limited effect on the community structure of AOB and no effect on that of AOA in this soil microcosm. The effects of phenylhydrazine hydrochloride were similar to those of dicyandiamide. These results indicated that organohydrazine-based NIs have potential for the development of next-generation NIs targeting HAO in the future.},
}
@article {pmid29178818,
year = {2017},
author = {Martinez-Pastor, M and Tonner, PD and Darnell, CL and Schmid, AK},
title = {Transcriptional Regulation in Archaea: From Individual Genes to Global Regulatory Networks.},
journal = {Annual review of genetics},
volume = {51},
number = {},
pages = {143-170},
doi = {10.1146/annurev-genet-120116-023413},
pmid = {29178818},
issn = {1545-2948},
mesh = {Adaptation, Biological/genetics ; Archaea/*genetics/metabolism ; Archaeal Proteins/*genetics/metabolism ; Chromosome Mapping ; *Gene Expression Regulation, Archaeal ; *Gene Regulatory Networks ; Gene-Environment Interaction ; *Genome, Archaeal ; Metabolic Networks and Pathways/genetics ; Stress, Physiological/genetics ; Systems Biology/methods ; Transcription Factors/*genetics/metabolism ; *Transcription, Genetic ; },
abstract = {Archaea are major contributors to biogeochemical cycles, possess unique metabolic capabilities, and resist extreme stress. To regulate the expression of genes encoding these unique programs, archaeal cells use gene regulatory networks (GRNs) composed of transcription factor proteins and their target genes. Recent developments in genetics, genomics, and computational methods used with archaeal model organisms have enabled the mapping and prediction of global GRN structures. Experimental tests of these predictions have revealed the dynamical function of GRNs in response to environmental variation. Here, we review recent progress made in this area, from investigating the mechanisms of transcriptional regulation of individual genes to small-scale subnetworks and genome-wide global networks. At each level, archaeal GRNs consist of a hybrid of bacterial, eukaryotic, and uniquely archaeal mechanisms. We discuss this theme from the perspective of the role of individual transcription factors in genome-wide regulation, how these proteins interact to compile GRN topological structures, and how these topologies lead to emergent, high-level GRN functions. We conclude by discussing how systems biology approaches are a fruitful avenue for addressing remaining challenges, such as discovering gene function and the evolution of GRNs.},
}
@article {pmid29176585,
year = {2018},
author = {Eme, L and Spang, A and Lombard, J and Stairs, CW and Ettema, TJG},
title = {Archaea and the origin of eukaryotes.},
journal = {Nature reviews. Microbiology},
volume = {16},
number = {2},
pages = {120},
pmid = {29176585},
issn = {1740-1534},
abstract = {This corrects the article DOI: 10.1038/nrmicro.2017.133.},
}
@article {pmid29175107,
year = {2018},
author = {Krupovic, M and Cvirkaite-Krupovic, V and Iranzo, J and Prangishvili, D and Koonin, EV},
title = {Viruses of archaea: Structural, functional, environmental and evolutionary genomics.},
journal = {Virus research},
volume = {244},
number = {},
pages = {181-193},
pmid = {29175107},
issn = {1872-7492},
support = {Z01 LM000073-12/NULL/Intramural NIH HHS/United States ; },
mesh = {Aquatic Organisms/virology ; Archaea/*virology ; Archaeal Viruses/classification/*genetics/isolation &amp; purification/ultrastructure ; Evolution, Molecular ; Genetic Variation ; *Genome, Viral ; Interspersed Repetitive Sequences ; Metagenomics/*methods ; Microbial Interactions ; *Phylogeny ; Sequence Analysis, DNA ; Viral Proteins/*genetics ; Virion/genetics/ultrastructure ; },
abstract = {Viruses of archaea represent one of the most enigmatic parts of the virosphere. Most of the characterized archaeal viruses infect extremophilic hosts and display remarkable diversity of virion morphotypes, many of which have never been observed among viruses of bacteria or eukaryotes. The uniqueness of the virion morphologies is matched by the distinctiveness of the genomes of these viruses, with ∼75% of genes encoding unique proteins, refractory to functional annotation based on sequence analyses. In this review, we summarize the state-of-the-art knowledge on various aspects of archaeal virus genomics. First, we outline how structural and functional genomics efforts provided valuable insights into the functions of viral proteins and revealed intricate details of the archaeal virus-host interactions. We then highlight recent metagenomics studies, which provided a glimpse at the diversity of uncultivated viruses associated with the ubiquitous archaea in the oceans, including Thaumarchaeota, Marine Group II Euryarchaeota, and others. These findings, combined with the recent discovery that archaeal viruses mediate a rapid turnover of thaumarchaea in the deep sea ecosystems, illuminate the prominent role of these viruses in the biosphere. Finally, we discuss the origins and evolution of archaeal viruses and emphasize the evolutionary relationships between viruses and non-viral mobile genetic elements. Further exploration of the archaeal virus diversity as well as functional studies on diverse virus-host systems are bound to uncover novel, unexpected facets of the archaeal virome.},
}
@article {pmid29170214,
year = {2017},
author = {Pennisi, E},
title = {Survey of archaea in the body reveals other microbial guests.},
journal = {Science (New York, N.Y.)},
volume = {358},
number = {6366},
pages = {983},
doi = {10.1126/science.358.6366.983},
pmid = {29170214},
issn = {1095-9203},
mesh = {Constipation/microbiology ; Digestion ; *Gastrointestinal Microbiome ; Gastrointestinal Tract/*microbiology ; Humans ; Lung/microbiology ; Methane/*biosynthesis ; Methanobrevibacter/*pathogenicity ; Nose/microbiology ; Skin/microbiology ; },
}
@article {pmid29138298,
year = {2017},
author = {Koskinen, K and Pausan, MR and Perras, AK and Beck, M and Bang, C and Mora, M and Schilhabel, A and Schmitz, R and Moissl-Eichinger, C},
title = {First Insights into the Diverse Human Archaeome: Specific Detection of Archaea in the Gastrointestinal Tract, Lung, and Nose and on Skin.},
journal = {mBio},
volume = {8},
number = {6},
pages = {},
pmid = {29138298},
issn = {2150-7511},
mesh = {Archaea/*classification/genetics/*isolation &amp; purification ; Gastrointestinal Tract/*microbiology ; Humans ; Lung/*microbiology ; Metagenomics/methods ; *Microbiota ; Nose/*microbiology ; Polymerase Chain Reaction/methods ; Skin/*microbiology ; },
abstract = {Human-associated archaea remain understudied in the field of microbiome research, although in particular methanogenic archaea were found to be regular commensals of the human gut, where they represent keystone species in metabolic processes. Knowledge on the abundance and diversity of human-associated archaea is extremely limited, and little is known about their function(s), their overall role in human health, or their association with parts of the human body other than the gastrointestinal tract and oral cavity. Currently, methodological issues impede the full assessment of the human archaeome, as bacteria-targeting protocols are unsuitable for characterization of the full spectrum of Archaea The goal of this study was to establish conservative protocols based on specifically archaea-targeting, PCR-based methods to retrieve first insights into the archaeomes of the human gastrointestinal tract, lung, nose, and skin. Detection of Archaea was highly dependent on primer selection and the sequence processing pipeline used. Our results enabled us to retrieve a novel picture of the human archaeome, as we found for the first time Methanobacterium and Woesearchaeota (DPANN superphylum) to be associated with the human gastrointestinal tract and the human lung, respectively. Similar to bacteria, human-associated archaeal communities were found to group biogeographically, forming (i) the thaumarchaeal skin landscape, (ii) the (methano)euryarchaeal gastrointestinal tract, (iii) a mixed skin-gastrointestinal tract landscape for the nose, and (iv) a woesearchaeal lung landscape. On the basis of the protocols we used, we were able to detect unexpectedly high diversity of archaea associated with different body parts.IMPORTANCE In summary, our study highlights the importance of the primers and data processing pipeline used to study the human archaeome. We were able to establish protocols that revealed the presence of previously undetected Archaea in all of the tissue samples investigated and to detect biogeographic patterns of the human archaeome in the gastrointestinal tract and on the skin and for the first time in the respiratory tract, i.e., the nose and lungs. Our results are a solid basis for further investigation of the human archaeome and, in the long term, discovery of the potential role of archaea in human health and disease.},
}
@article {pmid29138003,
year = {2018},
author = {Stancik, IA and Šestak, MS and Ji, B and Axelson-Fisk, M and Franjevic, D and Jers, C and Domazet-Lošo, T and Mijakovic, I},
title = {Serine/Threonine Protein Kinases from Bacteria, Archaea and Eukarya Share a Common Evolutionary Origin Deeply Rooted in the Tree of Life.},
journal = {Journal of molecular biology},
volume = {430},
number = {1},
pages = {27-32},
doi = {10.1016/j.jmb.2017.11.004},
pmid = {29138003},
issn = {1089-8638},
mesh = {Amino Acid Sequence ; Archaea/*genetics ; Bacteria/*genetics ; Eukaryota/*genetics ; Evolution, Molecular ; Protein-Serine-Threonine Kinases/*genetics ; },
abstract = {The main family of serine/threonine/tyrosine protein kinases present in eukarya was defined and described by Hanks et al. in 1988 (Science, 241, 42-52). It was initially believed that these kinases do not exist in bacteria, but extensive genome sequencing revealed their existence in many bacteria. For historical reasons, the term &quot;eukaryotic-type kinases&quot; propagated in the literature to describe bacterial members of this protein family. Here, we argue that this term should be abandoned as a misnomer, and we provide several lines of evidence to support this claim. Our comprehensive phylostratigraphic analysis suggests that Hanks-type kinases present in eukarya, bacteria and archaea all share a common evolutionary origin in the lineage leading to the last universal common ancestor (LUCA). We found no evidence to suggest substantial horizontal transfer of genes encoding Hanks-type kinases from eukarya to bacteria. Moreover, our systematic structural comparison suggests that bacterial Hanks-type kinases resemble their eukaryal counterparts very closely, while their structures appear to be dissimilar from other kinase families of bacterial origin. This indicates that a convergent evolution scenario, by which bacterial kinases could have evolved a kinase domain similar to that of eukaryal Hanks-type kinases, is not very likely. Overall, our results strongly support a monophyletic origin of all Hanks-type kinases, and we therefore propose that this term should be adopted as a universal name for this protein family.},
}
@article {pmid29123229,
year = {2017},
author = {},
title = {A flourishing field: going back to the roots of the Archaea.},
journal = {Nature reviews. Microbiology},
volume = {15},
number = {12},
pages = {705},
pmid = {29123229},
issn = {1740-1534},
mesh = {Adaptation, Biological/*genetics ; Archaea/classification/*genetics/physiology/virology ; Bacteria/genetics ; *Biodiversity ; Ecology ; Eukaryota/genetics ; Gene Transfer, Horizontal ; *Genetic Speciation ; Genome, Archaeal/*genetics ; },
}
@article {pmid29123225,
year = {2017},
author = {Eme, L and Spang, A and Lombard, J and Stairs, CW and Ettema, TJG},
title = {Archaea and the origin of eukaryotes.},
journal = {Nature reviews. Microbiology},
volume = {15},
number = {12},
pages = {711-723},
pmid = {29123225},
issn = {1740-1534},
mesh = {Archaea/*genetics ; *Biological Evolution ; Eukaryota/*genetics ; Pharmacogenomic Variants ; },
abstract = {Woese and Fox's 1977 paper on the discovery of the Archaea triggered a revolution in the field of evolutionary biology by showing that life was divided into not only prokaryotes and eukaryotes. Rather, they revealed that prokaryotes comprise two distinct types of organisms, the Bacteria and the Archaea. In subsequent years, molecular phylogenetic analyses indicated that eukaryotes and the Archaea represent sister groups in the tree of life. During the genomic era, it became evident that eukaryotic cells possess a mixture of archaeal and bacterial features in addition to eukaryotic-specific features. Although it has been generally accepted for some time that mitochondria descend from endosymbiotic alphaproteobacteria, the precise evolutionary relationship between eukaryotes and archaea has continued to be a subject of debate. In this Review, we outline a brief history of the changing shape of the tree of life and examine how the recent discovery of a myriad of diverse archaeal lineages has changed our understanding of the evolutionary relationships between the three domains of life and the origin of eukaryotes. Furthermore, we revisit central questions regarding the process of eukaryogenesis and discuss what can currently be inferred about the evolutionary transition from the first to the last eukaryotic common ancestor.},
}
@article {pmid29118356,
year = {2017},
author = {Nordgård, ASR and Bergland, WH and Vadstein, O and Mironov, V and Bakke, R and Østgaard, K and Bakke, I},
title = {Anaerobic digestion of pig manure supernatant at high ammonia concentrations characterized by high abundances of Methanosaeta and non-euryarchaeotal archaea.},
journal = {Scientific reports},
volume = {7},
number = {1},
pages = {15077},
pmid = {29118356},
issn = {2045-2322},
mesh = {Ammonia/*metabolism ; Anaerobiosis ; Animals ; Archaea/classification/genetics/*metabolism ; Bioreactors/microbiology ; Genetic Variation ; Manure/*microbiology ; Methane/metabolism ; Methanosarcinaceae/classification/genetics/*metabolism ; Microbial Consortia/genetics ; Phylogeny ; RNA, Ribosomal, 16S/genetics ; Sewage/microbiology ; Swine ; Temperature ; },
abstract = {We examined the effect of ammonium and temperature on methane production in high rate upflow anaerobic sludge bed reactors treating pig manure supernatant. We operated four reactors at two ammonium concentrations ('low' at 1.9, 'high' at 3.7 g L-1, termed LA and HA reactors, respectively) and at variable temperatures over 358 days. Archaeal and bacterial communities were characterized by Illumina sequencing of 16S rRNA amplicons. Ammonium was a major selective factor for bacterial and archaeal community structure. After ~200 days of adaptation to high ammonium levels, acetate and propionate removal and methane production improved substantially in HA reactors. Aceticlastic Methanosaeta was abundant and positively correlated to methane yield in the HA reactors, whereas Methanosarcina was more abundant in LA reactors. Furthermore, a group of monophyletic OTUs that was related to Thaumarchaeota in phylogenetic analysis was highly abundant in the archaeal communities, particularly in the HA reactors. The most abundant bacterial OTU in LA reactors, representing Syntrophomonadaceae, was also positively correlated to methane yield in the HA reactors, indicating its importance in methane production under ammonia stress. In conclusion, efficient methane production, involving aceticlastic methanogenesis by Methanosaeta took place in the reactors at free ammonia concentrations as high as 1 g L-1.},
}
@article {pmid29109713,
year = {2017},
author = {Xia, X and Guo, W and Liu, H},
title = {Basin Scale Variation on the Composition and Diversity of Archaea in the Pacific Ocean.},
journal = {Frontiers in microbiology},
volume = {8},
number = {},
pages = {2057},
pmid = {29109713},
issn = {1664-302X},
abstract = {The Archaea are a widely distributed group of prokaryotes that inhabit and thrive in many different environments. In the sea, they play key roles in various global biogeochemical processes. Here, in order to investigate the vertical profiles of archaeal community across a large geographic distance, the compositions of archaeal communities in seven seawater columns in the Pacific Ocean were investigated using high throughput 454 pyrosequencing of the 16S rRNA gene. The surface archaeal communities showed lower diversity and greater variability than those in the deeper layers. Two of the major archaeal phyla that displayed different depth preferences were Thaumarchaeota and Euryarchaeota. The majority of Thaumarchaeota belonged to Marine Group I (MGI), which had high relative abundance in deep water. In contrast, Euryarchaeota, which mainly consisted of Marine Group II (MGII) and III (MGIII), were dominant in the surface layer. Compared with MGI and MGII, MGIII were less abundant in seawater and generally absent from the surface water of the subarctic Pacific. In addition, niche separation in the MGI, MGII, and MGIII subgroups was also observed. For example, MGI.C and MGII.A (the major subgroups of MGI and MGII, respectively) displayed a strong negative correlation with each other. The highest level of archaeal diversity was found in the core of an oxygen minimum zone (OMZ) located off Costa Rica, which resulted from the co-occurrence of both anaerobic and aerobic archaea. For example, methanotrophic archaea ANME-2, methanogenic archaea and several sediment origin archaea, such as Marine Benthic Group A (MBGA) and Bathyarchaeota, were all detected at relatively high abundance in the OMZ. Together, our findings indicate that vertical heterogeneities along water columns and latitudinal differentiation in the surface waters are ubiquitous features of archaeal communities in the Pacific Ocean, and the OMZ off Costa Rica is an archaeal biodiversity hot-spot.},
}
@article {pmid29107227,
year = {2018},
author = {Wang, L and Li, Y and Niu, L and Zhang, W and Zhang, H and Wang, L and Wang, P},
title = {Response of ammonia oxidizing archaea and bacteria to decabromodiphenyl ether and copper contamination in river sediments.},
journal = {Chemosphere},
volume = {191},
number = {},
pages = {858-867},
doi = {10.1016/j.chemosphere.2017.10.067},
pmid = {29107227},
issn = {1879-1298},
mesh = {Ammonia/*metabolism ; Archaea/*metabolism ; Bacteria/*metabolism ; Copper/*metabolism ; Environmental Pollutants/analysis/*metabolism ; Geologic Sediments/*chemistry ; Halogenated Diphenyl Ethers/*analysis ; Metals, Heavy/metabolism ; Nitrogen Cycle ; Oxidation-Reduction ; Oxidoreductases/metabolism ; Rivers/*microbiology ; },
abstract = {Ammonia oxidation plays a fundamental role in river nitrogen cycling ecosystems, which is normally governed by both ammonia oxidizing archaea (AOA) and ammonia oxidizing bacteria (AOB). Co-contamination of typical emerging pollutant Polybrominated diphenyl ethers (PBDEs) and heavy metal on AOA and AOB communities in river sediments remains unknown. In this study, multiple analytical tools, including high-throughput pyrosequencing and real-time quantitative PCR (qPCR), were used to reveal the ammonia monooxygenase (AMO) activity, subunit alpha (amoA) gene abundance, and community structures of AOA and AOB in river sediments. It was found that the inhibition of AMO activities was increased with the increase of decabromodiphenyl ether (BDE 209, 1-100 mg kg-1) and copper (Cu, 50-500 mg kg-1) concentrations. Moreover, the synergic effects of BDE 209 and Cu resulted in a higher AMO activity reduction than the individual pollutant BDE 209. The AOA amoA copy number declined by 75.9% and 83.2% and AOB amoA gene abundance declined 82.8% and 90.0% at 20 and 100 mg kg-1 BDE 209 with a 100 mg kg-1 Cu co-contamination, respectively. The pyrosequencing results showed that both AOB and AOA community structures were altered, with a higher change of AOB than that of AOA. The results demonstrated that the AOB microbial community may be better adapted to BDE 209 and Cu pollution, while AOA might possess a greater capacity for stress resistance. Our study provides a better understanding of the ecotoxicological effects of heavy metal and micropollutant combined exposure on AOA and AOB in river sediments.},
}
@article {pmid29098760,
year = {2017},
author = {Herbold, CW and Lehtovirta-Morley, LE and Jung, MY and Jehmlich, N and Hausmann, B and Han, P and Loy, A and Pester, M and Sayavedra-Soto, LA and Rhee, SK and Prosser, JI and Nicol, GW and Wagner, M and Gubry-Rangin, C},
title = {Ammonia-oxidising archaea living at low pH: Insights from comparative genomics.},
journal = {Environmental microbiology},
volume = {19},
number = {12},
pages = {4939-4952},
pmid = {29098760},
issn = {1462-2920},
support = {294343//European Research Council/International ; },
mesh = {Ammonia/*metabolism ; Base Sequence ; Biological Evolution ; DNA, Archaeal/genetics ; Euryarchaeota/*genetics/*metabolism ; Gene Transfer, Horizontal ; Genome, Archaeal/*genetics ; Genomics ; Nitrification/*physiology ; Oxidation-Reduction ; Phylogeny ; Proteomics ; Sequence Analysis, DNA ; Soil/chemistry ; Soil Microbiology ; },
abstract = {Obligate acidophilic members of the thaumarchaeotal genus Candidatus Nitrosotalea play an important role in nitrification in acidic soils, but their evolutionary and physiological adaptations to acidic environments are still poorly understood, with only a single member of this genus (Ca. N. devanaterra) having its genome sequenced. In this study, we sequenced the genomes of two additional cultured Ca. Nitrosotalea strains, extracted an almost complete Ca. Nitrosotalea metagenome-assembled genome from an acidic fen, and performed comparative genomics of the four Ca. Nitrosotalea genomes with 19 other archaeal ammonia oxidiser genomes. Average nucleotide and amino acid identities revealed that the four Ca. Nitrosotalea strains represent separate species within the genus. The four Ca. Nitrosotalea genomes contained a core set of 103 orthologous gene families absent from all other ammonia-oxidizing archaea and, for most of these gene families, expression could be demonstrated in laboratory culture or the environment via proteomic or metatranscriptomic analyses respectively. Phylogenetic analyses indicated that four of these core gene families were acquired by the Ca. Nitrosotalea common ancestor via horizontal gene transfer from acidophilic representatives of Euryarchaeota. We hypothesize that gene exchange with these acidophiles contributed to the competitive success of the Ca. Nitrosotalea lineage in acidic environments.},
}
@article {pmid29084543,
year = {2017},
author = {Lambrecht, J and Cichocki, N and Hübschmann, T and Koch, C and Harms, H and Müller, S},
title = {Flow cytometric quantification, sorting and sequencing of methanogenic archaea based on F420 autofluorescence.},
journal = {Microbial cell factories},
volume = {16},
number = {1},
pages = {180},
pmid = {29084543},
issn = {1475-2859},
mesh = {Archaea/cytology/genetics/*metabolism ; Archaeal Proteins/genetics/metabolism ; Biofuels ; Biomass ; Flow Cytometry ; Methane/*metabolism ; Microscopy, Fluorescence ; Organic Chemicals/chemistry ; RNA, Ribosomal, 16S/chemistry/isolation &amp; purification/metabolism ; Sequence Analysis, DNA ; },
abstract = {BACKGROUND: The widely established production of CH4 from renewable biomass in industrial scale anaerobic reactors may play a major role in the future energy supply. It relies on methanogenic archaea as key organisms which represent the bottleneck in the process. The quantitative analysis of these organisms can help to maximize process performance, uncover disturbances before failure, and may ultimately lead to community-based process control schemes. Existing qPCR and fluorescence microscopy-based methods are very attractive but can be cost-intensive and laborious.<br><br>RESULTS: In this study we present an autofluorescence-based, flow cytometric method for the fast low-cost quantification of methanogenic archaea in complex microbial communities and crude substrates. The method was applied to a methanogenic enrichment culture (MEC) and digester samples (DS). The methanogenic archaea were quantified using the distinct fluorescence of their cofactor F420 in a range from 3.7 × 108 (± 3.3 × 106) cells mL-1 and 1.8 x 109 (± 1.1 × 108) cells mL-1. We evaluated different fixation methods and tested the sample stability. Stable abundance and fluorescence intensity were recorded up to 26 days during aerobic storage in PBS at 6 °C. The discrimination of the whole microbial community from the ubiquitous particle noise was facilitated by SYBR Green I staining and enabled calculation of relative abundances of methanogenic archaea of up to 9.64 ± 0.23% in the MEC and up to 4.43 ± 0.74% in the DS. The metaprofiling of the mcrA gene reinforced the results.<br><br>CONCLUSIONS: The presented method allows for fast and reliable quantification of methanogenic archaea in microbial communities under authentic digester conditions and can thus be useful for process monitoring and control in biogas digesters.},
}
@article {pmid29083035,
year = {2018},
author = {Laskar, F and Das Purkayastha, S and Sen, A and Bhattacharya, MK and Misra, BB},
title = {Diversity of methanogenic archaea in freshwater sediments of lacustrine ecosystems.},
journal = {Journal of basic microbiology},
volume = {58},
number = {2},
pages = {101-119},
doi = {10.1002/jobm.201700341},
pmid = {29083035},
issn = {1521-4028},
mesh = {Archaea/*classification/genetics/growth &amp; development/*metabolism ; *Biodiversity ; DNA, Archaeal/chemistry/genetics ; DNA, Ribosomal/chemistry/genetics ; Fresh Water/*microbiology ; Geologic Sediments/microbiology ; Lakes/microbiology ; Metagenomics/*methods ; Methane/*metabolism ; Microbiological Techniques/*methods ; Oxidoreductases/genetics ; Phylogeny ; RNA, Ribosomal, 16S/genetics ; Sequence Analysis, DNA ; },
abstract = {About half of the global methane (CH4) emission is contributed by the methanogenic archaeal communities leading to a significant increase in global warming. This unprecedented situation has increased the ever growing necessity of evaluating the control measures for limiting CH4 emission to the atmosphere. Unfortunately, research endeavors on the diversity and functional interactions of methanogens are not extensive till date. We anticipate that the study of the diversity of methanogenic community is paramount for understanding the metabolic processes in freshwater lake ecosystems. Although there are several disadvantages of conventional culture-based methods for determining the diversity of methanogenic archaeal communities, in order to understand their ecological roles in natural environments it is required to culture the microbes. Recently different molecular techniques have been developed for determining the structure of methanogenic archaeal communities thriving in freshwater lake ecosystem. The two gene based cloning techniques required for this purpose are 16S rRNA and methyl coenzyme M reductase (mcrA) in addition to the recently developed metagenomics approaches and high throughput next generation sequencing efforts. This review discusses the various methods of culture-dependent and -independent measures of determining the diversity of methanogen communities in lake sediments in lieu of the different molecular approaches and inter-relationships of diversity of methanogenic archaea.},
}
@article {pmid29080506,
year = {2018},
author = {Chaari, M and Theochari, I and Papadimitriou, V and Xenakis, A and Ammar, E},
title = {Encapsulation of carotenoids extracted from halophilic Archaea in oil-in-water (O/W) micro- and nano-emulsions.},
journal = {Colloids and surfaces. B, Biointerfaces},
volume = {161},
number = {},
pages = {219-227},
doi = {10.1016/j.colsurfb.2017.10.042},
pmid = {29080506},
issn = {1873-4367},
mesh = {Archaea/*chemistry ; Carotenoids/*chemistry ; Cyclohexenes/chemistry ; Drug Delivery Systems/methods ; Electron Spin Resonance Spectroscopy ; Emulsions/*chemistry ; Glycerol/chemistry ; Limonene ; Nanostructures/*chemistry ; Octoxynol/chemistry ; Oils/*chemistry ; Polysorbates/chemistry ; Solubility ; Surface-Active Agents/chemistry ; Terpenes/chemistry ; Thermodynamics ; Water/*chemistry ; },
abstract = {Carotenoids extracted from halophilc Archaea have potential health benefits. Their poor water-solubility and low bioavailability is a challenge to their incorporation into foods. The aim of this work was the carotenoids encapsulation into two oil-in-water (O/W) dispersions, to increase their use as functional food applications. A nanoemulsion produced by high pressure homogenization and a spontaneously formed microemulsion were conceived. The limonene was the dispersed oil phase, and mixtures of Triton X-100/Tween-80 (3:1) as emulsifiers and of water/glycerol (2:1) as the continuous aqueous phase. The microemulsion monophasic area was determined through the pseudo-ternary phase diagram. Dynamic Light Scattering was used for the structural characterization of the nano- and micro-emulsions in the presence of the carotenoids. Moreover, the radical scavenging activity of the encapsulated carotenoids was examined by Electron Paramagnetic Resonance spectroscopy. The results confirmed the delivery systems design effectiveness to encapsulate and stabilize the carotenoids for food applications.},
}
@article {pmid29064676,
year = {2017},
author = {White, RH},
title = {Identification and Biosynthesis of 1-Mercaptoethanesulfonic Acid (1-MES), an Analogue of Coenzyme M, Found Widely in the Methanogenic Archaea.},
journal = {Biochemistry},
volume = {56},
number = {46},
pages = {6137-6144},
doi = {10.1021/acs.biochem.7b00971},
pmid = {29064676},
issn = {1520-4995},
mesh = {*Biosynthetic Pathways ; Ethylenes/metabolism ; Mesna/*analogs &amp; derivatives/*metabolism ; Methanococcus/enzymology/growth &amp; development/*metabolism ; Sulfides/metabolism ; Sulfonic Acids/metabolism ; },
abstract = {Here I report on the identification of 1-mercaptoethanesulfonic acid (1-MES), an analogue of 2-mercaptoethanesulfonic acid (coenzyme M, HSCoM). 1-MES and HSCoM were both present in the growth media of eight different methanogens at concentrations ranging from ∼1 to 100 μM. In an effort to determine a chemical origin of 1-MES, several plausible chemical routes were examined each assuming that HSCoM was the precursor. In all examined routes, no 1-MES was formed. However, 1-MES was formed when a solution of vinylsulfonic acid and sulfide were exposed to ultraviolet light. On the basis of these results, I conclude 1-MES is formed enzymatically. This was confirmed by growing a culture of Methanococcus maripaludis S2 in the presence of [1,1',2,2'-2H4]HSCoM and measuring the incorporation of deuterium into 1-MES. 1-MES incorporated three of the four deuteriums from the fed HSCoM. This result is consistent with the abstraction of a C-2 deuterium of the HSCoM, likely by a 5'-dAdoCH2• radical, followed by a radical rearrangement in which the sulfonic acid moves to position C-1, followed by abstraction of a H• likely from 5'-dAdoCH2D. At present, the reason for the production of 1-MES is not clear. This is the first report of the occurrence of 1-MES in Nature.},
}
@article {pmid29038844,
year = {2018},
author = {Hou, J and Cui, HL},
title = {In Vitro Antioxidant, Antihemolytic, and Anticancer Activity of the Carotenoids from Halophilic Archaea.},
journal = {Current microbiology},
volume = {75},
number = {3},
pages = {266-271},
pmid = {29038844},
issn = {1432-0991},
support = {31600002//National Natural Science Foundation of China/ ; 31370054//National Natural Science Foundation of China/ ; },
mesh = {Animals ; Antineoplastic Agents/chemistry/metabolism/*pharmacology ; Antioxidants/chemistry/metabolism/*pharmacology ; Carotenoids/chemistry/metabolism/*pharmacology ; Cell Line ; Cell Survival/drug effects ; Erythrocytes/drug effects ; Factor VIII/chemistry/metabolism/*pharmacology ; Halobacteriaceae/*chemistry/classification/metabolism ; Humans ; Mice ; Sodium Chloride/metabolism ; },
abstract = {Halophilic archaea represent a promising natural source of carotenoids. However, little information is available about the biological effects of carotenoids from halophilic archaea. In this study, the carotenoids produced by seven halophilic archaeal strains Halogeometricum rufum, Halogeometricum limi, Haladaptatus litoreus, Haloplanus vescus, Halopelagius inordinatus, Halogranum rubrum, and Haloferax volcanii were identified by ultraviolet/visible spectroscopy, thin-layer chromatography, and high-performance liquid chromatography-tandem mass spectrometry. The C50 carotenoids bacterioruberin and its derivatives monoanhydrobacterioruberin and bisanhydrobacterioruberin were found to be the predominant carotenoids. The antioxidant capacities of the carotenoids from these strains were significantly higher than β-carotene as determined by 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay. The antihemolytic activities of these carotenoid extracts against H2O2-induced hemolysis in mouse erythrocytes were 3.9-6.3 times higher than β-carotene. A dose-dependent in vitro antiproliferative activity against HepG2 cells was observed for the extract from Hgm. limi, while that from Hpn. vescus exhibited a relatively high activity in a dose-independent manner. These results suggested that halophilic archaea could be considered as an alternative source of natural carotenoids with high antioxidant, antihemolytic, and anticancer activity.},
}
@article {pmid29037137,
year = {2017},
author = {Peng, S and Chu, Z and Lu, J and Li, D and Wang, Y and Yang, S and Zhang, Y},
title = {Heterologous Expression of Chaperones from Hyperthermophilic Archaea Inhibits Aminoglycoside-Induced Protein Misfolding in Escherichia coli.},
journal = {Biochemistry. Biokhimiia},
volume = {82},
number = {10},
pages = {1169-1175},
doi = {10.1134/S0006297917100091},
pmid = {29037137},
issn = {1608-3040},
mesh = {Chaperonin 10/genetics/metabolism ; Chaperonin 60/genetics/*metabolism ; Escherichia coli/*metabolism ; Membrane Potentials/drug effects ; Molecular Chaperones/genetics/metabolism ; Protein Folding/drug effects ; Pyrococcus furiosus/*metabolism ; Recombinant Proteins/biosynthesis/chemistry ; Streptomycin/pharmacology ; },
abstract = {Aminoglycoside antibiotics affect protein translation fidelity and lead to protein aggregation and an increase in intracellular oxidative stress level as well. The overexpression of the chaperonin GroEL/GroES system promotes short-term tolerance to aminoglycosides in Escherichia coli. Here, we demonstrated that the coexpression of prefoldin or Hsp60 originating from the hyperthermophilic archaeon Pyrococcus furiosus in E. coli cells can rescue cell growth and inhibit protein aggregation induced by streptomycin exposure. The results of our study show that hyperthermophilic chaperones endow E. coli with a higher tolerance to streptomycin than the GroEL/GroES system, and that they exert better effects on the reduction of intracellular protein misfolding, indicating that these chaperones have unique features and functions.},
}
@article {pmid29034851,
year = {2017},
author = {Qin, W and Heal, KR and Ramdasi, R and Kobelt, JN and Martens-Habbena, W and Bertagnolli, AD and Amin, SA and Walker, CB and Urakawa, H and Könneke, M and Devol, AH and Moffett, JW and Armbrust, EV and Jensen, GJ and Ingalls, AE and Stahl, DA},
title = {Nitrosopumilus maritimus gen. nov., sp. nov., Nitrosopumilus cobalaminigenes sp. nov., Nitrosopumilus oxyclinae sp. nov., and Nitrosopumilus ureiphilus sp. nov., four marine ammonia-oxidizing archaea of the phylum Thaumarchaeota.},
journal = {International journal of systematic and evolutionary microbiology},
volume = {67},
number = {12},
pages = {5067-5079},
doi = {10.1099/ijsem.0.002416},
pmid = {29034851},
issn = {1466-5034},
mesh = {Ammonia/metabolism ; Archaea/*classification/genetics/isolation &amp; purification ; Base Composition ; DNA, Archaeal/genetics ; Estuaries ; Geologic Sediments/*microbiology ; Glyceryl Ethers/chemistry ; Oxidation-Reduction ; *Phylogeny ; RNA, Ribosomal, 16S/genetics ; Seawater/*microbiology ; Sequence Analysis, DNA ; Washington ; },
abstract = {Four mesophilic, neutrophilic, and aerobic marine ammonia-oxidizing archaea, designated strains SCM1T, HCA1T, HCE1T and PS0T, were isolated from a tropical marine fish tank, dimly lit deep coastal waters, the lower euphotic zone of coastal waters, and near-surface sediment in the Puget Sound estuary, respectively. Cells are straight or slightly curved small rods, 0.15-0.26 µm in diameter and 0.50-1.59 µm in length. Motility was not observed, although strain PS0T possesses genes associated with archaeal flagella and chemotaxis, suggesting it may be motile under some conditions. Cell membranes consist of glycerol dibiphytanyl glycerol tetraether (GDGT) lipids, with crenarchaeol as the major component. Strain SCM1T displays a single surface layer (S-layer) with p6 symmetry, distinct from the p3-S-layer reported for the soil ammonia-oxidizing archaeon Nitrososphaera viennensis EN76T. Respiratory quinones consist of fully saturated and monounsaturated menaquinones with 6 isoprenoid units in the side chain. Cells obtain energy from ammonia oxidation and use carbon dioxide as carbon source; addition of an α-keto acid (α-ketoglutaric acid) was necessary to sustain growth of strains HCA1T, HCE1T, and PS0T. Strain PS0T uses urea as a source of ammonia for energy production and growth. All strains synthesize vitamin B1 (thiamine), B2 (riboflavin), B6 (pyridoxine), and B12 (cobalamin). Optimal growth occurs between 25 and 32 °C, between pH 6.8 and 7.3, and between 25 and 37 ‰ salinity. All strains have a low mol% G+C content of 33.0-34.2. Strains are related by 98 % or greater 16S rRNA gene sequence identity, sharing ~85 % 16S rRNA gene sequence identity with Nitrososphaera viennensis EN76T. All four isolates are well separated by phenotypic and genotypic characteristics and are here assigned to distinct species within the genus Nitrosopumilus gen. nov. Isolates SCM1T (=ATCC TSD-97T =NCIMB 15022T), HCA1T (=ATCC TSD-96T), HCE1T (=ATCC TSD-98T), and PS0T (=ATCC TSD-99T) are type strains of the species Nitrosopumilusmaritimus sp. nov., Nitrosopumilus cobalaminigenes sp. nov., Nitrosopumilus oxyclinae sp. nov., and Nitrosopumilus ureiphilus sp. nov., respectively. In addition, we propose the family Nitrosopumilaceae fam. nov. and the order Nitrosopumilales ord. nov. within the class Nitrososphaeria.},
}
@article {pmid29034077,
year = {2017},
author = {Danovaro, R and Rastelli, E and Corinaldesi, C and Tangherlini, M and Dell'Anno, A},
title = {Marine archaea and archaeal viruses under global change.},
journal = {F1000Research},
volume = {6},
number = {},
pages = {1241},
pmid = {29034077},
issn = {2046-1402},
abstract = {Global change is altering oceanic temperature, salinity, pH, and oxygen concentration, directly and indirectly influencing marine microbial food web structure and function. As microbes represent >90% of the ocean's biomass and are major drivers of biogeochemical cycles, understanding their responses to such changes is fundamental for predicting the consequences of global change on ecosystem functioning. Recent findings indicate that marine archaea and archaeal viruses are active and relevant components of marine microbial assemblages, far more abundant and diverse than was previously thought. Further research is urgently needed to better understand the impacts of global change on virus-archaea dynamics and how archaea and their viruses can interactively influence the ocean's feedbacks on global change.},
}
@article {pmid29033920,
year = {2017},
author = {Jones, DL and Baxter, BK},
title = {DNA Repair and Photoprotection: Mechanisms of Overcoming Environmental Ultraviolet Radiation Exposure in Halophilic Archaea.},
journal = {Frontiers in microbiology},
volume = {8},
number = {},
pages = {1882},
pmid = {29033920},
issn = {1664-302X},
abstract = {Halophilic archaea push the limits of life at several extremes. In particular, they are noted for their biochemical strategies in dealing with osmotic stress, low water activity and cycles of desiccation in their hypersaline environments. Another feature common to their habitats is intense ultraviolet (UV) radiation, which is a challenge that microorganisms must overcome. The consequences of high UV exposure include DNA lesions arising directly from bond rearrangement of adjacent bipyrimidines, or indirectly from oxidative damage, which may ultimately result in mutation and cell death. As such, these microorganisms have evolved a number of strategies to navigate the threat of DNA damage, which we differentiate into two categories: DNA repair and photoprotection. Photoprotection encompasses damage avoidance strategies that serve as a &quot;first line of defense,&quot; and in halophilic archaea include pigmentation by carotenoids, mechanisms of oxidative damage avoidance, polyploidy, and genomic signatures that make DNA less susceptible to photodamage. Photolesions that do arise are addressed by a number of DNA repair mechanisms that halophilic archaea efficiently utilize, which include photoreactivation, nucleotide excision repair, base excision repair, and homologous recombination. This review seeks to place DNA damage, repair, and photoprotection in the context of halophilic archaea and the solar radiation of their hypersaline environments. We also provide new insight into the breadth of strategies and how they may work together to produce remarkable UV-resistance for these microorganisms.},
}
@article {pmid29033916,
year = {2017},
author = {Wang, S and Giller, K and Kreuzer, M and Ulbrich, SE and Braun, U and Schwarm, A},
title = {Contribution of Ruminal Fungi, Archaea, Protozoa, and Bacteria to the Methane Suppression Caused by Oilseed Supplemented Diets.},
journal = {Frontiers in microbiology},
volume = {8},
number = {},
pages = {1864},
pmid = {29033916},
issn = {1664-302X},
abstract = {Dietary lipids can suppress methane emission from ruminants, but effects are variable. Especially the role of bacteria, archaea, fungi and protozoa in mediating the lipid effects is unclear. In the present in vitro study, archaea, fungi and protozoa were selectively inhibited by specific agents. This was fully or almost fully successful for fungi and protozoa as well as archaeal activity as determined by the methyl-coenzyme M reductase alpha subunit gene. Five different microbial treatments were generated: rumen fluid being intact (I), without archaea (-A), without fungi (-F), without protozoa (-P) and with bacteria only (-AFP). A forage-concentrate diet given alone or supplemented with crushed full-fat oilseeds of either safflower (Carthamus tinctorius) or poppy (Papaver somniferum) or camelina (Camelina sativa) at 70 g oil kg-1 diet dry matter was incubated. This added up to 20 treatments with six incubation runs per treatment. All oilseeds suppressed methane emission compared to the non-supplemented control. Compared to the non-supplemented control, -F decreased organic matter (OM) degradation, and short-chain fatty acid concentration was greater with camelina and safflower seeds. Methane suppression per OM digested in -F was greater with camelina seeds (-12 vs.-7% with I, P = 0.06), but smaller with poppy seeds (-4 vs. -8% with I, P = 0.03), and not affected with safflower seeds. With -P, camelina seeds decreased the acetate-to-propionate ratio and enhanced the methane suppression per gram dry matter (18 vs. 10% with I, P = 0.08). Hydrogen recovery was improved with -P in any oilseeds compared to non-supplemented control. No methane emission was detected with the -A and -AFP treatments. In conclusion, concerning methanogenesis, camelina seeds seem to exert effects only on archaea and bacteria. By contrast, with safflower and poppy seeds methane was obviously reduced mainly through the interaction with protozoa or archaea associated with protozoa. This demonstrated that the microbial groups differ in their contribution to the methane suppressing effect dependent on the source of lipid. These findings help to understand how lipid supplementation and microbial groups interact, and thus may assist in making this methane mitigation tool more efficient, but await confirmation in vivo.},
}
@article {pmid29029047,
year = {2017},
author = {Yang, S and Winkel, M and Wagner, D and Liebner, S},
title = {Community structure of rare methanogenic archaea: insight from a single functional group.},
journal = {FEMS microbiology ecology},
volume = {93},
number = {11},
pages = {},
pmid = {29029047},
issn = {1574-6941},
mesh = {Bacteria/*classification/genetics ; *Biodiversity ; DNA Restriction Enzymes/genetics ; Euryarchaeota/*classification/genetics ; Methane/*biosynthesis ; Phylogeny ; RNA, Ribosomal, 16S/genetics ; Soil Microbiology ; },
abstract = {The rare biosphere, the low abundant microbial populations, is suggested to be a conserved way of microbial life. Here we conducted a molecular survey of rare methanogenic archaea in the environment targeting the mcrA gene in order to test if general concepts associated with the structure of the rare bacterial biosphere also apply to single functional groups. Similar to what is known about rare bacterial communities, the contribution of rare methanogens to the alpha diversity is much larger than to Bray-Curtis measures. Moreover, a similar core group of methanogens harbored by the abundant and rare communities suggests similar sources and environmental controls of both groups. Among the communities of different levels of rarity, the conditionally rare methanogenic taxa largely account for the overall community dynamics of the rare biosphere and likely enter the dominant community under favorable environmental conditions. In addition, we observed a positive correlation between the alpha diversity and the production of methane when the rare taxa were taken into account. This supports the concept that increasing microbial biodiversity enhances ecological function. The composition and environmental associations of the rare methanogenic biosphere allow us to conclude that rarity is a conserved way also for single functional groups.},
}
@article {pmid28992595,
year = {2018},
author = {Yilmazel, YD and Zhu, X and Kim, KY and Holmes, DE and Logan, BE},
title = {Electrical current generation in microbial electrolysis cells by hyperthermophilic archaea Ferroglobus placidus and Geoglobus ahangari.},
journal = {Bioelectrochemistry (Amsterdam, Netherlands)},
volume = {119},
number = {},
pages = {142-149},
doi = {10.1016/j.bioelechem.2017.09.012},
pmid = {28992595},
issn = {1878-562X},
mesh = {Archaeoglobales/*chemistry/physiology ; Biofilms ; *Electric Conductivity ; *Electrolysis ; *Temperature ; },
abstract = {Few microorganisms have been examined for current generation under thermophilic (40-65°C) or hyperthermophilic temperatures (≥80°C) in microbial electrochemical systems. Two iron-reducing archaea from the family Archaeoglobaceae, Ferroglobus placidus and Geoglobus ahangari, showed electro-active behavior leading to current generation at hyperthermophilic temperatures in single-chamber microbial electrolysis cells (MECs). A current density (j) of 0.68±0.11A/m2 was attained in F. placidus MECs at 85°C, and 0.57±0.10A/m2 in G. ahangari MECs at 80°C, with an applied voltage of 0.7V. Cyclic voltammetry (CV) showed that both strains produced a sigmoidal catalytic wave, with a mid-point potential of -0.39V (vs. Ag/AgCl) for F. placidus and -0.37V for G. ahangari. The comparison of CVs using spent medium and turnover CVs, coupled with the detection of peaks at the same potentials in both turnover and non-turnover conditions, suggested that mediators were not used for electron transfer and that both archaea produced current through direct contact with the electrode. These two archaeal species, and other hyperthermophilic exoelectrogens, have the potential to broaden the applications of microbial electrochemical technologies for producing biofuels and other bioelectrochemical products under extreme environmental conditions.},
}
@article {pmid28992240,
year = {2017},
author = {Nakamura, T and Oshima, M and Yasuda, M and Shimamura, A and Morita, J and Uegaki, K},
title = {Alteration of molecular assembly of peroxiredoxins from hyperthermophilic archaea.},
journal = {Journal of biochemistry},
volume = {162},
number = {6},
pages = {415-422},
doi = {10.1093/jb/mvx045},
pmid = {28992240},
issn = {1756-2651},
mesh = {Aeropyrum/*chemistry ; Hydrogen Peroxide/pharmacology ; Models, Molecular ; Peroxiredoxins/*chemistry/genetics/metabolism ; Point Mutation/genetics ; Protein Conformation ; Pyrococcus horikoshii/chemistry ; },
abstract = {Peroxiredoxin from Pyrococcus horikoshii (PhPrx) is a decameric protein formed by ring-type assembly of five dimers. To engineer the quaternary structure of PhPrx, we created a mutant PhPrx (PhPrx6m) by introducing six point mutations designed to dissociate PhPrx into dimers. Although PhPrx6m was a dimer in solution, the six dimers assembled into a dodecamer following crystallization. In the crystal structure, PhPrx6m was overoxidized, and the peroxidatic cysteine was in sulfonic acid form and two cysteines in the C-terminal region were linked by an intramolecular disulfide bond. Thus, we characterized the wild-type PhPrx overoxidized by hydrogen peroxide (PhPrxPer). Analytical ultracentrifugation showed that PhPrxPer had a higher molecular mass in solution than PhPrx. This was confirmed by analysis of the crystal structure of PhPrxPer, which was found to form a ring-type dodecamer composed of six dimers. The monomeric structures of PhPrx6m and PhPrxPer differed from that of PhPrx in the relative orientation of two domains, reflecting the number of dimers in the ring-type assembly. Unlike PhPrx, homologous peroxiredoxin from Aeropyrum pernix (ApPrx) did not undergo hexameric association. This property can be explained by the stronger connection between the two domains in ApPrx due to its C-terminal extension relative to PhPrx.},
}
@article {pmid28975058,
year = {2017},
author = {Fuchsman, CA and Collins, RE and Rocap, G and Brazelton, WJ},
title = {Effect of the environment on horizontal gene transfer between bacteria and archaea.},
journal = {PeerJ},
volume = {5},
number = {},
pages = {e3865},
pmid = {28975058},
issn = {2167-8359},
abstract = {BACKGROUND: Horizontal gene transfer, the transfer and incorporation of genetic material between different species of organisms, has an important but poorly quantified role in the adaptation of microbes to their environment. Previous work has shown that genome size and the number of horizontally transferred genes are strongly correlated. Here we consider how genome size confuses the quantification of horizontal gene transfer because the number of genes an organism accumulates over time depends on its evolutionary history and ecological context (e.g., the nutrient regime for which it is adapted).<br><br>RESULTS: We investigated horizontal gene transfer between archaea and bacteria by first counting reciprocal BLAST hits among 448 bacterial and 57 archaeal genomes to find shared genes. Then we used the DarkHorse algorithm, a probability-based, lineage-weighted method (Podell &amp; Gaasterland, 2007), to identify potential horizontally transferred genes among these shared genes. By removing the effect of genome size in the bacteria, we have identified bacteria with unusually large numbers of shared genes with archaea for their genome size. Interestingly, archaea and bacteria that live in anaerobic and/or high temperature conditions are more likely to share unusually large numbers of genes. However, high salt was not found to significantly affect the numbers of shared genes. Numbers of shared (genome size-corrected, reciprocal BLAST hits) and transferred genes (identified by DarkHorse) were strongly correlated. Thus archaea and bacteria that live in anaerobic and/or high temperature conditions are more likely to share horizontally transferred genes. These horizontally transferred genes are over-represented by genes involved in energy conversion as well as the transport and metabolism of inorganic ions and amino acids.<br><br>CONCLUSIONS: Anaerobic and thermophilic bacteria share unusually large numbers of genes with archaea. This is mainly due to horizontal gene transfer of genes from the archaea to the bacteria. In general, these transfers are from archaea that live in similar oxygen and temperature conditions as the bacteria that receive the genes. Potential hotspots of horizontal gene transfer between archaea and bacteria include hot springs, marine sediments, and oil wells. Cold spots for horizontal transfer included dilute, aerobic, mesophilic environments such as marine and freshwater surface waters.},
}
@article {pmid28974619,
year = {2017},
author = {Skennerton, CT and Chourey, K and Iyer, R and Hettich, RL and Tyson, GW and Orphan, VJ},
title = {Erratum for Skennerton et al., &quot;Methane-Fueled Syntrophy through Extracellular Electron Transfer: Uncovering the Genomic Traits Conserved within Diverse Bacterial Partners of Anaerobic Methanotrophic Archaea&quot;.},
journal = {mBio},
volume = {8},
number = {5},
pages = {},
doi = {10.1128/mBio.01561-17},
pmid = {28974619},
issn = {2150-7511},
}
@article {pmid28973467,
year = {2017},
author = {Martinez-Pastor, M and Lancaster, WA and Tonner, PD and Adams, MWW and Schmid, AK},
title = {A transcription network of interlocking positive feedback loops maintains intracellular iron balance in archaea.},
journal = {Nucleic acids research},
volume = {45},
number = {17},
pages = {9990-10001},
pmid = {28973467},
issn = {1362-4962},
mesh = {Archaeal Proteins/*genetics/metabolism ; DNA-Binding Proteins/genetics/metabolism ; *Feedback, Physiological ; *Gene Expression Regulation, Archaeal ; *Gene Regulatory Networks ; Halobacterium salinarum/*genetics/metabolism ; Homeostasis/genetics ; Iron/*metabolism ; Mutation ; Repressor Proteins/genetics/metabolism ; Transcription, Genetic ; },
abstract = {Iron is required for key metabolic processes but is toxic in excess. This circumstance forces organisms across the tree of life to tightly regulate iron homeostasis. In hypersaline lakes dominated by archaeal species, iron levels are extremely low and subject to environmental change; however, mechanisms regulating iron homeostasis in archaea remain unclear. In previous work, we demonstrated that two transcription factors (TFs), Idr1 and Idr2, collaboratively regulate aspects of iron homeostasis in the model species Halobacterium salinarum. Here we show that Idr1 and Idr2 are part of an extended regulatory network of four TFs of the bacterial DtxR family that maintains intracellular iron balance. We demonstrate that each TF directly regulates at least one of the other DtxR TFs at the level of transcription. Dynamical modeling revealed interlocking positive feedback loop architecture, which exhibits bistable or oscillatory network dynamics depending on iron availability. TF knockout mutant phenotypes are consistent with model predictions. Together, our results support that this network regulates iron homeostasis despite variation in extracellular iron levels, consistent with dynamical properties of interlocking feedback architecture in eukaryotes. These results suggest that archaea use bacterial-type TFs in a eukaryotic regulatory network topology to adapt to harsh environments.},
}
@article {pmid28973046,
year = {2017},
author = {Visone, V and Han, W and Perugino, G and Del Monaco, G and She, Q and Rossi, M and Valenti, A and Ciaramella, M},
title = {In vivo and in vitro protein imaging in thermophilic archaea by exploiting a novel protein tag.},
journal = {PloS one},
volume = {12},
number = {10},
pages = {e0185791},
pmid = {28973046},
issn = {1932-6203},
mesh = {Archaea/*metabolism ; Archaeal Proteins/*metabolism ; DNA Topoisomerases, Type I/metabolism ; Hot Temperature ; Sulfolobus/*metabolism ; Sulfolobus solfataricus/*metabolism ; },
abstract = {Protein imaging, allowing a wide variety of biological studies both in vitro and in vivo, is of great importance in modern biology. Protein and peptide tags fused to proteins of interest provide the opportunity to elucidate protein location and functions, detect protein-protein interactions, and measure protein activity and kinetics in living cells. Whereas several tags are suitable for protein imaging in mesophilic organisms, the application of this approach to microorganisms living at high temperature has lagged behind. Archaea provide an excellent and unique model for understanding basic cell biology mechanisms. Here, we present the development of a toolkit for protein imaging in the hyperthermophilic archaeon Sulfolobus islandicus. The system relies on a thermostable protein tag (H5) constructed by engineering the alkylguanine-DNA-alkyl-transferase protein of Sulfolobus solfataricus, which can be covalently labeled using a wide range of small molecules. As a suitable host, we constructed, by CRISPR-based genome-editing technology, a S. islandicus mutant strain deleted for the alkylguanine-DNA-alkyl-transferase gene (Δogt). Introduction of a plasmid-borne H5 gene in this strain led to production of a functional H5 protein, which was successfully labeled with appropriate fluorescent molecules and visualized in cell extracts as well as in Δogt live cells. H5 was fused to reverse gyrase, a peculiar thermophile-specific DNA topoisomerase endowed with positive supercoiling activity, and allowed visualization of the enzyme in living cells. To the best of our knowledge, this is the first report of in vivo imaging of any protein of a thermophilic archaeon, filling an important gap in available tools for cell biology studies in these organisms.},
}
@article {pmid28957503,
year = {2017},
author = {Bobay, LM and Ochman, H},
title = {Impact of Recombination on the Base Composition of Bacteria and Archaea.},
journal = {Molecular biology and evolution},
volume = {34},
number = {10},
pages = {2627-2636},
pmid = {28957503},
issn = {1537-1719},
support = {R01 GM108657/GM/NIGMS NIH HHS/United States ; R35 GM118038/GM/NIGMS NIH HHS/United States ; },
mesh = {Archaea/genetics ; Bacteria/genetics ; Base Composition/*genetics ; Computer Simulation ; Evolution, Molecular ; Gene Conversion ; Genome, Bacterial ; Mutation ; Phylogeny ; Recombination, Genetic/*genetics ; Selection, Genetic ; Sequence Analysis/methods ; },
abstract = {The mutational process in bacteria is biased toward A and T, and most species are GC-rich relative to the mutational input to their genome. It has been proposed that the shift in base composition is an adaptive process-that natural selection operates to increase GC-contents-and there is experimental evidence that bacterial strains with GC-rich versions of genes have higher growth rates than those strains with AT-rich versions expressing identical proteins. Alternatively, a nonadaptive process, GC-biased gene conversion (gBGC), could also increase the GC-content of DNA due to the mechanistic bias of gene conversion events during recombination. To determine what role recombination plays in the base composition of bacterial genomes, we compared the spectrum of nucleotide polymorphisms introduced by recombination in all microbial species represented by large numbers of sequenced strains. We found that recombinant alleles are consistently biased toward A and T, and that the magnitude of AT-bias introduced by recombination is similar to that of mutations. These results indicate that recombination alone, without the intervention of selection, is unlikely to counteract the AT-enrichment of bacterial genomes.},
}
@article {pmid28942710,
year = {2017},
author = {Yamauchi, N and Tanoue, R},
title = {Deuterium incorporation experiments from (3R)- and (3S)-[3-2H]leucine into characteristic isoprenoidal lipid-core of halophilic archaea suggests the involvement of isovaleryl-CoA dehydrogenase.},
journal = {Bioscience, biotechnology, and biochemistry},
volume = {81},
number = {11},
pages = {2062-2070},
doi = {10.1080/09168451.2017.1373588},
pmid = {28942710},
issn = {1347-6947},
mesh = {Deuterium/*chemistry ; Halobacterium salinarum/*metabolism ; Isovaleryl-CoA Dehydrogenase/*metabolism ; Leucine/*chemistry ; Lipid Metabolism ; Lipids/*chemistry ; Terpenes/*chemistry ; },
abstract = {The stereochemical reaction course for the two C-3 hydrogens of leucine to produce a characteristic isoprenoidal lipid in halophilic archaea was observed using incubation experiments with whole cell Halobacterium salinarum. Deuterium-labeled (3R)- and (3S)-[3-2H]leucine were freshly prepared as substrates from 2,3-epoxy-4-methyl-1-pentanol. Incorporation of deuterium from (3S)-[3-2H]leucine and loss of deuterium from (3R)-[3-2H]leucine in the lipid-core of H. salinarum was observed. Taken together with the results of our previous report, involving the incubation of chiral-labeled [5-2H]leucine, these results strongly suggested an involvement of isovaleryl-CoA dehydrogenase in leucine conversion to isoprenoid lipid in halophilic archaea. The stereochemical course of the reaction (anti-elimination) might have been the same as that previously reported for mammalian enzyme reactions. Thus, these results suggested that branched amino acids were metabolized to mevalonate in archaea in a manner similar to other organisms.},
}
@article {pmid28920507,
year = {2018},
author = {Sharma, A and Rani, S and Goel, M},
title = {Navigating the structure-function-evolutionary relationship of CsaA chaperone in archaea.},
journal = {Critical reviews in microbiology},
volume = {44},
number = {3},
pages = {274-289},
doi = {10.1080/1040841X.2017.1357535},
pmid = {28920507},
issn = {1549-7828},
mesh = {Archaea/chemistry/classification/genetics/*metabolism ; Archaeal Proteins/*chemistry/genetics/*metabolism ; *Evolution, Molecular ; Molecular Chaperones/*chemistry/genetics/*metabolism ; Phylogeny ; },
abstract = {CsaA is a protein involved in the post-translational translocation of proteins across the cytoplasmic membrane. It is considered to be a functional homolog of SecB which participates in the Sec-dependent translocation pathway in an analogous manner. CsaA has also been reported to act as a molecular chaperone, preventing aggregation of unfolded proteins. It is essentially a prokaryotic protein which is absent in eukaryotes, but found extensively in bacteria and earlier thought to be widely present in archaea. The study of phylogenetic distribution of CsaA among prokaryotes suggests that it is present only in few archaeal organisms, mainly species of Thermoplasmatales and Halobacteriales. Interestingly, the CsaA protein from these two archaeal orders cluster separately on the phylogenetic tree with CsaA from Gram-positive and Gram-negative bacteria. It, thus, appears that this protein might have been acquired in these archaeal organisms through independent horizontal gene transfer (HGT) events from different bacteria. In this review, we summarize the earlier biochemical, structural, and functional characterization studies of CsaA. We draw new insights into the evolutionary history of this protein through phylogenetic and structural comparison of bacterial CsaA with modelled archaeal CsaA from Picrophilus torridus and Natrialba magadii.},
}
@article {pmid28917104,
year = {2017},
author = {Lee, J and Shin, SG and Han, G and Koo, T and Hwang, S},
title = {Bacteria and archaea communities in full-scale thermophilic and mesophilic anaerobic digesters treating food wastewater: Key process parameters and microbial indicators of process instability.},
journal = {Bioresource technology},
volume = {245},
number = {Pt A},
pages = {689-697},
doi = {10.1016/j.biortech.2017.09.015},
pmid = {28917104},
issn = {1873-2976},
mesh = {Anaerobiosis ; *Archaea ; Bacteria ; Bioreactors ; Methane ; Sewage ; *Waste Water ; },
abstract = {In this study, four different mesophilic and thermophilic full-scale anaerobic digesters treating food wastewater (FWW) were monitored for 1-2years in order to investigate: 1) microbial communities underpinning anaerobic digestion of FWW, 2) significant factors shaping microbial community structures, and 3) potential microbial indicators of process instability. Twenty-seven bacterial genera were identified as abundant bacteria underpinning the anaerobic digestion of FWW. Methanosaeta harundinacea, M. concilii, Methanoculleus bourgensis, M. thermophilus, and Methanobacterium beijingense were revealed as dominant methanogens. Bacterial community structures were clearly differentiated by digesters; archaeal community structures of each digester were dominated by one or two methanogen species. Temperature, ammonia, propionate, Na+, and acetate in the digester were significant factors shaping microbial community structures. The total microbial populations, microbial diversity, and specific bacteria genera showed potential as indicators of process instability in the anaerobic digestion of FWW.},
}
@article {pmid28910647,
year = {2017},
author = {Dai, X and Hu, C and Zhang, D and Dai, L and Duan, N},
title = {Impact of a high ammonia-ammonium-pH system on methane-producing archaea and sulfate-reducing bacteria in mesophilic anaerobic digestion.},
journal = {Bioresource technology},
volume = {245},
number = {Pt A},
pages = {598-605},
doi = {10.1016/j.biortech.2017.08.208},
pmid = {28910647},
issn = {1873-2976},
mesh = {*Ammonia ; Ammonium Compounds ; Anaerobiosis ; *Archaea ; Bacteria, Anaerobic ; Bioreactors ; *Methane ; Sulfates ; },
abstract = {A novel strategy for acclimation to ammonia stress was implemented by stimulating a high ammonia-ammonium-pH environment in a high-solid anaerobic digestion (AD) system in this study. Three semi-continuously stirred anaerobic reactors performed well over the whole study period under mesophilic conditions, especially in experimental group (R-2) when accommodated from acclimation period which the maximum total ammonia nitrogen (TAN) and free ammonia nitrogen (FAN) increased to 4921 and 2996mg/L, respectively. Moreover, when it accommodated the high ammonia-ammonium-pH system, the daily biogas production and methane content were similar to those in R-1 (the blank control to R-2), but the hydrogen sulfide (H2S) content lower than the blank control. Moreover, mechanistic studies showed that high ammonia stress enhanced the activity of coenzyme F420. The results of real-time fluorescent quantitative polymerase chain reaction (PCR) showed that ammonia stress decreased the abundance of sulfate-reducing bacteria and increased the abundance of methane-producing archaea.},
}
@article {pmid28905430,
year = {2017},
author = {McDougall, M and Francisco, O and Harder-Viddal, C and Roshko, R and Meier, M and Stetefeld, J},
title = {Archaea S-layer nanotube from a &quot;black smoker&quot; in complex with cyclo-octasulfur (S8) rings.},
journal = {Proteins},
volume = {85},
number = {12},
pages = {2209-2216},
doi = {10.1002/prot.25385},
pmid = {28905430},
issn = {1097-0134},
mesh = {Amino Acid Motifs ; Archaeal Proteins ; Crystallography, X-Ray ; Desulfurococcaceae/*chemistry/metabolism ; Escherichia coli/genetics/metabolism ; Gene Expression ; Hydrophobic and Hydrophilic Interactions ; Hydrothermal Vents ; Molecular Dynamics Simulation ; Nanotubes/*chemistry/ultrastructure ; Plasmids/chemistry/metabolism ; Protein Interaction Domains and Motifs ; Protein Structure, Secondary ; Recombinant Fusion Proteins/chemistry/genetics/metabolism ; Sulfur/*chemistry/metabolism ; Thermodynamics ; Water/*chemistry/metabolism ; },
abstract = {Elemental sulfur exists primarily as an S80 ring and serves as terminal electron acceptor for a variety of sulfur-fermenting bacteria. Hyperthermophilic archaea from black smoker vents are an exciting research tool to advance our knowledge of sulfur respiration under extreme conditions. Here, we use a hybrid method approach to demonstrate that the proteinaceous cavities of the S-layer nanotube of the hyperthermophilic archaeon Staphylothermus marinus act as a storage reservoir for cyclo-octasulfur S8. Fully atomistic molecular dynamics (MD) simulations were performed and the method of multiconfigurational thermodynamic integration was employed to compute the absolute free energy for transferring a ring of elemental sulfur S8 from an aqueous bath into the largest hydrophobic cavity of a fragment of archaeal tetrabrachion. Comparisons with earlier MD studies of the free energy of hydration as a function of water occupancy in the same cavity of archaeal tetrabrachion show that the sulfur ring is energetically favored over water.},
}
@article {pmid28885627,
year = {2018},
author = {Ino, K and Hernsdorf, AW and Konno, U and Kouduka, M and Yanagawa, K and Kato, S and Sunamura, M and Hirota, A and Togo, YS and Ito, K and Fukuda, A and Iwatsuki, T and Mizuno, T and Komatsu, DD and Tsunogai, U and Ishimura, T and Amano, Y and Thomas, BC and Banfield, JF and Suzuki, Y},
title = {Ecological and genomic profiling of anaerobic methane-oxidizing archaea in a deep granitic environment.},
journal = {The ISME journal},
volume = {12},
number = {1},
pages = {31-47},
pmid = {28885627},
issn = {1751-7370},
mesh = {Anaerobiosis ; Environment ; Genomics ; Groundwater/chemistry/*microbiology ; Methane/*metabolism ; Methanosarcinales/classification/*genetics/isolation &amp; purification/*metabolism ; Nitrates/metabolism ; Oxidation-Reduction ; Phylogeny ; Silicon Dioxide/*analysis/metabolism ; Sulfates/metabolism ; },
abstract = {Recent single-gene-based surveys of deep continental aquifers demonstrated the widespread occurrence of archaea related to Candidatus Methanoperedens nitroreducens (ANME-2d) known to mediate anaerobic oxidation of methane (AOM). However, it is unclear whether ANME-2d mediates AOM in the deep continental biosphere. In this study, we found the dominance of ANME-2d in groundwater enriched in sulfate and methane from a 300-m deep underground borehole in granitic rock. A near-complete genome of one representative species of the ANME-2d obtained from the underground borehole has most of functional genes required for AOM and assimilatory sulfate reduction. The genome of the subsurface ANME-2d is different from those of other members of ANME-2d by lacking functional genes encoding nitrate and nitrite reductases and multiheme cytochromes. In addition, the subsurface ANME-2d genome contains a membrane-bound NiFe hydrogenase gene putatively involved in respiratory H2 oxidation, which is different from those of other methanotrophic archaea. Short-term incubation of microbial cells collected from the granitic groundwater with 13C-labeled methane also demonstrates that AOM is linked to microbial sulfate reduction. Given the prominence of granitic continental crust and sulfate and methane in terrestrial subsurface fluids, we conclude that AOM may be widespread in the deep continental biosphere.},
}
@article {pmid28880150,
year = {2017},
author = {Nayak, DD and Mahanta, N and Mitchell, DA and Metcalf, WW},
title = {Post-translational thioamidation of methyl-coenzyme M reductase, a key enzyme in methanogenic and methanotrophic Archaea.},
journal = {eLife},
volume = {6},
number = {},
pages = {},
pmid = {28880150},
issn = {2050-084X},
support = {R01 GM097142/GM/NIGMS NIH HHS/United States ; },
mesh = {Amides/*chemistry ; Archaea/*enzymology/growth &amp; development ; Binding Sites ; Catalysis ; Methane/*metabolism ; Oxidoreductases/*chemistry/*metabolism ; Phylogeny ; *Protein Processing, Post-Translational ; Sulfhydryl Compounds/*chemistry ; },
abstract = {Methyl-coenzyme M reductase (MCR), found in strictly anaerobic methanogenic and methanotrophic archaea, catalyzes the reversible production and consumption of the potent greenhouse gas methane. The α subunit of MCR (McrA) contains several unusual post-translational modifications, including a rare thioamidation of glycine. Based on the presumed function of homologous genes involved in the biosynthesis of thioviridamide, a thioamide-containing natural product, we hypothesized that the archaeal tfuA and ycaO genes would be responsible for post-translational installation of thioglycine into McrA. Mass spectrometric characterization of McrA from the methanogenic archaeon Methanosarcina acetivorans lacking tfuA and/or ycaO revealed the presence of glycine, rather than thioglycine, supporting this hypothesis. Phenotypic characterization of the ∆ycaO-tfuA mutant revealed a severe growth rate defect on substrates with low free energy yields and at elevated temperatures (39°C - 45°C). Our analyses support a role for thioglycine in stabilizing the protein secondary structure near the active site.},
}
@article {pmid28874471,
year = {2017},
author = {Fu, X and Adams, Z and Liu, R and Hepowit, NL and Wu, Y and Bowmann, CF and Moskovitz, J and Maupin-Furlow, JA},
title = {Methionine Sulfoxide Reductase A (MsrA) and Its Function in Ubiquitin-Like Protein Modification in Archaea.},
journal = {mBio},
volume = {8},
number = {5},
pages = {},
pmid = {28874471},
issn = {2150-7511},
support = {P20 GM103418/GM/NIGMS NIH HHS/United States ; P30 AG035982/AG/NIA NIH HHS/United States ; R01 GM057498/GM/NIGMS NIH HHS/United States ; },
mesh = {Archaea/*enzymology ; Chromatography, Liquid ; Dimethyl Sulfoxide/pharmacology ; Methionine/analogs &amp; derivatives/metabolism ; Methionine Sulfoxide Reductases/biosynthesis/*genetics/*metabolism ; Oxidants/pharmacology ; Oxidative Stress ; Protein Processing, Post-Translational ; Proteolysis ; Tandem Mass Spectrometry ; Ubiquitination ; Ubiquitins/chemistry/*metabolism ; },
abstract = {Methionine sulfoxide reductase A (MsrA) is an antioxidant enzyme found in all domains of life that catalyzes the reduction of methionine-S-sulfoxide (MSO) to methionine in proteins and free amino acids. We demonstrate that archaeal MsrA has a ubiquitin-like (Ubl) protein modification activity that is distinct from its stereospecific reduction of MSO residues. MsrA catalyzes this Ubl modification activity, with the Ubl-activating E1 UbaA, in the presence of the mild oxidant dimethyl sulfoxide (DMSO) and in the absence of reductant. In contrast, the MSO reductase activity of MsrA is inhibited by DMSO and requires reductant. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis reveals that MsrA-dependent Ubl conjugates are associated with DNA replication, protein remodeling, and oxidative stress and include the Ubl-modified MsrA, Orc3 (Orc1/Cdc6), and Cdc48d (Cdc48/p97 AAA+ ATPase). Overall, we found archaeal MsrA to have opposing MSO reductase and Ubl modifying activities that are associated with oxidative stress responses and controlled by exposure to mild oxidant.IMPORTANCE Proteins that are damaged by oxidative stress are often targeted for proteolysis by the ubiquitin-proteasome system (UPS). The mechanisms that control this response are poorly understood, especially under conditions of mild oxidative stress when protein damage is modest. Here, we discovered a novel function of archaeal MsrA in guiding the Ubl modification of target proteins in the presence of mild oxidant. This newly reported activity of MsrA is distinct from its stereospecific reduction of methionine-S-sulfoxide to methionine residues. Our results are significant steps forward, first, in elucidating a protein factor that guides Ubl modification in archaea, and second, in providing an insight into oxidative stress responses that can trigger Ubl modification in a cell.},
}
@article {pmid28853770,
year = {2016},
author = {Kozhevnikova, DA and Taranov, EA and Lebedinsky, AV and Bonch-Osmolovskaya, EA and Sokolova, TG},
title = {Hydrogenogenic and Sulfidogenic Growth of Thermococcus Archaea on Carbon Monoxide and Formate.},
journal = {Mikrobiologiia},
volume = {85},
number = {4},
pages = {381-392},
pmid = {28853770},
issn = {0026-3656},
mesh = {Aldehyde Oxidoreductases/genetics/*metabolism ; Atlantic Ocean ; Carbon Monoxide/*metabolism ; Formate Dehydrogenases/genetics/*metabolism ; Formates/*metabolism ; Gene Expression ; *Genome, Archaeal ; Hot Temperature ; Hydrogen/metabolism ; Hydrothermal Vents ; Kinetics ; Multienzyme Complexes/genetics/*metabolism ; Multigene Family ; Oxidation-Reduction ; Phylogeny ; Seawater ; Sulfur/metabolism ; Thermococcus/classification/genetics/*metabolism ; },
abstract = {Enrichment and pure cultures of hyperthermophilic archaea capable of anaerobic growth on one- carbon compounds (CO and/or formate) were obtained from deep-sea sites of hydrothermal activity at the Mid-Atlantic Ridge, Lau Basin, and Guaymas Basin. All isolates belonged to the T barophilus-T paralvi- .nellae group within the genus Thermococcus. In all cases available for analysis, the genomes of Thermococcus strains capable of growth by hydrogenogenic utilization of CO and/or formate contained clusters of genes en- coding energy-converting hydrogenase and either CO dehydrogenase or formate dehydrogenase and formate transporter. Apart from the previously known processes of hydrogenogenic oxidation of CO and formate, the oxidation of these substrates coupled to sulfur reduction was observed, processes previously unknown among archaea. The capacities for hydrogenogenic or sulfidogenic oxidation of CO and formate occurred in the studied strains in all possible combinations, which could only in part be explained by peculiarities of organi- zation of genetic determinants revealed in the genomes. Investigation of CO and formate consumption kinet- ics revealed that T barophilus strain Ch5 was able to grow at concentrations close to the environmental ones. Thus, it was shown that hyperthermophilic archaea from deep-sea hydrothermal vents are able to utilize one- carbon substrates of abiotic origin both in the presence of an electron acceptor (sulfur) and in its absence. These processes were probably of importance under the conditions of the early Earth biosphere.},
}
@article {pmid28841790,
year = {2017},
author = {Roy, D and McEvoy, J and Blonigen, M and Amundson, M and Khan, E},
title = {Seasonal variation and ex-situ nitrification activity of ammonia oxidizing archaea in biofilm based wastewater treatment processes.},
journal = {Bioresource technology},
volume = {244},
number = {Pt 1},
pages = {850-859},
doi = {10.1016/j.biortech.2017.08.060},
pmid = {28841790},
issn = {1873-2976},
mesh = {Ammonia ; *Archaea ; Bacteria ; Biofilms ; *Nitrification ; Oxidation-Reduction ; Phylogeny ; Seasons ; *Waste Water ; },
abstract = {The abundance of ammonia oxidizing archaea (AOA) and ammonia oxidizing bacteria (AOB) was investigated in full-scale two-stage trickling filters (TF) and moving bed bioreactor (MBBR) treating municipal wastewater. Biofilm samples were collected for 17months from nitrifying TF (NTF), biochemical oxygen demand TF (BTF), and MBBR media. The abundance of AOA and AOB was determined using a quantitative PCR approach targeting the ammonia monooxygenase subunit A gene of archaea and bacteria. AOA were dominant in the NTF and MBBR, while AOB dominated in the BTF. AOA and AOB were more abundant during warmer months, and AOA were detected in the BTF only during warmer months. In laboratory nitrification activity experiments, ammonia oxidation to nitrite decreased when AOA populations from the NTF and MBBR were inhibited, demonstrating that AOA contributed to nitrification. This study has shown that AOA outnumber AOB and contribute to ammonia oxidation in full-scale nitrifying biofilm processes.},
}
@article {pmid28840778,
year = {2017},
author = {Tomita, T},
title = {Structure, function, and regulation of enzymes involved in amino acid metabolism of bacteria and archaea.},
journal = {Bioscience, biotechnology, and biochemistry},
volume = {81},
number = {11},
pages = {2050-2061},
doi = {10.1080/09168451.2017.1365593},
pmid = {28840778},
issn = {1347-6947},
mesh = {Allosteric Regulation ; Amino Acids/*metabolism ; Animals ; Archaea/*enzymology/metabolism ; Bacteria/*enzymology/metabolism ; Glutamate Dehydrogenase/*chemistry/*metabolism ; Humans ; },
abstract = {Amino acids are essential components in all organisms because they are building blocks of proteins. They are also produced industrially and used for various purposes. For example, L-glutamate is used as the component of &quot;umami&quot; taste and lysine has been used as livestock feed. Recently, many kinds of amino acids have attracted attention as biological regulators and are used for a healthy life. Thus, to clarify the mechanism of how amino acids are biosynthesized and how they work as biological regulators will lead to further effective utilization of them. Here, I review the leucine-induced-allosteric activation of glutamate dehydrogenase (GDH) from Thermus thermophilus and the relationship with the allosteric regulation of GDH from mammals. Next, I describe structural insights into the efficient production of L-glutamate by GDH from an excellent L-glutamate producer, Corynebacterium glutamicum. Finally, I review the structural biology of lysine biosynthesis of thermophilic bacterium and archaea.},
}
@article {pmid28837073,
year = {2017},
author = {Yi, GS and Song, Y and Wang, WW and Chen, JN and Deng, W and Cao, W and Wang, FP and Xiao, X and Liu, XP},
title = {Two Archaeal RecJ Nucleases from Methanocaldococcus jannaschii Show Reverse Hydrolysis Polarity: Implication to Their Unique Function in Archaea.},
journal = {Genes},
volume = {8},
number = {9},
pages = {},
pmid = {28837073},
issn = {2073-4425},
abstract = {Bacterial nuclease RecJ, which exists in almost all bacterial species, specifically degrades single-stranded (ss) DNA in the 5' to 3' direction. Some archaeal phyla, except Crenarchaea, also encode RecJ homologs. Compared with bacterial RecJ, archaeal RecJ exhibits a largely different amino acid sequence and domain organization. Archaeal RecJs from Thermococcus kodakarensis and Pyrococcus furiosus show 5'→3' exonuclease activity on ssDNA. Interestingly, more than one RecJ exists in some Euryarchaeota classes, such as Methanomicrobia, Methanococci, Methanomicrobia, Methanobacteria, and Archaeoglobi. Here we report the biochemical characterization of two RecJs from Methanocaldococcus jannaschii, the long RecJ1 (MJ0977) and short RecJ2 (MJ0831) to understand their enzymatic properties. RecJ1 is a 5'→3' exonuclease with a preference to ssDNA; however, RecJ2 is a 3'→5' exonuclease with a preference to ssRNA. The 5' terminal phosphate promotes RecJ1 activity, but the 3' terminal phosphate inhibits RecJ2 nuclease. Go-Ichi-Ni-San (GINS) complex does not interact with two RecJs and does not promote their nuclease activities. Finally, we discuss the diversity, function, and molecular evolution of RecJ in archaeal taxonomy. Our analyses provide insight into the function and evolution of conserved archaeal RecJ/eukaryotic Cdc45 protein.},
}
@article {pmid28826642,
year = {2018},
author = {Moissl-Eichinger, C and Pausan, M and Taffner, J and Berg, G and Bang, C and Schmitz, RA},
title = {Archaea Are Interactive Components of Complex Microbiomes.},
journal = {Trends in microbiology},
volume = {26},
number = {1},
pages = {70-85},
doi = {10.1016/j.tim.2017.07.004},
pmid = {28826642},
issn = {1878-4380},
mesh = {Animals ; Archaea/classification/*physiology ; Biodiversity ; Biofilms ; Ecology ; Ecosystem ; Eukaryota ; Euryarchaeota ; Gastrointestinal Microbiome ; Gastrointestinal Tract/microbiology ; Halobacteriales ; Health ; Humans ; Microbial Consortia ; Microbial Interactions/*physiology ; Microbiota/*physiology ; Mouth/microbiology ; Phylogeny ; Plants/microbiology ; Ruminants/microbiology ; Soil Microbiology ; Symbiosis ; Viruses ; },
abstract = {Recent findings have shaken our picture of the biology of the archaea and revealed novel traits beyond archaeal extremophily and supposed 'primitiveness'. The archaea constitute a considerable fraction of the Earth's ecosystems, and their potential to shape their surroundings by a profound interaction with their biotic and abiotic environment has been recognized. Moreover, archaea have been identified as a substantial component, or even as keystone species, in complex microbiomes - in the environment or accompanying a holobiont. Species of the Euryarchaeota (methanogens, halophiles) and Thaumarchaeota, in particular, have the capacity to coexist in plant, animal, and human microbiomes, where syntrophy allows them to thrive under energy-deficiency stress. Due to methodological limitations, the archaeome remains mysterious, and many questions with respect to potential pathogenicity, function, and structural interactions with their host and other microorganisms remain.},
}
@article {pmid28826405,
year = {2017},
author = {Gilmore, SP and Henske, JK and Sexton, JA and Solomon, KV and Seppälä, S and Yoo, JI and Huyett, LM and Pressman, A and Cogan, JZ and Kivenson, V and Peng, X and Tan, Y and Valentine, DL and O'Malley, MA},
title = {Genomic analysis of methanogenic archaea reveals a shift towards energy conservation.},
journal = {BMC genomics},
volume = {18},
number = {1},
pages = {639},
pmid = {28826405},
issn = {1471-2164},
mesh = {Anaerobiosis ; Archaeal Proteins/metabolism ; Energy Metabolism/*genetics ; *Genomics ; Methane/*biosynthesis ; Methanobacterium/*genetics/*metabolism ; },
abstract = {BACKGROUND: The metabolism of archaeal methanogens drives methane release into the environment and is critical to understanding global carbon cycling. Methanogenesis operates at a very low reducing potential compared to other forms of respiration and is therefore critical to many anaerobic environments. Harnessing or altering methanogen metabolism has the potential to mitigate global warming and even be utilized for energy applications.<br><br>RESULTS: Here, we report draft genome sequences for the isolated methanogens Methanobacterium bryantii, Methanosarcina spelaei, Methanosphaera cuniculi, and Methanocorpusculum parvum. These anaerobic, methane-producing archaea represent a diverse set of isolates, capable of methylotrophic, acetoclastic, and hydrogenotrophic methanogenesis. Assembly and analysis of the genomes allowed for simple and rapid reconstruction of metabolism in the four methanogens. Comparison of the distribution of Clusters of Orthologous Groups (COG) proteins to a sample of genomes from the RefSeq database revealed a trend towards energy conservation in genome composition of all methanogens sequenced. Further analysis of the predicted membrane proteins and transporters distinguished differing energy conservation methods utilized during methanogenesis, such as chemiosmotic coupling in Msar. spelaei and electron bifurcation linked to chemiosmotic coupling in Mbac. bryantii and Msph. cuniculi.<br><br>CONCLUSIONS: Methanogens occupy a unique ecological niche, acting as the terminal electron acceptors in anaerobic environments, and their genomes display a significant shift towards energy conservation. The genome-enabled reconstructed metabolisms reported here have significance to diverse anaerobic communities and have led to proposed substrate utilization not previously reported in isolation, such as formate and methanol metabolism in Mbac. bryantii and CO2 metabolism in Msph. cuniculi. The newly proposed substrates establish an important foundation with which to decipher how methanogens behave in native communities, as CO2 and formate are common electron carriers in microbial communities.},
}
@article {pmid28812261,
year = {2017},
author = {Xuan, J and Yao, H and Feng, Y and Wang, J},
title = {Backbone and side-chain 1H, 15N and 13C resonance assignments of two Sac10b family members Mvo10b and Mth10bTQQA from archaea.},
journal = {Biomolecular NMR assignments},
volume = {11},
number = {2},
pages = {269-273},
doi = {10.1007/s12104-017-9761-8},
pmid = {28812261},
issn = {1874-270X},
support = {31300635//National Natural Science Foundation of China/ ; 31670735//National Natural Science Foundation of China/ ; 30770434//National Natural Science Foundation of China/ ; },
mesh = {Archaeal Proteins/*chemistry ; DNA-Binding Proteins/*chemistry ; *Nuclear Magnetic Resonance, Biomolecular ; },
abstract = {The Sac10b family proteins, also named as Alba, are small, basic, nucleic acid-binding proteins widely distributed in archaea. They possess divergent physiological functions such as binding to both DNA and RNA with a high affinity and involving in genomic DNA compaction, RNA transactions and transcriptional regulations. The structures of many Sac10b family proteins from hyperthermophilic archaea have been reported, while those from thermophilic and mesophilic archaea are largely unknown. As was pointed out, the homologous members from thermophilic and mesophilic archaea may have functions different from the hyperthermophilic members. Therefore, comparison of these homologous members can provide biophysical and structural insight into the functional diversity and thermal adaptation mechanism. The present work mainly focused on the NMR study of two Sac10b family members, Mvo10b and Mth10b, from the mesophilic and thermophilic archaea, respectively. To overcome the difficulties caused by the oligomerization and conformation heterogeneity of Mth10b, a M13T/L17Q/I20Q/P56A mutant Mth10b (Mth10bTQQA) was constructed and used together with Mvo10b for multi-dimensional NMR experiments. The resonance assignments of Mvo10b and Mth10bTQQA are reported for further structural determination which is a basis for understanding the functional diversity and their thermal adaption mechanisms.},
}
@article {pmid28808742,
year = {2017},
author = {Wu, RN and Meng, H and Wang, YF and Lan, W and Gu, JD},
title = {A More Comprehensive Community of Ammonia-Oxidizing Archaea (AOA) Revealed by Genomic DNA and RNA Analyses of amoA Gene in Subtropical Acidic Forest Soils.},
journal = {Microbial ecology},
volume = {74},
number = {4},
pages = {910-922},
pmid = {28808742},
issn = {1432-184X},
mesh = {Ammonia/metabolism ; Archaea/classification/*physiology ; Archaeal Proteins/*analysis ; China ; Cunninghamia/growth &amp; development ; *Forestry ; Forests ; *Microbiota ; Oxidation-Reduction ; Phylogeny ; *Soil Microbiology ; },
abstract = {Ammonia-oxidizing bacteria (AOB) and archaea (AOA) are the main nitrifiers which are well studied in natural environments, and AOA frequently outnumber AOB by orders especially in acidic conditions, making AOA the most promising ammonia oxidizers. The phylogeny of AOA revealed in related studies, however, often varied and hardly reach a consensus on functional phylotypes. The objective of this study was to compare ammonia-oxidizing communities by amoA gene and transcript based on both genomic DNA and RNA in extremely acidic forest soils (pH <4.5). Our results support the numerical and functional dominance of AOA over AOB in acidic soils as bacterial amoA gene and transcript were both under detection limits and archaeal amoA, in contrast, were abundant and responded to the fluctuations of environmental factors. Organic matter from tree residues was proposed as the main source of microbial available nitrogen, and the potential co-precipitation of dissolved organic matter (DOM) with soluble Al3+ species in acidic soil matrix may further restrict the amount of nitrogen sources required by AOB besides NH3/NH4+ equilibrium. Although AOA were better adapted to oligotrophic environments, they were susceptible to the toxicity of exchangeable Al3+. Phylotypes affiliated to Nitrososphaera, Nitrososphaera sister group, and Nitrosotalea were detected by amoA gene and transcript. Nitrosotalea devantaerra and Nitrososphaera sister group were the major AOA. Compared to the genomic DNA data, higher relative abundances of Nitrososphaera and Nitrososphaera sister group were recognized in amoA transcript inferred AOA communities, where Nitrosotalea relative abundance was found lower, implying the functional activities of Nitrososphaera sister group and Nitrososphaera were easily underestimated and Nitrosotalea did not attribute proportionally to nitrification in extremely acidic soils. Further comparison of the different AOA community compositions and relative abundance of each phylotypes revealed by amoA genes and transcripts make it possible to identify the functional AOA species and assess their ecological role in extremely acidic soils.},
}
@article {pmid28798133,
year = {2017},
author = {Mattiroli, F and Bhattacharyya, S and Dyer, PN and White, AE and Sandman, K and Burkhart, BW and Byrne, KR and Lee, T and Ahn, NG and Santangelo, TJ and Reeve, JN and Luger, K},
title = {Structure of histone-based chromatin in Archaea.},
journal = {Science (New York, N.Y.)},
volume = {357},
number = {6351},
pages = {609-612},
pmid = {28798133},
issn = {1095-9203},
support = {R01 GM114594/GM/NIGMS NIH HHS/United States ; R01 GM053185/GM/NIGMS NIH HHS/United States ; /HHMI/Howard Hughes Medical Institute/United States ; R01 GM067777/GM/NIGMS NIH HHS/United States ; R01 GM100329/GM/NIGMS NIH HHS/United States ; },
mesh = {Amino Acid Substitution ; Chromatin/chemistry/*ultrastructure ; Crystallography, X-Ray ; DNA, Archaeal/chemistry/ultrastructure ; Gene Expression Regulation, Archaeal ; Glycine/genetics ; Histones/chemistry/*ultrastructure ; Nucleosomes/chemistry/ultrastructure ; Protein Multimerization ; *Thermococcus/chemistry/genetics/growth &amp; development ; Transcription, Genetic ; },
abstract = {Small basic proteins present in most Archaea share a common ancestor with the eukaryotic core histones. We report the crystal structure of an archaeal histone-DNA complex. DNA wraps around an extended polymer, formed by archaeal histone homodimers, in a quasi-continuous superhelix with the same geometry as DNA in the eukaryotic nucleosome. Substitutions of a conserved glycine at the interface of adjacent protein layers destabilize archaeal chromatin, reduce growth rate, and impair transcription regulation, confirming the biological importance of the polymeric structure. Our data establish that the histone-based mechanism of DNA compaction predates the nucleosome, illuminating the origin of the nucleosome.},
}
@article {pmid28794466,
year = {2017},
author = {Cavazzini, D and Grossi, G and Levati, E and Vallese, F and Montanini, B and Bolchi, A and Zanotti, G and Ottonello, S},
title = {A family of archaea-like carboxylesterases preferentially expressed in the symbiotic phase of the mychorrizal fungus Tuber melanosporum.},
journal = {Scientific reports},
volume = {7},
number = {1},
pages = {7628},
pmid = {28794466},
issn = {2045-2322},
mesh = {Ascomycota/*enzymology/*physiology ; Carboxylic Ester Hydrolases/chemistry/genetics/*metabolism ; Catalytic Domain ; Enzyme Stability ; Hot Temperature ; Mycorrhizae/*enzymology/*physiology ; Protein Conformation ; Protein Folding ; Protein Multimerization ; Static Electricity ; Substrate Specificity ; *Symbiosis ; X-Ray Diffraction ; },
abstract = {An increasing number of esterases is being revealed by (meta) genomic sequencing projects, but few of them are functionally/structurally characterized, especially enzymes of fungal origin. Starting from a three-member gene family of secreted putative &quot;lipases/esterases&quot; preferentially expressed in the symbiotic phase of the mycorrhizal fungus Tuber melanosporum (&quot;black truffle&quot;), we show here that these enzymes (TmelEST1-3) are dimeric, heat-resistant carboxylesterases capable of hydrolyzing various short/medium chain p-nitrophenyl esters. TmelEST2 was the most active (kcat = 2302 s-1 for p-nitrophenyl-butyrate) and thermally stable (T50 = 68.3 °C), while TmelEST3 was the only one displaying some activity on tertiary alcohol esters. X-ray diffraction analysis of TmelEST2 revealed a classical α/β hydrolase-fold structure, with a network of dimer-stabilizing intermolecular interactions typical of archaea esterases. The predicted structures of TmelEST1 and 3 are overall quite similar to that of TmelEST2 but with some important differences. Most notably, the much smaller volume of the substrate-binding pocket and the more acidic electrostatic surface profile of TmelEST1. This was also the only TmelEST capable of hydrolyzing feruloyl-esters, suggestinng a possible role in root cell-wall deconstruction during symbiosis establishment. In addition to their potential biotechnological interest, TmelESTs raise important questions regarding the evolutionary recruitment of archaea-like enzymes into mesophilic subterranean fungi such as truffles.},
}
@article {pmid28790990,
year = {2017},
author = {Chen, J and Nie, Y and Liu, W and Wang, Z and Shen, W},
title = {Ammonia-Oxidizing Archaea Are More Resistant Than Denitrifiers to Seasonal Precipitation Changes in an Acidic Subtropical Forest Soil.},
journal = {Frontiers in microbiology},
volume = {8},
number = {},
pages = {1384},
pmid = {28790990},
issn = {1664-302X},
abstract = {Seasonal precipitation changes are increasingly severe in subtropical areas. However, the responses of soil nitrogen (N) cycle and its associated functional microorganisms to such precipitation changes remain unclear. In this study, two projected precipitation patterns were manipulated: intensifying the dry-season drought (DD) and extending the dry-season duration (ED) but increasing the wet-season storms following the DD and ED treatment period. The effects of these two contrasting precipitation patterns on soil net N transformation rates and functional gene abundances were quantitatively assessed through a resistance index. Results showed that the resistance index of functional microbial abundance (-0.03 ± 0.08) was much lower than that of the net N transformation rate (0.55 ± 0.02) throughout the experiment, indicating that microbial abundance was more responsive to precipitation changes compared with the N transformation rate. Spring drought under the ED treatment significantly increased the abundances of both nitrifying (amoA) and denitrifying genes (nirK, nirS, and nosZ), while changes in these gene abundances overlapped largely with control treatment during droughts in the dry season. Interestingly, the resistance index of the ammonia-oxidizing archaea (AOA) amoA abundance was significantly higher than that of the denitrifying gene abundances, suggesting that AOA were more resistant to the precipitation changes. This was attributed to the stronger environmental adaptability and higher resource utilization efficiency of the AOA community, as indicated by the lack of correlations between AOA gene abundance and environmental factors [i.e., soil water content, ammonium (NH4+) and dissolved organic carbon concentrations] during the experiment.},
}
@article {pmid28787424,
year = {2017},
author = {Bowers, RM and Kyrpides, NC and Stepanauskas, R and Harmon-Smith, M and Doud, D and Reddy, TBK and Schulz, F and Jarett, J and Rivers, AR and Eloe-Fadrosh, EA and Tringe, SG and Ivanova, NN and Copeland, A and Clum, A and Becraft, ED and Malmstrom, RR and Birren, B and Podar, M and Bork, P and Weinstock, GM and Garrity, GM and Dodsworth, JA and Yooseph, S and Sutton, G and Glöckner, FO and Gilbert, JA and Nelson, WC and Hallam, SJ and Jungbluth, SP and Ettema, TJG and Tighe, S and Konstantinidis, KT and Liu, WT and Baker, BJ and Rattei, T and Eisen, JA and Hedlund, B and McMahon, KD and Fierer, N and Knight, R and Finn, R and Cochrane, G and Karsch-Mizrachi, I and Tyson, GW and Rinke, C and , and Lapidus, A and Meyer, F and Yilmaz, P and Parks, DH and Eren, AM and Schriml, L and Banfield, JF and Hugenholtz, P and Woyke, T},
title = {Minimum information about a single amplified genome (MISAG) and a metagenome-assembled genome (MIMAG) of bacteria and archaea.},
journal = {Nature biotechnology},
volume = {35},
number = {8},
pages = {725-731},
pmid = {28787424},
issn = {1546-1696},
support = {310039//European Research Council/International ; R01 AI123037/AI/NIAID NIH HHS/United States ; R01 DE024463/DE/NIDCR NIH HHS/United States ; },
mesh = {Genome, Archaeal/*genetics ; Genome, Bacterial/genetics ; Genomics/*methods/standards ; Metagenomics/*methods/standards ; Sequence Analysis, DNA ; },
abstract = {We present two standards developed by the Genomic Standards Consortium (GSC) for reporting bacterial and archaeal genome sequences. Both are extensions of the Minimum Information about Any (x) Sequence (MIxS). The standards are the Minimum Information about a Single Amplified Genome (MISAG) and the Minimum Information about a Metagenome-Assembled Genome (MIMAG), including, but not limited to, assembly quality, and estimates of genome completeness and contamination. These standards can be used in combination with other GSC checklists, including the Minimum Information about a Genome Sequence (MIGS), Minimum Information about a Metagenomic Sequence (MIMS), and Minimum Information about a Marker Gene Sequence (MIMARKS). Community-wide adoption of MISAG and MIMAG will facilitate more robust comparative genomic analyses of bacterial and archaeal diversity.},
}
@article {pmid28784816,
year = {2017},
author = {Peck, RF and Pleşa, AM and Graham, SM and Angelini, DR and Shaw, EL},
title = {Opsin-Mediated Inhibition of Bacterioruberin Synthesis in Halophilic Archaea.},
journal = {Journal of bacteriology},
volume = {199},
number = {21},
pages = {},
pmid = {28784816},
issn = {1098-5530},
support = {P20 GM103423/GM/NIGMS NIH HHS/United States ; R15 GM094735/GM/NIGMS NIH HHS/United States ; },
mesh = {Archaea/*metabolism ; Bacteriorhodopsins/genetics/*metabolism ; Carotenoids/*biosynthesis ; Cloning, Molecular ; Colorimetry ; Gene Expression ; Haloarcula/enzymology/genetics ; Haloferax volcanii/genetics/*metabolism ; Recombinant Proteins/genetics/metabolism ; Retinaldehyde/metabolism ; },
abstract = {Halophilic archaea often inhabit environments with limited oxygen, and many produce ion-pumping rhodopsin complexes that allow them to maintain electrochemical gradients when aerobic respiration is inhibited. Rhodopsins require a protein, an opsin, and an organic cofactor, retinal. We previously demonstrated that in Halobacterium salinarum, bacterioopsin (BO), when not bound by retinal, inhibits the production of bacterioruberin, a biochemical pathway that shares intermediates with retinal biosynthesis. In this work, we used heterologous expression in a related halophilic archaeon, Haloferax volcanii, to demonstrate that BO is sufficient to inhibit bacterioruberin synthesis catalyzed by the H. salinarum lycopene elongase (Lye) enzyme. This inhibition was observed both in liquid culture and in a novel colorimetric assay to quantify bacterioruberin abundance based on the colony color. Addition of retinal to convert BO to the bacteriorhodopsin complex resulted in a partial rescue of bacterioruberin production. To explore if this regulatory mechanism occurs in other organisms, we expressed a Lye homolog and an opsin from Haloarcula vallismortis in H. volcaniiH. vallismortis cruxopsin-3 expression inhibited bacterioruberin synthesis catalyzed by H. vallismortis Lye but had no effect when bacterioruberin synthesis was catalyzed by H. salinarum or H. volcanii Lye. Conversely, H. salinarum BO did not inhibit H. vallismortis Lye activity. Together, our data suggest that opsin-mediated inhibition of Lye is potentially widespread and represents an elegant regulatory mechanism that allows organisms to efficiently utilize ion-pumping rhodopsins obtained through lateral gene transfer.IMPORTANCE Many enzymes are complexes of proteins and nonprotein organic molecules called cofactors. To ensure efficient formation of functional complexes, organisms must regulate the production of proteins and cofactors. To study this regulation, we used bacteriorhodopsin from the archaeon Halobacterium salinarum Bacteriorhodopsin consists of the bacterioopsin protein and a retinal cofactor. In this article, we further characterize a novel regulatory mechanism in which bacterioopsin promotes retinal production by inhibiting a reaction that consumes lycopene, a retinal precursor. By expressing H. salinarum genes in a different organism, Haloferax volcanii, we demonstrated that bacterioopsin alone is sufficient for this inhibition. We also found that an opsin from Haloarcula vallismortis has inhibitory activity, suggesting that this regulatory mechanism might be found in other organisms.},
}
@article {pmid28783564,
year = {2017},
author = {Barros, VG and Duda, RM and Vantini, JDS and Omori, WP and Ferro, MIT and Oliveira, RA},
title = {Improved methane production from sugarcane vinasse with filter cake in thermophilic UASB reactors, with predominance of Methanothermobacter and Methanosarcina archaea and Thermotogae bacteria.},
journal = {Bioresource technology},
volume = {244},
number = {Pt 1},
pages = {371-381},
doi = {10.1016/j.biortech.2017.07.106},
pmid = {28783564},
issn = {1873-2976},
mesh = {Anaerobiosis ; *Archaea ; Bacteria ; *Bioreactors ; *Methane ; *Methanobacteriaceae ; *Methanosarcina ; Saccharum ; },
abstract = {Biogas production from sugarcane vinasse has enormous economic, energy, and environmental management potential. However, methane production stability and biodigested vinasse quality remain key issues, requiring better nutrient and alkalinity availability, operational strategies, and knowledge of reactor microbiota. This study demonstrates increased methane production from vinasse through the use of sugarcane filter cake and improved effluent recirculation, with elevated organic loading rates (OLR) and good reactor stability. We used UASB reactors in a two-stage configuration, with OLRs up to 45gCODL-1d-1, and obtained methane production as high as 3LL-1d-1. Quantitative PCR indicated balanced amounts of bacteria and archaea in the sludge (109-1010copiesg-1VS), and of the predominant archaea orders, Methanobacteriales and Methanosarcinales (106-108copiesg-1VS). 16S rDNA sequencing also indicated the thermophilic Thermotogae as the most abundant class of bacteria in the sludge.},
}
@article {pmid28779290,
year = {2017},
author = {Vaksmaa, A and Guerrero-Cruz, S and van Alen, TA and Cremers, G and Ettwig, KF and Lüke, C and Jetten, MSM},
title = {Enrichment of anaerobic nitrate-dependent methanotrophic 'Candidatus Methanoperedens nitroreducens' archaea from an Italian paddy field soil.},
journal = {Applied microbiology and biotechnology},
volume = {101},
number = {18},
pages = {7075-7084},
pmid = {28779290},
issn = {1432-0614},
support = {VENI 863.13.007//Nederlandse Organisatie voor Wetenschappelijk Onderzoek/ ; SIAM 024002002//Gravitation grant SIAM/ ; NESSC 024001001//Gravitation grant NESSC/ ; AG 339880 Eco_MoM//European Research Council/International ; 13178//Stichting voor de Technische Wetenschappen/ ; },
mesh = {Anaerobiosis ; Archaea/genetics/growth &amp; development/*isolation &amp; purification/metabolism ; Bioreactors ; Genome, Archaeal/*genetics ; Methane/*metabolism ; Molecular Sequence Annotation ; Nitrates/*metabolism ; Nitrites/*metabolism ; Oxidation-Reduction ; Phylogeny ; Sequence Analysis, DNA ; Soil ; Wetlands ; },
abstract = {Paddy fields are a significant source of methane and contribute up to 20% of total methane emissions from wetland ecosystems. These inundated, anoxic soils featuring abundant nitrogen compounds and methane are an ideal niche for nitrate-dependent anaerobic methanotrophs. After 2 years of enrichment with a continuous supply of methane and nitrate as the sole electron donor and acceptor, a stable enrichment dominated by 'Candidatus Methanoperedens nitroreducens' archaea and 'Candidatus Methylomirabilis oxyfera' NC10 phylum bacteria was achieved. In this community, the methanotrophic archaea supplied the NC10 phylum bacteria with the necessary nitrite through nitrate reduction coupled to methane oxidation. The results of qPCR quantification of 16S ribosomal RNA (rRNA) gene copies, analysis of metagenomic 16S rRNA reads, and fluorescence in situ hybridization (FISH) correlated well and showed that after 2 years, 'Candidatus Methanoperedens nitroreducens' had the highest abundance of (2.2 ± 0.4 × 108) 16S rRNA copies per milliliter and constituted approximately 22% of the total microbial community. Phylogenetic analysis showed that the 16S rRNA genes of the dominant microorganisms clustered with previously described 'Candidatus Methanoperedens nitroreducens ANME2D' (96% identity) and 'Candidatus Methylomirabilis oxyfera' (99% identity) strains. The pooled metagenomic sequences resulted in a high-quality draft genome assembly of 'Candidatus Methanoperedens nitroreducens Vercelli' that contained all key functional genes for the reverse methanogenesis pathway and nitrate reduction. The diagnostic mcrA gene was 96% similar to 'Candidatus Methanoperedens nitroreducens ANME2D' (WP_048089615.1) at the protein level. The 'Candidatus Methylomirabilis oxyfera' draft genome contained the marker genes pmoCAB, mdh, and nirS and putative NO dismutase genes. Whole-reactor anaerobic activity measurements with methane and nitrate revealed an average methane oxidation rate of 0.012 mmol/h/L, with cell-specific methane oxidation rates up to 0.57 fmol/cell/day for 'Candidatus Methanoperedens nitroreducens'. In summary, this study describes the first enrichment and draft genome of methanotrophic archaea from paddy field soil, where these organisms can contribute significantly to the mitigation of methane emissions.},
}
@article {pmid28777382,
year = {2017},
author = {Adam, PS and Borrel, G and Brochier-Armanet, C and Gribaldo, S},
title = {The growing tree of Archaea: new perspectives on their diversity, evolution and ecology.},
journal = {The ISME journal},
volume = {11},
number = {11},
pages = {2407-2425},
pmid = {28777382},
issn = {1751-7370},
mesh = {Archaea/*classification/genetics/*isolation &amp; purification ; *Biodiversity ; Ecology ; Genome, Archaeal ; Phylogeny ; },
abstract = {The Archaea occupy a key position in the Tree of Life, and are a major fraction of microbial diversity. Abundant in soils, ocean sediments and the water column, they have crucial roles in processes mediating global carbon and nutrient fluxes. Moreover, they represent an important component of the human microbiome, where their role in health and disease is still unclear. The development of culture-independent sequencing techniques has provided unprecedented access to genomic data from a large number of so far inaccessible archaeal lineages. This is revolutionizing our view of the diversity and metabolic potential of the Archaea in a wide variety of environments, an important step toward understanding their ecological role. The archaeal tree is being rapidly filled up with new branches constituting phyla, classes and orders, generating novel challenges for high-rank systematics, and providing key information for dissecting the origin of this domain, the evolutionary trajectories that have shaped its current diversity, and its relationships with Bacteria and Eukarya. The present picture is that of a huge diversity of the Archaea, which we are only starting to explore.},
}
@article {pmid28777072,
year = {2017},
author = {Rivera-Gómez, N and Martínez-Núñez, MA and Pastor, N and Rodriguez-Vazquez, K and Perez-Rueda, E},
title = {Dissecting the protein architecture of DNA-binding transcription factors in bacteria and archaea.},
journal = {Microbiology (Reading, England)},
volume = {163},
number = {8},
pages = {1167-1178},
doi = {10.1099/mic.0.000504},
pmid = {28777072},
issn = {1465-2080},
mesh = {Archaea/chemistry/classification/genetics/*metabolism ; Archaeal Proteins/chemistry/genetics/*metabolism ; Bacteria/chemistry/classification/genetics/*metabolism ; Bacterial Proteins/chemistry/genetics/*metabolism ; DNA-Binding Proteins/chemistry/genetics/*metabolism ; Dimerization ; Genome, Archaeal ; Genome, Bacterial ; Models, Molecular ; Phylogeny ; Protein Conformation ; Transcription Factors/chemistry/genetics/*metabolism ; },
abstract = {Gene regulation at the transcriptional level is a central process in all organisms where DNA-binding transcription factors play a fundamental role. This class of proteins binds specifically at DNA sequences, activating or repressing gene expression as a function of the cell's metabolic status, operator context and ligand-binding status, among other factors, through the DNA-binding domain (DBD). In addition, TFs may contain partner domains (PaDos), which are involved in ligand binding and protein-protein interactions. In this work, we systematically evaluated the distribution, abundance and domain organization of DNA-binding TFs in 799 non-redundant bacterial and archaeal genomes. We found that the distributions of the DBDs and their corresponding PaDos correlated with the size of the genome. We also identified specific combinations between the DBDs and their corresponding PaDos. Within each class of DBDs there are differences in the actual angle formed at the dimerization interface, responding to the presence/absence of ligands and/or crystallization conditions, setting the orientation of the resulting helices and wings facing the DNA. Our results highlight the importance of PaDos as central elements that enhance the diversity of regulatory functions in all bacterial and archaeal organisms, and our results also demonstrate the role of PaDos in sensing diverse signal compounds. The highly specific interactions between DBDs and PaDos observed in this work, together with our structural analysis highlighting the difficulty in predicting both inter-domain geometry and quaternary structure, suggest that these systems appeared once and evolved with diverse duplication events in all the analysed organisms.},
}
@article {pmid28776097,
year = {2017},
author = {Zhao, K and Kong, W and Khan, A and Liu, J and Guo, G and Muhanmmad, S and Zhang, X and Dong, X},
title = {Elevational diversity and distribution of ammonia-oxidizing archaea community in meadow soils on the Tibetan Plateau.},
journal = {Applied microbiology and biotechnology},
volume = {101},
number = {18},
pages = {7065-7074},
doi = {10.1007/s00253-017-8435-x},
pmid = {28776097},
issn = {1432-0614},
support = {XDB15010203//Chinese Academy of Sciences/ ; KZZD-EW-TZ-14//Chinese Academy of Sciences/ ; 41471054//National Natural Science Foundation of China/ ; 41401287//National Natural Science Foundation of China/ ; },
mesh = {Ammonia/*metabolism ; Archaea/*metabolism ; Grassland ; Nitrification ; Oxidation-Reduction ; Polymorphism, Restriction Fragment Length ; Soil ; Tibet ; },
abstract = {Unraveling elevational diversity patterns of plants and animals has long been attracting scientific interests. However, whether soil microorganisms exhibit similar elevational patterns remains largely less explored, especially for functional microbial communities, such as ammonia oxidizers. Here, we investigated the diversity and distribution pattern of ammonia-oxidizing archaea (AOA) in meadow soils along an elevation gradient from 4400 m to the grassline at 5100 m on the Tibetan Plateau using terminal restriction fragment length polymorphism (T-RFLP) and sequencing methods by targeting amoA gene. Increasing elevations led to lower soil temperature and pH, but higher nutrients and water content. The results showed that AOA diversity and evenness monotonically increased with elevation, while richness was relatively stable. The increase of diversity and evenness was attributed to the growth inhibition of warm-adapted AOA phylotypes by lower temperature and the growth facilitation of cold-adapted AOA phylotypes by richer nutrients at higher elevations. Low temperature thus played an important role in the AOA growth and niche separation. The AOA community variation was explained by the combined effect of all soil properties (32.6%), and 8.1% of the total variation was individually explained by soil pH. The total AOA abundance decreased, whereas soil potential nitrification rate (PNR) increased with increasing elevations. Soil PNR positively correlated with the abundance of cold-adapted AOA phylotypes. Our findings suggest that low temperature plays an important role in AOA elevational diversity pattern and niche separation, rising the negative effects of warming on AOA diversity and soil nitrification process in the Tibetan region.},
}
@article {pmid28769904,
year = {2017},
author = {Wen, X and Yang, S and Horn, F and Winkel, M and Wagner, D and Liebner, S},
title = {Global Biogeographic Analysis of Methanogenic Archaea Identifies Community-Shaping Environmental Factors of Natural Environments.},
journal = {Frontiers in microbiology},
volume = {8},
number = {},
pages = {1339},
pmid = {28769904},
issn = {1664-302X},
abstract = {Methanogenic archaea are important for the global greenhouse gas budget since they produce methane under anoxic conditions in numerous natural environments such as oceans, estuaries, soils, and lakes. Whether and how environmental change will propagate into methanogenic assemblages of natural environments remains largely unknown owing to a poor understanding of global distribution patterns and environmental drivers of this specific group of microorganisms. In this study, we performed a meta-analysis targeting the biogeographic patterns and environmental controls of methanogenic communities using 94 public mcrA gene datasets. We show a global pattern of methanogenic archaea that is more associated with habitat filtering than with geographical dispersal. We identify salinity as the control on methanogenic community composition at global scale whereas pH and temperature are the major controls in non-saline soils and lakes. The importance of salinity for structuring methanogenic community composition is also reflected in the biogeography of methanogenic lineages and the physiological properties of methanogenic isolates. Linking methanogenic alpha-diversity with reported values of methane emission identifies estuaries as the most diverse methanogenic habitats with, however, minor contribution to the global methane budget. With salinity, temperature and pH our study identifies environmental drivers of methanogenic community composition facing drastic changes in many natural environments at the moment. However, consequences of this for the production of methane remain elusive owing to a lack of studies that combine methane production rate with community analysis.},
}
@article {pmid28765217,
year = {2017},
author = {Daume, M and Uhl, M and Backofen, R and Randau, L},
title = {RIP-Seq Suggests Translational Regulation by L7Ae in Archaea.},
journal = {mBio},
volume = {8},
number = {4},
pages = {},
pmid = {28765217},
issn = {2150-7511},
mesh = {Archaeal Proteins/*genetics/metabolism ; Escherichia coli/genetics ; *Gene Expression Regulation, Archaeal ; Immunoprecipitation ; Protein Binding ; *Protein Biosynthesis ; RNA, Archaeal/chemistry/*genetics ; RNA, Untranslated/genetics ; RNA-Binding Proteins/genetics/metabolism ; Ribosomal Proteins/genetics ; *Sequence Analysis, RNA ; Sulfolobus acidocaldarius/*genetics/metabolism ; },
abstract = {L7Ae is a universal archaeal protein that recognizes and stabilizes kink-turn (k-turn) motifs in RNA substrates. These structural motifs are widespread in nature and are found in many functional RNA species, including ribosomal RNAs. Synthetic biology approaches utilize L7Ae/k-turn interactions to control gene expression in eukaryotes. Here, we present results of comprehensive RNA immunoprecipitation sequencing (RIP-Seq) analysis of genomically tagged L7Ae from the hyperthermophilic archaeon Sulfolobus acidocaldarius A large set of interacting noncoding RNAs was identified. In addition, several mRNAs, including the l7ae transcript, were found to contain k-turn motifs that facilitate L7Ae binding. In vivo studies showed that L7Ae autoregulates the translation of its mRNA by binding to a k-turn motif present in the 5' untranslated region (UTR). A green fluorescent protein (GFP) reporter system was established in Escherichia coli and verified conservation of L7Ae-mediated feedback regulation in Archaea Mobility shift assays confirmed binding to a k-turn in the transcript of nop5-fibrillarin, suggesting that the expression of all C/D box sRNP core proteins is regulated by L7Ae. These studies revealed that L7Ae-mediated gene regulation evolved in archaeal organisms, generating new tools for the modulation of synthetic gene circuits in bacteria.IMPORTANCE L7Ae is an essential archaeal protein that is known to structure ribosomal RNAs and small RNAs (sRNAs) by binding to their kink-turn motifs. Here, we utilized RIP-Seq methodology to achieve a first global analysis of RNA substrates for L7Ae. Several novel interactions with noncoding RNA molecules (e.g., with the universal signal recognition particle RNA) were discovered. In addition, L7Ae was found to bind to mRNAs, including its own transcript's 5' untranslated region. This feedback-loop control is conserved in most archaea and was incorporated into a reporter system that was utilized to control gene expression in bacteria. These results demonstrate that L7Ae-mediated gene regulation evolved originally in archaeal organisms. The feedback-controlled reporter gene system can easily be adapted for synthetic biology approaches that require strict gene expression control.},
}
@article {pmid28765215,
year = {2017},
author = {Skennerton, CT and Chourey, K and Iyer, R and Hettich, RL and Tyson, GW and Orphan, VJ},
title = {Methane-Fueled Syntrophy through Extracellular Electron Transfer: Uncovering the Genomic Traits Conserved within Diverse Bacterial Partners of Anaerobic Methanotrophic Archaea.},
journal = {mBio},
volume = {8},
number = {4},
pages = {},
pmid = {28765215},
issn = {2150-7511},
mesh = {Anaerobiosis ; Archaea/*genetics/*metabolism ; Bacteria/*genetics/*metabolism ; Electron Transport ; Genome, Archaeal ; Genome, Bacterial ; Geologic Sediments/microbiology ; Hydrogen/metabolism ; Metagenomics ; Methane/*metabolism ; Oxidation-Reduction ; Phylogeny ; Sulfates/metabolism ; },
abstract = {The anaerobic oxidation of methane by anaerobic methanotrophic (ANME) archaea in syntrophic partnership with deltaproteobacterial sulfate-reducing bacteria (SRB) is the primary mechanism for methane removal in ocean sediments. The mechanism of their syntrophy has been the subject of much research as traditional intermediate compounds, such as hydrogen and formate, failed to decouple the partners. Recent findings have indicated the potential for extracellular electron transfer from ANME archaea to SRB, though it is unclear how extracellular electrons are integrated into the metabolism of the SRB partner. We used metagenomics to reconstruct eight genomes from the globally distributed SEEP-SRB1 clade of ANME partner bacteria to determine what genomic features are required for syntrophy. The SEEP-SRB1 genomes contain large multiheme cytochromes that were not found in previously described free-living SRB and also lack periplasmic hydrogenases that may prevent an independent lifestyle without an extracellular source of electrons from ANME archaea. Metaproteomics revealed the expression of these cytochromes at in situ methane seep sediments from three sites along the Pacific coast of the United States. Phylogenetic analysis showed that these cytochromes appear to have been horizontally transferred from metal-respiring members of the Deltaproteobacteria such as Geobacter and may allow these syntrophic SRB to accept extracellular electrons in place of other chemical/organic electron donors.IMPORTANCE Some archaea, known as anaerobic methanotrophs, are capable of converting methane into carbon dioxide when they are growing syntopically with sulfate-reducing bacteria. This partnership is the primary mechanism for methane removal in ocean sediments; however, there is still much to learn about how this syntrophy works. Previous studies have failed to identify the metabolic intermediate, such as hydrogen or formate, that is passed between partners. However, recent analysis of methanotrophic archaea has suggested that the syntrophy is formed through direct electron transfer. In this research, we analyzed the genomes of multiple partner bacteria and showed that they also contain the genes necessary to perform extracellular electron transfer, which are absent in related bacteria that do not form syntrophic partnerships with anaerobic methanotrophs. This genomic evidence shows a possible mechanism for direct electron transfer from methanotrophic archaea into the metabolism of the partner bacteria.},
}
@article {pmid28755506,
year = {2017},
author = {Di Maiuta, N and Rüfenacht, A and Küenzi, P},
title = {Assessment of bacteria and archaea in metalworking fluids using massive parallel 16S rRNA gene tag sequencing.},
journal = {Letters in applied microbiology},
volume = {65},
number = {4},
pages = {266-273},
doi = {10.1111/lam.12782},
pmid = {28755506},
issn = {1472-765X},
mesh = {Azides/chemistry ; Disinfectants ; Fungi/*classification/genetics/isolation &amp; purification ; High-Throughput Nucleotide Sequencing ; Manufacturing and Industrial Facilities ; Methanobrevibacter/*classification/genetics/isolation &amp; purification ; Propidium/analogs &amp; derivatives/chemistry ; Pseudomonas/*classification/genetics/isolation &amp; purification ; RNA, Ribosomal, 16S/genetics ; },
abstract = {Determination of the bacterial diversity in industry-based liquid in-use water-miscible metalworking fluid (MWF) samples was targeted by massive parallel multiplex DNA sequencing, either directly or upon pretreatment with propidium monoazide (PMA) that allows differentiation between intact and physically damaged cells. As MWFs provide a suitable basis of life for micro-organisms, the majority is preserved by biocides. 'Bio-concept' fluids on the other hand are bactericide free, which intentionally leads to substantial bacterial populations. Samples from both fluid types were chosen: A median of 51 operational taxonomic units at genera level (OTUs) were detected per sample, but only 13 were present at or above 1·0% of the total population in any PMA-treated sample analysed. As both fluid types were mainly dominated by Pseudomonas spp., we resolved this genus on the species level and found the Pseudomonas oleovorans/pseudoalcaligenes group to predominate. We also looked for archaea and detected Methanobrevibacter spp., albeit in <3% of all samples analysed.<br><br>Water-miscible metalworking fluids provide a suitable base of life for micro-organisms, mainly bacteria and fungi. Earlier publications suggested that the diversity is rather low, but these studies were largely based on heterotrophic plate counts. This might have resulted in underestimation of population density and microbial diversity as some organisms might just refuse to grow. This study used high-throughput sequencing in the absence and presence of propidium monoazide to explore bacterial and archaeal presence in metalworking fluids. We established that diversity is low and bacterial populations are dominated by the genus Pseudomonas spp.},
}
@article {pmid28741608,
year = {2017},
author = {Spang, A and Ettema, TJG},
title = {Archaeal evolution: The methanogenic roots of Archaea.},
journal = {Nature microbiology},
volume = {2},
number = {},
pages = {17109},
pmid = {28741608},
issn = {2058-5276},
mesh = {Archaea/*genetics ; Chemoautotrophic Growth ; DNA, Archaeal ; *Euryarchaeota ; },
}
@article {pmid28734066,
year = {2017},
author = {Varnava, KG and Ronimus, RS and Sarojini, V},
title = {A review on comparative mechanistic studies of antimicrobial peptides against archaea.},
journal = {Biotechnology and bioengineering},
volume = {114},
number = {11},
pages = {2457-2473},
doi = {10.1002/bit.26387},
pmid = {28734066},
issn = {1097-0290},
mesh = {Antimicrobial Cationic Peptides/*administration &amp; dosage ; Apoptosis/*drug effects/*physiology ; Archaea/cytology/*drug effects/*physiology ; Cell Survival/drug effects/physiology ; Dose-Response Relationship, Drug ; Microbial Sensitivity Tests/*methods ; Species Specificity ; },
abstract = {Archaea was until recently considered as a third domain of life in addition to bacteria and eukarya but recent studies support the existence of only two superphyla (bacteria and archaea). The fundamental differences between archaeal, bacterial, and eukaryal cells are probably the main reasons for the comparatively lower susceptibility of archaeal strains to current antimicrobial agents. The possible emerging pathogenicity of archaea and the role of archaeal methanogens in methane emissions, a potent greenhouse gas, has led many researchers to examine the sensitivity patterns of archaea and make attempts to find agents that have significant anti-archaeal activity. Even though antimicrobial peptides (AMPs) are well known with several published reviews concerning their mode of action against bacteria and eukarya, to our knowledge, to date no reviews are available that focus on the action of these peptides against archaea. Herein, we present a review on all the peptides that have been tested against archaea. In addition, in an attempt to shed more light on possible future work that needs to be performed we have included a brief overview of the chemical characteristics, spectrum of activity, and the known mechanism of action of each of these peptides against bacteria and/or fungi. We also discuss the nature of and key physiological differences between Archaea, Bacteria, and Eukarya that are relevant to the development of anti-archaeal peptides. Despite our relatively limited knowledge about archaea, available data suggest that AMPs have an even broader spectrum of activity than currently recognized.},
}
@article {pmid28713363,
year = {2017},
author = {Jing, H and Cheung, S and Xia, X and Suzuki, K and Nishioka, J and Liu, H},
title = {Geographic Distribution of Ammonia-Oxidizing Archaea along the Kuril Islands in the Western Subarctic Pacific.},
journal = {Frontiers in microbiology},
volume = {8},
number = {},
pages = {1247},
pmid = {28713363},
issn = {1664-302X},
abstract = {Community composition and abundance of ammonia-oxidizing archaea (AOA) in the ocean were affected by different physicochemical conditions, but their responses to physical barriers (such as a chain of islands) were largely unknown. In our study, geographic distribution of the AOA from the surface photic zone to the deep bathypelagic waters in the western subarctic Pacific adjacent to the Kuril Islands was investigated using pyrosequencing based on the ammonia monooxygenase subunit A (amoA) gene. Genotypes of clusters A and B dominated in the upper euphotic zone and the deep waters, respectively. Quantitative PCR assays revealed that the occurrence and ammonia-oxidizing activity of ammonia-oxidizing archaea (AOA) reached their maxima at the depth of 200 m, where a higher diversity and abundance of actively transcribed AOA was observed at the station located in the marginal sea exposed to more terrestrial input. Similar community composition of AOA observed at the two stations adjacent to the Kuril Islands maybe due to water exchange across the Bussol Strait. They distinct from the station located in the western subarctic gyre, where sub-cluster WCAII had a specific distribution in the surface water, and this sub-cluster seemed having a confined distribution in the western Pacific. Habitat-specific groupings of different WCB sub-clusters were observed reflecting the isolated microevolution existed in cluster WCB. The effect of the Kuril Islands on the phylogenetic composition of AOA between the Sea of Okhotsk and the western subarctic Pacific is not obvious, possibly because our sampling stations are near to the Bussol Strait, the main gateway through which water is exchanged between the Sea of Okhotsk and the Pacific. The vertical and horizontal distribution patterns of AOA communities among stations along the Kuril Islands were essentially determined by the in situ prevailing physicochemical gradients along the two dimensions.},
}
@article {pmid28710268,
year = {2017},
author = {Duszenko, N and Buan, NR},
title = {Physiological Evidence for Isopotential Tunneling in the Electron Transport Chain of Methane-Producing Archaea.},
journal = {Applied and environmental microbiology},
volume = {83},
number = {18},
pages = {},
pmid = {28710268},
issn = {1098-5336},
support = {P20 GM113126/GM/NIGMS NIH HHS/United States ; P20 RR017675/RR/NCRR NIH HHS/United States ; },
mesh = {Benzoquinones/metabolism ; Electron Transport ; Escherichia coli/genetics/growth &amp; development/metabolism ; Hydrogen/metabolism ; Methane/*metabolism ; Methanosarcina/genetics/growth &amp; development/*metabolism ; },
abstract = {Many, but not all, organisms use quinones to conserve energy in their electron transport chains. Fermentative bacteria and methane-producing archaea (methanogens) do not produce quinones but have devised other ways to generate ATP. Methanophenazine (MPh) is a unique membrane electron carrier found in Methanosarcina species that plays the same role as quinones in the electron transport chain. To extend the analogy between quinones and MPh, we compared the MPh pool sizes between two well-studied Methanosarcina species, Methanosarcina acetivorans C2A and Methanosarcina barkeri Fusaro, to the quinone pool size in the bacterium Escherichia coli We found the quantity of MPh per cell increases as cultures transition from exponential growth to stationary phase, and absolute quantities of MPh were 3-fold higher in M. acetivorans than in M. barkeri The concentration of MPh suggests the cell membrane of M. acetivorans, but not of M. barkeri, is electrically quantized as if it were a single conductive metal sheet and near optimal for rate of electron transport. Similarly, stationary (but not exponentially growing) E. coli cells also have electrically quantized membranes on the basis of quinone content. Consistent with our hypothesis, we demonstrated that the exogenous addition of phenazine increases the growth rate of M. barkeri three times that of M. acetivorans Our work suggests electron flux through MPh is naturally higher in M. acetivorans than in M. barkeri and that hydrogen cycling is less efficient at conserving energy than scalar proton translocation using MPh.IMPORTANCE Can we grow more from less? The ability to optimize and manipulate metabolic efficiency in cells is the difference between commercially viable and nonviable renewable technologies. Much can be learned from methane-producing archaea (methanogens) which evolved a successful metabolic lifestyle under extreme thermodynamic constraints. Methanogens use highly efficient electron transport systems and supramolecular complexes to optimize electron and carbon flow to control biomass synthesis and the production of methane. Worldwide, methanogens are used to generate renewable methane for heat, electricity, and transportation. Our observations suggest Methanosarcina acetivorans, but not Methanosarcina barkeri, has electrically quantized membranes. Escherichia coli, a model facultative anaerobe, has optimal electron transport at the stationary phase but not during exponential growth. This study also suggests the metabolic efficiency of bacteria and archaea can be improved using exogenously supplied lipophilic electron carriers. The enhancement of methanogen electron transport through methanophenazine has the potential to increase renewable methane production at an industrial scale.},
}
@article {pmid28681113,
year = {2017},
author = {Sheppard, C and Werner, F},
title = {Structure and mechanisms of viral transcription factors in archaea.},
journal = {Extremophiles : life under extreme conditions},
volume = {21},
number = {5},
pages = {829-838},
pmid = {28681113},
issn = {1433-4909},
mesh = {Archaeal Viruses/*genetics/metabolism ; Gene Expression Regulation, Viral ; Transcription Factors/chemistry/genetics/*metabolism ; Viral Proteins/chemistry/genetics/*metabolism ; },
abstract = {Virus-encoded transcription factors have been pivotal in exploring the molecular mechanisms and regulation of gene expression in bacteria and eukaryotes since the birth of molecular biology, while our understanding of viral transcription in archaea is still in its infancy. Archaeal viruses do not encode their own RNA polymerases (RNAPs) and are consequently entirely dependent on their hosts for gene expression; this is fundamentally different from many bacteriophages and requires alternative regulatory strategies. Archaeal viruses wield a repertoire of proteins to expropriate the host transcription machinery to their own benefit. In this short review we summarise our current understanding of gene-specific and global mechanisms that viruses employ to chiefly downregulate host transcription and enable the efficient and temporal expression of the viral transcriptome. Most of the experimentally characterised archaeo-viral transcription regulators possess either ribbon-helix-helix or Zn-finger motifs that allow them to engage with the DNA in a sequence-specific manner, altering the expression of a specific subset of genes. Recently a novel type of regulator was reported that directly binds to the RNAP and shuts down transcription of both host and viral genes in a global fashion.},
}
@article {pmid28680072,
year = {2017},
author = {Golyshina, OV and Toshchakov, SV and Makarova, KS and Gavrilov, SN and Korzhenkov, AA and La Cono, V and Arcadi, E and Nechitaylo, TY and Ferrer, M and Kublanov, IV and Wolf, YI and Yakimov, MM and Golyshin, PN},
title = {'ARMAN' archaea depend on association with euryarchaeal host in culture and in situ.},
journal = {Nature communications},
volume = {8},
number = {1},
pages = {60},
pmid = {28680072},
issn = {2041-1723},
support = {/ImNIH/Intramural NIH HHS/United States ; },
mesh = {Archaea/*classification/genetics/*physiology ; Gene Expression Regulation, Archaeal ; Genetic Variation ; Genome, Archaeal ; Microscopy, Fluorescence ; Phylogeny ; RNA, Archaeal/genetics ; RNA, Ribosomal, 16S/genetics ; Species Specificity ; },
abstract = {Intriguing, yet uncultured 'ARMAN'-like archaea are metabolically dependent on other members of the microbial community. It remains uncertain though which hosts they rely upon, and, because of the lack of complete genomes, to what extent. Here, we report the co-culturing of ARMAN-2-related organism, Mia14, with Cuniculiplasma divulgatum PM4 during the isolation of this strain from acidic streamer in Parys Mountain (Isle of Anglesey, UK). Mia14 is highly enriched in the binary culture (ca. 10% genomic reads) and its ungapped 0.95 Mbp genome points at severe voids in central metabolic pathways, indicating dependence on the host, C. divulgatum PM4. Analysis of C. divulgatum isolates from different sites and shotgun sequence data of Parys Mountain samples suggests an extensive genetic exchange between Mia14 and hosts in situ. Within the subset of organisms with high-quality genomic assemblies representing the 'DPANN' superphylum, the Mia14 lineage has had the largest gene flux, with dozens of genes gained that are implicated in the host interaction.In the absence of complete genomes, the metabolic capabilities of uncultured ARMAN-like archaea have been uncertain. Here, Golyshina et al. apply an enrichment culture technique and find that the ungapped genome of the ARMAN-like archaeon Mia14 has lost key metabolic pathways, suggesting dependence on the host archaeon Cuniculiplasma divulgatum.},
}
@article {pmid28677304,
year = {2017},
author = {Tolar, BB and Herrmann, J and Bargar, JR and van den Bedem, H and Wakatsuki, S and Francis, CA},
title = {Integrated structural biology and molecular ecology of N-cycling enzymes from ammonia-oxidizing archaea.},
journal = {Environmental microbiology reports},
volume = {9},
number = {5},
pages = {484-491},
doi = {10.1111/1758-2229.12567},
pmid = {28677304},
issn = {1758-2229},
mesh = {Ammonia/*metabolism ; Archaea/classification/enzymology/*genetics/*metabolism ; Enzymes/*chemistry/*metabolism ; Nitrite Reductases/chemistry/genetics/metabolism ; *Oxidation-Reduction ; Oxidoreductases/chemistry/genetics/metabolism ; Phylogeny ; Structure-Activity Relationship ; },
abstract = {Knowledge of the molecular ecology and environmental determinants of ammonia-oxidizing organisms is critical to understanding and predicting the global nitrogen (N) and carbon cycles, but an incomplete biochemical picture hinders in vitro studies of N-cycling enzymes. Although an integrative structural and dynamic characterization at the atomic scale would advance our understanding of function tremendously, structural knowledge of key N-cycling enzymes from ecologically relevant ammonia oxidizers is unfortunately extremely limited. Here, we discuss the challenges and opportunities for examining the ecology of ammonia-oxidizing organisms, particularly uncultivated Thaumarchaeota, through (meta)genome-driven structural biology of the enzymes ammonia monooxygenase (AMO) and nitrite reductase (NirK).},
}
@article {pmid28663746,
year = {2017},
author = {Liu, H and Zhang, CL and Yang, C and Chen, S and Cao, Z and Zhang, Z and Tian, J},
title = {Marine Group II Dominates Planktonic Archaea in Water Column of the Northeastern South China Sea.},
journal = {Frontiers in microbiology},
volume = {8},
number = {},
pages = {1098},
pmid = {28663746},
issn = {1664-302X},
abstract = {Temperature, nutrients, and salinity are among the important factors constraining the distribution and abundance of microorganisms in the ocean. Marine Group II (MGII) belonging to Euryarchaeota commonly dominates the planktonic archaeal community in shallow water and Marine Group I (MGI, now is called Thaumarchaeota) in deeper water in global oceans. Results of quantitative PCR (qPCR) and 454 sequencing in our study, however, showed the dominance of MGII in planktonic archaea throughout the water column of the northeastern South China Sea (SCS) that is characterized by strong water mixing. The abundance of ammonia-oxidizing archaea (AOA) representing the main group of Thaumarchaeota in deeper water in the northeastern SCS was significantly lower than in other oceanic regions. Phylogenetic analysis showed that the top operational taxonomic units (OTUs) of the MGII occurring predominantly below 200 m depth may be unique in the northeastern SCS based on the observation that they are distantly related to known sequences (identity ranging from 90-94%). The abundance of MGII was also significantly correlated with total bacteria in the whole column, which may indicate that MGII and bacteria may have similar physiological or biochemical properties or responses to environmental variation. This study provides valuable information about the dominance of MGII over AOA in both shallow and deep water in the northeastern SCS and highlights the need for comprehensive studies integrating physical, chemical, and microbial oceanography.},
}
@article {pmid28659382,
year = {2017},
author = {Staley, JT},
title = {Domain Cell Theory supports the independent evolution of the Eukarya, Bacteria and Archaea and the Nuclear Compartment Commonality hypothesis.},
journal = {Open biology},
volume = {7},
number = {6},
pages = {},
pmid = {28659382},
issn = {2046-2441},
mesh = {Archaea/*classification/cytology ; Bacteria/*classification/cytology ; *Biological Evolution ; *Cell Nucleus ; Eukaryota/*classification/cytology ; *Models, Theoretical ; Phylogeny ; },
abstract = {In 2015, the Royal Society of London held a meeting to discuss the various hypotheses regarding the origin of the Eukarya. Although not all participants supported a hypothesis, the proposals that did fit into two broad categories: one group favoured 'Prokaryotes First' hypotheses and another addressed 'Eukaryotes First' hypotheses. Those who proposed Prokaryotes First hypotheses advocated either a fusion event between a bacterium and an archaeon that produced the first eukaryote or the direct evolution of the Eukarya from the Archaea. The Eukaryotes First proponents posit that the eukaryotes evolved initially and then, by reductive evolution, produced the Bacteria and Archaea. No mention was made of another previously published hypothesis termed the Nuclear Compartment Commonality (NuCom) hypothesis, which proposed the evolution of the Eukarya and Bacteria from nucleated ancestors (Staley 2013 Astrobiol Outreach1, 105 (doi:10.4172/2332-2519.1000105)). Evidence from two studies indicates that the nucleated Planctomycetes-Verrucomicrobia-Chlamydia superphylum members are the most ancient Bacteria known (Brochier &amp; Philippe 2002 Nature417, 244 (doi:10.1038/417244a); Jun et al. 2010 Proc. Natl Acad. Sci. USA107, 133-138 (doi:10.1073/pnas.0913033107)). This review summarizes the evidence for the NuCom hypothesis and discusses how simple the NuCom hypothesis is in explaining eukaryote evolution relative to the other hypotheses. The philosophical importance of simplicity and its relationship to truth in hypotheses such as NuCom and Domain Cell Theory is presented. Domain Cell Theory is also proposed herein, which contends that each of the three cellular lineages of life, the Archaea, Bacteria and Eukarya domains, evolved independently, in support of the NuCom hypothesis. All other proposed hypotheses violate Domain Cell Theory because they posit the evolution of different cellular descendants from ancestral cellular types.},
}
@article {pmid28657885,
year = {2017},
author = {Koonin, EV and Makarova, KS and Wolf, YI},
title = {Evolutionary Genomics of Defense Systems in Archaea and Bacteria.},
journal = {Annual review of microbiology},
volume = {71},
number = {},
pages = {233-261},
pmid = {28657885},
issn = {1545-3251},
support = {Z01 LM000061-15//NULL/International ; Z01 LM000073-12//NULL/International ; },
mesh = {Archaea/*genetics/*virology ; Bacteria/*genetics/*virology ; CRISPR-Cas Systems ; DNA Restriction-Modification Enzymes ; *Evolution, Molecular ; Genome, Archaeal ; Genome, Bacterial ; Genomics ; *Host-Parasite Interactions ; },
abstract = {Evolution of bacteria and archaea involves an incessant arms race against an enormous diversity of genetic parasites. Accordingly, a substantial fraction of the genes in most bacteria and archaea are dedicated to antiparasite defense. The functions of these defense systems follow several distinct strategies, including innate immunity; adaptive immunity; and dormancy induction, or programmed cell death. Recent comparative genomic studies taking advantage of the expanding database of microbial genomes and metagenomes, combined with direct experiments, resulted in the discovery of several previously unknown defense systems, including innate immunity centered on Argonaute proteins, bacteriophage exclusion, and new types of CRISPR-Cas systems of adaptive immunity. Some general principles of function and evolution of defense systems are starting to crystallize, in particular, extensive gain and loss of defense genes during the evolution of prokaryotes; formation of genomic defense islands; evolutionary connections between mobile genetic elements and defense, whereby genes of mobile elements are repeatedly recruited for defense functions; the partially selfish and addictive behavior of the defense systems; and coupling between immunity and dormancy induction/programmed cell death.},
}
@article {pmid28655184,
year = {2017},
author = {Cranford, MT and Chu, AM and Baguley, JK and Bauer, RJ and Trakselis, MA},
title = {Characterization of a coupled DNA replication and translesion synthesis polymerase supraholoenzyme from archaea.},
journal = {Nucleic acids research},
volume = {45},
number = {14},
pages = {8329-8340},
pmid = {28655184},
issn = {1362-4962},
mesh = {Archaeal Proteins/chemistry/genetics/*metabolism ; Blotting, Western ; *DNA Repair ; *DNA Replication ; DNA, Archaeal/chemistry/genetics/metabolism ; DNA-Directed DNA Polymerase/chemistry/genetics/*metabolism ; Holoenzymes/chemistry/genetics/metabolism ; Kinetics ; Models, Molecular ; Nucleic Acid Conformation ; Proliferating Cell Nuclear Antigen/genetics/metabolism ; Protein Binding ; Protein Structure, Tertiary ; Spectrometry, Fluorescence ; Sulfolobus solfataricus/enzymology/genetics/metabolism ; },
abstract = {The ability of the replisome to seamlessly coordinate both high fidelity and translesion DNA synthesis requires a means to regulate recruitment and binding of enzymes from solution. Co-occupancy of multiple DNA polymerases within the replisome has been observed primarily in bacteria and is regulated by posttranslational modifications in eukaryotes, and both cases are coordinated by the processivity clamp. Because of the heterotrimeric nature of the PCNA clamp in some archaea, there is potential to occupy and regulate specific polymerases at defined subunits. In addition to specific PCNA and polymerase interactions (PIP site), we have now identified and characterized a novel protein contact between the Y-family DNA polymerase and the B-family replication polymerase (YB site) bound to PCNA and DNA from Sulfolobus solfataricus. These YB contacts are essential in forming and stabilizing a supraholoenzyme (SHE) complex on DNA, effectively increasing processivity of DNA synthesis. The SHE complex can not only coordinate polymerase exchange within the complex but also provides a mechanism for recruitment of polymerases from solution based on multiequilibrium processes. Our results provide evidence for an archaeal PCNA 'tool-belt' recruitment model of multienzyme function that can facilitate both high fidelity and translesion synthesis within the replisome during DNA replication.},
}
@article {pmid28647121,
year = {2017},
author = {Xu, J and Jia, Z and Lin, X and Feng, Y},
title = {DNA-based stable isotope probing identifies formate-metabolizing methanogenic archaea in paddy soil.},
journal = {Microbiological research},
volume = {202},
number = {},
pages = {36-42},
doi = {10.1016/j.micres.2017.05.004},
pmid = {28647121},
issn = {1618-0623},
mesh = {*Biodegradation, Environmental ; Carbon Isotopes ; China ; Cloning, Molecular ; DNA/chemistry ; *DNA Probes ; DNA, Archaeal ; Denaturing Gradient Gel Electrophoresis ; Euryarchaeota/classification/*genetics/*metabolism ; Formates/*metabolism ; Methane/biosynthesis ; Phylogeny ; RNA, Ribosomal, 16S/genetics ; Real-Time Polymerase Chain Reaction ; Soil ; Soil Microbiology ; },
abstract = {Paddy methane (CH4) production is biologically dominated by methanogenic archaea that metabolize a variety of organic and/or inorganic carbon sources. Though formate is easily dissimilated into H2/CO2, formate-metabolizing methanogenic archaea are distinct from CO2-utilizing methanogen taxa. The identity of formate-metabolizing methanogenic archaea in paddy soil remains elusive. In this investigation, molecular approaches based on stable isotope probing (SIP) technique were conducted to identify the formate-metabolizing methanogenic archaea in paddy soil. CH4 emission monitor, real-time quantitative PCR (qPCR) and Denaturing Gradient Gel Electrophoresis (DGGE) analyses consistently indicated that some methanogenic archaea metabolized 13C-labeled formate in microcosm and accounted for a large portion of formate-metabolizing archaea in anoxic paddy soil. Phylogenetic identification further found that this guild was affiliated to Methanobacteriaceae. Taken together Methanobacteriaceae could be the dominant formate-metabolizing methanogenic archaea and play an important role in the CH4 production in paddy soil. These findings would extend the extant knowledge on paddy methanogenic archaea and microbial-driven paddy CH4 emission.},
}
@article {pmid28642547,
year = {2017},
author = {Moissl-Eichinger, C and Probst, AJ and Birarda, G and Auerbach, A and Koskinen, K and Wolf, P and Holman, HN},
title = {Human age and skin physiology shape diversity and abundance of Archaea on skin.},
journal = {Scientific reports},
volume = {7},
number = {1},
pages = {4039},
pmid = {28642547},
issn = {2045-2322},
mesh = {Age Factors ; Archaea/*classification/*genetics ; Biodiversity ; Female ; High-Throughput Nucleotide Sequencing ; Humans ; Male ; *Microbiota ; Middle Aged ; Phylogeny ; RNA, Ribosomal, 16S ; Skin/*microbiology ; *Skin Physiological Phenomena ; Spectroscopy, Fourier Transform Infrared ; },
abstract = {The human skin microbiome acts as an important barrier protecting our body from pathogens and other environmental influences. Recent investigations have provided evidence that Archaea are a constant but highly variable component of the human skin microbiome, yet factors that determine their abundance changes are unknown. Here, we tested the hypothesis that the abundance of archaea on human skin is influenced by human age and skin physiology by quantitative PCR of 51 different skin samples taken from human subjects of various age. Our results reveal that archaea are more abundant in human subjects either older than 60 years or younger than 12 years as compared to middle-aged human subjects. These results, together with results obtained from spectroscopy analysis, allowed us gain first insights into a potential link of lower sebum levels and lipid content and thus reduced skin moisture with an increase in archaeal signatures. Amplicon sequencing of selected samples revealed the prevalence of specific eury- and mainly thaumarchaeal taxa, represented by a core archaeome of the human skin.},
}
@article {pmid28628615,
year = {2017},
author = {Cossu, M and Badel, C and Catchpole, R and Gadelle, D and Marguet, E and Barbe, V and Forterre, P and Oberto, J},
title = {Flipping chromosomes in deep-sea archaea.},
journal = {PLoS genetics},
volume = {13},
number = {6},
pages = {e1006847},
pmid = {28628615},
issn = {1553-7404},
mesh = {Chromosome Inversion/*genetics ; *Evolution, Molecular ; Genome, Archaeal ; Integrases/*genetics ; Interspersed Repetitive Sequences/genetics ; Plasmids/genetics ; Recombination, Genetic ; Thermococcales/*genetics ; },
abstract = {One of the major mechanisms driving the evolution of all organisms is genomic rearrangement. In hyperthermophilic Archaea of the order Thermococcales, large chromosomal inversions occur so frequently that even closely related genomes are difficult to align. Clearly not resulting from the native homologous recombination machinery, the causative agent of these inversions has remained elusive. We present a model in which genomic inversions are catalyzed by the integrase enzyme encoded by a family of mobile genetic elements. We characterized the integrase from Thermococcus nautili plasmid pTN3 and showed that besides canonical site-specific reactions, it catalyzes low sequence specificity recombination reactions with the same outcome as homologous recombination events on DNA segments as short as 104bp both in vitro and in vivo, in contrast to other known tyrosine recombinases. Through serial culturing, we showed that the integrase-mediated divergence of T. nautili strains occurs at an astonishing rate, with at least four large-scale genomic inversions appearing within 60 generations. Our results and the ubiquitous distribution of pTN3-like integrated elements suggest that a major mechanism of evolution of an entire order of Archaea results from the activity of a selfish mobile genetic element.},
}
@article {pmid28628315,
year = {2017},
author = {Dokainish, HM and Simard, DJ and Gauld, JW},
title = {A Pseudohypervalent Sulfur Intermediate as an Oxidative Protective Mechanism in the Archaea Peroxiredoxin Enzyme ApTPx.},
journal = {The journal of physical chemistry. B},
volume = {121},
number = {27},
pages = {6570-6579},
doi = {10.1021/acs.jpcb.7b04671},
pmid = {28628315},
issn = {1520-5207},
mesh = {Archaea/*enzymology ; Molecular Dynamics Simulation ; Oxidation-Reduction ; Peroxiredoxins/chemistry/*metabolism ; *Quantum Theory ; Sulfur/chemistry/*metabolism ; },
abstract = {Peroxiredoxins (Prxs) are a ubiquitous class of enzymes that have central roles in a number of important physiological processes. Using a multiscale computational approach, we have investigated the mechanism by which the active-site cysteine (Cys50) in the typical 2-Cys Prx from Archaea (ApTPx) is oxidized by H2O2 to sulfenic acid. In addition, its further oxidation to give a sulfinic acid and its possible alternate intramolecular reaction to form an experimentally proposed hypervalent sulfurane were examined. Oxidation of Cys50 by H2O2 to give the sulfenic acid intermediate occurs in one step with a barrier of 82.1 kJ mol-1. A two-step pathway is proposed with a very low barrier of 16.5 kJ mol-1 by which it can subsequently react with an adjacent histidyl (His42) to form the pseudohypervalent sulfurane. This pathway also involves an adjacent aspartyl (Asp45), which helps alternate the protonation state of His42. The sulfurane's Cys50S···NδHis42 interaction was characterized using QTAIM, NCI, and NBO analyses and found to be a noncovalent interaction. Notably, this bond helps orient the Cys50SOH moiety such that it is less susceptible to oxidation by H2O2 to sulfinic acid. Significantly, sulfurane formation is energetically favored to further H2O2 oxidation of Cys50SOH to a sulfinic acid, providing a mechanism by which the active-site Cys50 is protected against overoxidation.},
}
@article {pmid28625421,
year = {2017},
author = {Gaglione, R and Pirone, L and Farina, B and Fusco, S and Smaldone, G and Aulitto, M and Dell'Olmo, E and Roscetto, E and Del Gatto, A and Fattorusso, R and Notomista, E and Zaccaro, L and Arciello, A and Pedone, E and Contursi, P},
title = {Insights into the anticancer properties of the first antimicrobial peptide from Archaea.},
journal = {Biochimica et biophysica acta. General subjects},
volume = {1861},
number = {9},
pages = {2155-2164},
doi = {10.1016/j.bbagen.2017.06.009},
pmid = {28625421},
issn = {0304-4165},
mesh = {Animals ; Antimicrobial Cationic Peptides/chemistry/*pharmacology ; Antineoplastic Agents/chemistry/*pharmacology ; BALB 3T3 Cells ; Cell Death/drug effects ; Cell Membrane/drug effects ; Circular Dichroism ; Humans ; Mice ; Nuclear Magnetic Resonance, Biomolecular ; Protein Conformation ; Sulfolobus/*chemistry ; },
abstract = {BACKGROUND: The peptide VLL-28, identified in the sequence of an archaeal protein, the transcription factor Stf76 from Sulfolobus islandicus, was previously identified and characterized as an antimicrobial peptide, possessing a broad-spectrum antibacterial activity.<br><br>METHODS: Through a combined approach of NMR and Circular Dichroism spectroscopy, Dynamic Light Scattering, confocal microscopy and cell viability assays, the interaction of VLL-28 with the membranes of both parental and malignant cell lines has been characterized and peptide mechanism of action has been studied.<br><br>RESULTS: It is here demonstrated that VLL-28 selectively exerts cytotoxic activity against murine and human tumor cells. By means of structural methodologies, VLL-28 interaction with the membranes has been proven and the binding residues have been identified. Confocal microscopy data show that VLL-28 is internalized only into tumor cells. Finally, it is shown that cell death is mainly caused by a time-dependent activation of apoptotic pathways.<br><br>CONCLUSIONS: VLL-28, deriving from the archaeal kingdom, is here found to be endowed with selective cytotoxic activity towards both murine and human cancer cells and consequently can be classified as an ACP.<br><br>GENERAL SIGNIFICANCE: VLL-28 represents the first ACP identified in an archaeal microorganism, exerting a trans-kingdom activity.},
}
@article {pmid28587211,
year = {2017},
author = {Karayanni, H and Meziti, A and Spatharis, S and Genitsaris, S and Courties, C and Kormas, KA},
title = {Changes in Microbial (Bacteria and Archaea) Plankton Community Structure after Artificial Dispersal in Grazer-Free Microcosms.},
journal = {Microorganisms},
volume = {5},
number = {2},
pages = {},
pmid = {28587211},
issn = {2076-2607},
abstract = {Microbes are considered to have a global distribution due to their high dispersal capabilities. However, our knowledge of the way geographically distant microbial communities assemble after dispersal in a new environment is limited. In this study, we examined whether communities would converge because similar taxa would be selected under the same environmental conditions, or would diverge because of initial community composition, after artificial dispersal. To this aim, a microcosm experiment was performed, in which the temporal changes in the composition and diversity of different prokaryoplankton assemblages from three distant geographic coastal areas (Banyuls-sur-Mer in northwest Mediterranean Sea, Pagasitikos Gulf in northeast Mediterranean and Woods Hole, MA, USA in the northwest Atlantic), were studied. Diversity was investigated using amplicon pyrosequencing of the V1-V3 hypervariable regions of the 16S rRNA. The three assemblages were grown separately in particle free and autoclaved Banyuls-sur-mer seawater at 18 °C in the dark. We found that the variability of prokaryoplankton community diversity (expressed as richness, evenness and dominance) as well as the composition were driven by patterns observed in Bacteria. Regarding community composition, similarities were found between treatments at family level. However, at the OTU level microbial communities from the three different original locations diverge rather than converge during incubation. It is suggested that slight differences in the composition of the initial prokaryoplankton communities, resulted in separate clusters the following days even when growth took place under identical abiotic conditions.},
}
@article {pmid28585938,
year = {2017},
author = {Borrel, G and McCann, A and Deane, J and Neto, MC and Lynch, DB and Brugère, JF and O'Toole, PW},
title = {Genomics and metagenomics of trimethylamine-utilizing Archaea in the human gut microbiome.},
journal = {The ISME journal},
volume = {11},
number = {9},
pages = {2059-2074},
pmid = {28585938},
issn = {1751-7370},
mesh = {Aged ; Aged, 80 and over ; Animals ; Archaea/classification/*genetics/isolation &amp; purification/*metabolism ; Feces/microbiology ; Female ; *Gastrointestinal Microbiome ; Gastrointestinal Tract/microbiology ; Genomics ; Humans ; Male ; Metagenome ; Metagenomics ; Methylamines/*metabolism ; Microbiota ; Phylogeny ; },
abstract = {The biological significance of Archaea in the human gut microbiota is largely unclear. We recently reported genomic and biochemical analyses of the Methanomassiliicoccales, a novel order of methanogenic Archaea dwelling in soil and the animal digestive tract. We now show that these Methanomassiliicoccales are present in published microbiome data sets from eight countries. They are represented by five Operational Taxonomic Units present in at least four cohorts and phylogenetically distributed into two clades. Genes for utilizing trimethylamine (TMA), a bacterial precursor to an atherosclerogenic human metabolite, were present in four of the six novel Methanomassiliicoccales genomes assembled from ELDERMET metagenomes. In addition to increased microbiota TMA production capacity in long-term residential care subjects, abundance of TMA-utilizing Methanomassiliicoccales correlated positively with bacterial gene count for TMA production and negatively with fecal TMA concentrations. The two large Methanomassiliicoccales clades have opposite correlations with host health status in the ELDERMET cohort and putative distinct genomic signatures for gut adaptation.},
}
@article {pmid28570690,
year = {2017},
author = {Majhi, MC and Behera, AK and Kulshreshtha, NM and Mahmooduzafar, D and Kumar, R and Kumar, A},
title = {Correction: ExtremeDB: A Unified Web Repository of Extremophilic Archaea and Bacteria.},
journal = {PloS one},
volume = {12},
number = {6},
pages = {e0179119},
pmid = {28570690},
issn = {1932-6203},
abstract = {[This corrects the article DOI: 10.1371/journal.pone.0063083.].},
}
@article {pmid28546547,
year = {2017},
author = {Chen, X and Andersen, TJ and Morono, Y and Inagaki, F and Jørgensen, BB and Lever, MA},
title = {Bioturbation as a key driver behind the dominance of Bacteria over Archaea in near-surface sediment.},
journal = {Scientific reports},
volume = {7},
number = {1},
pages = {2400},
pmid = {28546547},
issn = {2045-2322},
mesh = {Archaea/*classification ; Bacteria/*classification ; *Biodiversity ; DNA, Archaeal ; DNA, Bacterial ; Geologic Sediments/*microbiology ; Phylogeny ; Phylogeography ; RNA, Ribosomal, 16S/genetics ; },
abstract = {The factors controlling the relative abundances of Archaea and Bacteria in marine sediments are poorly understood. We determined depth distributions of archaeal and bacterial 16S rRNA genes by quantitative PCR at eight stations in Aarhus Bay, Denmark. Bacterial outnumber archaeal genes 10-60-fold in uppermost sediments that are irrigated and mixed by macrofauna. This bioturbation is indicated by visual observations of sediment color and faunal tracks, by porewater profiles of dissolved inorganic carbon and sulfate, and by distributions of unsupported 210Pb and 137Cs. Below the depth of bioturbation, the relative abundances of archaeal genes increase, accounting for one third of 16S rRNA genes in the sulfate zone, and half of 16S rRNA genes in the sulfate-methane transition zone and methane zone. Phylogenetic analyses reveal a strong shift in bacterial and archaeal community structure from bioturbated sediments to underlying layers. Stable isotopic analyses on organic matter and porewater geochemical gradients suggest that macrofauna mediate bacterial dominance and affect microbial community structure in bioturbated sediment by introducing fresh organic matter and high-energy electron acceptors from overlying seawater. Below the zone of bioturbation, organic matter content and the presence of sulfate exert key influences on bacterial and archaeal abundances and overall microbial community structure.},
}
@article {pmid28523826,
year = {2017},
author = {Zheng, L and Zhao, X and Zhu, G and Yang, W and Xia, C and Xu, T},
title = {Occurrence and abundance of ammonia-oxidizing archaea and bacteria from the surface to below the water table, in deep soil, and their contributions to nitrification.},
journal = {MicrobiologyOpen},
volume = {6},
number = {4},
pages = {},
pmid = {28523826},
issn = {2045-8827},
mesh = {Ammonia/*metabolism ; Archaea/*classification/genetics/isolation &amp; purification/metabolism ; Bacteria/*classification/genetics/isolation &amp; purification/metabolism ; Bacterial Load ; *Biodiversity ; China ; Groundwater ; Lakes/*microbiology ; Nitrification ; Oxidation-Reduction ; Phylogeny ; Real-Time Polymerase Chain Reaction ; Sequence Analysis, DNA ; *Soil Microbiology ; Switzerland ; },
abstract = {Using molecular biology methods (qualitative and quantitative PCR), we determined the occurrence and abundance of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) from a dry inland soil in Basel, Switzerland, and from the riparian zone of Baiyangdian Lake, China. We also determined the contributions of these microorganisms to ammonia oxidization at different depths based on the nitrification rate. The number of archaeal amoA genes (the key functional gene in AOA) was larger than the number of bacterial amoA genes in each sample, suggesting a dominant role for the AOA amoA gene in environments with a low ammonium concentration. In Baiyangdian Lake, the number of archaeal amoA genes was highest at 6 m and lowest at 12 m from the land-water interface in the soil (at depths from 40 to 60 cm), close to the groundwater, which suggests that AOA become more competitive in environments with a low dissolved oxygen content and are promoted by low pH. The nitrification rate was significantly negatively correlated with depth in the Baiyangdian Lake soil and significantly positively correlated with the number of AOB amoA genes at this site, 6 m from the water.},
}
@article {pmid28520982,
year = {2017},
author = {Qi, L and Yue, L and Feng, D and Qi, F and Li, J and Dong, X},
title = {Genome-wide mRNA processing in methanogenic archaea reveals post-transcriptional regulation of ribosomal protein synthesis.},
journal = {Nucleic acids research},
volume = {45},
number = {12},
pages = {7285-7298},
pmid = {28520982},
issn = {1362-4962},
support = {R21 DE024235/DE/NIDCR NIH HHS/United States ; },
mesh = {Archaeal Proteins/*genetics/metabolism ; Base Sequence ; Cloning, Molecular ; Escherichia coli/genetics/metabolism ; Gene Expression ; *Genome, Archaeal ; Methanococcus/*genetics/metabolism ; Methanosarcinaceae/*genetics/metabolism ; Nucleic Acid Conformation ; Peptide Chain Initiation, Translational ; Protein Isoforms/genetics/metabolism ; *RNA Processing, Post-Transcriptional ; RNA, Messenger/chemistry/*genetics/metabolism ; Recombinant Proteins/genetics/metabolism ; Ribosomal Proteins/*genetics/metabolism ; },
abstract = {Unlike stable RNAs that require processing for maturation, prokaryotic cellular mRNAs generally follow an 'all-or-none' pattern. Herein, we used a 5΄ monophosphate transcript sequencing (5΄P-seq) that specifically captured the 5΄-end of processed transcripts and mapped the genome-wide RNA processing sites (PSSs) in a methanogenic archaeon. Following statistical analysis and stringent filtration, we identified 1429 PSSs, among which 23.5% and 5.4% were located in 5΄ untranslated region (uPSS) and intergenic region (iPSS), respectively. A predominant uridine downstream PSSs served as a processing signature. Remarkably, 5΄P-seq detected overrepresented uPSS and iPSS in the polycistronic operons encoding ribosomal proteins, and the majority upstream and proximal ribosome binding sites, suggesting a regulatory role of processing on translation initiation. The processed transcripts showed increased stability and translation efficiency. Particularly, processing within the tricistronic transcript of rplA-rplJ-rplL enhanced the translation of rplL, which can provide a driving force for the 1:4 stoichiometry of L10 to L12 in the ribosome. Growth-associated mRNA processing intensities were also correlated with the cellular ribosomal protein levels, thereby suggesting that mRNA processing is involved in tuning growth-dependent ribosome synthesis. In conclusion, our findings suggest that mRNA processing-mediated post-transcriptional regulation is a potential mechanism of ribosomal protein synthesis and stoichiometry.},
}
@article {pmid28515720,
year = {2017},
author = {Rajput, A and Kumar, M},
title = {Computational Exploration of Putative LuxR Solos in Archaea and Their Functional Implications in Quorum Sensing.},
journal = {Frontiers in microbiology},
volume = {8},
number = {},
pages = {798},
pmid = {28515720},
issn = {1664-302X},
abstract = {LuxR solos are unexplored in Archaea, despite their vital role in the bacterial regulatory network. They assist bacteria in perceiving acyl homoserine lactones (AHLs) and/or non-AHLs signaling molecules for establishing intraspecies, interspecies, and interkingdom communication. In this study, we explored the potential LuxR solos of Archaea from InterPro v62.0 meta-database employing taxonomic, probable function, distribution, and evolutionary aspects to decipher their role in quorum sensing (QS). Our bioinformatics analyses showed that putative LuxR solos of Archaea shared few conserved domains with bacterial LuxR despite having less similarity within proteins. Functional characterization revealed their ability to bind various AHLs and/or non-AHLs signaling molecules that involve in QS cascades alike bacteria. Further, the phylogenetic study indicates that Archaeal LuxR solos (with less substitution per site) evolved divergently from bacteria and share distant homology along with instances of horizontal gene transfer. Moreover, Archaea possessing putative LuxR solos, exhibit the correlation between taxonomy and ecological niche despite being the inhabitant of diverse habitats like halophilic, thermophilic, barophilic, methanogenic, and chemolithotrophic. Therefore, this study would shed light in deciphering the role of the putative LuxR solos of Archaea to adapt varied habitats via multilevel communication with other organisms using QS.},
}
@article {pmid28512451,
year = {2017},
author = {Wampach, L and Heintz-Buschart, A and Hogan, A and Muller, EEL and Narayanasamy, S and Laczny, CC and Hugerth, LW and Bindl, L and Bottu, J and Andersson, AF and de Beaufort, C and Wilmes, P},
title = {Colonization and Succession within the Human Gut Microbiome by Archaea, Bacteria, and Microeukaryotes during the First Year of Life.},
journal = {Frontiers in microbiology},
volume = {8},
number = {},
pages = {738},
pmid = {28512451},
issn = {1664-302X},
abstract = {Perturbations to the colonization process of the human gastrointestinal tract have been suggested to result in adverse health effects later in life. Although much research has been performed on bacterial colonization and succession, much less is known about the other two domains of life, archaea, and eukaryotes. Here we describe colonization and succession by bacteria, archaea and microeukaryotes during the first year of life (samples collected around days 1, 3, 5, 28, 150, and 365) within the gastrointestinal tract of infants delivered either vaginally or by cesarean section and using a combination of quantitative real-time PCR as well as 16S and 18S rRNA gene amplicon sequencing. Sequences from organisms belonging to all three domains of life were detectable in all of the collected meconium samples. The microeukaryotic community composition fluctuated strongly over time and early diversification was delayed in infants receiving formula milk. Cesarean section-delivered (CSD) infants experienced a delay in colonization and succession, which was observed for all three domains of life. Shifts in prokaryotic succession in CSD infants compared to vaginally delivered (VD) infants were apparent as early as days 3 and 5, which were characterized by increased relative abundances of the genera Streptococcus and Staphylococcus, and a decrease in relative abundance for the genera Bifidobacterium and Bacteroides. Generally, a depletion in Bacteroidetes was detected as early as day 5 postpartum in CSD infants, causing a significantly increased Firmicutes/Bacteroidetes ratio between days 5 and 150 when compared to VD infants. Although the delivery mode appeared to have the strongest influence on differences between the infants, other factors such as a younger gestational age or maternal antibiotics intake likely contributed to the observed patterns as well. Our findings complement previous observations of a delay in colonization and succession of CSD infants, which affects not only bacteria but also archaea and microeukaryotes. This further highlights the need for resolving bacterial, archaeal, and microeukaryotic dynamics in future longitudinal studies of microbial colonization and succession within the neonatal gastrointestinal tract.},
}
@article {pmid28502981,
year = {2017},
author = {Wagner, A and Whitaker, RJ and Krause, DJ and Heilers, JH and van Wolferen, M and van der Does, C and Albers, SV},
title = {Mechanisms of gene flow in archaea.},
journal = {Nature reviews. Microbiology},
volume = {15},
number = {8},
pages = {492-501},
pmid = {28502981},
issn = {1740-1534},
mesh = {Archaea/*genetics ; Evolution, Molecular ; *Gene Flow ; Gene Transfer, Horizontal ; Genes, Bacterial ; *Genome, Archaeal ; Genomics ; },
abstract = {Archaea are diverse, ecologically important, single-celled microorganisms. They have unique functions and features, such as methanogenesis and the composition of their cell envelope, although many characteristics are shared with the other domains of life, either through ancestry or through promiscuous horizontal gene transfer. The exchange of genetic material is a major driving force for genome evolution across the tree of life and has a role in archaeal speciation, adaptation and maintenance of diversity. In this Review, we discuss our current knowledge of archaeal mechanisms of DNA transfer and highlight the role of gene transfer in archaeal evolution.},
}
@article {pmid28500534,
year = {2017},
author = {Aylett, CHS and Duggin, IG},
title = {The Tubulin Superfamily in Archaea.},
journal = {Sub-cellular biochemistry},
volume = {84},
number = {},
pages = {393-417},
doi = {10.1007/978-3-319-53047-5_14},
pmid = {28500534},
issn = {0306-0225},
mesh = {Archaea/*metabolism ; Archaeal Proteins/*metabolism ; Tubulin/*classification/*metabolism ; },
abstract = {In comparison with bacteria and eukaryotes, the large and diverse group of microorganisms known as archaea possess a great diversity of cytoskeletal proteins, including members of the tubulin superfamily. Many species contain FtsZ, CetZ and even possible tubulins; however, some major taxonomic groups do not contain any member of the tubulin superfamily. Studies using the model archaeon, Halferax volcanii have recently been instrumental in defining the fundamental roles of FtsZ and CetZ in archaeal cell division and cell shape regulation. Structural studies of archaeal tubulin superfamily proteins provide a definitive contribution to the cytoskeletal field, showing which protein-types must have developed prior to the divergence of archaea and eukaryotes. Several regions of the globular core domain - the &quot;signature&quot; motifs - combine in the 3D structure of the common molecular fold to form the GTP-binding site. They are the most conserved sequence elements and provide the primary basis for identification of new superfamily members through homology searches. The currently well-characterised proteins also all share a common mechanism of GTP-dependent polymerisation, in which GTP molecules are sandwiched between successive subunits that are arranged in a head-to-tail manner. However, some poorly-characterised archaeal protein families retain only some of the signature motifs and are unlikely to be capable of dynamic polymerisation, since the promotion of depolymerisation by hydrolysis to GDP depends on contributions from both subunits that sandwich the nucleotide in the polymer.},
}
@article {pmid28493148,
year = {2017},
author = {Antranikian, G and Suleiman, M and Schäfers, C and Adams, MWW and Bartolucci, S and Blamey, JM and Birkeland, NK and Bonch-Osmolovskaya, E and da Costa, MS and Cowan, D and Danson, M and Forterre, P and Kelly, R and Ishino, Y and Littlechild, J and Moracci, M and Noll, K and Oshima, T and Robb, F and Rossi, M and Santos, H and Schönheit, P and Sterner, R and Thauer, R and Thomm, M and Wiegel, J and Stetter, KO},
title = {Diversity of bacteria and archaea from two shallow marine hydrothermal vents from Vulcano Island.},
journal = {Extremophiles : life under extreme conditions},
volume = {21},
number = {4},
pages = {733-742},
pmid = {28493148},
issn = {1433-4909},
mesh = {Archaea/*classification/genetics ; Bacteria/*classification/genetics ; Hydrothermal Vents/*microbiology ; Italy ; *Marine Biology ; RNA, Ribosomal, 16S/genetics ; },
abstract = {To obtain new insights into community compositions of hyperthermophilic microorganisms, defined as having optimal growth temperatures of 80 °C and above, sediment and water samples were taken from two shallow marine hydrothermal vents (I and II) with temperatures of 100 °C at Vulcano Island, Italy. A combinatorial approach of denaturant gradient gel electrophoresis (DGGE) and metagenomic sequencing was used for microbial community analyses of the samples. In addition, enrichment cultures, growing anaerobically on selected polysaccharides such as starch and cellulose, were also analyzed by the combinatorial approach. Our results showed a high abundance of hyperthermophilic archaea, especially in sample II, and a comparable diverse archaeal community composition in both samples. In particular, the strains of the hyperthermophilic anaerobic genera Staphylothermus and Thermococcus, and strains of the aerobic hyperthermophilic genus Aeropyrum, were abundant. Regarding the bacterial community, ε-Proteobacteria, especially the genera Sulfurimonas and Sulfurovum, were highly abundant. The microbial diversity of the enrichment cultures changed significantly by showing a high dominance of archaea, particularly the genera Thermococcus and Palaeococcus, depending on the carbon source and the selected temperature.},
}
@article {pmid28489329,
year = {2017},
author = {Dassen, S and Cortois, R and Martens, H and de Hollander, M and Kowalchuk, GA and van der Putten, WH and De Deyn, GB},
title = {Differential responses of soil bacteria, fungi, archaea and protists to plant species richness and plant functional group identity.},
journal = {Molecular ecology},
volume = {26},
number = {15},
pages = {4085-4098},
doi = {10.1111/mec.14175},
pmid = {28489329},
issn = {1365-294X},
mesh = {Archaea/classification ; Bacteria/classification ; *Biodiversity ; *Ecosystem ; Fungi/classification ; Germany ; Mycorrhizae/classification ; Plants/*classification ; *Soil Microbiology ; },
abstract = {Plants are known to influence belowground microbial community structure along their roots, but the impacts of plant species richness and plant functional group (FG) identity on microbial communities in the bulk soil are still not well understood. Here, we used 454-pyrosequencing to analyse the soil microbial community composition in a long-term biodiversity experiment at Jena, Germany. We examined responses of bacteria, fungi, archaea, and protists to plant species richness (communities varying from 1 to 60 sown species) and plant FG identity (grasses, legumes, small herbs, tall herbs) in bulk soil. We hypothesized that plant species richness and FG identity would alter microbial community composition and have a positive impact on microbial species richness. Plant species richness had a marginal positive effect on the richness of fungi, but we observed no such effect on bacteria, archaea and protists. Plant species richness also did not have a large impact on microbial community composition. Rather, abiotic soil properties partially explained the community composition of bacteria, fungi, arbuscular mycorrhizal fungi (AMF), archaea and protists. Plant FG richness did not impact microbial community composition; however, plant FG identity was more effective. Bacterial richness was highest in legume plots and lowest in small herb plots, and AMF and archaeal community composition in legume plant communities was distinct from that in communities composed of other plant FGs. We conclude that soil microbial community composition in bulk soil is influenced more by changes in plant FG composition and abiotic soil properties, than by changes in plant species richness per se.},
}
@article {pmid28487430,
year = {2017},
author = {Mukai, T and Crnković, A and Umehara, T and Ivanova, NN and Kyrpides, NC and Söll, D},
title = {RNA-Dependent Cysteine Biosynthesis in Bacteria and Archaea.},
journal = {mBio},
volume = {8},
number = {3},
pages = {},
pmid = {28487430},
issn = {2150-7511},
support = {R01 GM022854/GM/NIGMS NIH HHS/United States ; R35 GM122560/GM/NIGMS NIH HHS/United States ; },
mesh = {Amino Acyl-tRNA Synthetases/metabolism ; Archaea/*genetics/metabolism ; Archaeal Proteins/genetics/metabolism ; Bacteria/*genetics/metabolism ; Computational Biology ; Crystallography, X-Ray ; Cysteine/*biosynthesis ; Genetic Code ; Genome, Archaeal ; Genome, Bacterial ; Phosphoserine/metabolism ; Protein Binding ; Protein Biosynthesis ; RNA, Archaeal/*metabolism ; RNA, Bacterial/*metabolism ; RNA, Transfer, Amino Acyl/*metabolism ; RNA, Transfer, Cys/*metabolism ; Sulfur/metabolism ; },
abstract = {The diversity of the genetic code systems used by microbes on earth is yet to be elucidated. It is known that certain methanogenic archaea employ an alternative system for cysteine (Cys) biosynthesis and encoding; tRNACys is first acylated with phosphoserine (Sep) by O-phosphoseryl-tRNA synthetase (SepRS) and then converted to Cys-tRNACys by Sep-tRNA:Cys-tRNA synthase (SepCysS). In this study, we searched all genomic and metagenomic protein sequence data in the Integrated Microbial Genomes (IMG) system and at the NCBI to reveal new clades of SepRS and SepCysS proteins belonging to diverse archaea in the four major groups (DPANN, Euryarchaeota, TACK, and Asgard) and two groups of bacteria (&quot;Candidatus Parcubacteria&quot; and Chloroflexi). Bacterial SepRS and SepCysS charged bacterial tRNACys species with cysteine in vitro Homologs of SepCysE, a scaffold protein facilitating SepRS⋅SepCysS complex assembly in Euryarchaeota class I methanogens, are found in a few groups of TACK and Asgard archaea, whereas the C-terminally truncated homologs exist fused or genetically coupled with diverse SepCysS species. Investigation of the selenocysteine (Sec)- and pyrrolysine (Pyl)-utilizing traits in SepRS-utilizing archaea and bacteria revealed that the archaea carrying full-length SepCysE employ Sec and that SepRS is often found in Pyl-utilizing archaea and Chloroflexi bacteria. We discuss possible contributions of the SepRS-SepCysS system for sulfur assimilation, methanogenesis, and other metabolic processes requiring large amounts of iron-sulfur enzymes or Pyl-containing enzymes.IMPORTANCE Comprehensive analyses of all genomic and metagenomic protein sequence data in public databases revealed the distribution and evolution of an alternative cysteine-encoding system in diverse archaea and bacteria. The finding that the SepRS-SepCysS-SepCysE- and the selenocysteine-encoding systems are shared by the Euryarchaeota class I methanogens, the Crenarchaeota AK8/W8A-19 group, and an Asgard archaeon suggests that ancient archaea may have used both systems. In contrast, bacteria may have obtained the SepRS-SepCysS system from archaea. The SepRS-SepCysS system sometimes coexists with a pyrrolysine-encoding system in both archaea and bacteria. Our results provide additional bioinformatic evidence for the contribution of the SepRS-SepCysS system for sulfur assimilation and diverse metabolisms which require vast amounts of iron-sulfur enzymes and proteins. Among these biological activities, methanogenesis, methylamine metabolism, and organohalide respiration may have local and global effects on earth. Taken together, uncultured bacteria and archaea provide an expanded record of the evolution of the genetic code.},
}
@article {pmid28480883,
year = {2017},
author = {Zweerink, S and Kallnik, V and Ninck, S and Nickel, S and Verheyen, J and Blum, M and Wagner, A and Feldmann, I and Sickmann, A and Albers, SV and Bräsen, C and Kaschani, F and Siebers, B and Kaiser, M},
title = {Activity-based protein profiling as a robust method for enzyme identification and screening in extremophilic Archaea.},
journal = {Nature communications},
volume = {8},
number = {},
pages = {15352},
pmid = {28480883},
issn = {2041-1723},
mesh = {Archaeal Proteins/*metabolism ; Extremophiles/*metabolism ; Hydrolases/*metabolism ; Mass Spectrometry ; Proteomics/*methods ; Reproducibility of Results ; Serine/metabolism ; },
abstract = {Archaea are characterized by a unique life style in often environmental extremes but their thorough investigation is currently hampered by a limited set of suitable in vivo research methodologies. Here, we demonstrate that in vivo activity-based protein profiling (ABPP) may be used to sensitively detect either native or heterogeneously expressed active enzymes in living archaea even under these extreme conditions. In combination with the development of a genetically engineered archaeal screening strain, ABPP can furthermore be used in functional enzyme screenings from (meta)genome samples. We anticipate that our ABPP approach may therefore find application in basic archaeal research but also in the discovery of novel enzymes from (meta)genome libraries.},
}
@article {pmid28480138,
year = {2017},
author = {Bolduc, B and Jang, HB and Doulcier, G and You, ZQ and Roux, S and Sullivan, MB},
title = {vConTACT: an iVirus tool to classify double-stranded DNA viruses that infect Archaea and Bacteria.},
journal = {PeerJ},
volume = {5},
number = {},
pages = {e3243},
pmid = {28480138},
issn = {2167-8359},
abstract = {Taxonomic classification of archaeal and bacterial viruses is challenging, yet also fundamental for developing a predictive understanding of microbial ecosystems. Recent identification of hundreds of thousands of new viral genomes and genome fragments, whose hosts remain unknown, requires a paradigm shift away from traditional classification approaches and towards the use of genomes for taxonomy. Here we revisited the use of genomes and their protein content as a means for developing a viral taxonomy for bacterial and archaeal viruses. A network-based analytic was evaluated and benchmarked against authority-accepted taxonomic assignments and found to be largely concordant. Exceptions were manually examined and found to represent areas of viral genome 'sequence space' that are under-sampled or prone to excessive genetic exchange. While both cases are poorly resolved by genome-based taxonomic approaches, the former will improve as viral sequence space is better sampled and the latter are uncommon. Finally, given the largely robust taxonomic capabilities of this approach, we sought to enable researchers to easily and systematically classify new viruses. Thus, we established a tool, vConTACT, as an app at iVirus, where it operates as a fast, highly scalable, user-friendly app within the free and powerful CyVerse cyberinfrastructure.},
}
@article {pmid28464532,
year = {2017},
author = {Sogin, EM and Putnam, HM and Nelson, CE and Anderson, P and Gates, RD},
title = {Correspondence of coral holobiont metabolome with symbiotic bacteria, archaea and Symbiodinium communities.},
journal = {Environmental microbiology reports},
volume = {9},
number = {3},
pages = {310-315},
doi = {10.1111/1758-2229.12541},
pmid = {28464532},
issn = {1758-2229},
mesh = {Alveolata/*growth &amp; development/metabolism ; Animals ; Anthozoa/*microbiology/*parasitology ; Archaea/classification/*growth &amp; development/metabolism ; Biodiversity ; Coral Reefs ; Gammaproteobacteria/*growth &amp; development/metabolism ; Metabolome/physiology ; Symbiosis/*physiology ; Vibrionaceae/*growth &amp; development/metabolism ; },
abstract = {Microbial symbiotic partners, such as those associated with Scleractinian corals, mediate biochemical transformations that influence host performance and survival. While evidence suggests microbial community composition partly accounts for differences in coral physiology, how these symbionts affect metabolic pathways remains underexplored. We aimed to assess functional implications of variation among coral-associated microbial partners in hospite. To this end, we characterized and compared metabolomic profiles and microbial community composition from nine reef-building coral species. These data demonstrate metabolite profiles and microbial communities are species-specific and are correlated to one another. Using Porites spp. as a case study, we present evidence that the relative abundance of different sub-clades of Symbiodinium and bacterial/archaeal families are linked to positive and negative metabolomic signatures. Our data suggest that while some microbial partners benefit the union, others are more opportunistic with potential detriment to the host. Consequently, coral partner choice likely influences cellular metabolic activities and, therefore, holobiont nutrition.},
}
@article {pmid28446901,
year = {2017},
author = {Weber, HS and Habicht, KS and Thamdrup, B},
title = {Anaerobic Methanotrophic Archaea of the ANME-2d Cluster Are Active in a Low-sulfate, Iron-rich Freshwater Sediment.},
journal = {Frontiers in microbiology},
volume = {8},
number = {},
pages = {619},
pmid = {28446901},
issn = {1664-302X},
abstract = {ANaerobic MEthanotrophic (ANME) archaea remove the greenhouse gas methane from anoxic environments and diminish its flux to the atmosphere. High methane removal efficiencies are well documented in marine environments, whereas anaerobic oxidation of methane (AOM) was only recently indicated as an important methane sink in freshwater systems. Freshwater AOM-mediating microorganisms lack taxonomic identification and only little is known about metabolic adaptions to prevailing biogeochemical conditions. One of the first study sites providing information about AOM activity in freshwater sediment is Lake Ørn, a low-sulfate, iron-rich Danish lake. With the aim to identify freshwater AOM-mediating archaea, we incubated AOM-active anoxic, nitrate-free freshwater sediment from Lake Ørn with 13C-labeled methane (13CCH4) and 13C-labeled bicarbonate (13CDIC) and followed the assimilation of 13C into RNA by stable isotope probing. While AOM was active, 13CCH4 and probably also 13CDIC were incorporated into uncultured archaea of the Methanosarcinales-related cluster ANME-2d, whereas other known ANME lineages were not detected. This finding strongly suggests that ANME-2d archaea perform AOM coupled to sulfate and/or iron reduction and may have the capability of mixed assimilation of CH4 and DIC. ANME-2d archaea may thus play an important role in controlling methane emissions from nitrate-depleted and low-sulfate freshwater systems.},
}
@article {pmid28425930,
year = {2017},
author = {Zhang, Y and Kouril, T and Snoep, JL and Siebers, B and Barberis, M and Westerhoff, HV},
title = {The Peculiar Glycolytic Pathway in Hyperthermophylic Archaea: Understanding Its Whims by Experimentation In Silico.},
journal = {International journal of molecular sciences},
volume = {18},
number = {4},
pages = {},
pmid = {28425930},
issn = {1422-0067},
mesh = {Adenosine Triphosphate/metabolism ; Computer Simulation ; Glyceraldehyde 3-Phosphate/metabolism ; Glyceraldehyde-3-Phosphate Dehydrogenases/metabolism ; *Glycolysis ; *Hot Temperature ; Kinetics ; Metabolic Networks and Pathways ; *Models, Biological ; Saccharomyces cerevisiae/metabolism ; Sulfolobus solfataricus/*metabolism ; Systems Biology ; },
abstract = {Mathematical models are key to systems biology where they typically describe the topology and dynamics of biological networks, listing biochemical entities and their relationships with one another. Some (hyper)thermophilic Archaea contain an enzyme, called non-phosphorylating glyceraldehyde-3-phosphate dehydrogenase (GAPN), which catalyzes the direct oxidation of glyceraldehyde-3-phosphate to 3-phosphoglycerate omitting adenosine 5'-triphosphate (ATP) formation by substrate-level-phosphorylation via phosphoglycerate kinase. In this study we formulate three hypotheses that could explain functionally why GAPN exists in these Archaea, and then construct and use mathematical models to test these three hypotheses. We used kinetic parameters of enzymes of Sulfolobus solfataricus (S. solfataricus) which is a thermo-acidophilic archaeon that grows optimally between 60 and 90 °C and between pH 2 and 4. For comparison, we used a model of Saccharomyces cerevisiae (S. cerevisiae), an organism that can live at moderate temperatures. We find that both the first hypothesis, i.e., that the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) plus phosphoglycerate kinase (PGK) route (the alternative to GAPN) is thermodynamically too much uphill and the third hypothesis, i.e., that GAPDH plus PGK are required to carry the flux in the gluconeogenic direction, are correct. The second hypothesis, i.e., that the GAPDH plus PGK route delivers less than the 1 ATP per pyruvate that is delivered by the GAPN route, is only correct when GAPDH reaction has a high rate and 1,3-bis-phosphoglycerate (BPG) spontaneously degrades to 3PG at a high rate.},
}
@article {pmid28424284,
year = {2017},
author = {Liu, Y and Ishino, S and Ishino, Y and Pehau-Arnaudet, G and Krupovic, M and Prangishvili, D},
title = {A Novel Type of Polyhedral Viruses Infecting Hyperthermophilic Archaea.},
journal = {Journal of virology},
volume = {91},
number = {13},
pages = {},
pmid = {28424284},
issn = {1098-5514},
mesh = {DNA Viruses/*classification/genetics/*isolation &amp; purification/ultrastructure ; Gene Order ; Genome, Viral ; Microscopy, Electron ; Open Reading Frames ; Sequence Analysis, DNA ; Sequence Homology, Amino Acid ; Sulfolobus/*virology ; Viral Proteins/genetics ; *Viral Structures ; Virion/chemistry/ultrastructure ; },
abstract = {Encapsidation of genetic material into polyhedral particles is one of the most common structural solutions employed by viruses infecting hosts in all three domains of life. Here, we describe a new virus of hyperthermophilic archaea, Sulfolobus polyhedral virus 1 (SPV1), which condenses its circular double-stranded DNA genome in a manner not previously observed for other known viruses. The genome complexed with virion proteins is wound up sinusoidally into a spherical coil which is surrounded by an envelope and further encased by an outer polyhedral capsid apparently composed of the 20-kDa virion protein. Lipids selectively acquired from the pool of host lipids are integral constituents of the virion. None of the major virion proteins of SPV1 show similarity to structural proteins of known viruses. However, minor structural proteins, which are predicted to mediate host recognition, are shared with other hyperthermophilic archaeal viruses infecting members of the order Sulfolobales The SPV1 genome consists of 20,222 bp and contains 45 open reading frames, only one-fifth of which could be functionally annotated.IMPORTANCE Viruses infecting hyperthermophilic archaea display a remarkable morphological diversity, often presenting architectural solutions not employed by known viruses of bacteria and eukaryotes. Here we present the isolation and characterization of Sulfolobus polyhedral virus 1, which condenses its genome into a unique spherical coil. Due to the original genomic and architectural features of SPV1, the virus should be considered a representative of a new viral family, &quot;Portogloboviridae.&quot;},
}
@article {pmid28420220,
year = {2017},
author = {Michel, CJ},
title = {The Maximal C³ Self-Complementary Trinucleotide Circular Code X in Genes of Bacteria, Archaea, Eukaryotes, Plasmids and Viruses.},
journal = {Life (Basel, Switzerland)},
volume = {7},
number = {2},
pages = {},
pmid = {28420220},
issn = {2075-1729},
abstract = {In 1996, a set X of 20 trinucleotides was identified in genes of both prokaryotes and eukaryotes which has on average the highest occurrence in reading frame compared to its two shifted frames. Furthermore, this set X has an interesting mathematical property as X is a maximal C 3 self-complementary trinucleotide circular code. In 2015, by quantifying the inspection approach used in 1996, the circular code X was confirmed in the genes of bacteria and eukaryotes and was also identified in the genes of plasmids and viruses. The method was based on the preferential occurrence of trinucleotides among the three frames at the gene population level. We extend here this definition at the gene level. This new statistical approach considers all the genes, i.e., of large and small lengths, with the same weight for searching the circular code X . As a consequence, the concept of circular code, in particular the reading frame retrieval, is directly associated to each gene. At the gene level, the circular code X is strengthened in the genes of bacteria, eukaryotes, plasmids, and viruses, and is now also identified in the genes of archaea. The genes of mitochondria and chloroplasts contain a subset of the circular code X . Finally, by studying viral genes, the circular code X was found in DNA genomes, RNA genomes, double-stranded genomes, and single-stranded genomes.},
}
@article {pmid28409190,
year = {2017},
author = {Salah Ud-Din, AIM and Roujeinikova, A},
title = {Methyl-accepting chemotaxis proteins: a core sensing element in prokaryotes and archaea.},
journal = {Cellular and molecular life sciences : CMLS},
volume = {74},
number = {18},
pages = {3293-3303},
pmid = {28409190},
issn = {1420-9071},
mesh = {Archaea/classification/*metabolism ; Chemotaxis ; Membrane Proteins/chemistry/metabolism ; Methyl-Accepting Chemotaxis Proteins/chemistry/*metabolism ; Prokaryotic Cells/classification/*metabolism ; Protein Domains ; Signal Transduction ; Structure-Activity Relationship ; },
abstract = {Chemotaxis is the directed motility by means of which microbes sense chemical cues and relocate towards more favorable environments. Methyl-accepting chemotaxis proteins (MCPs) are the most common receptors in bacteria and archaea. They are arranged as trimers of dimers that, in turn, form hexagonal arrays in the cytoplasmic membrane or in the cytoplasm. Several different classes of MCPs have been identified according to their ligand binding region and membrane topology. MCPs have been further classified based on the length and sequence conservation of their cytoplasmic domains. Clusters of membrane-embedded MCPs often localize to the poles of the cell, whereas cytoplasmic MCPs can be targeted to the poles or distributed throughout the cell body. MCPs play an important role in cell survival, pathogenesis, and biodegradation. Bacterial adaptation to diverse environmental conditions promotes diversity among the MCPs. This review summarizes structure, classification, and structure-activity relationship of the known MCP receptors, with a brief overview of the signal transduction mechanisms in bacteria and archaea.},
}
@article {pmid28402397,
year = {2017},
author = {Peay, KG and von Sperber, C and Cardarelli, E and Toju, H and Francis, CA and Chadwick, OA and Vitousek, PM},
title = {Convergence and contrast in the community structure of Bacteria, Fungi and Archaea along a tropical elevation-climate gradient.},
journal = {FEMS microbiology ecology},
volume = {93},
number = {5},
pages = {},
doi = {10.1093/femsec/fix045},
pmid = {28402397},
issn = {1574-6941},
mesh = {Ammonia/analysis ; Archaea/*classification/genetics ; Bacteria/*classification/genetics ; Biodiversity ; Carbon/analysis ; Fungi/*classification/genetics ; High-Throughput Nucleotide Sequencing ; Microbial Consortia/*physiology ; Nitrogen/analysis ; Phosphorus/analysis ; Soil/*chemistry ; Soil Microbiology ; Tropical Climate ; },
abstract = {Changes in species richness along climatological gradients have been instrumental in developing theories about the general drivers of biodiversity. Previous studies on microbial communities along climate gradients on mountainsides have revealed positive, negative and neutral richness trends. We examined changes in richness and composition of Fungi, Bacteria and Archaea in soil along a 50-1000 m elevation, 280-3280 mm/yr precipitation gradient in Hawai'i. Soil properties and their drivers are exceptionally well understood along this gradient. All three microbial groups responded strongly to the gradient, with community ordinations being similar along axes of environmental conditions (pH, rainfall) and resource availability (nitrogen, phosphorus). However, the form of the richness-climate relationship varied between Fungi (positive linear), Bacteria (unimodal) and Archaea (negative linear). These differences were related to resource-ecology and limiting conditions for each group, with fungal richness increasing most strongly with soil carbon, ammonia-oxidizing Archaea increasing with nitrogen mineralization rate, and Bacteria increasing with both carbon and pH. Reponses to the gradient became increasingly variable at finer taxonomic scales and within any taxonomic group most individual OTUs occurred in narrow climate-elevation ranges. These results show that microbial responses to climate gradients are heterogeneous due to complexity of underlying environmental changes and the diverse ecologies of microbial taxa.},
}
@article {pmid28397816,
year = {2017},
author = {Wong, HL and Visscher, PT and White, RA and Smith, DL and Patterson, MM and Burns, BP},
title = {Dynamics of archaea at fine spatial scales in Shark Bay mat microbiomes.},
journal = {Scientific reports},
volume = {7},
number = {},
pages = {46160},
pmid = {28397816},
issn = {2045-2322},
mesh = {Archaea/*physiology ; Australia ; Bays/*microbiology ; Biodiversity ; Methane/biosynthesis ; Microbial Interactions ; *Microbiota ; },
abstract = {The role of archaea in microbial mats is poorly understood. Delineating the spatial distribution of archaea with mat depth will enable resolution of putative niches in these systems. In the present study, high throughput amplicon sequencing was undertaken in conjunction with analysis of key biogeochemical properties of two mats (smooth and pustular) from Shark Bay, Australia. One-way analysis of similarity tests indicated the archaeal community structures of smooth and pustular mats were significantly different (global R = 1, p = 0.1%). Smooth mats possessed higher archaeal diversity, dominated by Parvarchaeota. The methanogenic community in smooth mats was dominated by hydrogenotrophic Methanomicrobiales, as well as methylotrophic Methanosarcinales, Methanococcales, Methanobacteriales and Methanomassiliicoccaceae. Pustular mats were enriched with Halobacteria and Parvarchaeota. Key metabolisms (bacterial and archaeal) were measured, and the rates of oxygen production/consumption and sulfate reduction were up to four times higher in smooth than in pustular mats. Methane production peaked in the oxic layers and was up to seven-fold higher in smooth than pustular mats. The finding of an abundance of anaerobic methanogens enriched at the surface where oxygen levels were highest, coupled with peak methane production in the oxic zone, suggests putative surface anoxic niches in these microbial mats.},
}
@article {pmid28391963,
year = {2017},
author = {Gophna, U and Allers, T and Marchfelder, A},
title = {Finally, Archaea Get Their CRISPR-Cas Toolbox.},
journal = {Trends in microbiology},
volume = {25},
number = {6},
pages = {430-432},
doi = {10.1016/j.tim.2017.03.009},
pmid = {28391963},
issn = {1878-4380},
mesh = {Archaea/*genetics ; Archaeal Proteins/genetics ; Bacterial Proteins/genetics ; CRISPR-Cas Systems/*genetics ; Clustered Regularly Interspaced Short Palindromic Repeats/*genetics ; DNA End-Joining Repair/genetics ; Gene Deletion ; Gene Editing ; Gene Targeting ; Genes, Archaeal ; Homologous Recombination/genetics ; Methanosarcina/genetics ; RNA, Guide ; },
abstract = {The majority of archaea encode CRISPR-Cas systems but only a few CRISPR-Cas-based genetic tools have been developed for organisms from this domain. Nayak and Metcalf have harnessed a bacterial Cas9 protein for genome editing in Methanosarcina acetivorans, enabling efficient gene deletion and replacement.},
}
@article {pmid28388930,
year = {2017},
author = {Wurzbacher, C and Fuchs, A and Attermeyer, K and Frindte, K and Grossart, HP and Hupfer, M and Casper, P and Monaghan, MT},
title = {Shifts among Eukaryota, Bacteria, and Archaea define the vertical organization of a lake sediment.},
journal = {Microbiome},
volume = {5},
number = {1},
pages = {41},
pmid = {28388930},
issn = {2049-2618},
mesh = {Archaea/*classification/genetics/isolation &amp; purification ; Bacteria/*classification/genetics/isolation &amp; purification ; Ecosystem ; Eukaryota/*classification/genetics/isolation &amp; purification ; Geologic Sediments/*microbiology/*parasitology ; Germany ; Lakes/*microbiology/*parasitology ; Microbiota/genetics ; Water Microbiology ; },
abstract = {BACKGROUND: Lake sediments harbor diverse microbial communities that cycle carbon and nutrients while being constantly colonized and potentially buried by organic matter sinking from the water column. The interaction of activity and burial remained largely unexplored in aquatic sediments. We aimed to relate taxonomic composition to sediment biogeochemical parameters, test whether community turnover with depth resulted from taxonomic replacement or from richness effects, and to provide a basic model for the vertical community structure in sediments.<br><br>METHODS: We analyzed four replicate sediment cores taken from 30-m depth in oligo-mesotrophic Lake Stechlin in northern Germany. Each 30-cm core spanned ca. 170 years of sediment accumulation according to 137Cs dating and was sectioned into layers 1-4 cm thick. We examined a full suite of biogeochemical parameters and used DNA metabarcoding to examine community composition of microbial Archaea, Bacteria, and Eukaryota.<br><br>RESULTS: Community β-diversity indicated nearly complete turnover within the uppermost 30 cm. We observed a pronounced shift from Eukaryota- and Bacteria-dominated upper layers (<5 cm) to Bacteria-dominated intermediate layers (5-14 cm) and to deep layers (>14 cm) dominated by enigmatic Archaea that typically occur in deep-sea sediments. Taxonomic replacement was the prevalent mechanism in structuring the community composition and was linked to parameters indicative of microbial activity (e.g., CO2 and CH4 concentration, bacterial protein production). Richness loss played a lesser role but was linked to conservative parameters (e.g., C, N, P) indicative of past conditions.<br><br>CONCLUSIONS: By including all three domains, we were able to directly link the exponential decay of eukaryotes with the active sediment microbial community. The dominance of Archaea in deeper layers confirms earlier findings from marine systems and establishes freshwater sediments as a potential low-energy environment, similar to deep sea sediments. We propose a general model of sediment structure and function based on microbial characteristics and burial processes. An upper &quot;replacement horizon&quot; is dominated by rapid taxonomic turnover with depth, high microbial activity, and biotic interactions. A lower &quot;depauperate horizon&quot; is characterized by low taxonomic richness, more stable &quot;low-energy&quot; conditions, and a dominance of enigmatic Archaea.},
}
@article {pmid28373277,
year = {2017},
author = {Heider, MR and Burkhart, BW and Santangelo, TJ and Gardner, AF},
title = {Defining the RNaseH2 enzyme-initiated ribonucleotide excision repair pathway in Archaea.},
journal = {The Journal of biological chemistry},
volume = {292},
number = {21},
pages = {8835-8845},
pmid = {28373277},
issn = {1083-351X},
support = {R01 GM100329/GM/NIGMS NIH HHS/United States ; },
mesh = {Archaeal Proteins/genetics/*metabolism ; *DNA Breaks, Single-Stranded ; DNA Ligases/genetics/metabolism ; DNA Polymerase beta/genetics/metabolism ; DNA Repair/*physiology ; DNA, Archaeal/genetics/*metabolism ; Ribonuclease H/genetics/*metabolism ; Thermococcus/genetics/*metabolism ; },
abstract = {Incorporation of ribonucleotides during DNA replication has severe consequences for genome stability. Although eukaryotes possess a number of redundancies for initiating and completing repair of misincorporated ribonucleotides, archaea such as Thermococcus rely only upon RNaseH2 to initiate the pathway. Because Thermococcus DNA polymerases incorporate as many as 1,000 ribonucleotides per genome, RNaseH2 must be efficient at recognizing and nicking at embedded ribonucleotides to ensure genome integrity. Here, we show that ribonucleotides are incorporated by the hyperthermophilic archaeon Thermococcus kodakarensis both in vitro and in vivo and a robust ribonucleotide excision repair pathway is critical to keeping incorporation levels low in wild-type cells. Using pre-steady-state and steady-state kinetics experiments, we also show that archaeal RNaseH2 rapidly cleaves at embedded ribonucleotides (200-450 s-1), but exhibits an ∼1,000-fold slower turnover rate (0.06-0.17 s-1), suggesting a potential role for RNaseH2 in protecting or marking nicked sites for further processing. We found that following RNaseH2 cleavage, the combined activities of polymerase B (PolB), flap endonuclease (Fen1), and DNA ligase are required to complete ribonucleotide processing. PolB formed a ribonucleotide-containing flap by strand displacement synthesis that was cleaved by Fen1, and DNA ligase sealed the nick for complete repair. Our study reveals conservation of the overall mechanism of ribonucleotide excision repair across domains of life. The lack of redundancies in ribonucleotide repair in archaea perhaps suggests a more ancestral form of ribonucleotide excision repair compared with the eukaryotic pathway.},
}
@article {pmid28368387,
year = {2017},
author = {Paul, BG and Burstein, D and Castelle, CJ and Handa, S and Arambula, D and Czornyj, E and Thomas, BC and Ghosh, P and Miller, JF and Banfield, JF and Valentine, DL},
title = {Retroelement-guided protein diversification abounds in vast lineages of Bacteria and Archaea.},
journal = {Nature microbiology},
volume = {2},
number = {},
pages = {17045},
pmid = {28368387},
issn = {2058-5276},
support = {R01 AI096838/AI/NIAID NIH HHS/United States ; },
mesh = {Archaea/classification/*genetics/metabolism ; Archaeal Proteins/*genetics ; Bacteria/classification/*genetics/metabolism ; Bacterial Proteins/*genetics ; *Evolution, Molecular ; Genome, Archaeal ; Genome, Bacterial ; Genomics ; Nanoarchaeota/genetics/metabolism ; Phylogeny ; RNA-Directed DNA Polymerase/genetics ; Retroelements/*genetics ; },
abstract = {Major radiations of enigmatic Bacteria and Archaea with large inventories of uncharacterized proteins are a striking feature of the Tree of Life1-5. The processes that led to functional diversity in these lineages, which may contribute to a host-dependent lifestyle, are poorly understood. Here, we show that diversity-generating retroelements (DGRs), which guide site-specific protein hypervariability6-8, are prominent features of genomically reduced organisms from the bacterial candidate phyla radiation (CPR) and as yet uncultivated phyla belonging to the DPANN (Diapherotrites, Parvarchaeota, Aenigmarchaeota, Nanoarchaeota and Nanohaloarchaea) archaeal superphylum. From reconstructed genomes we have defined monophyletic bacterial and archaeal DGR lineages that expand the known DGR range by 120% and reveal a history of horizontal retroelement transfer. Retroelement-guided diversification is further shown to be active in current CPR and DPANN populations, with an assortment of protein targets potentially involved in attachment, defence and regulation. Based on observations of DGR abundance, function and evolutionary history, we find that targeted protein diversification is a pronounced trait of CPR and DPANN phyla compared to other bacterial and archaeal phyla. This diversification mechanism may provide CPR and DPANN organisms with a versatile tool that could be used for adaptation to a dynamic, host-dependent existence.},
}
@article {pmid28360898,
year = {2017},
author = {Wang, J and Kan, J and Zhang, X and Xia, Z and Zhang, X and Qian, G and Miao, Y and Leng, X and Sun, J},
title = {Archaea Dominate the Ammonia-Oxidizing Community in Deep-Sea Sediments of the Eastern Indian Ocean-from the Equator to the Bay of Bengal.},
journal = {Frontiers in microbiology},
volume = {8},
number = {},
pages = {415},
pmid = {28360898},
issn = {1664-302X},
abstract = {Ammonia-oxidizing Archaea (AOA) and ammonia-oxidizing Bacteria (AOB) oxidize ammonia to nitrite, and therefore play essential roles in nitrification and global nitrogen cycling. To better understand the population structure and the distribution of AOA and AOB in the deep Eastern Indian Ocean (EIO), nine surface sediment samples (>3,300 m depth) were collected during the inter-monsoon Spring 2013. One sediment sample from the South China Sea (SCS; 2,510 m) was also included for comparison. The community composition, species richness, and diversity were characterized by clone libraries (total 1,238 clones), and higher diversity of archaeal amoA genes than bacterial amoA genes was observed in all analyzed samples. Real time qPCR analysis also demonstrated higher abundances (gene copy numbers) of archaeal amoA genes than bacterial amoA genes, and the ratios of AOA/AOB ranged from 1.42 to 8.49 among sites. In addition, unique and distinct clades were found in both reconstructed AOA and AOB phylogeny, suggesting the presence of niche-specific ammonia-oxidizing microorganisms in the EIO. The distribution pattern of both archaeal and bacterial amoA genes revealed by NMDS (non-metric multidimensional scaling) showed a distinct geographic separation of the sample from the SCS and most of the samples from the EIO following nitrogen gradients. Higher abundance and diversity of archaeal amoA genes indicated that AOA may play a more important role than AOB in the deep Indian Ocean. Environmental parameters shaping the distribution pattern of AOA were different from that of AOB, indicating distinct metabolic characteristics and/or adaptation mechanisms between AOA and AOB in the EIO, especially in deep-sea environments.},
}
@article {pmid28350393,
year = {2017},
author = {Hernsdorf, AW and Amano, Y and Miyakawa, K and Ise, K and Suzuki, Y and Anantharaman, K and Probst, A and Burstein, D and Thomas, BC and Banfield, JF},
title = {Potential for microbial H2 and metal transformations associated with novel bacteria and archaea in deep terrestrial subsurface sediments.},
journal = {The ISME journal},
volume = {11},
number = {8},
pages = {1915-1929},
pmid = {28350393},
issn = {1751-7370},
mesh = {Archaea/*metabolism ; Bacteria/*metabolism ; Carbon/metabolism ; Hydrogen/chemistry/*metabolism ; Hydrogenase ; Metals/chemistry/*metabolism ; Methane/metabolism ; Nitrogen/metabolism ; Oxidation-Reduction ; Radioactive Waste ; Soil/*chemistry ; Soil Microbiology ; Sulfur/metabolism ; Waste Disposal Facilities ; },
abstract = {Geological sequestration in deep underground repositories is the prevailing proposed route for radioactive waste disposal. After the disposal of radioactive waste in the subsurface, H2 may be produced by corrosion of steel and, ultimately, radionuclides will be exposed to the surrounding environment. To evaluate the potential for microbial activities to impact disposal systems, we explored the microbial community structure and metabolic functions of a sediment-hosted ecosystem at the Horonobe Underground Research Laboratory, Hokkaido, Japan. Overall, we found that the ecosystem hosted organisms from diverse lineages, including many from the phyla that lack isolated representatives. The majority of organisms can metabolize H2, often via oxidative [NiFe] hydrogenases or electron-bifurcating [FeFe] hydrogenases that enable ferredoxin-based pathways, including the ion motive Rnf complex. Many organisms implicated in H2 metabolism are also predicted to catalyze carbon, nitrogen, iron and sulfur transformations. Notably, iron-based metabolism is predicted in a novel lineage of Actinobacteria and in a putative methane-oxidizing ANME-2d archaeon. We infer an ecological model that links microorganisms to sediment-derived resources and predict potential impacts of microbial activity on H2 consumption and retardation of radionuclide migration.},
}
@article {pmid28344572,
year = {2017},
author = {van de Pol, JA and van Best, N and Mbakwa, CA and Thijs, C and Savelkoul, PH and Arts, IC and Hornef, MW and Mommers, M and Penders, J},
title = {Gut Colonization by Methanogenic Archaea Is Associated with Organic Dairy Consumption in Children.},
journal = {Frontiers in microbiology},
volume = {8},
number = {},
pages = {355},
pmid = {28344572},
issn = {1664-302X},
abstract = {The gut microbiota represents a complex and diverse ecosystem with a profound impact on human health, promoting immune maturation, and host metabolism as well as colonization resistance. Important members that have often been disregarded are the methanogenic archaea. Methanogenic archaea reduce hydrogen levels via the production of methane, thereby stimulating food fermentation by saccharolytic bacteria. On the other hand, colonization by archaea has been suggested to promote a number of gastrointestinal and metabolic diseases such as colorectal cancer, inflammatory bowel disease, and obesity. Archaea have been shown to be absent during infancy while omnipresent in school-aged children, suggesting that colonization may result from environmental exposure during childhood. The factors that determine the acquisition of methanogenic archaea, however, have remained undefined. Therefore, we aimed to explore determinants associated with the acquisition of the two main gastrointestinal archaeal species, Methanobrevibacter smithii and Methanosphaera stadtmanae, in children. Within the context of the KOALA Birth Cohort Study, fecal samples from 472 children aged 6-10 years were analyzed for the abundance of M. smithii and M. stadtmanae using qPCR. Environmental factors such as diet, lifestyle, hygiene, child rearing, and medication were recorded by repeated questionnaires. The relationship between these determinants and the presence and abundance of archaea was analyzed by logistic and linear regression respectively. Three hundred and sixty-nine out of the 472 children (78.2%) were colonized by M. smithii, and 39 out of the 472 children (8.3%) by M. stadtmanae. The consumption of organic yogurt (odds ratio: 4.25, CI95: 1.51; 11.95) and the consumption of organic milk (odds ratio: 5.58, CI95: 1.83; 17.01) were positively associated with the presence of M. smithii. We subsequently screened raw milk, processed milk, and yogurt samples for methanogens. We identified milk products as possible source for M. smithii, but not M. stadtmanae. In conclusion, M. smithii seems present in milk products and their consumption may determine archaeal gut colonization in children. For the first time, a large variety of determinants have been explored in association with gut colonization by methanogenic archaea. Although more information is needed to confirm and unravel the mechanisms in detail, it provides new insights on microbial colonization processes in early life.},
}
@article {pmid28340330,
year = {2017},
author = {Blombach, F and Grohmann, D},
title = {Same same but different: The evolution of TBP in archaea and their eukaryotic offspring.},
journal = {Transcription},
volume = {8},
number = {3},
pages = {162-168},
pmid = {28340330},
issn = {2154-1272},
mesh = {*Archaea/genetics/metabolism ; *Archaeal Proteins/genetics/metabolism ; DNA, Archaeal/genetics/metabolism ; DNA-Directed RNA Polymerases/genetics/metabolism ; *Evolution, Molecular ; Promoter Regions, Genetic/physiology ; *Transcription Factor TFIIB/metabolism ; },
abstract = {Transcription factors TBP and TF(II)B assemble with RNA polymerase at the promoter DNA forming the initiation complex. Despite a high degree of conservation, the molecular binding mechanisms of archaeal and eukaryotic TBP and TF(II)B differ significantly. Based on recent biophysical data, we speculate how the mechanisms co-evolved with transcription regulation and TBP multiplicity.},
}
@article {pmid28330764,
year = {2017},
author = {Eichler, J and Guan, Z},
title = {Lipid sugar carriers at the extremes: The phosphodolichols Archaea use in N-glycosylation.},
journal = {Biochimica et biophysica acta. Molecular and cell biology of lipids},
volume = {1862},
number = {6},
pages = {589-599},
pmid = {28330764},
issn = {1388-1981},
support = {R01 EY023666/EY/NEI NIH HHS/United States ; R01 GM120594/GM/NIGMS NIH HHS/United States ; U54 GM069338/GM/NIGMS NIH HHS/United States ; },
mesh = {Archaea/genetics/*metabolism ; Carbohydrates/genetics ; Dolichol Phosphates/genetics/*metabolism ; Glycosylation ; },
abstract = {N-glycosylation, a post-translational modification whereby glycans are covalently linked to select Asn residues of target proteins, occurs in all three domains of life. Across evolution, the N-linked glycans are initially assembled on phosphorylated cytoplasmically-oriented polyisoprenoids, with polyprenol (mainly C55 undecaprenol) fulfilling this role in Bacteria and dolichol assuming this function in Eukarya and Archaea. The eukaryal and archaeal versions of dolichol can, however, be distinguished on the basis of their length, degree of saturation and by other traits. As is true for many facets of their biology, Archaea, best known in their capacity as extremophiles, present unique approaches for synthesizing phosphodolichols. At the same time, general insight into the assembly and processing of glycan-bearing phosphodolichols has come from studies of the archaeal enzymes responsible. In this review, these and other aspects of archaeal phosphodolichol biology are addressed.},
}
@article {pmid28321126,
year = {2017},
author = {Lazar, CS and Baker, BJ and Seitz, KW and Teske, AP},
title = {Genomic reconstruction of multiple lineages of uncultured benthic archaea suggests distinct biogeochemical roles and ecological niches.},
journal = {The ISME journal},
volume = {11},
number = {4},
pages = {1058},
doi = {10.1038/ismej.2017.8},
pmid = {28321126},
issn = {1751-7370},
}
@article {pmid28321009,
year = {2017},
author = {McGlynn, SE},
title = {Energy Metabolism during Anaerobic Methane Oxidation in ANME Archaea.},
journal = {Microbes and environments},
volume = {32},
number = {1},
pages = {5-13},
pmid = {28321009},
issn = {1347-4405},
mesh = {Anaerobiosis ; Archaea/*metabolism ; *Energy Metabolism ; Metabolic Networks and Pathways ; Methane/*metabolism ; Oxidation-Reduction ; },
abstract = {Anaerobic methane oxidation in archaea is often presented to operate via a pathway of &quot;reverse methanogenesis&quot;. However, if the cumulative reactions of a methanogen are run in reverse there is no apparent way to conserve energy. Recent findings suggest that chemiosmotic coupling enzymes known from their use in methylotrophic and acetoclastic methanogens-in addition to unique terminal reductases-biochemically facilitate energy conservation during complete CH4 oxidation to CO2. The apparent enzyme modularity of these organisms highlights how microbes can arrange their energy metabolisms to accommodate diverse chemical potentials in various ecological niches, even in the extreme case of utilizing &quot;reverse&quot; thermodynamic potentials.},
}
@article {pmid28286499,
year = {2017},
author = {Knüppel, R and Kuttenberger, C and Ferreira-Cerca, S},
title = {Toward Time-Resolved Analysis of RNA Metabolism in Archaea Using 4-Thiouracil.},
journal = {Frontiers in microbiology},
volume = {8},
number = {},
pages = {286},
pmid = {28286499},
issn = {1664-302X},
abstract = {Archaea are widespread organisms colonizing almost every habitat on Earth. However, the molecular biology of archaea still remains relatively uncharacterized. RNA metabolism is a central cellular process, which has been extensively analyzed in both bacteria and eukarya. In contrast, analysis of RNA metabolism dynamic in archaea has been limited to date. To facilitate analysis of the RNA metabolism dynamic at a system-wide scale in archaea, we have established non-radioactive pulse labeling of RNA, using the nucleotide analog 4-thiouracil (4TU) in two commonly used model archaea: the halophile Euryarchaeota Haloferax volcanii, and the thermo-acidophile Crenarchaeota Sulfolobus acidocaldarius. In this work, we show that 4TU pulse labeling can be efficiently performed in these two organisms in a dose- and time-dependent manner. In addition, our results suggest that uracil prototrophy had no critical impact on the overall 4TU incorporation in RNA molecules. Accordingly, our work suggests that 4TU incorporation can be widely performed in archaea, thereby expanding the molecular toolkit to analyze archaeal gene expression network dynamic in unprecedented detail.},
}
@article {pmid28270994,
year = {2017},
author = {Qi, X and Carberry, DM and Cai, C and Hu, S and Yuan, Z and Dunlop, HR and Guo, J},
title = {Optical sorting and cultivation of denitrifying anaerobic methane oxidation archaea.},
journal = {Biomedical optics express},
volume = {8},
number = {2},
pages = {934-942},
pmid = {28270994},
issn = {2156-7085},
abstract = {Denitrifying anaerobic methane oxidizing (DAMO) microorganisms play an important role in the global carbon and nitrogen cycles as they are able to mediate methane oxidation using nitrite/nitrate under anoxic conditions. However, the physiological properties of DAMO microorganisms remain poorly understood, partially since the organisms are difficult to isolate or cultivate in pure culture and partially because of their long cultivation time. In this study, DAMO cell sorting has been conducted by integrating optical tweezers within enclosed microfluidic chips. This integrated cell sorting method has high purity, low infection rates, and causes no discernable harm to cell viability. The purity of the sorted cells was controlled by the microfluidic chip structure design and operation, while the cell viability was verified by imaging the cultured DAMO archaea after 420 days.},
}
@article {pmid28261173,
year = {2017},
author = {Bhute, SS and Suryavanshi, MV and Joshi, SM and Yajnik, CS and Shouche, YS and Ghaskadbi, SS},
title = {Gut Microbial Diversity Assessment of Indian Type-2-Diabetics Reveals Alterations in Eubacteria, Archaea, and Eukaryotes.},
journal = {Frontiers in microbiology},
volume = {8},
number = {},
pages = {214},
pmid = {28261173},
issn = {1664-302X},
abstract = {Diabetes in India has distinct genetic, nutritional, developmental and socio-economic aspects; owing to the fact that changes in gut microbiota are associated with diabetes, we employed semiconductor-based sequencing to characterize gut microbiota of diabetic subjects from this region. We suggest consolidated dysbiosis of eubacterial, archaeal and eukaryotic components in the gut microbiota of newly diagnosed (New-DMs) and long-standing diabetic subjects (Known-DMs) compared to healthy subjects (NGTs). Increased abundance of phylum Firmicutes (p = 0.010) and Operational Taxonomic Units (OTUs) of Lactobacillus (p < 0.01) were observed in Known-DMs subjects along with the concomitant graded decrease in butyrate-producing bacterial families like Ruminococcaceae and Lachnospiraceae. Eukaryotes and fungi were the least affected components in these subjects but archaea, except Methanobrevibacter were significantly decreased in them. The two dominant archaea viz. Methanobrevibacater and Methanosphaera followed opposite trends in abundance from NGTs to Known-DMs subjects. There was a substantial reduction in eubacteria, with a noticeable decrease in Bacteroidetes phylum (p = 0.098) and an increased abundance of fungi in New-DMs subjects. Likewise, opportunistic fungal pathogens such as Aspergillus, Candida were found to be enriched in New-DMs subjects. Analysis of eubacterial interaction network revealed disease-state specific patterns of ecological interactions, suggesting the distinct behavior of individual components of eubacteria in response to the disease. PERMANOVA test indicated that the eubacterial component was associated with diabetes-related risk factors like high triglyceride (p = 0.05), low HDL (p = 0.03), and waist-to-hip ratio (p = 0.02). Metagenomic imputation of eubacteria depict deficiencies of various essential functions such as carbohydrate metabolism, amino acid metabolism etc. in New-DMs subjects. Results presented here shows that in diabetes, microbial dysbiosis may not be just limited to eubacteria. Due to the inter-linked metabolic interactions among the eubacteria, archaea and eukarya in the gut, it may extend into other two domains leading to trans-domain dysbiosis in microbiota. Our results thus contribute to and expand the identification of biomarkers in diabetes.},
}
@article {pmid28249694,
year = {2017},
author = {Rosselló-Móra, R and Trujillo, ME and Sutcliffe, IC},
title = {Introducing a Digital Protologue: A timely move towards a database-driven systematics of Archaea and Bacteria.},
journal = {Systematic and applied microbiology},
volume = {40},
number = {3},
pages = {121-122},
doi = {10.1016/j.syapm.2017.02.001},
pmid = {28249694},
issn = {1618-0984},
mesh = {Archaea/*classification ; Bacteria/*classification ; *Databases, Factual ; Phylogeny ; },
}
@article {pmid28249125,
year = {2017},
author = {He, Y and Hu, W and Ma, D and Lan, H and Yang, Y and Gao, Y},
title = {Abundance and diversity of ammonia-oxidizing archaea and bacteria in the rhizosphere soil of three plants in the Ebinur Lake wetland.},
journal = {Canadian journal of microbiology},
volume = {63},
number = {7},
pages = {573-582},
doi = {10.1139/cjm-2016-0492},
pmid = {28249125},
issn = {1480-3275},
mesh = {Amaranthaceae ; Ammonia/*metabolism ; Archaea/*genetics/isolation &amp; purification/metabolism ; Asteraceae ; Bacteria/*genetics/isolation &amp; purification/metabolism ; Biodiversity ; China ; DNA, Ribosomal/chemistry/genetics ; Ecosystem ; Lakes ; Oxidation-Reduction ; Phylogeny ; Poaceae ; Rhizosphere ; Sequence Analysis, DNA ; Soil/chemistry ; *Soil Microbiology ; Wetlands ; },
abstract = {Ammonia oxidation is carried out by ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA). The Ebinur Lake wetland is the best example of a temperate arid zone wetland ecosystem in China. Soil samples were collected from rhizosphere and non-rhizosphere soil containing Halocnemum strobilaceum (samples H and H'), Phragmites australis (samples R and R'), and Karelinia caspia (samples K and K') to study the relationship between environmental factors and the community structure of AOB and AOA. Phylogenetic analysis showed that the AOA sequences belonged to the Nitrosopumilus and Nitrososphaera clusters. AOB were grouped into Nitrosospira sp. and Nitrosomonas sp. Quantitative polymerase chain reaction results showed that the AOA abundance ranged from 2.09 × 104 to 2.94 × 105 gene copies/g soil. The highest number of AOA was detected in sample K, followed by samples R and H. AOB abundance varied between 2.91 × 105 and 1.05 × 106 gene copies/g soil, which was higher than that of AOA. Redundancy analysis indicated that electrical conductivity, pH, and NH4+-N might influence the community structure of AOA and AOB. AOB might play a more crucial role than AOA in ammonia oxidation based on AOB's higher diversity and abundance in the Ebinur Lake wetland in Xinjiang.},
}
@article {pmid28229970,
year = {2017},
author = {Rani, SB and Balamurugan, R and Ramakrishna, BS},
title = {Molecular analysis of the human faecal archaea in a southern Indian population.},
journal = {Journal of biosciences},
volume = {42},
number = {1},
pages = {113-119},
pmid = {28229970},
issn = {0973-7138},
mesh = {Adolescent ; Adult ; Age Factors ; Aged ; Archaea/classification/*genetics/isolation &amp; purification ; Child ; Child, Preschool ; Feces/*microbiology ; Female ; Gastrointestinal Microbiome/*genetics ; Humans ; India ; Infant ; Infant, Newborn ; Male ; Methanobrevibacter/classification/*genetics/isolation &amp; purification ; Middle Aged ; *Phylogeny ; RNA, Ribosomal, 16S/genetics ; },
abstract = {Archaea are an important constituent of the human gut microbiota, but there is no information on human gut archaea in an Indian population. In this study, faecal samples were obtained from different age groups (neonatal babies, preschool children, school-going children, adolescents, adults and elderly) of a southern Indian population, and from a tribal population also resident in southern India). 16S rRNA gene sequences specific to Archaea were amplified from pooled faecal DNA in each group, sequenced, and aligned against the NCBI database. Of the 806 adequate sequences in the study, most aligned with 22 known sequences. There were 9 novel sequences in the present study. All sequences were deposited in the GenBank nucleotide sequence database with the following accession numbers: KF607113 - KF607918. Methanobrevibacter was the most prevalent genus among all the age groups accounting for 98% in neonates, 96% in post-weaning, and 100% each in preschool, school and adult population. In the elderly, Methanobrevibacter accounted for 96% and in tribal adults, 99% of the clones belonged to Methanobrevibacter genus. Other genera detected included Caldisphaera, Halobaculum, Methanosphaeraand Thermogymnomonas. Methanobrevibacter smithii predominated in all age groups, accounting for 749 (92.9%) of the 806 sequences. Archaea can be found in the faeces of southern Indian residents immediately after birth. Methanobrevibacter smithii was the dominant faecal archeon in all age groups, with other genera being found at the extremes of age.},
}
@article {pmid28221378,
year = {2017},
author = {Leriche, G and Cifelli, JL and Sibucao, KC and Patterson, JP and Koyanagi, T and Gianneschi, NC and Yang, J},
title = {Characterization of drug encapsulation and retention in archaea-inspired tetraether liposomes.},
journal = {Organic &amp; biomolecular chemistry},
volume = {15},
number = {10},
pages = {2157-2162},
doi = {10.1039/c6ob02832b},
pmid = {28221378},
issn = {1477-0539},
mesh = {Antineoplastic Agents/*analysis/*chemistry ; Archaea/*chemistry ; *Drug Compounding ; Humans ; KB Cells ; Lipids/chemistry ; Liposomes/chemical synthesis/*chemistry ; },
abstract = {The passive leakage of small molecules across membranes is a major limitation of liposomal drug formulations. Here, we evaluate the leakage of 3 clinically used chemotherapeutic agents (cytarabine, methotrexate and vincristine) encapsulated in liposomes comprised of a synthetic, archaea-inspired, membrane-spanning tetraether lipid. Liposomes comprised of the pure tetraether lipid exhibited superior retention of both a neutrally and positively charged drug (up to an ∼9-fold decrease in the rate of drug leakage) compared to liposomes formed from a commercial diacyl lipid, while exhibiting a similar retention of a negatively charged drug that did not appreciably leak from either type of liposome. We also demonstrate that liposomes made of the archaea-inspired lipid can be used for the delivery of encapsulated small molecules into living cells.},
}
@article {pmid28211189,
year = {2017},
author = {Qin, W and Meinhardt, KA and Moffett, JW and Devol, AH and Virginia Armbrust, E and Ingalls, AE and Stahl, DA},
title = {Influence of oxygen availability on the activities of ammonia-oxidizing archaea.},
journal = {Environmental microbiology reports},
volume = {9},
number = {3},
pages = {250-256},
doi = {10.1111/1758-2229.12525},
pmid = {28211189},
issn = {1758-2229},
mesh = {Ammonia/*metabolism ; Anaerobiosis/*physiology ; Archaea/growth &amp; development/*metabolism ; Hydrogen Peroxide/pharmacology ; Nitrous Oxide/*metabolism ; Oceans and Seas ; Oxidation-Reduction ; Oxygen/*metabolism ; },
abstract = {Recent studies point to the importance of oxygen (O2) in controlling the distribution and activity of marine ammonia-oxidizing archaea (AOA), one of the most abundant prokaryotes in the ocean. The AOA are associated with regions of low O2 tension in oceanic oxygen minimum zones (OMZs), and O2 availability is suggested to influence their production of the ozone-depleting greenhouse gas nitrous oxide (N2 O). We show that marine AOA available in pure culture sustain high ammonia oxidation activity at low μM O2 concentrations, characteristic of suboxic regions of OMZs (<10 µM O2), and that atmospheric concentrations of O2 may inhibit the growth of some environmental populations. We quantify the increasing N2 O production by marine AOA with decreasing O2 tensions, consistent with the plausibility of an AOA contribution to the accumulation of N2 O at the oxic-anoxic redox boundaries of OMZs. Variable sensitivity to peroxide also suggests that endogenous or exogenous reactive oxygen species are of importance in determining the environmental distribution of some populations.},
}
@article {pmid28194147,
year = {2017},
author = {Bartelme, RP and McLellan, SL and Newton, RJ},
title = {Freshwater Recirculating Aquaculture System Operations Drive Biofilter Bacterial Community Shifts around a Stable Nitrifying Consortium of Ammonia-Oxidizing Archaea and Comammox Nitrospira.},
journal = {Frontiers in microbiology},
volume = {8},
number = {},
pages = {101},
pmid = {28194147},
issn = {1664-302X},
abstract = {Recirculating aquaculture systems (RAS) are unique engineered ecosystems that minimize environmental perturbation by reducing nutrient pollution discharge. RAS typically employ a biofilter to control ammonia levels produced as a byproduct of fish protein catabolism. Nitrosomonas (ammonia-oxidizing), Nitrospira, and Nitrobacter (nitrite-oxidizing) species are thought to be the primary nitrifiers present in RAS biofilters. We explored this assertion by characterizing the biofilter bacterial and archaeal community of a commercial scale freshwater RAS that has been in operation for >15 years. We found the biofilter community harbored a diverse array of bacterial taxa (>1000 genus-level taxon assignments) dominated by Chitinophagaceae (~12%) and Acidobacteria (~9%). The bacterial community exhibited significant composition shifts with changes in biofilter depth and in conjunction with operational changes across a fish rearing cycle. Archaea also were abundant, and were comprised solely of a low diversity assemblage of Thaumarchaeota (>95%), thought to be ammonia-oxidizing archaea (AOA) from the presence of AOA ammonia monooxygenase genes. Nitrosomonas were present at all depths and time points. However, their abundance was >3 orders of magnitude less than AOA and exhibited significant depth-time variability not observed for AOA. Phylogenetic analysis of the nitrite oxidoreductase beta subunit (nxrB) gene indicated two distinct Nitrospira populations were present, while Nitrobacter were not detected. Subsequent identification of Nitrospira ammonia monooxygenase alpha subunit genes in conjunction with the phylogenetic placement and quantification of the nxrB genotypes suggests complete ammonia-oxidizing (comammox) and nitrite-oxidizing Nitrospira populations co-exist with relatively equivalent and stable abundances in this system. It appears RAS biofilters harbor complex microbial communities whose composition can be affected directly by typical system operations while supporting multiple ammonia oxidation lifestyles within the nitrifying consortium.},
}
@article {pmid28191504,
year = {2017},
author = {Ma, B and Dai, Z and Wang, H and Dsouza, M and Liu, X and He, Y and Wu, J and Rodrigues, JL and Gilbert, JA and Brookes, PC and Xu, J},
title = {Distinct Biogeographic Patterns for Archaea, Bacteria, and Fungi along the Vegetation Gradient at the Continental Scale in Eastern China.},
journal = {mSystems},
volume = {2},
number = {1},
pages = {},
pmid = {28191504},
issn = {2379-5077},
abstract = {The natural forest ecosystem in Eastern China, from tropical forest to boreal forest, has declined due to cropland development during the last 300 years, yet little is known about the historical biogeographic patterns and driving processes for the major domains of microorganisms along this continental-scale natural vegetation gradient. We predicted the biogeographic patterns of soil archaeal, bacterial, and fungal communities across 110 natural forest sites along a transect across four vegetation zones in Eastern China. The distance decay relationships demonstrated the distinct biogeographic patterns of archaeal, bacterial, and fungal communities. While historical processes mainly influenced bacterial community variations, spatially autocorrelated environmental variables mainly influenced the fungal community. Archaea did not display a distance decay pattern along the vegetation gradient. Bacterial community diversity and structure were correlated with the ratio of acid oxalate-soluble Fe to free Fe oxides (Feo/Fed ratio). Fungal community diversity and structure were influenced by dissolved organic carbon (DOC) and free aluminum (Ald), respectively. The role of these environmental variables was confirmed by the correlations between dominant operational taxonomic units (OTUs) and edaphic variables. However, most of the dominant OTUs were not correlated with the major driving variables for the entire communities. These results demonstrate that soil archaea, bacteria, and fungi have different biogeographic patterns and driving processes along this continental-scale natural vegetation gradient, implying different community assembly mechanisms and ecological functions for archaea, bacteria, and fungi in soil ecosystems. IMPORTANCE Understanding biogeographic patterns is a precursor to improving our knowledge of the function of microbiomes and to predicting ecosystem responses to environmental change. Using natural forest soil samples from 110 locations, this study is one of the largest attempts to comprehensively understand the different patterns of soil archaeal, bacterial, and fungal biogeography at the continental scale in eastern China. These patterns in natural forest sites could ascertain reliable soil microbial biogeographic patterns by eliminating anthropogenic influences. This information provides guidelines for monitoring the belowground ecosystem's decline and restoration. Meanwhile, the deviations in the soil microbial communities from corresponding natural forest states indicate the extent of degradation of the soil ecosystem. Moreover, given the association between vegetation type and the microbial community, this information could be used to predict the long-term response of the underground ecosystem to the vegetation distribution caused by global climate change.},
}
@article {pmid28188879,
year = {2017},
author = {Jin, D and Kang, K and Wang, H and Wang, Z and Xue, B and Wang, L and Xu, F and Peng, Q},
title = {Effects of dietary supplementation of active dried yeast on fecal methanogenic archaea diversity in dairy cows.},
journal = {Anaerobe},
volume = {44},
number = {},
pages = {78-86},
doi = {10.1016/j.anaerobe.2017.02.007},
pmid = {28188879},
issn = {1095-8274},
mesh = {Animals ; Archaea/classification/genetics/*isolation &amp; purification/metabolism ; *Biodiversity ; Cattle ; Diet/*methods ; *Dietary Supplements ; Feces/*microbiology ; High-Throughput Nucleotide Sequencing ; Methane/*metabolism ; Real-Time Polymerase Chain Reaction ; Yeast, Dried/*administration &amp; dosage ; },
abstract = {This study aimed to investigate the effects of dietary supplementation of different dosages of active dried yeast (ADY) on the fecal methanogenic archaea community of dairy cattle. Twelve multiparous, healthy, mid-lactating Holstein dairy cows (body weight: 584 ± 23.2 kg, milk produced: 26.3 ± 1.22 kg/d) were randomly assigned to one of three treatments (control, ADY2, and ADY4) according to body weight with four replicates per treatment. Cows in the control group were fed conventional rations without ADY supplementation, while cows in the ADY2 and ADY4 group were fed rations supplemented with ADY at 2 or 4 g/d/head. Real-time PCR analysis showed the populations of total methanogens in the feces were significantly decreased (P < 0.05) in the ADY4 group compared with control. High-throughput sequencing technology was applied to examine the differences in methanogenic archaea diversity in the feces of the three treatment groups. A total of 155,609 sequences were recovered (a mean of 12,967 sequences per sample) from the twelve fecal samples, which consisted of a number of operational taxonomic units (OTUs) ranging from 1451 to 1,733, were assigned to two phyla, four classes, five orders, five families and six genera. Bioinformatic analyses illustrated that the natural fecal archaeal community of the control group was predominated by Methanobrevibacter (86.9% of the total sequence reads) and Methanocorpusculum (10.4%), while the relative abundance of the remaining four genera were below 1% with Methanosphaera comprising 0.8%, Thermoplasma composing 0.4%, and the relative abundance of Candidatus Nitrososphaera and Halalkalicoccus being close to zero. At the genus level, the relative abundances of Methanocorpusculum and Thermoplasma were increased (P < 0.05) with increasing dosage of ADY. Conversely, the predominant methanogen genus Methanobrevibacter was decreased with ADY dosage (P < 0.05). Dietary supplementation of ADY had no significant effect (P > 0.05) on the abundances of genera unclassified, Candidatus Nitrososphaera, and Halalkalicoccus. In conclusion, supplementation of ADY to the rations of dairy cattle could alter the population sizes and composition of fecal methanogenic archaea in the feces of dairy cattle. The decrease in Methanobrevibacter happened with a commensurate increase in the genera Methanocorpusculum and Thermoplasma.},
}
@article {pmid28177649,
year = {2017},
author = {Thomas, L and Ram, H and Singh, VP},
title = {Evolutionary Relationships and Taxa-Specific Conserved Signature Indels Among Cellulases of Archaea, Bacteria, and Eukarya.},
journal = {Journal of computational biology : a journal of computational molecular cell biology},
volume = {24},
number = {10},
pages = {1029-1042},
doi = {10.1089/cmb.2016.0161},
pmid = {28177649},
issn = {1557-8666},
mesh = {Archaea/classification/*enzymology/genetics ; Bacteria/classification/*enzymology/genetics ; Cellulases/*genetics ; Eukaryota/classification/*enzymology/genetics ; *Evolution, Molecular ; *INDEL Mutation ; Phylogeny ; Substrate Specificity ; },
abstract = {The cellulases from different cellulolytic organisms have evolutionary relationships, which range from single-celled prokaryotes to the complex eukaryotes of the living world. This in silico analysis revealed the presence of a conserved cellulase domain along with evolutionary relationships among cellulases from several species of Archaea, Bacteria, and Eukarya. The amino acid sequences of cellulases from Archaea and Bacteria showed closer identity with their domain or phylum members that provided insights into convergent and divergent evolution of cellulases from other enzymes with different substrate specificities. Evolutionary relatedness was also observed in phylogenetic trees among a number of cellulase sequences of diverse taxa. In cellulases, propensity for alanine, glycine, leucine, serine, and threonine was high, but low for cysteine, histidine, and methionine. Catalytic aspartic acid had a higher propensity than glutamic acid, and both were involved in regular expression patterns. Characteristic group and multigroup-specific conserved signature indels located in the catalytic domains of cellulases were observed that further clarified evolutionary relationships. These indels can be distinctive molecular tools for understanding phylogeny and identification of unknown cellulolytic species of common evolutionary descent in different environments.},
}
@article {pmid28174314,
year = {2017},
author = {Yan, Z and Wang, M and Ferry, JG},
title = {A Ferredoxin- and F420H2-Dependent, Electron-Bifurcating, Heterodisulfide Reductase with Homologs in the Domains Bacteria and Archaea.},
journal = {mBio},
volume = {8},
number = {1},
pages = {},
pmid = {28174314},
issn = {2150-7511},
mesh = {Anaerobiosis ; Electron Transport ; Escherichia coli/genetics/*metabolism ; Ferredoxins/*metabolism ; Gene Expression ; Methane/metabolism ; Methanosarcina/*enzymology/genetics ; Oxidation-Reduction ; Oxidoreductases/*genetics/*metabolism ; Riboflavin/*analogs &amp; derivatives/metabolism ; Sequence Homology ; },
abstract = {Heterodisulfide reductases (Hdr) of the HdrABC class are ancient enzymes and a component of the anaerobic core belonging to the prokaryotic common ancestor. The ancient origin is consistent with the widespread occurrence of genes encoding putative HdrABC homologs in metabolically diverse prokaryotes predicting diverse physiological functions; however, only one HdrABC has been characterized and that was from a narrow metabolic group of obligate CO2-reducing methanogenic anaerobes (methanogens) from the domain Archaea Here we report the biochemical characterization of an HdrABC homolog (HdrA2B2C2) from the acetate-utilizing methanogen Methanosarcina acetivorans with unusual properties structurally and functionally distinct from the only other HdrABC characterized. Homologs of the HdrA2B2C2 archetype are present in phylogenetically and metabolically diverse species from the domains Bacteria and Archaea The expression of the individual HdrA2, HdrB2, and HdrB2C2 enzymes in Escherichia coli, and reconstitution of an active HdrA2B2C2 complex, revealed an intersubunit electron transport pathway dependent on ferredoxin or coenzyme F420 (F420H2) as an electron donor. Remarkably, HdrA2B2C2 couples the previously unknown endergonic oxidation of F420H2 and reduction of ferredoxin with the exergonic oxidation of F420H2 and reduction of the heterodisulfide of coenzyme M and coenzyme B (CoMS-SCoB). The unique electron bifurcation predicts a role for HdrA2B2C2 in Fe(III)-dependent anaerobic methane oxidation (ANME) by M. acetivorans and uncultured species from ANME environments. HdrA2B2C2, ubiquitous in acetotrophic methanogens, was shown to participate in electron transfer during acetotrophic growth of M. acetivorans and proposed to be essential for growth in the environment when acetate is limiting.<br><br>IMPORTANCE: Discovery of the archetype HdrA2B2C2 heterodisulfide reductase with categorically unique properties extends the understanding of this ancient family beyond CO2-reducing methanogens to include diverse prokaryotes from the domains Bacteria and Archaea The unprecedented coenzyme F420-dependent electron bifurcation, an emerging fundamental principle of energy conservation, predicts a role for HdrA2B2C2 in diverse metabolisms, including anaerobic CH4-oxidizing pathways. The results document an electron transport role for HdrA2B2C2 in acetate-utilizing methanogens responsible for at least two-thirds of the methane produced in Earth's biosphere. The previously unavailable heterologous production of individual subunits and the reconstitution of HdrA2B2C2 with activity have provided an understanding of intersubunit electron transfer in the HdrABC class and a platform for investigating the principles of electron bifurcation.},
}
@article {pmid28168565,
year = {2017},
author = {Rosselló-Móra, R and Trujillo, ME and Sutcliffe, IC},
title = {Introducing a digital protologue: a timely move towards a database-driven systematics of archaea and bacteria.},
journal = {Antonie van Leeuwenhoek},
volume = {110},
number = {4},
pages = {455-456},
doi = {10.1007/s10482-017-0841-7},
pmid = {28168565},
issn = {1572-9699},
mesh = {Archaea/*classification/genetics ; Bacteria/*classification/genetics ; Classification/*methods ; Databases as Topic ; Phylogeny ; },
}
@article {pmid28154498,
year = {2017},
author = {Timmers, PH and Welte, CU and Koehorst, JJ and Plugge, CM and Jetten, MS and Stams, AJ},
title = {Reverse Methanogenesis and Respiration in Methanotrophic Archaea.},
journal = {Archaea (Vancouver, B.C.)},
volume = {2017},
number = {},
pages = {1654237},
pmid = {28154498},
issn = {1472-3654},
mesh = {Anaerobiosis ; Archaea/*metabolism ; Methane/*metabolism ; Oxidation-Reduction ; },
abstract = {Anaerobic oxidation of methane (AOM) is catalyzed by anaerobic methane-oxidizing archaea (ANME) via a reverse and modified methanogenesis pathway. Methanogens can also reverse the methanogenesis pathway to oxidize methane, but only during net methane production (i.e., &quot;trace methane oxidation&quot;). In turn, ANME can produce methane, but only during net methane oxidation (i.e., enzymatic back flux). Net AOM is exergonic when coupled to an external electron acceptor such as sulfate (ANME-1, ANME-2abc, and ANME-3), nitrate (ANME-2d), or metal (oxides). In this review, the reversibility of the methanogenesis pathway and essential differences between ANME and methanogens are described by combining published information with domain based (meta)genome comparison of archaeal methanotrophs and selected archaea. These differences include abundances and special structure of methyl coenzyme M reductase and of multiheme cytochromes and the presence of menaquinones or methanophenazines. ANME-2a and ANME-2d can use electron acceptors other than sulfate or nitrate for AOM, respectively. Environmental studies suggest that ANME-2d are also involved in sulfate-dependent AOM. ANME-1 seem to use a different mechanism for disposal of electrons and possibly are less versatile in electron acceptors use than ANME-2. Future research will shed light on the molecular basis of reversal of the methanogenic pathway and electron transfer in different ANME types.},
}
@article {pmid28146124,
year = {2017},
author = {Ausiannikava, D and Allers, T},
title = {Diversity of DNA Replication in the Archaea.},
journal = {Genes},
volume = {8},
number = {2},
pages = {},
pmid = {28146124},
issn = {2073-4425},
abstract = {DNA replication is arguably the most fundamental biological process. On account of their shared evolutionary ancestry, the replication machinery found in archaea is similar to that found in eukaryotes. DNA replication is initiated at origins and is highly conserved in eukaryotes, but our limited understanding of archaea has uncovered a wide diversity of replication initiation mechanisms. Archaeal origins are sequence-based, as in bacteria, but are bound by initiator proteins that share homology with the eukaryotic origin recognition complex subunit Orc1 and helicase loader Cdc6). Unlike bacteria, archaea may have multiple origins per chromosome and multiple Orc1/Cdc6 initiator proteins. There is no consensus on how these archaeal origins are recognised- some are bound by a single Orc1/Cdc6 protein while others require a multi- Orc1/Cdc6 complex. Many archaeal genomes consist of multiple parts-the main chromosome plus several megaplasmids-and in polyploid species these parts are present in multiple copies. This poses a challenge to the regulation of DNA replication. However, one archaeal species (Haloferax volcanii) can survive without replication origins; instead, it uses homologous recombination as an alternative mechanism of initiation. This diversity in DNA replication initiation is all the more remarkable for having been discovered in only three groups of archaea where in vivo studies are possible.},
}
@article {pmid28140393,
year = {2017},
author = {Mamet, SD and Lamb, EG and Piper, CL and Winsley, T and Siciliano, SD},
title = {Archaea and bacteria mediate the effects of native species root loss on fungi during plant invasion.},
journal = {The ISME journal},
volume = {11},
number = {5},
pages = {1261-1275},
pmid = {28140393},
issn = {1751-7370},
mesh = {Archaea/classification/*isolation &amp; purification ; Bacteria/classification/*isolation &amp; purification ; Biodiversity ; Bromus/microbiology ; Fungi/classification/*isolation &amp; purification ; Introduced Species ; Microbial Interactions ; Plant Roots/*microbiology ; *Soil Microbiology ; },
abstract = {Although invasive plants can drive ecosystem change, little is known about the directional nature of belowground interactions between invasive plants, native roots, bacteria, archaea and fungi. We used detailed bioinformatics and a recently developed root assay on soils collected in fescue grassland along a gradient of smooth brome (Bromus inermis Leyss) invasion to examine the links between smooth brome shoot litter and root, archaea, bacteria and fungal communities. We examined (1) aboveground versus belowground influences of smooth brome on soil microbial communities, (2) the importance of direct versus microbe-mediated impacts of plants on soil fungal communities, and (3) the web of roots, shoots, archaea, bacteria and fungi interactions across the A and B soil horizons in invaded and non-invaded sites. Archaea and bacteria influenced fungal composition, but not vice versa, as indicated by redundancy analyses. Co-inertia analyses suggested that bacterial-fungal variance was driven primarily by 12 bacterial operational taxonomic units (OTUs). Brome increased bacterial diversity via smooth brome litter in the A horizon and roots in the B horizon, which then reduced fungal diversity. Archaea increased abundance of several bacterial OTUs, and the key bacterial OTUs mediated changes in the fungi's response to invasion. Overall, native root diversity loss and bacterial mediation were more important drivers of fungal composition than were the direct effects of increases in smooth brome. Critically, native plant species displacement and root loss appeared to be the most important driver of fungal composition during invasion. This causal web likely gives rise to the plant-fungi feedbacks, which are an essential factor determining plant diversity in invaded grassland ecosystems.},
}
@article {pmid28133437,
year = {2017},
author = {Thor, S and Peterson, JR and Luthey-Schulten, Z},
title = {Genome-Scale Metabolic Modeling of Archaea Lends Insight into Diversity of Metabolic Function.},
journal = {Archaea (Vancouver, B.C.)},
volume = {2017},
number = {},
pages = {9763848},
pmid = {28133437},
issn = {1472-3654},
mesh = {Computational Biology ; Euryarchaeota/*metabolism ; *Metabolic Networks and Pathways ; *Models, Biological ; },
abstract = {Decades of biochemical, bioinformatic, and sequencing data are currently being systematically compiled into genome-scale metabolic reconstructions (GEMs). Such reconstructions are knowledge-bases useful for engineering, modeling, and comparative analysis. Here we review the fifteen GEMs of archaeal species that have been constructed to date. They represent primarily members of the Euryarchaeota with three-quarters comprising representative of methanogens. Unlike other reviews on GEMs, we specially focus on archaea. We briefly review the GEM construction process and the genealogy of the archaeal models. The major insights gained during the construction of these models are then reviewed with specific focus on novel metabolic pathway predictions and growth characteristics. Metabolic pathway usage is discussed in the context of the composition of each organism's biomass and their specific energy and growth requirements. We show how the metabolic models can be used to study the evolution of metabolism in archaea. Conservation of particular metabolic pathways can be studied by comparing reactions using the genes associated with their enzymes. This demonstrates the utility of GEMs to evolutionary studies, far beyond their original purpose of metabolic modeling; however, much needs to be done before archaeal models are as extensively complete as those for bacteria.},
}
@article {pmid28115203,
year = {2017},
author = {Michel, CJ},
title = {WITHDRAWN: The maximal C3 self-complementary trinucleotide circular code X in genes of bacteria, archaea, eukaryotes, plasmids and viruses.},
journal = {Journal of theoretical biology},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.jtbi.2017.01.028},
pmid = {28115203},
issn = {1095-8541},
}
@article {pmid28104666,
year = {2017},
author = {Buongiorno, J and Turner, S and Webster, G and Asai, M and Shumaker, AK and Roy, T and Weightman, A and Schippers, A and Lloyd, KG},
title = {Interlaboratory quantification of Bacteria and Archaea in deeply buried sediments of the Baltic Sea (IODP Expedition 347).},
journal = {FEMS microbiology ecology},
volume = {93},
number = {3},
pages = {},
doi = {10.1093/femsec/fix007},
pmid = {28104666},
issn = {1574-6941},
mesh = {Archaea/*genetics/growth &amp; development ; Bacteria/*genetics/growth &amp; development ; *Colony Count, Microbial ; DNA Primers ; Expeditions ; Geologic Sediments/*microbiology ; In Situ Hybridization, Fluorescence/methods ; Phylogeny ; RNA, Ribosomal, 16S/genetics ; Seawater/*microbiology ; *Water Microbiology ; },
abstract = {Two common quantification methods for subseafloor microorganisms are catalyzed reporter deposition fluorescence in situ hybridization (CARD-FISH) and quantitative PCR (qPCR). Using these methods, we quantified Bacteria and Archaea in Baltic Sea basin sediments (IODP Exp. 347) down to 90 mbsf, testing the following hypotheses in an interlaboratory comparison: (1) proteinase K permeabilization of archaeal cell walls increases CARD-FISH accuracy and (2) qPCR varies by more than an order of magnitude between laboratories using similar protocols. CARD-FISH counts did not differ between permeabilization treatments, demonstrating that proteinase K did not increase accuracy of CARD-FISH counts. However, 91% of these counts were below the quantification limit of 1.3 × 107 cells cm-3. For qPCR, data varied between laboratories, but were largely within the same order of magnitude if the same primers were used, with 88% of samples being above the quantification limit. Copy number values were elevated by preparing a sediment slurry before DNA extraction: 3.88 × 106-2.34 × 109 16S rRNA gene copies cm-3 vs. 1.39 × 107-1.87 × 109 total cells cm-3. By qPCR, Bacteria were more abundant than Archaea, although they usually were within the same order of magnitude. Overall, qPCR is more sensitive than CARD-FISH, but both require optimization to consistently achieve both precision and accuracy.},
}
@article {pmid28085154,
year = {2017},
author = {Lazar, CS and Baker, BJ and Seitz, KW and Teske, AP},
title = {Genomic reconstruction of multiple lineages of uncultured benthic archaea suggests distinct biogeochemical roles and ecological niches.},
journal = {The ISME journal},
volume = {11},
number = {5},
pages = {1118-1129},
pmid = {28085154},
issn = {1751-7370},
support = {247153//European Research Council/International ; },
mesh = {Acetyl Coenzyme A/metabolism ; Archaea/classification/*genetics/isolation &amp; purification/metabolism ; Carbon Cycle ; Ecosystem ; Estuaries ; *Genome, Archaeal ; Genomics ; Geologic Sediments/*microbiology ; Phylogeny ; Rivers ; },
abstract = {Genomic bins belonging to multiple archaeal lineages were recovered from distinct redox regimes in sediments of the White Oak River estuary. The reconstructed archaeal genomes were identified as belonging to the rice cluster subgroups III and V (RC-III, RC-V), the Marine Benthic Group D (MBG-D), and a newly described archaeal class, the Theionarchaea. The metabolic capabilities of these uncultured archaea were inferred and indicated a common capability for extracellular protein degradation, supplemented by other pathways. The multiple genomic bins within the MBG-D archaea shared a nearly complete reductive acetyl-CoA pathway suggesting acetogenic capabilities. In contrast, the RC-III metabolism appeared centered on the degradation of detrital proteins and production of H2, whereas the RC-V archaea lacked capabilities for protein degradation and uptake, and appeared to be specialized on carbohydrate fermentation. The Theionarchaea appeared as complex metabolic hybrids; encoding a complete tricarboxylic acid cycle permitting carbon (acetyl-CoA) oxidation, together with a complete reductive acetyl-CoA pathway and sulfur reduction by a sulfhydrogenase. The differentiated inferred capabilities of these uncultured archaeal lineages indicated lineage-specific linkages with the nitrogen, carbon and sulfur cycles. The predicted metabolisms of these archaea suggest preferences for distinct geochemical niches within the estuarine sedimentary environment.},
}
@article {pmid28082747,
year = {2017},
author = {Kono, T and Mehrotra, S and Endo, C and Kizu, N and Matusda, M and Kimura, H and Mizohata, E and Inoue, T and Hasunuma, T and Yokota, A and Matsumura, H and Ashida, H},
title = {A RuBisCO-mediated carbon metabolic pathway in methanogenic archaea.},
journal = {Nature communications},
volume = {8},
number = {},
pages = {14007},
pmid = {28082747},
issn = {2041-1723},
mesh = {Archaeal Proteins/chemistry/genetics/*metabolism ; Carbon/metabolism ; Euryarchaeota/classification/*enzymology/genetics/metabolism ; Metabolic Networks and Pathways ; Phosphotransferases (Alcohol Group Acceptor)/chemistry/genetics/metabolism ; Photosynthesis ; Phylogeny ; Ribulose-Bisphosphate Carboxylase/chemistry/genetics/*metabolism ; },
abstract = {Two enzymes are considered to be unique to the photosynthetic Calvin-Benson cycle: ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO), responsible for CO2 fixation, and phosphoribulokinase (PRK). Some archaea possess bona fide RuBisCOs, despite not being photosynthetic organisms, but are thought to lack PRK. Here we demonstrate the existence in methanogenic archaea of a carbon metabolic pathway involving RuBisCO and PRK, which we term 'reductive hexulose-phosphate' (RHP) pathway. These archaea possess both RuBisCO and a catalytically active PRK whose crystal structure resembles that of photosynthetic bacterial PRK. Capillary electrophoresis-mass spectrometric analysis of metabolites reveals that the RHP pathway, which differs from the Calvin-Benson cycle only in a few steps, is active in vivo. Our work highlights evolutionary and functional links between RuBisCO-mediated carbon metabolic pathways in methanogenic archaea and photosynthetic organisms. Whether the RHP pathway allows for autotrophy (that is, growth exclusively with CO2 as carbon source) remains unknown.},
}
@article {pmid28077874,
year = {2017},
author = {Zaremba-Niedzwiedzka, K and Caceres, EF and Saw, JH and Bäckström, D and Juzokaite, L and Vancaester, E and Seitz, KW and Anantharaman, K and Starnawski, P and Kjeldsen, KU and Stott, MB and Nunoura, T and Banfield, JF and Schramm, A and Baker, BJ and Spang, A and Ettema, TJ},
title = {Asgard archaea illuminate the origin of eukaryotic cellular complexity.},
journal = {Nature},
volume = {541},
number = {7637},
pages = {353-358},
pmid = {28077874},
issn = {1476-4687},
mesh = {Archaea/classification/*cytology/*genetics ; Archaeal Proteins/genetics/metabolism ; Biological Transport/genetics ; COP-Coated Vesicles/metabolism ; Eukaryota/classification/*cytology/genetics ; Eukaryotic Cells/classification/*cytology/metabolism ; *Evolution, Molecular ; Genome, Archaeal/*genetics ; Metagenomics ; *Models, Biological ; *Phylogeny ; },
abstract = {The origin and cellular complexity of eukaryotes represent a major enigma in biology. Current data support scenarios in which an archaeal host cell and an alphaproteobacterial (mitochondrial) endosymbiont merged together, resulting in the first eukaryotic cell. The host cell is related to Lokiarchaeota, an archaeal phylum with many eukaryotic features. The emergence of the structural complexity that characterizes eukaryotic cells remains unclear. Here we describe the 'Asgard' superphylum, a group of uncultivated archaea that, as well as Lokiarchaeota, includes Thor-, Odin- and Heimdallarchaeota. Asgard archaea affiliate with eukaryotes in phylogenomic analyses, and their genomes are enriched for proteins formerly considered specific to eukaryotes. Notably, thorarchaeal genomes encode several homologues of eukaryotic membrane-trafficking machinery components, including Sec23/24 and TRAPP domains. Furthermore, we identify thorarchaeal proteins with similar features to eukaryotic coat proteins involved in vesicle biogenesis. Our results expand the known repertoire of 'eukaryote-specific' proteins in Archaea, indicating that the archaeal host cell already contained many key components that govern eukaryotic cellular complexity.},
}
@article {pmid28073944,
year = {2017},
author = {Rodionova, IA and Vetting, MW and Li, X and Almo, SC and Osterman, AL and Rodionov, DA},
title = {A novel bifunctional transcriptional regulator of riboflavin metabolism in Archaea.},
journal = {Nucleic acids research},
volume = {45},
number = {7},
pages = {3785-3799},
pmid = {28073944},
issn = {1362-4962},
support = {P30 CA030199/CA/NCI NIH HHS/United States ; },
mesh = {Archaea/enzymology/*genetics/metabolism ; Archaeal Proteins/chemistry/*metabolism ; DNA, Archaeal/chemistry/metabolism ; Evolution, Molecular ; Genome, Archaeal ; Operator Regions, Genetic ; Phosphotransferases (Alcohol Group Acceptor)/chemistry/*metabolism ; Protein Domains ; Regulon ; Riboflavin/*metabolism ; Transcription Factors/chemistry/*metabolism ; },
abstract = {Riboflavin (vitamin B2) is the precursor of flavin mononucleotide (FMN) and flavin adenine dinucleotide, which are essential coenzymes in all free-living organisms. Riboflavin biosynthesis in many Bacteria but not in Archaea is controlled by FMN-responsive riboswitches. We identified a novel bifunctional riboflavin kinase/regulator (RbkR), which controls riboflavin biosynthesis and transport genes in major lineages of Crenarchaeota, Euryarchaeota and Thaumarchaeota. RbkR proteins are composed of the riboflavin kinase domain and a DNA-binding winged helix-turn-helix-like domain. Using comparative genomics, we predicted RbkR operator sites and reconstructed RbkR regulons in 94 archaeal genomes. While the identified RbkR operators showed significant variability between archaeal lineages, the conserved core of RbkR regulons includes riboflavin biosynthesis genes, known/predicted vitamin uptake transporters and the rbkR gene. The DNA motifs and CTP-dependent riboflavin kinase activity of two RbkR proteins were experimentally validated in vitro. The DNA binding activity of RbkR was stimulated by CTP and suppressed by FMN, a product of riboflavin kinase. The crystallographic structure of RbkR from Thermoplasma acidophilum was determined in complex with CTP and its DNA operator revealing key residues for operator and ligand recognition. Overall, this study contributes to our understanding of metabolic and regulatory networks for vitamin homeostasis in Archaea.},
}
@article {pmid28070167,
year = {2016},
author = {Ma, Y and Liu, F and Kong, Z and Yin, J and Kou, W and Wu, L and Ge, G},
title = {The Distribution Pattern of Sediment Archaea Community of the Poyang Lake, the Largest Freshwater Lake in China.},
journal = {Archaea (Vancouver, B.C.)},
volume = {2016},
number = {},
pages = {9278929},
pmid = {28070167},
issn = {1472-3654},
mesh = {Archaea/*classification/genetics ; *Biota ; China ; Cluster Analysis ; DNA, Archaeal/chemistry/genetics ; DNA, Ribosomal/chemistry/genetics ; Fresh Water/*microbiology ; Geologic Sediments/*microbiology ; Lakes/*microbiology ; Phylogeography ; RNA, Ribosomal, 16S/genetics ; Sequence Analysis, DNA ; Spatial Analysis ; },
abstract = {Archaea plays an important role in the global geobiochemical circulation of various environments. However, much less is known about the ecological role of archaea in freshwater lake sediments. Thus, investigating the structure and diversity of archaea community is vital to understand the metabolic processes in freshwater lake ecosystems. In this study, sediment physicochemical properties were combined with the results from 16S rRNA clone library-sequencing to examine the sediment archaea diversity and the environmental factors driving the sediment archaea community structures. Seven sites were chosen from Poyang Lake, including two sites from the main lake body and five sites from the inflow river estuaries. Our results revealed high diverse archaea community in the sediment of Poyang Lake, including Bathyarchaeota (45.5%), Euryarchaeota (43.1%), Woesearchaeota (3.6%), Pacearchaeota (1.7%), Thaumarchaeota (1.4%), suspended Lokiarchaeota (0.7%), Aigarchaeota (0.2%), and Unclassified Archaea (3.8%). The archaea community compositions differed among sites, and sediment property had considerable influence on archaea community structures and distribution, especially total organic carbon (TOC) and metal lead (Pb) (p < 0.05). This study provides primary profile of sediment archaea distribution in freshwater lakes and helps to deepen our understanding of lake sediment microbes.},
}
@article {pmid28053595,
year = {2016},
author = {Prunetti, L and Graf, M and Blaby, IK and Peil, L and Makkay, AM and Starosta, AL and Papke, RT and Oshima, T and Wilson, DN and de Crécy-Lagard, V},
title = {Deciphering the Translation Initiation Factor 5A Modification Pathway in Halophilic Archaea.},
journal = {Archaea (Vancouver, B.C.)},
volume = {2016},
number = {},
pages = {7316725},
pmid = {28053595},
issn = {1472-3654},
support = {R01 GM070641/GM/NIGMS NIH HHS/United States ; },
mesh = {Archaeal Proteins/*metabolism ; Chromatography, Liquid ; Haloferax volcanii/*enzymology/*metabolism ; Lysine/*analogs &amp; derivatives/metabolism ; Peptide Initiation Factors/*metabolism ; *Protein Processing, Post-Translational ; Tandem Mass Spectrometry ; },
abstract = {Translation initiation factor 5A (IF5A) is essential and highly conserved in Eukarya (eIF5A) and Archaea (aIF5A). The activity of IF5A requires hypusine, a posttranslational modification synthesized in Eukarya from the polyamine precursor spermidine. Intracellular polyamine analyses revealed that agmatine and cadaverine were the main polyamines produced in Haloferax volcanii in minimal medium, raising the question of how hypusine is synthesized in this halophilic Archaea. Metabolic reconstruction led to a tentative picture of polyamine metabolism and aIF5A modification in Hfx. volcanii that was experimentally tested. Analysis of aIF5A from Hfx. volcanii by LC-MS/MS revealed it was exclusively deoxyhypusinylated. Genetic studies confirmed the role of the predicted arginine decarboxylase gene (HVO_1958) in agmatine synthesis. The agmatinase-like gene (HVO_2299) was found to be essential, consistent with a role in aIF5A modification predicted by physical clustering evidence. Recombinant deoxyhypusine synthase (DHS) from S. cerevisiae was shown to transfer 4-aminobutyl moiety from spermidine to aIF5A from Hfx. volcanii in vitro. However, at least under conditions tested, this transfer was not observed with the Hfx. volcanii DHS. Furthermore, the growth of Hfx. volcanii was not inhibited by the classical DHS inhibitor GC7. We propose a model of deoxyhypusine synthesis in Hfx. volcanii that differs from the canonical eukaryotic pathway, paving the way for further studies.},
}
@article {pmid28029780,
year = {2017},
author = {Srivastava, SS and Jamkhindikar, AA and Raman, R and Jobby, MK and Chadalawada, S and Sankaranarayanan, R and Sharma, Y},
title = {A Transition Metal-Binding, Trimeric βγ-Crystallin from Methane-Producing Thermophilic Archaea, Methanosaeta thermophila.},
journal = {Biochemistry},
volume = {56},
number = {9},
pages = {1299-1310},
doi = {10.1021/acs.biochem.6b00985},
pmid = {28029780},
issn = {1520-4995},
mesh = {Archaea/*metabolism ; Methane/biosynthesis ; Models, Molecular ; *Protein Multimerization ; Protein Structure, Quaternary ; Temperature ; Transition Elements/*metabolism ; beta-Crystallins/*chemistry/*metabolism ; gamma-Crystallins/*chemistry/*metabolism ; },
abstract = {βγ-Crystallins are important constituents of the vertebrate eye lens, whereas in microbes, they are prevalent as Ca2+-binding proteins. In archaea, βγ-crystallins are conspicuously confined to two methanogens, viz., Methanosaeta and Methanosarcina. One of these, i.e., M-crystallin from Methanosarcina acetivorans, has been shown to be a typical Ca2+-binding βγ-crystallin. Here, with the aid of a high-resolution crystal structure and isothermal titration calorimetry, we report that &quot;Methallin&quot;, a βγ-crystallin from Methanosaeta thermophila, is a trimeric, transition metal-binding protein. It binds Fe, Ni, Co, or Zn ion with nanomolar affinity, which is consistent even at 55 °C, the optimal temperature for the methanogen's growth. At the center of the protein trimer, the metal ion is coordinated by six histidines, two from each protomer, leading to an octahedral geometry. Small-angle X-ray scattering analysis confirms that the trimer seen in the crystal lattice is a biological assembly; this assembly dissociates to monomers upon removal of the metal ion. The introduction of two histidines (S17H/S19H) into a homologous βγ-crystallin, Clostrillin, allows it to bind nickel at the introduced site, though with micromolar affinity. However, because of the lack of a compatible interface, nickel binding could not induce trimerization, affirming that Methallin is a naturally occurring trimer for high-affinity transition metal binding. While βγ-crystallins are known to bind Ca2+ and form homodimers and oligomers, the transition metal-binding, trimeric Methallin is a new paradigm for βγ-crystallins. The distinct features of Methallin, such as nickel or iron binding, are also possible imprints of biogeochemical changes during the period of its origin.},
}
@article {pmid28018603,
year = {2017},
author = {Khelaifia, S and Caputo, A and Djossou, F and Raoult, D},
title = {Draft genome sequence of a human-associated isolate of Haloferax alexandrinus strain Arc-hr, an extremely halophilic archaea.},
journal = {New microbes and new infections},
volume = {15},
number = {},
pages = {44-45},
pmid = {28018603},
issn = {2052-2975},
abstract = {We report the draft genome sequence of Haloferax alexandrinus strain Arc-hr (CSUR P798), isolated from the human gut of a 10-year-old Amazonian individual. Its 3 893 626 bp genome exhibits a 66.00% GC content. The genome of the strain Arc-hr contains 37 genes identified as ORFans, seven genes associated to halocin and 11 genes associated with polyketide synthases or nonribosomal peptide synthetases.},
}
@article {pmid27998783,
year = {2017},
author = {Ding, J and Lu, YZ and Fu, L and Ding, ZW and Mu, Y and Cheng, SH and Zeng, RJ},
title = {Decoupling of DAMO archaea from DAMO bacteria in a methane-driven microbial fuel cell.},
journal = {Water research},
volume = {110},
number = {},
pages = {112-119},
doi = {10.1016/j.watres.2016.12.006},
pmid = {27998783},
issn = {1879-2448},
mesh = {Anaerobiosis ; Archaea/*genetics ; Bacteria/metabolism ; Bioelectric Energy Sources ; In Situ Hybridization, Fluorescence ; Methane/metabolism ; Methylococcaceae/*metabolism ; Oxidation-Reduction ; },
abstract = {Anaerobic oxidation of methane (AOM) contributes significantly to the global methane sink. Previously, studies of anaerobic methanotrophic (ANME) archaea have been limited as they have not been separable from their bacterial partners during the AOM process because of their dependence on the bacteria. A microbial fuel cell (MFC) is a device capable of directly transforming chemical energy to electrical energy via electrochemical reactions involving biochemical pathways. In this study, decoupling of denitrifying anaerobic methane oxidation (DAMO) archaea and DAMO bacteria was investigated in an microbial fuel cell (MFC) using methane as the fuel. The DAMO fuel cell worked successfully but demonstrated weak electrogenic capability with around 25 mV production. After 45 days' enrichment, the sequencing and fluorescence in situ hybridization results showed the DAMO archaea percentage had increased from 26.96% (inoculum) to 65.77% (electrode biofilm), while the DAMO bacteria percentage decreased from 24.39% to 2.07%. Moreover, the amount of ANME-2d had doubled in the electrode biofilm compared with the inoculum. The sequencing results also showed substantial enrichment of the Ignavibacterium and Geobacter genera. The roles of Ignavibacterium and Geobacter in the MFC system need to be further investigated. Nevertheless, these results illustrate that an MFC device may provide a possible approach to separate DAMO archaea from DAMO bacteria.},
}
@article {pmid27996979,
year = {2017},
author = {Taylor, AE and Giguere, AT and Zoebelein, CM and Myrold, DD and Bottomley, PJ},
title = {Modeling of soil nitrification responses to temperature reveals thermodynamic differences between ammonia-oxidizing activity of archaea and bacteria.},
journal = {The ISME journal},
volume = {11},
number = {4},
pages = {896-908},
pmid = {27996979},
issn = {1751-7370},
mesh = {Ammonia/chemistry/*metabolism ; Archaea/classification/*metabolism ; Bacteria/classification/*metabolism ; Nitrification ; Oregon ; Oxidation-Reduction ; Soil/*chemistry ; *Soil Microbiology ; Temperature ; },
abstract = {Soil nitrification potential (NP) activities of ammonia-oxidizing archaea and bacteria (AOA and AOB, respectively) were evaluated across a temperature gradient (4-42 °C) imposed upon eight soils from four different sites in Oregon and modeled with both the macromolecular rate theory and the square root growth models to quantify the thermodynamic responses. There were significant differences in response by the dominant AOA and AOB contributing to the NPs. The optimal temperatures (Topt) for AOA- and AOB-supported NPs were significantly different (P<0.001), with AOA having Topt>12 °C greater than AOB. The change in heat capacity associated with the temperature dependence of nitrification (ΔCP‡) was correlated with Topt across the eight soils, and the ΔCP‡ of AOB activity was significantly more negative than that of AOA activity (P<0.01). Model results predicted, and confirmatory experiments showed, a significantly lower minimum temperature (Tmin) and different, albeit very similar, maximum temperature (Tmax) values for AOB than for AOA activity. The results also suggested that there may be different forms of AOA AMO that are active over different temperature ranges with different Tmin, but no evidence of multiple Tmin values within the AOB. Fundamental differences in temperature-influenced properties of nitrification driven by AOA and AOB provides support for the idea that the biochemical processes associated with NH3 oxidation in AOA and AOB differ thermodynamically from each other, and that also might account for the difficulties encountered in attempting to model the response of nitrification to temperature change in soil environments.},
}
@article {pmid27984824,
year = {2017},
author = {Moukhtar, M and Chaar, W and Abdel-Razzak, Z and Khalil, M and Taha, S and Chamieh, H},
title = {ARCPHdb: A comprehensive protein database for SF1 and SF2 helicase from archaea.},
journal = {Computers in biology and medicine},
volume = {80},
number = {},
pages = {185-189},
doi = {10.1016/j.compbiomed.2016.12.004},
pmid = {27984824},
issn = {1879-0534},
mesh = {Archaea ; *Archaeal Proteins ; *Computational Biology ; Database Management Systems ; *Databases, Protein ; *RNA Helicases ; User-Computer Interface ; },
abstract = {PURPOSE: Superfamily 1 and Superfamily 2 helicases, two of the largest helicase protein families, play vital roles in many biological processes including replication, transcription and translation. Study of helicase proteins in the model microorganisms of archaea have largely contributed to the understanding of their function, architecture and assembly. Based on a large phylogenomics approach, we have identified and classified all SF1 and SF2 protein families in ninety five sequenced archaea genomes. Here we developed an online webserver linked to a specialized protein database named ARCPHdb to provide access for SF1 and SF2 helicase families from archaea.<br><br>METHODS: ARCPHdb was implemented using MySQL relational database. Web interfaces were developed using Netbeans. Data were stored according to UniProt accession numbers, NCBI Ref Seq ID, PDB IDs and Entrez Databases.<br><br>RESULTS: A user-friendly interactive web interface has been developed to browse, search and download archaeal helicase protein sequences, their available 3D structure models, and related documentation available in the literature provided by ARCPHdb. The database provides direct links to matching external databases.<br><br>CONCLUSIONS: The ARCPHdb is the first online database to compile all protein information on SF1 and SF2 helicase from archaea in one platform. This database provides essential resource information for all researchers interested in the field.},
}
@article {pmid27976411,
year = {2017},
author = {Paul, SS and Dey, A and Baro, D and Punia, BS},
title = {Comparative community structure of archaea in rumen of buffaloes and cattle.},
journal = {Journal of the science of food and agriculture},
volume = {97},
number = {10},
pages = {3284-3293},
doi = {10.1002/jsfa.8177},
pmid = {27976411},
issn = {1097-0010},
mesh = {Animals ; Archaea/classification/genetics/growth &amp; development/*isolation &amp; purification ; Buffaloes/*microbiology ; Cattle/*microbiology ; *Gastrointestinal Microbiome ; Phylogeny ; Rumen/*microbiology ; },
abstract = {BACKGROUND: Detailed knowledge of the community structure of methanogens is essential for amelioration of methane emission from livestock species. Several studies have indicated that predominant methanogens of buffalo rumen are different from those in cattle. However, predominant genera of methanogens reported by individual studies varied primarily because of limited scope of sampling, sequencing of limited number of sequences and potential PCR bias in individual studies. In this study, the collective comparative diversity of methanogenic archaea in the rumen of cattle and buffaloes was examined by performing a meta-analysis of all the 16S rRNA (rrn) sequences deposited in GenBank.<br><br>RESULTS: Ruminal methanogen sequences of buffalo were clustered into 900 species-level operational taxonomic units (OTUs), and ruminal methanogen sequences of cattle were clustered into 1522 species level OTUs. The number of species-level OTUs shared between cattle and buffaloes was 229 (10.4% of all OTUs), comprising 1746 sequences (27% of the total 6447 sequences). According to taxonomic classification by three different classifiers, Methanobrevibacter was found to be the most predominant genus both in cattle (69-71% of sequences) as well as buffaloes (65.1-68.9% of sequences). Percentage of Methanomicrobium was much higher (P < 0.05) in the case of buffalo (18%) than that of cattle (4.5%). On the other hand, percentages of Methanosphaera- and Methanomassiliicoccus-like methanogens were much higher (P < 0.05) in cattle than in buffaloes.<br><br>CONCLUSION: This study indicated that there is a substantial difference in community structure of ruminal methanogens of cattle and buffaloes. The study has also indicated that the percent of species-level operational taxonomic units shared between cattle and buffalo is very low, and thus host species-specific methane mitigation strategies need to be developed for cattle and buffaloes. © 2016 Society of Chemical Industry.},
}
@article {pmid27966672,
year = {2016},
author = {Golyshina, OV and Kublanov, IV and Tran, H and Korzhenkov, AA and Lünsdorf, H and Nechitaylo, TY and Gavrilov, SN and Toshchakov, SV and Golyshin, PN},
title = {Biology of archaea from a novel family Cuniculiplasmataceae (Thermoplasmata) ubiquitous in hyperacidic environments.},
journal = {Scientific reports},
volume = {6},
number = {},
pages = {39034},
pmid = {27966672},
issn = {2045-2322},
support = {BB/M029085/1//Biotechnology and Biological Sciences Research Council/United Kingdom ; },
mesh = {Acids/*chemistry ; Archaeal Proteins/genetics/metabolism ; California ; *Ecosystem ; Euryarchaeota/classification/*genetics/metabolism ; Genome, Archaeal/*genetics ; Genomics/methods ; Geography ; Hydrogen-Ion Concentration ; Microscopy, Electron ; Phylogeny ; RNA, Ribosomal, 16S/genetics ; Sequence Analysis, DNA ; Spain ; Thermoplasmales/*genetics/metabolism/ultrastructure ; United Kingdom ; },
abstract = {The order Thermoplasmatales (Euryarchaeota) is represented by the most acidophilic organisms known so far that are poorly amenable to cultivation. Earlier culture-independent studies in Iron Mountain (California) pointed at an abundant archaeal group, dubbed 'G-plasma'. We examined the genomes and physiology of two cultured representatives of a Family Cuniculiplasmataceae, recently isolated from acidic (pH 1-1.5) sites in Spain and UK that are 16S rRNA gene sequence-identical with 'G-plasma'. Organisms had largest genomes among Thermoplasmatales (1.87-1.94 Mbp), that shared 98.7-98.8% average nucleotide identities between themselves and 'G-plasma' and exhibited a high genome conservation even within their genomic islands, despite their remote geographical localisations. Facultatively anaerobic heterotrophs, they possess an ancestral form of A-type terminal oxygen reductase from a distinct parental clade. The lack of complete pathways for biosynthesis of histidine, valine, leucine, isoleucine, lysine and proline pre-determines the reliance on external sources of amino acids and hence the lifestyle of these organisms as scavengers of proteinaceous compounds from surrounding microbial community members. In contrast to earlier metagenomics-based assumptions, isolates were S-layer-deficient, non-motile, non-methylotrophic and devoid of iron-oxidation despite the abundance of methylotrophy substrates and ferrous iron in situ, which underlines the essentiality of experimental validation of bioinformatic predictions.},
}
@article {pmid27920295,
year = {2017},
author = {Rodionov, DA and Leyn, SA and Li, X and Rodionova, IA},
title = {A Novel Transcriptional Regulator Related to Thiamine Phosphate Synthase Controls Thiamine Metabolism Genes in Archaea.},
journal = {Journal of bacteriology},
volume = {199},
number = {4},
pages = {},
pmid = {27920295},
issn = {1098-5530},
mesh = {Alkyl and Aryl Transferases/genetics/*metabolism ; Archaea/*enzymology/genetics/metabolism ; Computational Biology ; Gene Expression Regulation, Archaeal/*physiology ; Gene Expression Regulation, Enzymologic/*physiology ; Genome, Archaeal/genetics ; Genomics ; Thiamine/*metabolism ; Thiamine Pyrophosphate/*metabolism ; },
abstract = {Thiamine (vitamin B1) is a precursor of thiamine pyrophosphate (TPP), an essential coenzyme in the central metabolism of all living organisms. Bacterial thiamine biosynthesis and salvage genes are controlled at the RNA level by TPP-responsive riboswitches. In Archaea, TPP riboswitches are restricted to the Thermoplasmatales order. Mechanisms of transcriptional control of thiamine genes in other archaeal lineages remain unknown. Using the comparative genomics approach, we identified a novel family of transcriptional regulators (named ThiR) controlling thiamine biosynthesis and transport genes in diverse lineages in the Crenarchaeota phylum as well as in the Halobacteria and Thermococci classes of the Euryarchaeota ThiR regulators are composed of an N-terminal DNA-binding domain and a C-terminal ligand-binding domain, which is similar to the archaeal thiamine phosphate synthase ThiN. By using comparative genomics, we predicted ThiR-binding DNA motifs and reconstructed ThiR regulons in 67 genomes representing all above-mentioned lineages. The predicted ThiR-binding motifs are characterized by palindromic symmetry with several distinct lineage-specific consensus sequences. In addition to thiamine biosynthesis genes, the reconstructed ThiR regulons include various transporters for thiamine and its precursors. Bioinformatics predictions were experimentally validated by in vitro DNA-binding assays with the recombinant ThiR protein from the hyperthermophilic archaeon Metallosphaera yellowstonensis MK1. Thiamine phosphate and, to some extent, TPP and hydroxyethylthiazole phosphate were required for the binding of ThiR to its DNA targets, suggesting that ThiR is derepressed by limitation of thiamine phosphates. The thiamine phosphate-binding residues previously identified in ThiN are highly conserved in ThiR regulators, suggesting a conserved mechanism for effector recognition.<br><br>IMPORTANCE: Thiamine pyrophosphate is a cofactor for many essential enzymes for glucose and energy metabolism. Thiamine or vitamin B1 biosynthesis and its transcriptional regulation in Archaea are poorly understood. We applied the comparative genomics approach to identify a novel family of regulators for the transcriptional control of thiamine metabolism genes in Archaea and reconstructed the respective regulons. The predicted ThiR regulons in archaeal genomes control the majority of thiamine biosynthesis genes. The reconstructed regulon content suggests that numerous uptake transporters for thiamine and/or its precursors are encoded in archaeal genomes. The ThiR regulon was experimentally validated by DNA-binding assays with Metallosphaera spp. These discoveries contribute to our understanding of metabolic and regulatory networks involved in vitamin homeostasis in diverse lineages of Archaea.},
}
@article {pmid27919704,
year = {2017},
author = {Kurt-Kızıldoğan, A and Abanoz, B and Okay, S},
title = {Global transcriptome analysis of Halolamina sp. to decipher the salt tolerance in extremely halophilic archaea.},
journal = {Gene},
volume = {601},
number = {},
pages = {56-64},
doi = {10.1016/j.gene.2016.11.042},
pmid = {27919704},
issn = {1879-0038},
mesh = {Archaeal Proteins/genetics/metabolism ; Gene Expression Profiling ; Gene Expression Regulation, Archaeal ; Genome, Archaeal ; Halobacteriales/*genetics/isolation &amp; purification/*metabolism ; RNA, Archaeal/genetics ; Salinity ; Salt Tolerance/*genetics ; Sequence Analysis, RNA ; Transcriptome ; },
abstract = {Extremely halophilic archaea survive in the hypersaline environments such as salt lakes or salt mines. Therefore, these microorganisms are good sources to investigate the molecular mechanisms underlying the tolerance to high salt concentrations. In this study, a global transcriptome analysis was conducted in an extremely halophilic archaeon, Halolamina sp. YKT1, isolated from a salt mine in Turkey. A comparative RNA-seq analysis was performed using YKT1 isolate grown either at 2.7M NaCl or 5.5M NaCl concentrations. A total of 2149 genes were predicted to be up-regulated and 1638 genes were down-regulated in the presence of 5.5M NaCl. The salt tolerance of Halolamina sp. YKT1 involves the up-regulation of genes related with membrane transporters, CRISPR-Cas systems, osmoprotectant solutes, oxidative stress proteins, and iron metabolism. On the other hand, the genes encoding the proteins involved in DNA replication, transcription, translation, mismatch and nucleotide excision repair were down-regulated. The RNA-seq data were verified for seven up-regulated genes as well as six down-regulated genes via qRT-PCR analysis. This comprehensive transcriptome analysis showed that the halophilic archaeon canalizes its energy towards keeping the intracellular osmotic balance minimizing the production of nucleic acids and peptides.},
}
@article {pmid27879020,
year = {2017},
author = {Kuhn, A and Kiefer, D},
title = {Membrane protein insertase YidC in bacteria and archaea.},
journal = {Molecular microbiology},
volume = {103},
number = {4},
pages = {590-594},
doi = {10.1111/mmi.13586},
pmid = {27879020},
issn = {1365-2958},
mesh = {Cell Membrane/metabolism ; Escherichia coli/genetics/*metabolism ; Escherichia coli Proteins/genetics/*metabolism ; *Hydrophobic and Hydrophilic Interactions ; Membrane Transport Proteins/genetics/*metabolism ; Methanocaldococcus/genetics/*metabolism ; SEC Translocation Channels/genetics ; },
abstract = {The insertion of proteins into the prokaryotic plasma membrane is catalyzed by translocases and insertases. On one hand, the Sec translocase operates as a transmembrane channel that can open laterally to first bind and then release the hydrophobic segments of a substrate protein into the lipid bilayer. On the other hand, YidC insertases interact with their substrates in a groove-like structure at an amphiphilic protein-lipid interface thus allowing the transmembrane segments of the substrate to slide into the lipid bilayer. The recently published high-resolution structures of YidC provide new mechanistic insights of how transmembrane proteins achieve the transition from an aqueous environment in the cytoplasm to the hydrophobic lipid bilayer environment of the membrane.},
}
@article {pmid27864137,
year = {2017},
author = {Bharathi, M and Chellapandi, P},
title = {Intergenomic evolution and metabolic cross-talk between rumen and thermophilic autotrophic methanogenic archaea.},
journal = {Molecular phylogenetics and evolution},
volume = {107},
number = {},
pages = {293-304},
doi = {10.1016/j.ympev.2016.11.008},
pmid = {27864137},
issn = {1095-9513},
mesh = {Animals ; Archaea/*genetics ; *Autotrophic Processes ; DNA Replication/genetics ; *Evolution, Molecular ; Genetic Markers ; Genetic Variation ; *Genome, Archaeal ; Metabolic Networks and Pathways/genetics ; Methane/*metabolism ; Methanobacteriaceae/genetics ; Phylogeny ; Rumen/*microbiology ; Synteny ; },
abstract = {Methanobrevibacter ruminantium M1 (MRU) is a rumen methanogenic archaean that can be able to utilize formate and CO2/H2 as growth substrates. Extensive analysis on the evolutionary genomic contexts considered herein to unravel its intergenomic relationship and metabolic adjustment acquired from the genomic content of Methanothermobacter thermautotrophicus ΔH. We demonstrated its intergenomic distance, genome function, synteny homologs and gene families, origin of replication, and methanogenesis to reveal the evolutionary relationships between Methanobrevibacter and Methanothermobacter. Comparison of the phylogenetic and metabolic markers was suggested for its archaeal metabolic core lineage that might have evolved from Methanothermobacter. Orthologous genes involved in its hydrogenotrophic methanogenesis might be acquired from intergenomic ancestry of Methanothermobacter via Methanobacterium formicicum. Formate dehydrogenase (fdhAB) coding gene cluster and carbon monoxide dehydrogenase (cooF) coding gene might have evolved from duplication events within Methanobrevibacter-Methanothermobacter lineage, and fdhCD gene cluster acquired from bacterial origins. Genome-wide metabolic survey found the existence of four novel pathways viz. l-tyrosine catabolism, mevalonate pathway II, acyl-carrier protein metabolism II and glutathione redox reactions II in MRU. Finding of these pathways suggested that MRU has shown a metabolic potential to tolerate molecular oxygen, antimicrobial metabolite biosynthesis and atypical lipid composition in cell wall, which was acquainted by metabolic cross-talk with mammalian bacterial origins. We conclude that coevolution of genomic contents between Methanobrevibacter and Methanothermobacter provides a clue to understand the metabolic adaptation of MRU in the rumen at different environmental niches.},
}
@article {pmid27852927,
year = {2016},
author = {Urbonavičius, J and Rutkienė, R and Lopato, A and Tauraitė, D and Stankevičiūtė, J and Aučynaitė, A and Kaliniene, L and van Tilbeurgh, H and Meškys, R},
title = {Evolution of tRNAPhe:imG2 methyltransferases involved in the biosynthesis of wyosine derivatives in Archaea.},
journal = {RNA (New York, N.Y.)},
volume = {22},
number = {12},
pages = {1871-1883},
pmid = {27852927},
issn = {1469-9001},
mesh = {Amino Acid Sequence ; Archaea/*metabolism ; Guanosine/*analogs &amp; derivatives/biosynthesis ; Methyltransferases/chemistry/*metabolism ; RNA, Transfer, Phe/chemistry/*metabolism ; Sequence Homology, Amino Acid ; },
abstract = {Tricyclic wyosine derivatives are found at position 37 of eukaryotic and archaeal tRNAPhe In Archaea, the intermediate imG-14 is targeted by three different enzymes that catalyze the formation of yW-86, imG, and imG2. We have suggested previously that a peculiar methyltransferase (aTrm5a/Taw22) likely catalyzes two distinct reactions: N1-methylation of guanosine to yield m1G; and C7-methylation of imG-14 to yield imG2. Here we show that the recombinant aTrm5a/Taw22-like enzymes from both Pyrococcus abyssi and Nanoarchaeum equitans indeed possess such dual specificity. We also show that substitutions of individual conservative amino acids of P. abyssi Taw22 (P260N, E173A, and R174A) have a differential effect on the formation of m1G/imG2, while replacement of R134, F165, E213, and P262 with alanine abolishes the formation of both derivatives of G37. We further demonstrate that aTrm5a-type enzyme SSO2439 from Sulfolobus solfataricus, which has no N1-methyltransferase activity, exhibits C7-methyltransferase activity, thereby producing imG2 from imG-14. We thus suggest renaming such aTrm5a methyltransferases as Taw21 to distinguish between monofunctional and bifunctional aTrm5a enzymes.},
}
@article {pmid27846569,
year = {2016},
author = {Zheng, K and Ngo, PD and Owens, VL and Yang, XP and Mansoorabadi, SO},
title = {The biosynthetic pathway of coenzyme F430 in methanogenic and methanotrophic archaea.},
journal = {Science (New York, N.Y.)},
volume = {354},
number = {6310},
pages = {339-342},
doi = {10.1126/science.aag2947},
pmid = {27846569},
issn = {1095-9203},
mesh = {Amides/metabolism ; Archaeal Proteins/genetics/*metabolism ; Biosynthetic Pathways ; Genes, Archaeal ; Genetic Loci ; Genomics ; Metalloporphyrins/genetics/*metabolism ; Methane/*metabolism ; Methanosarcina/*enzymology/genetics ; Nickel/metabolism ; Oxidoreductases/genetics/*metabolism ; Uroporphyrins/*metabolism ; },
abstract = {Methyl-coenzyme M reductase (MCR) is the key enzyme of methanogenesis and anaerobic methane oxidation. The activity of MCR is dependent on the unique nickel-containing tetrapyrrole known as coenzyme F430. We used comparative genomics to identify the coenzyme F430 biosynthesis (cfb) genes and characterized the encoded enzymes from Methanosarcina acetivorans C2A. The pathway involves nickelochelation by a nickel-specific chelatase, followed by amidation to form Ni-sirohydrochlorin a,c-diamide. Next, a primitive homolog of nitrogenase mediates a six-electron reduction and γ-lactamization reaction before a Mur ligase homolog forms the six-membered carbocyclic ring in the final step of the pathway. These data show that coenzyme F430 can be synthesized from sirohydrochlorin using Cfb enzymes produced heterologously in a nonmethanogen host and identify several targets for inhibitors of biological methane formation.},
}
@article {pmid27829818,
year = {2016},
author = {Rodrigues, T and Belmok, A and Catão, E and Kyaw, CM},
title = {Archaea in Natural and Impacted Brazilian Environments.},
journal = {Archaea (Vancouver, B.C.)},
volume = {2016},
number = {},
pages = {1259608},
pmid = {27829818},
issn = {1472-3654},
mesh = {Archaea/*classification/*isolation &amp; purification ; *Biodiversity ; Brazil ; *Environmental Microbiology ; },
abstract = {In recent years, archaeal diversity surveys have received increasing attention. Brazil is a country known for its natural diversity and variety of biomes, which makes it an interesting sampling site for such studies. However, archaeal communities in natural and impacted Brazilian environments have only recently been investigated. In this review, based on a search on the PubMed database on the last week of April 2016, we present and discuss the results obtained in the 51 studies retrieved, focusing on archaeal communities in water, sediments, and soils of different Brazilian environments. We concluded that, in spite of its vast territory and biomes, the number of publications focusing on archaeal detection and/or characterization in Brazil is still incipient, indicating that these environments still represent a great potential to be explored.},
}
@article {pmid27815273,
year = {2017},
author = {Ballen-Segura, M and Felip, M and Catalan, J},
title = {Some Mixotrophic Flagellate Species Selectively Graze on Archaea.},
journal = {Applied and environmental microbiology},
volume = {83},
number = {2},
pages = {},
pmid = {27815273},
issn = {1098-5336},
mesh = {*Archaea ; *Bacteria ; Chrysophyta/*physiology ; Cryptophyta/*physiology ; *Food Chain ; In Situ Hybridization, Fluorescence ; Lakes/microbiology ; Plankton/*physiology ; Spain ; },
abstract = {Many phototrophic flagellates ingest prokaryotes. This mixotrophic trait becomes a critical aspect of the microbial loop in planktonic food webs because of the typical high abundance of these flagellates. Our knowledge of their selective feeding upon different groups of prokaryotes, particularly under field conditions, is still quite limited. In this study, we investigated the feeding behavior of three species (Rhodomonas sp., Cryptomonas ovata, and Dinobryon cylindricum) via their food vacuole content in field populations of a high mountain lake. We used the catalyzed reporter deposition-fluorescence in situ hybridization (CARD-FISH) protocol with probes specific for the domain Archaea and three groups of Eubacteria: Betaproteobacteria, Actinobacteria, and Cytophaga-Flavobacteria of Bacteroidetes Our results provide field evidence that contrasting selective feeding exists between coexisting mixotrophic flagellates under the same environmental conditions and that some prokaryotic groups may be preferentially impacted by phagotrophic pressure in aquatic microbial food webs. In our study, Archaea were the preferred prey, chiefly in the case of Rhodomonas sp., which rarely fed on any other prokaryotic group. In general, prey selection did not relate to prey size among the grazed groups. However, Actinobacteria, which were clearly avoided, mostly showed a size of <0.5 μm, markedly smaller than cells from the other groups.<br><br>IMPORTANCE: That mixotrophic flagellates are not randomly feeding in the main prokaryotic groups under field conditions is a pioneer finding in species-specific behavior that paves the way for future studies according to this new paradigm. The particular case that Archaea were preferentially affected in the situation studied shows that phagotrophic pressure cannot be disregarded when considering the distribution of this group in freshwater oligotrophic systems.},
}
@article {pmid27810876,
year = {2017},
author = {Miragoli, F and Federici, S and Ferrari, S and Minuti, A and Rebecchi, A and Bruzzese, E and Buccigrossi, V and Guarino, A and Callegari, ML},
title = {Impact of cystic fibrosis disease on archaea and bacteria composition of gut microbiota.},
journal = {FEMS microbiology ecology},
volume = {93},
number = {2},
pages = {},
pmid = {27810876},
issn = {1574-6941},
mesh = {Adolescent ; Adult ; Archaea/classification/genetics ; Bacteria/classification/genetics ; *Biodiversity ; Child ; Colon ; Cystic Fibrosis/*microbiology ; Euryarchaeota/genetics ; Feces/microbiology ; Female ; *Gastrointestinal Microbiome ; Humans ; Intestines/*microbiology/physiopathology ; Male ; Microbiota/genetics ; Real-Time Polymerase Chain Reaction ; Young Adult ; },
abstract = {Cystic fibrosis is often associated with intestinal inflammation due to several factors, including altered gut microbiota composition. In this study, we analyzed the fecal microbiota among patients with cystic fibrosis of 10-22 years of age, and compared the findings with age-matched healthy subjects. The participating patients included 14 homozygotes and 14 heterozygotes with the delF508 mutation, and 2 heterozygotes presenting non-delF508 mutations. We used PCR-DGGE and qPCR to analyze the presence of bacteria, archaea and sulfate-reducing bacteria. Overall, our findings confirmed disruption of the cystic fibrosis gut microbiota. Principal component analysis of the qPCR data revealed no differences between homozygotes and heterozygotes, while both groups were distinct from healthy subjects who showed higher biodiversity. Archaea were under the detection limit in all homozygotes subjects, whereas methanogens were detected in 62% of both cystic fibrosis heterozygotes and healthy subjects. Our qPCR results revealed a low frequency of sulfate-reducing bacteria in the homozygote (13%) and heterozygote (13%) patients with cystic fibrosis compared with healthy subjects (87.5%). This is a pioneer study showing that patients with cystic fibrosis exhibit significant reduction of H2-consuming microorganisms, which could increase hydrogen accumulation in the colon and the expulsion of this gas through non-microbial routes.},
}
@article {pmid27795311,
year = {2017},
author = {Rodrigues, MV and Borges, N and Santos, H},
title = {Glycerol Phosphate Cytidylyltransferase Stereospecificity Is Key to Understanding the Distinct Stereochemical Compositions of Glycerophosphoinositol in Bacteria and Archaea.},
journal = {Applied and environmental microbiology},
volume = {83},
number = {1},
pages = {},
pmid = {27795311},
issn = {1098-5336},
mesh = {Archaeoglobus/*enzymology/genetics/metabolism ; Bacteria/*enzymology/genetics/metabolism ; Cytidine Triphosphate/chemistry/*metabolism ; Glycerol/metabolism ; Inositol Phosphates/*chemistry/metabolism ; Magnetic Resonance Spectroscopy ; Molecular Conformation ; Nucleotidyltransferases/chemistry/*metabolism ; Recombinant Proteins/metabolism ; Stereoisomerism ; Substrate Specificity ; },
abstract = {Glycerophosphoinositol (GPI) is a compatible solute present in a few hyperthermophiles. Interestingly, different GPI stereoisomers accumulate in Bacteria and Archaea, and the basis for this domain-dependent specificity was investigated herein. The archaeon Archaeoglobus fulgidus and the bacterium Aquifex aeolicus were used as model organisms. The synthesis of GPI involves glycerol phosphate cytidylyltransferase (GCT), which catalyzes the production of CDP-glycerol from CTP and glycerol phosphate, and di-myo-inositol phosphate-phosphate synthase (DIPPS), catalyzing the formation of phosphorylated GPI from CDP-glycerol and l-myo-inositol 1-phosphate. DIPPS of A. fulgidus recognized the two CDP-glycerol stereoisomers similarly. This feature and the ability of 31P nuclear magnetic resonance (NMR) to distinguish the GPI diastereomers provided a means to study the stereospecificity of GCTs. The AF1418 gene and genes aq_185 and aq_1368 are annotated as putative GCT genes in the genomes of A. fulgidus and Aq. aeolicus, respectively. The functions of these genes were determined by assaying the activity of the respective recombinant proteins: AQ1368 and AQ185 are GCTs, while AF1418 has flavin adenine dinucleotide (FAD) synthetase activity. AQ185 is absolutely specific for sn-glycerol 3-phosphate, while AQ1368 recognizes the two enantiomers but has a 2:1 preference for sn-glycerol 3-phosphate. In contrast, the partially purified A. fulgidus GCT uses sn-glycerol 1-phosphate preferentially (4:1). Significantly, the predominant GPI stereoforms found in the bacterium and the archaeon reflect the distinct stereospecificities of the respective GCTs: i.e., A. fulgidus accumulates predominantly sn-glycero-1-phospho-3-l-myo-inositol, while Aq. aeolicus accumulates sn-glycero-3-phospho-3-l-myo-inositol.<br><br>IMPORTANCE: Compatible solutes of hyperthermophiles show high efficacy in thermal protection of proteins in comparison with solutes typical of mesophiles; therefore, they are potentially useful in several biotechnological applications. Glycerophosphoinositol (GPI) is synthesized from CDP-glycerol and l-myo-inositol 1-phosphate in a few hyperthermophiles. In this study, the molecular configuration of the GPI stereoisomers accumulated by members of the Bacteria and Archaea was established. The stereospecificity of glycerol phosphate cytidylyltransferase (GCT), the enzyme catalyzing the synthesis of CDP-glycerol, is crucial to the stereochemistry of GPI. However, the stereospecific properties of GCTs have not been investigated thus far. We devised a method to characterize GCT stereospecificity which does not require sn-glycerol 1-phosphate, a commercially unavailable substrate. This led us to understand the biochemical basis for the distinct GPI stereoisomer composition observed in archaea and bacteria.},
}
@article {pmid27749816,
year = {2016},
author = {Laso-Pérez, R and Wegener, G and Knittel, K and Widdel, F and Harding, KJ and Krukenberg, V and Meier, DV and Richter, M and Tegetmeyer, HE and Riedel, D and Richnow, HH and Adrian, L and Reemtsma, T and Lechtenfeld, OJ and Musat, F},
title = {Thermophilic archaea activate butane via alkyl-coenzyme M formation.},
journal = {Nature},
volume = {539},
number = {7629},
pages = {396-401},
pmid = {27749816},
issn = {1476-4687},
mesh = {Alkylation ; Anaerobiosis ; Archaea/genetics/*metabolism ; Archaeal Proteins/chemistry/genetics/metabolism ; Biocatalysis ; Butanes/*metabolism ; Evolution, Molecular ; Mesna/*chemistry/*metabolism ; Oxidation-Reduction ; Sulfates/metabolism ; Temperature ; },
abstract = {The anaerobic formation and oxidation of methane involve unique enzymatic mechanisms and cofactors, all of which are believed to be specific for C1-compounds. Here we show that an anaerobic thermophilic enrichment culture composed of dense consortia of archaea and bacteria apparently uses partly similar pathways to oxidize the C4 hydrocarbon butane. The archaea, proposed genus 'Candidatus Syntrophoarchaeum', show the characteristic autofluorescence of methanogens, and contain highly expressed genes encoding enzymes similar to methyl-coenzyme M reductase. We detect butyl-coenzyme M, indicating archaeal butane activation analogous to the first step in anaerobic methane oxidation. In addition, Ca. Syntrophoarchaeum expresses the genes encoding β-oxidation enzymes, carbon monoxide dehydrogenase and reversible C1 methanogenesis enzymes. This allows for the complete oxidation of butane. Reducing equivalents are seemingly channelled to HotSeep-1, a thermophilic sulfate-reducing partner bacterium known from the anaerobic oxidation of methane. Genes encoding 16S rRNA and methyl-coenzyme M reductase similar to those identifying Ca. Syntrophoarchaeum were repeatedly retrieved from marine subsurface sediments, suggesting that the presented activation mechanism is naturally widespread in the anaerobic oxidation of short-chain hydrocarbons.},
}
@article {pmid27791189,
year = {2016},
author = {Liu, Y and Vinyard, DJ and Reesbeck, ME and Suzuki, T and Manakongtreecheep, K and Holland, PL and Brudvig, GW and Söll, D},
title = {A [3Fe-4S] cluster is required for tRNA thiolation in archaea and eukaryotes.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {113},
number = {45},
pages = {12703-12708},
pmid = {27791189},
issn = {1091-6490},
support = {R01 GM022854/GM/NIGMS NIH HHS/United States ; R01 GM065313/GM/NIGMS NIH HHS/United States ; R37 GM022854/GM/NIGMS NIH HHS/United States ; UL1 TR001863/TR/NCATS NIH HHS/United States ; },
abstract = {The sulfur-containing nucleosides in transfer RNA (tRNAs) are present in all three domains of life; they have critical functions for accurate and efficient translation, such as tRNA structure stabilization and proper codon recognition. The tRNA modification enzymes ThiI (in bacteria and archaea) and Ncs6 (in archaea and eukaryotic cytosols) catalyze the formation of 4-thiouridine (s4U) and 2-thiouridine (s2U), respectively. The ThiI homologs were proposed to transfer sulfur via cysteine persulfide enzyme adducts, whereas the reaction mechanism of Ncs6 remains unknown. Here we show that ThiI from the archaeon Methanococcus maripaludis contains a [3Fe-4S] cluster that is essential for its tRNA thiolation activity. Furthermore, the archaeal and eukaryotic Ncs6 homologs as well as phosphoseryl-tRNA (Sep-tRNA):Cys-tRNA synthase (SepCysS), which catalyzes the Sep-tRNA to Cys-tRNA conversion in methanogens, also possess a [3Fe-4S] cluster similar to the methanogenic archaeal ThiI. These results suggest that the diverse tRNA thiolation processes in archaea and eukaryotic cytosols share a common mechanism dependent on a [3Fe-4S] cluster for sulfur transfer.},
}
@article {pmid27791118,
year = {2016},
author = {Ettwig, KF and Zhu, B and Speth, D and Keltjens, JT and Jetten, MSM and Kartal, B},
title = {Archaea catalyze iron-dependent anaerobic oxidation of methane.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {113},
number = {45},
pages = {12792-12796},
pmid = {27791118},
issn = {1091-6490},
support = {339880//European Research Council/International ; },
abstract = {Anaerobic oxidation of methane (AOM) is crucial for controlling the emission of this potent greenhouse gas to the atmosphere. Nitrite-, nitrate-, and sulfate-dependent methane oxidation is well-documented, but AOM coupled to the reduction of oxidized metals has so far been demonstrated only in environmental samples. Here, using a freshwater enrichment culture, we show that archaea of the order Methanosarcinales, related to &quot;Candidatus Methanoperedens nitroreducens,&quot; couple the reduction of environmentally relevant forms of Fe3+ and Mn4+ to the oxidation of methane. We obtained an enrichment culture of these archaea under anaerobic, nitrate-reducing conditions with a continuous supply of methane. Via batch incubations using [13C]methane, we demonstrated that soluble ferric iron (Fe3+, as Fe-citrate) and nanoparticulate forms of Fe3+ and Mn4+ supported methane-oxidizing activity. CO2 and ferrous iron (Fe2+) were produced in stoichiometric amounts. Our study connects the previous finding of iron-dependent AOM to microorganisms detected in numerous habitats worldwide. Consequently, it enables a better understanding of the interaction between the biogeochemical cycles of iron and methane.},
}
@article {pmid27137126,
year = {2016},
author = {Wrighton, KC and Castelle, CJ and Varaljay, VA and Satagopan, S and Brown, CT and Wilkins, MJ and Thomas, BC and Sharon, I and Williams, KH and Tabita, FR and Banfield, JF},
title = {RubisCO of a nucleoside pathway known from Archaea is found in diverse uncultivated phyla in bacteria.},
journal = {The ISME journal},
volume = {10},
number = {11},
pages = {2702-2714},
pmid = {27137126},
issn = {1751-7370},
support = {R01 GM095742/GM/NIGMS NIH HHS/United States ; },
mesh = {Archaea/genetics/growth &amp; development/isolation &amp; purification/*metabolism ; Archaeal Proteins/genetics/*metabolism ; Bacteria/genetics/growth &amp; development/isolation &amp; purification/*metabolism ; Bacterial Proteins/genetics/metabolism ; Fermentation ; Metagenomics ; Molecular Sequence Data ; Nucleosides/*metabolism ; Phylogeny ; Ribulose-Bisphosphate Carboxylase/genetics ; },
abstract = {Metagenomic studies recently uncovered form II/III RubisCO genes, originally thought to only occur in archaea, from uncultivated bacteria of the candidate phyla radiation (CPR). There are no isolated CPR bacteria and these organisms are predicted to have limited metabolic capacities. Here we expand the known diversity of RubisCO from CPR lineages. We report a form of RubisCO, distantly similar to the archaeal form III RubisCO, in some CPR bacteria from the Parcubacteria (OD1), WS6 and Microgenomates (OP11) phyla. In addition, we significantly expand the Peregrinibacteria (PER) II/III RubisCO diversity and report the first II/III RubisCO sequences from the Microgenomates and WS6 phyla. To provide a metabolic context for these RubisCOs, we reconstructed near-complete (>93%) PER genomes and the first closed genome for a WS6 bacterium, for which we propose the phylum name Dojkabacteria. Genomic and bioinformatic analyses suggest that the CPR RubisCOs function in a nucleoside pathway similar to that proposed in Archaea. Detection of form II/III RubisCO and nucleoside metabolism gene transcripts from a PER supports the operation of this pathway in situ. We demonstrate that the PER form II/III RubisCO is catalytically active, fixing CO2 to physiologically complement phototrophic growth in a bacterial photoautotrophic RubisCO deletion strain. We propose that the identification of these RubisCOs across a radiation of obligately fermentative, small-celled organisms hints at a widespread, simple metabolic platform in which ribose may be a prominent currency.},
}
@article {pmid27771364,
year = {2016},
author = {Loder, AJ and Han, Y and Hawkins, AB and Lian, H and Lipscomb, GL and Schut, GJ and Keller, MW and Adams, MWW and Kelly, RM},
title = {Reaction kinetic analysis of the 3-hydroxypropionate/4-hydroxybutyrate CO2 fixation cycle in extremely thermoacidophilic archaea.},
journal = {Metabolic engineering},
volume = {38},
number = {},
pages = {446-463},
pmid = {27771364},
issn = {1096-7184},
support = {T32 GM008776/GM/NIGMS NIH HHS/United States ; },
mesh = {Archaea/metabolism ; Carbon Dioxide/*metabolism ; Extremophiles/metabolism ; Hydroxybutyrates/*metabolism ; Kinetics ; Lactic Acid/*analogs &amp; derivatives/metabolism ; Metabolic Clearance Rate ; Metabolic Flux Analysis/*methods ; Metabolic Networks and Pathways/*physiology ; *Models, Biological ; Signal Transduction/physiology ; Sulfolobaceae/*metabolism ; },
abstract = {The 3-hydroxypropionate/4-hydroxybutyrate (3HP/4HB) cycle fixes CO2 in extremely thermoacidophilic archaea and holds promise for metabolic engineering because of its thermostability and potentially rapid pathway kinetics. A reaction kinetics model was developed to examine the biological and biotechnological attributes of the 3HP/4HB cycle as it operates in Metallosphaera sedula, based on previous information as well as on kinetic parameters determined here for recombinant versions of five of the cycle enzymes (malonyl-CoA/succinyl-CoA reductase, 3-hydroxypropionyl-CoA synthetase, 3-hydroxypropionyl-CoA dehydratase, acryloyl-CoA reductase, and succinic semialdehyde reductase). The model correctly predicted previously observed features of the cycle: the 35-65% split of carbon flux through the acetyl-CoA and succinate branches, the high abundance and relative ratio of acetyl-CoA/propionyl-CoA carboxylase (ACC) and MCR, and the significance of ACC and hydroxybutyryl-CoA synthetase (HBCS) as regulated control points for the cycle. The model was then used to assess metabolic engineering strategies for incorporating CO2 into chemical intermediates and products of biotechnological importance: acetyl-CoA, succinate, and 3-hydroxypropionate.},
}
@article {pmid27771305,
year = {2016},
author = {Walter, ME and Ortiz, A and Sondgeroth, C and Sindt, NM and Duszenko, N and Catlett, JL and Zhou, Y and Valloppilly, S and Anderson, C and Fernando, S and Buan, NR},
title = {High-throughput mutation, selection, and phenotype screening of mutant methanogenic archaea.},
journal = {Journal of microbiological methods},
volume = {131},
number = {},
pages = {113-121},
doi = {10.1016/j.mimet.2016.10.010},
pmid = {27771305},
issn = {1872-8359},
mesh = {Acetates/metabolism ; Archaea/*genetics/*isolation &amp; purification/metabolism/*radiation effects ; DNA, Archaeal/genetics/radiation effects ; Genes, Archaeal ; High-Throughput Screening Assays/*methods ; Methane/metabolism ; Methanol/metabolism ; Methanosarcina/genetics/growth &amp; development/radiation effects ; Methyltransferases/genetics ; Microbial Viability/radiation effects ; Mutagenesis/radiation effects ; *Phenotype ; Point Mutation/*radiation effects ; *Ultraviolet Rays ; },
abstract = {Bacterial and archaeal genomes can contain 30% or more hypothetical genes with no predicted function. Phylogenetically deep-branching microbes, such as methane-producing archaea (methanogens), contain up to 50% genes with unknown function. In order to formulate hypotheses about the function of hypothetical gene functions in the strict anaerobe, Methanosarcina acetivorans, we have developed high-throughput anaerobic techniques to UV mutagenize, screen, and select for mutant strains in 96-well plates. Using these approaches we have isolated 10 mutant strains that exhibit a variety of physiological changes including increased or decreased growth rate relative to the parent strain when cells use methanol and/or acetate as carbon and energy sources. This method provides an avenue for the first step in identifying new gene functions: associating a genetic mutation with a reproducible phenotype. Mutations in bona fide methanogenesis genes such as corrinoid methyltransferases and proton-translocating F420H2:methanophenazine oxidoreductase (Fpo) were also generated, opening the door to in vivo functional complementation experiments. Irradiation-based mutagenesis such as from ultraviolet (UV) light, combined with modern genome sequencing, is a useful procedure to discern systems-level gene function in prokaryote taxa that can be axenically cultured but which may be resistant to chemical mutagens.},
}
@article {pmid27752237,
year = {2016},
author = {Sarcinelli, C and Fiorentino, G and Pizzo, E and Bartolucci, S and Limauro, D},
title = {Discovering Antioxidant Molecules in the Archaea Domain: Peroxiredoxin Bcp1 from Sulfolobus solfataricus Protects H9c2 Cardiomyoblasts from Oxidative Stress.},
journal = {Archaea (Vancouver, B.C.)},
volume = {2016},
number = {},
pages = {7424870},
pmid = {27752237},
issn = {1472-3654},
mesh = {Animals ; Antioxidants/*isolation &amp; purification/*metabolism ; Apoptosis ; Cell Line ; Hydrogen Peroxide/metabolism/toxicity ; Hydrogen-Ion Concentration ; Myocytes, Cardiac/*drug effects/physiology ; Oxidation-Reduction ; *Oxidative Stress ; Peroxiredoxins/genetics/*isolation &amp; purification/*metabolism ; Rats ; Sulfolobus solfataricus/*enzymology/genetics ; Temperature ; },
abstract = {Peroxiredoxins (Prxs) are ubiquitous thiol peroxidases that are involved in the reduction of peroxides. It has been reported that prokaryotic Prxs generally show greater structural robustness than their eukaryotic counterparts, making them less prone to inactivation by overoxidation. This difference has inspired the search for new antioxidants from prokaryotic sources that can be used as possible therapeutic biodrugs. Bacterioferritin comigratory proteins (Bcps) of the hyperthermophilic archaeon Sulfolobus solfataricus that belong to the Prx family have recently been characterized. One of these proteins, Bcp1, was chosen to determine its antioxidant effects in H9c2 rat cardiomyoblast cells. Bcp1 activity was measured in vitro under physiological temperature and pH conditions that are typical of mammalian cells; the yeast thioredoxin reductase (yTrxR)/thioredoxin (yTrx) reducing system was used to evaluate enzyme activity. A TAT-Bcp1 fusion protein was constructed to allow its internalization and verify the effect of Bcp1 on H9c2 rat cardiomyoblasts subjected to oxidative stress. The results reveal that TAT-Bcp1 is not cytotoxic and inhibits H2O2-induced apoptosis in H9c2 cells by reducing the H2O2 content inside these cells.},
}
@article {pmid27729650,
year = {2016},
author = {Du Toit, A},
title = {Archaeal genomics: Divergent methanogenic archaea.},
journal = {Nature reviews. Microbiology},
volume = {14},
number = {11},
pages = {667},
pmid = {27729650},
issn = {1740-1534},
}
@article {pmid27725793,
year = {2016},
author = {Esquivel-Elizondo, S and Parameswaran, P and Delgado, AG and Maldonado, J and Rittmann, BE and Krajmalnik-Brown, R},
title = {Archaea and Bacteria Acclimate to High Total Ammonia in a Methanogenic Reactor Treating Swine Waste.},
journal = {Archaea (Vancouver, B.C.)},
volume = {2016},
number = {},
pages = {4089684},
pmid = {27725793},
issn = {1472-3654},
mesh = {Ammonia/*metabolism ; Anaerobiosis ; Animals ; Archaea/*classification/genetics/growth &amp; development/*metabolism ; Bacteria/*classification/genetics/growth &amp; development/*metabolism ; Biological Oxygen Demand Analysis ; Bioreactors/*microbiology ; *Biota ; Culture Media/chemistry ; Manure ; Real-Time Polymerase Chain Reaction ; Swine ; },
abstract = {Inhibition by ammonium at concentrations above 1000 mgN/L is known to harm the methanogenesis phase of anaerobic digestion. We anaerobically digested swine waste and achieved steady state COD-removal efficiency of around 52% with no fatty-acid or H2 accumulation. As the anaerobic microbial community adapted to the gradual increase of total ammonia-N (NH3-N) from 890 ± 295 to 2040 ± 30 mg/L, the Bacterial and Archaeal communities became less diverse. Phylotypes most closely related to hydrogenotrophic Methanoculleus (36.4%) and Methanobrevibacter (11.6%), along with acetoclastic Methanosaeta (29.3%), became the most abundant Archaeal sequences during acclimation. This was accompanied by a sharp increase in the relative abundances of phylotypes most closely related to acetogens and fatty-acid producers (Clostridium, Coprococcus, and Sphaerochaeta) and syntrophic fatty-acid Bacteria (Syntrophomonas, Clostridium, Clostridiaceae species, and Cloacamonaceae species) that have metabolic capabilities for butyrate and propionate fermentation, as well as for reverse acetogenesis. Our results provide evidence countering a prevailing theory that acetoclastic methanogens are selectively inhibited when the total ammonia-N concentration is greater than ~1000 mgN/L. Instead, acetoclastic and hydrogenotrophic methanogens coexisted in the presence of total ammonia-N of ~2000 mgN/L by establishing syntrophic relationships with fatty-acid fermenters, as well as homoacetogens able to carry out forward and reverse acetogenesis.},
}
@article {pmid27720988,
year = {2016},
author = {Ciragan, A and Aranko, AS and Tascon, I and Iwaï, H},
title = {Salt-inducible Protein Splicing in cis and trans by Inteins from Extremely Halophilic Archaea as a Novel Protein-Engineering Tool.},
journal = {Journal of molecular biology},
volume = {428},
number = {23},
pages = {4573-4588},
doi = {10.1016/j.jmb.2016.10.006},
pmid = {27720988},
issn = {1089-8638},
mesh = {Bacterial Proteins/metabolism ; Enzyme Activators/*metabolism ; Halobacteriales/*enzymology/metabolism ; *Inteins ; Isotope Labeling/methods ; Membrane Proteins/metabolism ; Protein Engineering/*methods ; *Protein Splicing ; Salts/*metabolism ; },
abstract = {Intervening protein sequences (inteins) from extremely halophilic haloarchaea can be inactive under low salinity but could be activated by increasing the salt content to a specific concentration for each intein. The halo-obligatory inteins confer high solubility under both low and high salinity conditions. We showed the broad utility of salt-dependent protein splicing in cis and trans by demonstrating backbone cyclization, self-cleavage for purification, and scarless protein ligation for segmental isotopic labeling. Artificially split MCM2 intein derived from Halorhabdus utahensis remained highly soluble and was capable of protein trans-splicing with excellent ligation kinetics by reassembly under high salinity conditions. Importantly, the MCM2 intein has the active site residue of Ser at the +1 position, which remains in the ligated product, instead of Cys as found in many other efficient split inteins. Since Ser is more abundant than Cys in proteins, the novel split intein could widen the applications of segmental labeling in protein NMR spectroscopy and traceless protein ligation by exploiting a Ser residue in the native sequences as the +1 position of the MCM2 intein. The split halo-obligatory intein was successfully used to demonstrate the utility in NMR investigation of intact proteins by producing segmentally isotope-labeled intact TonB protein from Helicobacter pylori.},
}
@article {pmid27687996,
year = {2016},
author = {Cerrillo, M and Morey, L and Viñas, M and Bonmatí, A},
title = {Assessment of active methanogenic archaea in a methanol-fed upflow anaerobic sludge blanket reactor.},
journal = {Applied microbiology and biotechnology},
volume = {100},
number = {23},
pages = {10137-10146},
doi = {10.1007/s00253-016-7862-4},
pmid = {27687996},
issn = {1432-0614},
mesh = {Acetates/metabolism ; Anaerobiosis ; Archaea/*classification/genetics/*metabolism ; Bioreactors/*microbiology ; DNA, Ribosomal/chemistry/genetics ; High-Throughput Nucleotide Sequencing ; Hydrogen/metabolism ; Methane/*metabolism ; Methanol/*metabolism ; Oxidoreductases/genetics ; RNA, Ribosomal, 16S/genetics ; Real-Time Polymerase Chain Reaction ; Sequence Analysis, DNA ; Sewage/*microbiology ; },
abstract = {Methanogenic archaea enrichment of a granular sludge was undertaken in an upflow anaerobic sludge blanket (UASB) reactor fed with methanol in order to enrich methylotrophic and hydrogenotrophic methanogenic populations. A microbial community assessment, in terms of microbial composition and activity-throughout the different stages of the feeding process with methanol and acetate-was performed using specific methanogenic activity (SMA) assays, quantitative real-time polymerase chain reaction (qPCR), and high-throughput sequencing of 16S ribosomal RNA (rRNA) genes from DNA and complementary DNA (cDNA). Distinct methanogenic enrichment was revealed by qPCR of mcrA gene in the methanol-fed community, being two orders of magnitude higher with respect to the initial inoculum, achieving a final mcrA/16S rRNA ratio of 0.25. High-throughput sequencing analysis revealed that the resulting methanogenic population was mainly composed by methylotrophic archaea (Methanomethylovorans and Methanolobus genus), being also highly active according to the RNA-based assessment. SMA confirmed that the methylotrophic pathway, with a direct conversion of methanol to CH4, was the main step of methanol degradation in the UASB. The biomass from the UASB, enriched in methanogenic archaea, may bear great potential as additional inoculum for bioreactors to carry out biogas production and other related processes.},
}
@article {pmid27683365,
year = {2016},
author = {Gulbudak, H and Weitz, JS},
title = {A touch of sleep: biophysical model of contact-mediated dormancy of archaea by viruses.},
journal = {Proceedings. Biological sciences},
volume = {283},
number = {1839},
pages = {},
pmid = {27683365},
issn = {1471-2954},
abstract = {The canonical view of the interactions between viruses and their microbial hosts presumes that changes in host and virus fate requires the initiation of infection of a host by a virus. Infection may lead to the death of the host cell and release of viruses, to the elimination of the viral genome through cellular defence mechanisms or the integration of the viral genome with the host as a chromosomal or extrachromosomal element. Here, we revisit this canonical view, inspired by recent experimental findings in which the majority of target host cells can be induced into a dormant state when exposed to either active or deactivated viruses, even when viruses are present at low relative titre. We propose that both the qualitative phenomena and the quantitative timescales of dormancy induction are consistent with the hypothesis that cellular physiology can be altered by contact on the surface of host cells rather than strictly by infection In order to test this hypothesis, we develop and study a biophysical model of contact-mediated dynamics involving virus particles and target cells. We show how virus particles can catalyse cellular transformations among many cells, even if they ultimately infect only one (or none). We also find that population-scale dormancy is robust to variation in the representation of model dynamics, including cell growth, death and recovery.},
}
@article {pmid27681926,
year = {2016},
author = {Lauer, A and Sørensen, KB and Teske, A},
title = {Phylogenetic Characterization of Marine Benthic Archaea in Organic-Poor Sediments of the Eastern Equatorial Pacific Ocean (ODP Site 1225).},
journal = {Microorganisms},
volume = {4},
number = {3},
pages = {},
pmid = {27681926},
issn = {2076-2607},
abstract = {Sequencing surveys of microbial communities in marine subsurface sediments have focused on organic-rich, continental margins; the database for organic-lean deep-sea sediments from mid-ocean regions is underdeveloped. The archaeal community in subsurface sediments of ODP Site 1225 in the eastern equatorial Pacific (3760 m water depth; 1.1 and 7.8 m sediment depth) was analyzed by PCR, cloning and sequencing, and by denaturant gradient gel electrophoresis (DGGE) of 16S rRNA genes. Three uncultured archaeal lineages with different depth distributions were found: Marine Group I (MG-I) within the Thaumarchaeota, its sister lineage Marine Benthic Group A (MBG-A), the phylum-level archaeal lineage Marine Benthic Group B (also known as Deep-Sea Archaeal Group or Lokiarchaeota), and the Deep-Sea Euryarchaeotal Group 3. The MG-I phylotypes included representatives of sediment clusters that are distinct from the pelagic members of this phylum. On the scale from fully oxidized, extremely organic carbon-depleted sediments (for example, those the South Pacific Gyre) to fully reduced, organic carbon-rich marine subsurface sediments (such as those of the Peru Margin), Ocean Drilling Program (ODP) Site 1225 falls into the non-extreme organic carbon-lean category, and harbors archaeal communities from both ends of the spectrum.},
}
@article {pmid27679621,
year = {2016},
author = {Zu, Q and Zhong, L and Deng, Y and Shi, Y and Wang, B and Jia, Z and Lin, X and Feng, Y},
title = {Geographical Distribution of Methanogenic Archaea in Nine Representative Paddy Soils in China.},
journal = {Frontiers in microbiology},
volume = {7},
number = {},
pages = {1447},
pmid = {27679621},
issn = {1664-302X},
abstract = {Paddy field methanogenic archaea are responsible for methane (CH4) production and contribute significantly to climate change. The information regarding the spatial variations in the abundance, the diversity and the composition of such ecologically important microbes, however, is quite limited at large scale. In this investigation, we studied the abundance, alpha diversity and geographical distribution of methanogenic archaeal communities in nine representative paddy sites, along a large latitudinal gradient in China, using pyrosequencing and real-time quantitative PCR. It is found that all paddy soils harbor constant methanogenic archaeal constituents, which is dominated by family Methanocellaceae (37.3%), Methanobacteriaceae (22.1%), Methanosaetaceae (17.2%), and Methanosarcinaceae (9.8%). Methanogenic archaeal abundance is primarily influenced by soil C (R = 0.612, P = 0.001) and N (R = 0.673, P = 0.001) contents, as well as alpha diversity by soil pH (PD: R = -0.552, P = 0.006; Chao1: R = -0.615, P = 0.002). Further exploration revealed that both spatial distance (R = 0.3469, P = 0.001, partial mental test) and soil chemical variables mainly about soil C and N (R = 0.2847, P = 0.001) are the two major factors affecting methanogenic archaeal community composition distribution in paddy soils. This finding will allow us to develop a better picture of the biogeographic ranges of these ecologically important microbes and get deeper insights into their ecology.},
}
@article {pmid27679616,
year = {2016},
author = {Chistoserdova, L},
title = {Wide Distribution of Genes for Tetrahydromethanopterin/Methanofuran-Linked C1 Transfer Reactions Argues for Their Presence in the Common Ancestor of Bacteria and Archaea.},
journal = {Frontiers in microbiology},
volume = {7},
number = {},
pages = {1425},
pmid = {27679616},
issn = {1664-302X},
}
@article {pmid27679615,
year = {2016},
author = {Thombre, RS and Shinde, V and Thaiparambil, E and Zende, S and Mehta, S},
title = {Antimicrobial Activity and Mechanism of Inhibition of Silver Nanoparticles against Extreme Halophilic Archaea.},
journal = {Frontiers in microbiology},
volume = {7},
number = {},
pages = {1424},
pmid = {27679615},
issn = {1664-302X},
abstract = {Haloarchaea are salt-loving halophilic microorganisms that inhabit marine environments, sea water, salterns, and lakes. The resistance of haloarchaea to physical extremities that challenge organismic survival is ubiquitous. Metal and antibiotic resistance of haloarchaea has been on an upsurge due to the exposure of these organisms to metal sinks and drug resistance genes augmented in their natural habitats due to anthropogenic activities and environmental pollution. The efficacy of silver nanoparticles (SNPs) as a potent and broad spectrum inhibitory agent is known, however, there are no reports on the inhibitory activity of SNPs against haloarchaea. In the present study, we have investigated the antimicrobial potentials of SNPs synthesized using aqueous leaf extract of Cinnamomum tamala against antibiotic resistant haloarchaeal isolates Haloferax prahovense RR8, Haloferax lucentense RR15, Haloarcula argentinensis RR10 and Haloarcula tradensis RR13. The synthesized SNPs were characterized by UV-Vis spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, dynamic light scattering, X-ray diffraction and Fourier transform infrared spectroscopy. The SNPs demonstrated potent antimicrobial activity against the haloarchaea with a minimum inhibitory concentration of 300-400 μg/ml. Growth kinetics of haloarchaea in the presence of SNPs was studied by employing the Baranyi mathematical model for microbial growth using the DMFit curve fitting program. The C. tamala SNPs also demonstrated cytotoxic activity against human lung adenocarcinoma epithelial cell line (A540) and human breast adenocarcinoma cell line (MCF-7). The mechanism of inhibition of haloarchaea by the SNPs was investigated. The plausible mechanism proposed is the alterations and disruption of haloarchaeal membrane permeability by turbulence, inhibition of respiratory dehydrogenases and lipid peroxidation causing cellular and DNA damage resulting in cell death.},
}
@article {pmid27670118,
year = {2016},
author = {Dar, D and Prasse, D and Schmitz, RA and Sorek, R},
title = {Widespread formation of alternative 3' UTR isoforms via transcription termination in archaea.},
journal = {Nature microbiology},
volume = {1},
number = {10},
pages = {16143},
pmid = {27670118},
issn = {2058-5276},
mesh = {*3' Untranslated Regions ; Archaea/*genetics ; Archaeal Proteins/genetics ; Gene Expression Profiling ; *Gene Expression Regulation, Archaeal ; Genes, Archaeal ; RNA Isoforms/*genetics ; RNA, Archaeal/*genetics ; RNA, Untranslated ; *Transcription Termination, Genetic ; },
abstract = {Transcription termination sets the 3' end boundaries of RNAs and plays key roles in gene regulation. Although termination has been well studied in bacteria, the signals that mediate termination in archaea remain poorly understood. Here, we applied term-seq to comprehensively map RNA 3' termini, with single-base precision, in two phylogenetically distant archaea: Methanosarcina mazei and Sulfolobus acidocaldarius. Comparison of RNA 3' ends across hundreds of genes revealed the sequence composition of transcriptional terminators in each organism, highlighting both common and divergent characteristics between the different archaeal phyla. We find that, in contrast to bacteria, a considerable portion of archaeal genes are controlled by multiple consecutive terminators, generating several alternative 3' untranslated region isoforms for >30% of the genes. These alternative isoforms often present marked length differences, implying that archaea can employ regulation via alternative 3' untranslated regions, similar to eukaryotes. Although most of the terminators are intergenic, we discover numerous cases in which termination of one gene occurs within the coding region of a downstream gene, implying that leaky termination may tune inter-transcript stoichiometry in multi-gene operons. These results provide the first high-throughput maps of transcriptional terminators in archaea and point to an evolutionary path linking bacterial and eukaryal non-coding regulatory strategies.},
}
@article {pmid27652169,
year = {2016},
author = {Watanabe, K and Kohzu, A and Suda, W and Yamamura, S and Takamatsu, T and Takenaka, A and Koshikawa, MK and Hayashi, S and Watanabe, M},
title = {Microbial nitrification in throughfall of a Japanese cedar associated with archaea from the tree canopy.},
journal = {SpringerPlus},
volume = {5},
number = {1},
pages = {1596},
pmid = {27652169},
issn = {2193-1801},
abstract = {To investigate the nitrification potential of phyllospheric microbes, we incubated throughfall samples collected under the canopies of Japanese cedar (Cryptomeria japonica) and analyzed the transformation of inorganic nitrogen in the samples. Nitrate concentration increased in the unfiltered throughfall after 4 weeks of incubation, but remained nearly constant in the filtered samples (pore size: 0.2 and 0.4 µm). In the unfiltered samples, δ(18)O and δ(15)N values of nitrate decreased during incubation. In addition, archaeal ammonia monooxygenase subunit A (amoA) genes, which participate in the oxidation of ammonia, were found in the throughfall samples, although betaproteobacterial amoA genes were not detected. The amoA genes recovered from the leaf surface of C. japonica were also from archaea. Conversely, nitrate production, decreased isotope ratios of nitrate, and the presence of amoA genes was not observed in rainfall samples collected from an open area. Thus, the microbial nitrification that occurred in the incubated throughfall is likely due to ammonia-oxidizing archaea that were washed off the tree canopy by precipitation.},
}
@article {pmid27642845,
year = {2016},
author = {Umu, SU and Poole, AM and Dobson, RC and Gardner, PP},
title = {Avoidance of stochastic RNA interactions can be harnessed to control protein expression levels in bacteria and archaea.},
journal = {eLife},
volume = {5},
number = {},
pages = {},
pmid = {27642845},
issn = {2050-084X},
mesh = {Archaea/*genetics/*metabolism ; Bacteria/*genetics/*metabolism ; Genes, Reporter ; Green Fluorescent Proteins/analysis/genetics ; *Protein Biosynthesis ; RNA, Messenger/*metabolism ; RNA, Untranslated/*metabolism ; },
abstract = {A critical assumption of gene expression analysis is that mRNA abundances broadly correlate with protein abundance, but these two are often imperfectly correlated. Some of the discrepancy can be accounted for by two important mRNA features: codon usage and mRNA secondary structure. We present a new global factor, called mRNA:ncRNA avoidance, and provide evidence that avoidance increases translational efficiency. We also demonstrate a strong selection for the avoidance of stochastic mRNA:ncRNA interactions across prokaryotes, and that these have a greater impact on protein abundance than mRNA structure or codon usage. By generating synonymously variant green fluorescent protein (GFP) mRNAs with different potential for mRNA:ncRNA interactions, we demonstrate that GFP levels correlate well with interaction avoidance. Therefore, taking stochastic mRNA:ncRNA interactions into account enables precise modulation of protein abundance.},
}
@article {pmid27624130,
year = {2016},
author = {Quemin, ER and Chlanda, P and Sachse, M and Forterre, P and Prangishvili, D and Krupovic, M},
title = {Eukaryotic-Like Virus Budding in Archaea.},
journal = {mBio},
volume = {7},
number = {5},
pages = {},
pmid = {27624130},
issn = {2150-7511},
mesh = {Archaea/ultrastructure/*virology ; Electron Microscope Tomography ; Fuselloviridae/*physiology/ultrastructure ; *Virus Release ; },
abstract = {UNLABELLED: Similar to many eukaryotic viruses (and unlike bacteriophages), viruses infecting archaea are often encased in lipid-containing envelopes. However, the mechanisms of their morphogenesis and egress remain unexplored. Here, we used dual-axis electron tomography (ET) to characterize the morphogenesis of Sulfolobus spindle-shaped virus 1 (SSV1), the prototype of the family Fuselloviridae and representative of the most abundant archaea-specific group of viruses. Our results show that SSV1 assembly and egress are concomitant and occur at the cellular cytoplasmic membrane via a process highly reminiscent of the budding of enveloped viruses that infect eukaryotes. The viral nucleoprotein complexes are extruded in the form of previously unknown rod-shaped intermediate structures which have an envelope continuous with the host membrane. Further maturation into characteristic spindle-shaped virions takes place while virions remain attached to the cell surface. Our data also revealed the formation of constricted ring-like structures which resemble the budding necks observed prior to the ESCRT machinery-mediated membrane scission during egress of various enveloped viruses of eukaryotes. Collectively, we provide evidence that archaeal spindle-shaped viruses contain a lipid envelope acquired upon budding of the viral nucleoprotein complex through the host cytoplasmic membrane. The proposed model bears a clear resemblance to the egress strategy employed by enveloped eukaryotic viruses and raises important questions as to how the archaeal single-layered membrane composed of tetraether lipids can undergo scission.<br><br>IMPORTANCE: The replication of enveloped viruses has been extensively studied in eukaryotes but has remained unexplored for enveloped viruses infecting Archaea Here, we provide a sequential view on the assembly and egress of SSV1, a prototypic archaeal virus. The observed process is highly similar to the budding of eukaryotic enveloped viruses, including human immunodeficiency virus, influenza virus, and Ebola virus. The present study is the first to characterize such a phenomenon in archeal cells, showing that membrane budding is not an exclusive feature of eukaryotic viruses. Our results provide significant insights into the biogenesis and architecture of unique, spindle-shaped virions that infect archaea. Furthermore, our findings open doors for future inquiries into (i) the evolution of the virus budding process, (ii) mechanistic details of virus-mediated membrane scission in Archaea, and (iii) elucidation of virus- and host-encoded molecular players responsible for archaeal membrane and surface remodeling.},
}
@article {pmid27598206,
year = {2016},
author = {Jones, DL and Baxter, BK},
title = {Bipyrimidine Signatures as a Photoprotective Genome Strategy in G + C-rich Halophilic Archaea.},
journal = {Life (Basel, Switzerland)},
volume = {6},
number = {3},
pages = {},
pmid = {27598206},
issn = {2075-1729},
abstract = {Halophilic archaea experience high levels of ultraviolet (UV) light in their environments and demonstrate resistance to UV irradiation. DNA repair systems and carotenoids provide UV protection but do not account for the high resistance observed. Herein, we consider genomic signatures as an additional photoprotective strategy. The predominant forms of UV-induced DNA damage are cyclobutane pyrimidine dimers, most notoriously thymine dimers (T^Ts), which form at adjacent Ts. We tested whether the high G + C content seen in halophilic archaea serves a photoprotective function through limiting T nucleotides, and thus T^T lesions. However, this speculation overlooks the other bipyrimidine sequences, all of which capable of forming photolesions to varying degrees. Therefore, we designed a program to determine the frequencies of the four bipyrimidine pairs (5' to 3': TT, TC, CT, and CC) within genomes of halophilic archaea and four other randomized sample groups for comparison. The outputs for each sampled genome were weighted by the intrinsic photoreactivities of each dinucleotide pair. Statistical methods were employed to investigate intergroup differences. Our findings indicate that the UV-resistance seen in halophilic archaea can be attributed in part to a genomic strategy: high G + C content and the resulting bipyrimidine signature reduces the genomic photoreactivity.},
}
@article {pmid27596731,
year = {2016},
author = {Zhang, X and Tang, Y and Shi, Y and He, N and Wen, X and Yu, Q and Zheng, C and Sun, X and Qiu, W},
title = {Responses of soil hydrolytic enzymes, ammonia-oxidizing bacteria and archaea to nitrogen applications in a temperate grassland in Inner Mongolia.},
journal = {Scientific reports},
volume = {6},
number = {},
pages = {32791},
pmid = {27596731},
issn = {2045-2322},
mesh = {Ammonia/*metabolism ; Archaea/*metabolism ; Bacteria/*metabolism ; China ; Ecosystem ; Fertilizers/microbiology ; Grassland ; Hydrolysis ; Nitrification/physiology ; Nitrogen/*metabolism ; Oxidation-Reduction ; Soil ; Soil Microbiology ; },
abstract = {We used a seven-year urea gradient applied field experiment to investigate the effects of nitrogen (N) applications on soil N hydrolytic enzyme activity and ammonia-oxidizing microbial abundance in a typical steppe ecosystem in Inner Mongolia. The results showed that N additions inhibited the soil N-related hydrolytic enzyme activities, especially in 392 kg N ha(-1)yr(-1) treatment. As N additions increased, the amoA gene copy ratios of ammonia-oxidizing archaea (AOA) to ammonia-oxidizing bacteria (AOB) decreased from 1.13 to 0.65. Pearson correlation analysis showed that the AOA gene copies were negatively related with NH4(+)-N content. However, the AOB gene copies were positively correlated with NO3(-)-N content. Moderate N application rates (56-224 kg N ha(-1)yr(-1)) accompanied by P additions are beneficial to maintaining the abundance of AOB, as opposed to the inhibition of highest N application rate (392 kg N ha(-1)yr(-1)) on the abundance of AOB. This study suggests that the abundance of AOB and AOA would not decrease unless N applications exceed 224 kg N ha(-1)yr(-1) in temperate grasslands in Inner Mongolia.},
}
@article {pmid27582505,
year = {2016},
author = {Pergolizzi, G and Wagner, GK and Bowater, RP},
title = {Biochemical and Structural Characterisation of DNA Ligases from Bacteria and Archaea.},
journal = {Bioscience reports},
volume = {36},
number = {5},
pages = {00391},
pmid = {27582505},
issn = {1573-4935},
abstract = {DNA ligases are enzymes that seal breaks in the backbones of DNA, leading to them being essential for the survival of all organisms. DNA ligases have been studied from many different types of cells and organisms and shown to have diverse sizes and sequences, with well conserved specific sequences that are required for enzymatic activity. A significant number of DNA ligases have been isolated or prepared in recombinant forms and, here, we review their biochemical and structural characterisation. All DNA ligases contain an essential lysine that transfers an adenylate group from a co-factor to the 5'-phosphate of the DNA end that will ultimately be joined to the 3'-hydroxyl of the neighbouring DNA strand. The essential DNA ligases in bacteria use nicotinamide adenine dinucleotide (β -NAD+) as their co-factor whereas those that are essential in other cells use adenosine-5'-triphosphate (ATP) as their co-factor. This observation suggests that the essential bacterial enzyme could be targeted by novel antibiotics and the complex molecular structure of β -NAD+ affords multiple opportunities for chemical modification. Several recent studies have synthesised novel derivatives and their biological activity against a range of DNA ligases has been evaluated as inhibitors for drug discovery and/or non-natural substrates for biochemical applications. Here, we review the recent advances that herald new opportunities to alter the biochemical activities of these important enzymes. The recent development of modified derivatives of nucleotides highlights that the continued combination of structural, biochemical and biophysical techniques will be useful in targeting these essential cellular enzymes.},
}
@article {pmid29251473,
year = {2016},
author = {Dong, L and Meng, Y and Wang, J and Sun, G},
title = {Effects of Transgenic Bt+CpTI cotton on the abundance and diversity of rhizosphere ammonia oxidizing bacteria and archaea.},
journal = {Journal of environmental biology},
volume = {37},
number = {5},
pages = {881-888},
pmid = {29251473},
issn = {0254-8704},
mesh = {Ammonia/*metabolism ; Archaea/classification/*metabolism ; Bacteria/classification/*metabolism ; DNA, Archaeal/genetics ; DNA, Bacterial/genetics ; Gossypium/*genetics ; Oxidation-Reduction ; Plant Roots ; Plants, Genetically Modified ; Soil ; *Soil Microbiology ; },
abstract = {Genetically modified crops (GMCs) hold great promise for improving agricultural output, but at the same time present challenges in terms of environmental safety assessment. Ammonia oxidizers, including ammonia oxidizing bacteria (AOB) and archaea (AOA), are very important functional microbial groups in nitrogen cycle. The abundance and diversity of AOA and AOB in the rhizosphere of genetically modified cotton (SGK321) and non-GM cotton (SY321) across growth stages were investigated using real time quantitative PCR (qPCR) and terminal restriction fragment length polymorphism (T-RFLP). Results showed that cotton genotype had a significant effect on the change in abundance of AOA and AOB, as indicated by amoA copy number. Variations in AOB abundance in rhizosphere of SY321 differed from those in SGK321. The number of AOB in the rhizosphere of SY321 fluctuated considerably: It dramatically decreased from 1.2?106 copies g-1 dry soil to 3?105 copies g-1 dry soil during the flowering stage and then increased to 1.1?106 copies g-1 and 1.5?106 copies g-1 at the belling and boll opening stages, respectively. However, abundance of AOB in the rhizosphere of SGK321 was relatively stable during all the stages of growth. The effect of SGK321 and SY321 on AOA number was quite similar to that of AOB: AOA abundance in SGK321 increased smoothly from 1.0 ?105 copies g-1 dry soil to 1.4?106 copies g-1 dry soil during growth, but that in SY321 fluctuated. Correspondence analysis (CA), canonical CA (CCA), and partial CCA (pCCA) of T-RFLP profiles of AOA and AOB showed that AOB community changed across growth stages in both cotton genotypes, and cotton genotype was the most important factor affecting the AOA community. In conclusion, the current findings indicated no adverse effect of GM cotton on functional microorganisms.},
}
@article {pmid27572439,
year = {2016},
author = {Needham, DM and Fuhrman, JA},
title = {Pronounced daily succession of phytoplankton, archaea and bacteria following a spring bloom.},
journal = {Nature microbiology},
volume = {1},
number = {},
pages = {16005},
pmid = {27572439},
issn = {2058-5276},
mesh = {Archaea/classification/genetics/*growth &amp; development ; Bacteria/classification/genetics/*growth &amp; development ; California ; Cluster Analysis ; DNA, Ribosomal/chemistry/genetics ; Eukaryota/classification/genetics/*growth &amp; development ; Phylogeny ; Phytoplankton/classification/genetics/*growth &amp; development ; RNA, Archaeal/genetics ; RNA, Bacterial/genetics ; RNA, Protozoan/genetics ; RNA, Ribosomal, 16S/genetics ; Seasons ; Seawater/*microbiology ; Sequence Analysis, DNA ; },
abstract = {Marine phytoplankton perform approximately half of global carbon fixation, with their blooms contributing disproportionately to carbon sequestration(1), and most phytoplankton production is ultimately consumed by heterotrophic prokaryotes(2). Therefore, phytoplankton and heterotrophic community dynamics are important in modelling carbon cycling and the impacts of global change(3). In a typical bloom, diatoms dominate initially, transitioning over several weeks to smaller and motile phytoplankton(4). Here, we show unexpected, rapid community variation from daily rRNA analysis of phytoplankton and prokaryotic community members following a bloom off southern California. Analysis of phytoplankton chloroplast 16S rRNA demonstrated ten different dominant phytoplankton over 18 days alone, including four taxa with animal toxin-producing strains. The dominant diatoms, flagellates and picophytoplankton varied dramatically in carbon export potential. Dominant prokaryotes also varied rapidly. Euryarchaea briefly became the most abundant organism, peaking over a few days to account for about 40% of prokaryotes. Phytoplankton and prokaryotic communities correlated better with each other than with environmental parameters. Extending beyond the traditional view of blooms being controlled primarily by physics and inorganic nutrients, these dynamics imply highly heterogeneous, continually changing conditions over time and/or space and suggest that interactions among microorganisms are critical in controlling plankton diversity, dynamics and fates.},
}
@article {pmid27572167,
year = {2016},
author = {Baker, BJ and Saw, JH and Lind, AE and Lazar, CS and Hinrichs, KU and Teske, AP and Ettema, TJ},
title = {Genomic inference of the metabolism of cosmopolitan subsurface Archaea, Hadesarchaea.},
journal = {Nature microbiology},
volume = {1},
number = {},
pages = {16002},
pmid = {27572167},
issn = {2058-5276},
mesh = {Ammonia/metabolism ; Archaea/classification/*genetics/*metabolism ; Carbon Monoxide/metabolism ; *Environmental Microbiology ; Estuaries ; Hot Springs ; Hydrogen/metabolism ; Metabolic Networks and Pathways/*genetics ; Nitrites/metabolism ; Oxidation-Reduction ; *Phylogeny ; Sequence Analysis, DNA ; },
abstract = {The subsurface biosphere is largely unexplored and contains a broad diversity of uncultured microbes(1). Despite being one of the few prokaryotic lineages that is cosmopolitan in both the terrestrial and marine subsurface(2-4), the physiological and ecological roles of SAGMEG (South-African Gold Mine Miscellaneous Euryarchaeal Group) Archaea are unknown. Here, we report the metabolic capabilities of this enigmatic group as inferred from genomic reconstructions. Four high-quality (63-90% complete) genomes were obtained from White Oak River estuary and Yellowstone National Park hot spring sediment metagenomes. Phylogenomic analyses place SAGMEG Archaea as a deeply rooting sister clade of the Thermococci, leading us to propose the name Hadesarchaea for this new Archaeal class. With an estimated genome size of around 1.5 Mbp, the genomes of Hadesarchaea are distinctly streamlined, yet metabolically versatile. They share several physiological mechanisms with strict anaerobic Euryarchaeota. Several metabolic characteristics make them successful in the subsurface, including genes involved in CO and H2 oxidation (or H2 production), with potential coupling to nitrite reduction to ammonia (DNRA). This first glimpse into the metabolic capabilities of these cosmopolitan Archaea suggests they are mediating key geochemical processes and are specialized for survival in the subsurface biosphere.},
}
@article {pmid27561235,
year = {2017},
author = {Zhu, Y and Sun, Y and Wang, C and Li, F},
title = {Impact of dietary fibre:starch ratio in shaping caecal archaea revealed in rabbits.},
journal = {Journal of animal physiology and animal nutrition},
volume = {101},
number = {4},
pages = {635-640},
doi = {10.1111/jpn.12585},
pmid = {27561235},
issn = {1439-0396},
mesh = {Animal Feed/analysis ; Animal Nutritional Physiological Phenomena ; Animals ; Archaea/genetics/*physiology ; Cecum/*