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18 Aug 2019 at 01:34
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Bibliography on: Microbiome


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RJR: Recommended Bibliography 18 Aug 2019 at 01:34 Created: 


It has long been known that every multicellular organism coexists with large prokaryotic ecosystems — microbiomes — that completely cover its surfaces, external and internal. Recent studies have shown that these associated microbiomes are not mere contamination, but instead have profound effects upon the function and fitness of the multicellular organism. We now know that all MCEs are actually functional composites, holobionts, composed of more prokaryotic cells than eukaryotic cells and expressing more prokaryotic genes than eukaryotic genes. A full understanding of the biology of "individual" eukaryotes will now depend on an understanding of their associated microbiomes.

Created with PubMed® Query: microbiome[tiab] NOT pmcbook NOT ispreviousversion

Citations The Papers (from PubMed®)

RevDate: 2019-08-16

Junkins EN, Speck M, DO Carter (2019)

The microbiology, pH, and oxidation reduction potential of larval masses in decomposing carcasses on Oahu, Hawaii.

Journal of forensic and legal medicine, 67:37-48 pii:S1752-928X(19)30086-1 [Epub ahead of print].

Previous studies have begun to characterize the microbial community dynamics of the skin, soil, gut, and oral cavities of decomposing remains. One area that has yet to be explored in great detail is the microbiome of the fly larval mass, the community of immature flies that plays a significant role in decomposition. The current study aimed to characterize the microbiology and chemistry of larval masses established on pig (Sus scrofa domesticus) carcasses and to determine if these characteristics have potential as temporal evidence. Carcasses (n = 3) were decomposed on the soil surface of a tropical habitat on Oahu, Hawaii, USA and sampled over three days at 74 h, 80 h, 98 h, 104 h, 122 h, and 128 h (∼85-142 Accumulated Degree Days) postmortem. Larval masses were analyzed via high-throughput 16S rRNA sequencing and in situ chemical measurements (pH, temperature, oxidation-reduction potential). A trend was observed that resulted in three distinct microbial communities (pre-98 h, 98 h, and post-98 h). The oxidation-reduction potential (Eh) of larval masses apparently regulated microbial community structure with the most negative Eh being associated with the least rich and diverse microbial communities. Overall, a significant interaction between time and taxa was observed, particularly with bacterial phyla Firmicutes and Proteobacteria. The current results provide new insight into the microbial community and chemical parameters of larval masses and indicate a temporal shift that could be further studied as a PMI estimator.

RevDate: 2019-08-16

Cox LM, Abou-El-Hassan H, Maghzi AH, et al (2019)

The sex-specific interaction of the microbiome in neurodegenerative diseases.

Brain research pii:S0006-8993(19)30439-1 [Epub ahead of print].

Several neurologic diseases exhibit different prevalence and severity in males and females, highlighting the importance of understanding the influence of biologic sex and gender. Beyond host-intrinsic differences in neurologic development and homeostasis, evidence is now emerging that the microbiota is an important environmental factor that may account for differences between men and women in neurologic disease. The gut microbiota is composed of trillions of bacteria, archaea, viruses, and fungi, that can confer benefits to the host or promote disease. There is bidirectional communication between the intestinal microbiota and the brain that is mediated via immunologic, endocrine, and neural signaling pathways. While there is substantial interindividual variation within the microbiota, differences between males and females can be detected. In animal models, sex-specific microbiota differences can affect susceptibility to chronic diseases. In this review, we discuss the ways in which neurologic diseases may be regulated by the microbiota in a sex-specific manner.

RevDate: 2019-08-16

Moreno-Arrones OM, Serrano-Villar S, Perez-Brocal V, et al (2019)

Analysis of the gut microbiota in alopecia areata: identification of bacterial biomarkers.

Journal of the European Academy of Dermatology and Venereology : JEADV [Epub ahead of print].

BACKGROUND: Alopecia areata is a T-cell-mediated autoimmune disease with an unknown etiopathogenesis. Gut microbiota has been revealed as a key modulator of systemic immunity.

OBJECTIVE: To determine if patients affected by alopecia universalis present differences in gut bacteria composition compared to healthy controls and investigate possible bacterial biomarkers of the disease.

METHODS: We conducted a cross-sectional study that involved 15 patients affected by alopecia universalis and 15 controls. Gut microbiome of the study subjects was analyzed by sequencing the 16SrRNA of stool samples. We searched for bacterial biomarkers of alopecia universalis using the linear discriminant analysis effect size (LEFse) tool.

RESULTS: In total, 30 study subjects (46.6% female; mean [SD] age, 40.1 [9.8] years) were enrolled. Neither alpha (Shannon diversity index 5.31 ± 0.43 vs. 5.03 ± 0.43, p 0.1) or beta diversity (ADONIS p value: 0.35) of gut microbiota showed statistically significant differences between cases and controls. In patients affected with alopecia, we found an enriched presence (LDA SCORE >2) of Holdemania filiformis, Erysipelotrichacea, Lachnospiraceae, Parabacteroides johnsonii, Clostridiales vadin BB60 group, Bacteroides eggerthii and Parabacteroides distasonis. A predictive model based on the number of bacterial counts of Parabacteroides distasonis and Clostridiales vadin BB60 group correctly predicted disease status in 80% of patients (AUC 0.804 (0.633 - 0.976), p 0.004).

CONCLUSION: Alopecia universalis does not seem to affect broadly gut microbiota structure. Bacterial biomarkers found associated with the disease (Holdemania filiformis, Erysipelotrichacea, Lachnospiraceae, Parabacteroides johnsonii, Eggerthellaceae, Clostridiales vadin BB60 group, Bacteroides eggerthii and Parabacteroides distasonis) should be further studied as they could be involved in its pathophysiology or be used as diagnostic tools. This article is protected by copyright. All rights reserved.

RevDate: 2019-08-16

Krieger Y, Horev A, Wainstock T, et al (2019)

Meconium stained amniotic fluid as a protective factor against childhood dermatitis and skin rash related hospitalization in the offspring - a population based cohort analysis.

Journal of the European Academy of Dermatology and Venereology : JEADV [Epub ahead of print].

BACKGROUND: Gut microbiome influences cutaneous diseases including atopic dermatitis. Possible impact of intrauterine exposure to meconium on the occurrence of dermatitis and skin rash was proposed.

OBJECTIVE: We investigated the possible influence of intrauterine exposure to meconium stained amniotic fluid (MSAF) on the occurrence of dermatitis and skin rash related hospitalizations throughout childhood.

METHODS: Singleton deliveries occurring between 1991-2014 at a single medical center were divided into two study groups based on presence or lack of MSAF during delivery. Population based cohort analysis, Kaplan-Meier survival analysis, and Cox proportional hazards model were used to study the association between MSAF and cutaneous morbidity related hospitalizations.

RESULTS: A lower rate of the total dermatitis or skin eruption related hospitalization was documented in the MSAF exposed group; 0.78 per 1,000-person years (0.9%, n=312), as compared to 0.98 per 1,000-person years in the unexposed group (1.0%, n=1992) with a hazard ratio of 0.86 (95%CI 0.76-0.96, p=0.011). The survival curve showed lower cumulative hospitalization rate in the MSAF exposed group as compared to the unexposed group (log rank p=0.01). The Cox analysis, controlled for confounders, demonstrated MSAF exposure to be an independent protective factor for dermatitis and skin rash related hospitalizations during childhood (adjusted HR 0.878 (95%CI 0.779-0.990, p=0.034).

CONCLUSION: Fetal exposure to MSAF appears to be an independent protective factor for dermatitis and skin rash related hospitalizations in the offspring throughout childhood and adolescence. This article is protected by copyright. All rights reserved.

RevDate: 2019-08-16

Kohne M, Li W, Zhu C, et al (2019)

Deuterium Kinetic Isotope Effects Resolve Low-Temperature Substrate Radical Reaction Pathways and Steps in B12-Dependent Ethanolamine Ammonia-Lyase.

Biochemistry [Epub ahead of print].

The first-order reaction kinetics of the cryotrapped 1,1,2,2-2H4-aminoethanol substrate radical intermediate state in the adenosylcobalamin (B12)-dependent ethanolamine ammonia-lyase (EAL) from Salmonella enterica serovar Typhimurium are measured over the range of 203-225 K by using time-resolved, full-spectrum electron paramagnetic resonance spectroscopy. The studies target the fundamental understanding of the mechanism of EAL, the signature enzyme in ethanolamine utilization metabolism associated with microbiome homeostasis and disease conditions in the human gut. Incorporation of 2H into the hydrogen transfer that follows the substrate radical rearrangement step in the substrate radical decay reaction sequence leads to an observed 1H/2H isotope effect of approximately 2 that preserves, with high fidelity, the idiosyncratic piecewise pattern of rate constant versus inverse temperature dependence that was previously reported for the 1H-labeled substrate, including a monoexponential regime (T ≥ 220 K) and two distinct biexponential regimes (T = 203-219 K). In the global kinetic model, reaction at ≥220 K proceeds from the substrate radical macrostate, S• , and at 203-219 K along parallel pathways from the two sequential microstates, S1 • and S2 • , that are distinguished by different protein configurations. Decay from S• , or S1 • and S2 • , is rate-determined by radical rearrangement (1H) or by contributions from both radical rearrangement and hydrogen transfer (2H). Non-native direct decay to products from S1 • is a consequence of the free energy barrier to the native S1 • → S2 • protein configurational transition. At physiological temperatures, this is averted by the fast protein configurational dynamics that guide the S1 • → S2 • transition.

RevDate: 2019-08-16

Zhao R, Huang R, Long H, et al (2019)

The dynamics of the oral microbiome and oral health among patients receiving clear aligner orthodontic treatment.

Oral diseases [Epub ahead of print].

OBJECTIVES: This 6-month prospective clinical study assessed the impacts of Invisalign appliances on the oral bacterial community and oral health of patients.

METHODS: Salivary samples were obtained from twenty-five adult patients receiving Invisalign aligner treatment before the treatment (Group B) and at a 6-month follow-up (Group P). The bacterial composition of each sample was determined using Illumina MiSeq sequencing of the bacterial 16S rRNA. Intra- and intergroup biodiversity was analyzed. Clinical periodontal parameters and daily oral hygiene habits were recorded.

RESULTS: Reduction of plaque, increased daily brushing frequency and decreased dessert intake were observed in Group P compared to in Group B. 1,853,952 valid reads were obtained from the 50 salivary samples, with 37,904 sequences per sample. No significant differences were detected in the intra- and intergroup biodiversity comparisons between the two groups. By clustering, 8885 OTUs were identified and categorized into six major phyla: Firmicutes, Proteobacteria, Bacteroidetes, Fusobacteria, Actinobacteria and Candidate_division_TM7_norank. At the genus level, compared with Group B, Group P demonstrated significantly increased Bacillus abundance and decreased Prevotella abundance.

CONCLUSIONS: Our results suggested that the general biodiversity and salivary microbial community structure did not change significantly and that patients had increased beneficial oral hygiene habits and awareness during the first six months of Invisalign treatment. Hence, on the basis of this study, it appears that Invisalign aligner treatment did not induce deterioration of oral health nor significant biodiversity changes in oral bacterial communities, assuming that detailed oral hygiene instructions for both teeth and aligners were provided. This article is protected by copyright. All rights reserved.

RevDate: 2019-08-16

Mogilevski T, Burgell R, Aziz Q, et al (2019)

Review article: the role of the autonomic nervous system in the pathogenesis and therapy of IBD.

Alimentary pharmacology & therapeutics [Epub ahead of print].

BACKGROUND: There is a growing body of evidence implicating a role for the brain-gut axis in the pathogenesis of inflammation in patients with IBD.

AIMS: To perform a narrative review of published literature regarding the association of the autonomic nervous system and intestinal inflammation and to describe the rationale for and emerging use of autonomic manipulation as a therapeutic agent METHODS: Current relevant literature was summarised and critically examined.

RESULTS: There is substantial pre-clinical and clinical evidence for a multifaceted anti-inflammatory effect of the vagus at both systemic and local intestinal levels. It acts via acetylcholine-mediated activation of α-7-acetylcholine receptors involving multiple cell types in innate and adaptive immunity and the enteric nervous system with subsequent protective influences on the intestinal barrier, inflammatory mechanisms and the microbiome. In patients with IBD, there is evidence for a sympatho-vagal imbalance, functional enteric neuronal depletion and hyporeactivity of the hypothalamic-pituitary-adrenal axis. Direct or transcutaneous vagal neuromodulation up-regulates the cholinergic anti-inflammatory pathway in pre-clinical and clinical models with down-regulation of systemic and local intestinal inflammation. This is supported by two small studies in Crohn's disease although remains to be investigated in ulcerative colitis.

CONCLUSIONS: Modulating the cholinergic anti-inflammatory pathway influences inflammation both systemically and at a local intestinal level. It represents a potentially underutilised anti-inflammatory therapeutic strategy. Given the likely pathogenic role of the autonomic nervous system in patients with IBD, vagal neuromodulation, an apparently safe and successful means of increasing vagal tone, warrants further clinical exploration.

RevDate: 2019-08-16

Eisenhauer L, Vahjen W, Dadi T, et al (2019)

Effects of brewer's spent grain and carrot pomace on digestibility, fecal microbiota, and fecal and urinary metabolites in dogs fed low or high protein diets.

Journal of animal science pii:5550707 [Epub ahead of print].

Brewer's spent grain (BSG) and carrot pomace (CAP) were used as fiber sources in low or high protein diets in dogs. Ten adult Beagles were involved in five feeding periods of 19 days in a cross-over design. Experimental diets contained 7.5 % of total dietary fiber from BSG or CAP and 20 % or 40 % of crude protein in dry matter. A diet with 3.5 % total dietary fiber from both fiber sources and 20 % crude protein was used as reference. Fecal dry matter was 27 % higher for diets with BSG compared to CAP (P < 0.001). Apparent fecal digestibility of crude protein was 7-11 % higher in diets with 40 % protein concentration (P < 0.001), while apparent digestibility of crude fat was 2-3 % higher for diets with CAP (P < 0.001). CAP increased the apparent fecal digestibility of total dietary fiber, phosphorus and magnesium (p<0.001), while 40 % protein diets had a positive impact on total dietary fiber and sodium and a negative effect on magnesium apparent fecal digestibility (p<0.001). Inclusion of CAP increased fecal short chain fatty acids (P = 0.010), mainly acetate (P = 0.001). I-butyrate (P = 0.001), i-valerate (P = 0.002), biogenic amines (P < 0.001) and ammonium (P < 0.001) increased with higher dietary protein levels. Diet induced changes in the fecal microbiome were moderate. Relative abundance of Bifidobacteriales was higher for the low protein diets (P = 0.001). To conclude, BSG and CAP can be used as fiber sources in canine diets and are well tolerated even at higher inclusion rates, the effect on microbial protein fermentation seems to be limited compared to the dietary protein level.

RevDate: 2019-08-16

Buccheri MA, Salvo E, Coci M, et al (2019)

Investigating microbial indicators of anthropogenic marine pollution by 16S and 18S High Throughput Sequencing (HTS) library analysis.

FEMS microbiology letters pii:5550730 [Epub ahead of print].

High Throughput Sequencing technologies are providing unprecedented inventories of microbial communities in aquatic samples, offering an invaluable tool to estimate the impact of anthropogenic pressure on marine communities. In this case study, the Mediterranean touristic site of Aci Castello (Italy) was investigated by High Throughput Sequencing of 16S and 18S rRNA genes. The sampling area falls within a Marine Protected Area and, notwithstanding, features an untreated urban wastewater discharge. Seawater samples were collected close to the wastewater output (COL) and at a second station about 400 m further off (PAN), before and after a summer increase in population. Prokaryotic communities clustered according to stations, rather than to seasons. While PAN showed a typical, not impacted, marine microbial composition, COL was consistently enriched in Epsilonproteobacteria and Firmicutes. Protist communities showed a peculiar clustering, as COL at springtime stood-alone and was dominated by Ciliophora, while the other samples were enriched in Dinophyta. Analysis of alternative, detectable by High Throughput Sequencing, microbial indicators, including both faecal- and sewage associated, allowed uncovering the different sources of pollution in coastal and anthropogenically-impacted marine ecosystems, underpinning the relevance of High Throughput Sequencing -based screening as rapid and precise method for water quality management.

RevDate: 2019-08-16

Jones NP (2019)

Immunosuppression in the Management of Presumed Non-infective Uveitis; Are We Sure What We are Treating? Notes on the Antimicrobial Properties of the Systemic Immunosuppressants.

Ocular immunology and inflammation [Epub ahead of print].

Purpose: To describe the antimicrobial effects of immunosuppressants used for presumed autoimmune uveitis, and to discuss the potential importance of these effects in the context of increasing knowledge of the human microbiomes and their influence on inflammation. Methods: Literature review Review of evidence: All immunosuppressants have intrinsic antimicrobial effects; these vary considerably between drugs, and include antibacterial, antiviral and antifungal action. Immunosuppression is known to affect the composition of the gut microbiome, and alterations in microbiome composition are known to affect inflammations including uveitis. Conclusions: Oral immunosuppressants are assumed to act on presumed autoimmune uveitis by downregulation of, or other interference with, an aberrant immune response. However, their antimicrobial properties are usually forgotten, and in the context of increasing knowledge of the involvement of microbes in the initiation of, and also potentially the perpetuation of, tissue inflammation, these effects may prove to be a fundamental part of their action.

RevDate: 2019-08-16

Ramayo-Caldas Y, Zingaretti L, Popova M, et al (2019)

Identification of rumen microbial biomarkers linked to methane emission in Holstein dairy cows.

Journal of animal breeding and genetics = Zeitschrift fur Tierzuchtung und Zuchtungsbiologie [Epub ahead of print].

Mitigation of greenhouse gas emissions is relevant for reducing the environmental impact of ruminant production. In this study, the rumen microbiome from Holstein cows was characterized through a combination of 16S rRNA gene and shotgun metagenomic sequencing. Methane production (CH4) and dry matter intake (DMI) were individually measured over 4-6 weeks to calculate the CH4 yield (CH4 y = CH4 /DMI) per cow. We implemented a combination of clustering, multivariate and mixed model analyses to identify a set of operational taxonomic unit (OTU) jointly associated with CH4 y and the structure of ruminal microbial communities. Three ruminotype clusters (R1, R2 and R3) were identified, and R2 was associated with higher CH4 y. The taxonomic composition on R2 had lower abundance of Succinivibrionaceae and Methanosphaera, and higher abundance of Ruminococcaceae, Christensenellaceae and Lachnospiraceae. Metagenomic data confirmed the lower abundance of Succinivibrionaceae and Methanosphaera in R2 and identified genera (Fibrobacter and unclassified Bacteroidales) not highlighted by metataxonomic analysis. In addition, the functional metagenomic analysis revealed that samples classified in cluster R2 were overrepresented by genes coding for KEGG modules associated with methanogenesis, including a significant relative abundance of the methyl-coenzyme M reductase enzyme. Based on the cluster assignment, we applied a sparse partial least-squares discriminant analysis at the taxonomic and functional levels. In addition, we implemented a sPLS regression model using the phenotypic variation of CH4 y. By combining these two approaches, we identified 86 discriminant bacterial OTUs, notably including families linked to CH4 emission such as Succinivibrionaceae, Ruminococcaceae, Christensenellaceae, Lachnospiraceae and Rikenellaceae. These selected OTUs explained 24% of the CH4 y phenotypic variance, whereas the host genome contribution was ~14%. In summary, we identified rumen microbial biomarkers associated with the methane production of dairy cows; these biomarkers could be used for targeted methane-reduction selection programmes in the dairy cattle industry provided they are heritable.

RevDate: 2019-08-16

Yang XX, Zhang L, Huang XQ, et al (2019)

[Difference of the microbial community structure in the rhizosphere of soybean and oilseed rape based on high-throughput pyrosequencing analysis.].

Ying yong sheng tai xue bao = The journal of applied ecology, 30(7):2345-2351.

Clubroot, caused by the soil-borne obligate pathogen Plasmodiophora brassicae, is one of the most severe disease in cruciferous crops. Previous studies showed that when oilseed rape was planted after soybean (namely soybean-oilseed rotation), the incidence and severity of clubroot of oilseed rape could be significantly reduced, compared with that with oilseed rape-oilseed rape conti-nuous cropping. Therefore, the soybean-oilseed rape rotation is a good way to suppress clubroot of oilseed rape. In this study, we compared the rhizosphere microbiome of soybean and oilseed rape rhizosphere soil collected from the field by 16S rRNA (for identification of prokaryotes) and the internal transcribed spacer (ITS) (for identification of fungi) sequencing. The results showed that both soybean and oilseed rape rhizosphere soils had Proteobacteria, Bacteroidetes, Acidobacteria, Actinobacteria, Ascomycota, Zygomycota, Basidiomycota and Chytridiomycota. Many microbial genera (e.g., Flavobacterium, Sphingomonas, Bacillus, Streptomyces, Pseudomonas, Trichoderma and Coniothyrium) with activities of biological control and plant growth promotion were more abundant in soybean rhizosphere soil than in the oilseed rape rhizosphere soil. The abundance of plant pathogenic bacteria and fungi was higher in the oilseed rape rhizosphere soil than in the soybean rhizosphere soil. Moreover, the soybean rhizosphere soil was enriched with Rhizobium, Bradyrhizobium (both for nitrogen fixation), and arbuscular mycorrhizal fungus (Glomus). These results indicated that soybean rhizosphere soil could promote the growth and proliferation of beneficial microorga-nisms, but inhibit that of plant pathogens. Our results provide evidence for explanation of the effectiveness of soybean-oilseed rape rotation to control clubroot of oilseed rape and provide potential bio-control resources for clubroot prevention.

RevDate: 2019-08-16

Allen JM, Jaggers RM, Solden LM, et al (2019)

Dietary Oligosaccharides Attenuate Stress-Induced Disruptions in Immune Reactivity and Microbial B-Vitamin Metabolism.

Frontiers in immunology, 10:1774.

Background: Exposure to stressful stimuli dysregulates inflammatory processes and alters the gut microbiota. Prebiotics, including long-chain fermentable fibers and milk oligosaccharides, have the potential to limit inflammation through modulation of the gut microbiota. To determine whether prebiotics attenuate stress-induced inflammation and microbiota perturbations, mice were fed either a control diet or a diet supplemented with galactooligosaccharides, polydextrose and sialyllactose (GOS+PDX+SL) or sialyllactose (SL) for 2 weeks prior to and during a 6-day exposure to a social disruption stressor. Spleens were collected for immunoreactivity assays. Colon contents were examined for stressor- and diet- induced changes in the gut microbiome and metabolome through 16S rRNA gene sequencing, shotgun metagenomic sequencing and UPLC-MS/MS. Results: Stress increased circulating IL-6 and enhanced splenocyte immunoreactivity to an ex vivo LPS challenge. Diets containing GOS+PDX+SL or SL alone attenuated these responses. Stress exposure resulted in large changes to the gut metabolome, including robust shifts in amino acids, peptides, nucleotides/nucleosides, tryptophan metabolites, and B vitamins. Multiple B vitamins were inversely associated with IL-6 and were augmented in mice fed either GOS+PDX+SL or SL diets. Stressed mice exhibited distinct microbial communities with lower abundances of Lactobacillus spp. and higher abundances of Bacteroides spp. Diet supplementation with GOS+PDX+SL, but not SL alone, orthogonally altered the microbiome and enhanced the growth of Bifidobacterium spp. Metagenome-assembled genomes (MAGs) from mice fed the GOS+PDX+SL diet unveiled genes in a Bifidobacterium MAG for de novo B vitamin synthesis. B vitamers directly attenuated the stressor-induced exacerbation of cytokine production in LPS-stimulated splenocytes. Conclusions: Overall, these data indicate that colonic metabolites, including B vitamins, are responsive to psychosocial stress. Dietary prebiotics reestablish colonic B vitamins and limit stress-induced inflammation.

RevDate: 2019-08-16

Conteville LC, Oliveira-Ferreira J, ACP Vicente (2019)

Gut Microbiome Biomarkers and Functional Diversity Within an Amazonian Semi-Nomadic Hunter-Gatherer Group.

Frontiers in microbiology, 10:1743.

Human groups that still maintain traditional modes of subsistence (hunter-gatherers and rural agriculturalists) represent human groups non-impacted by urban-industrialized lifestyles, and therefore their gut microbiome provides the basis for understanding the human microbiome evolution and its association with human health and disease. The Yanomami is the largest semi-nomadic hunter-gatherer group of the Americas, exploring different niches of the Amazon rainforest in Brazil and Venezuela. Here, based on shotgun metagenomic data, we characterized the gut microbiome of the Yanomami from Brazil and compared taxonomically and functionally with the Yanomami from Venezuela, with other traditional groups from the Amazon and an urban-industrialized group. Taxonomic biomarkers were identified to each South American traditional group studied, including each Yanomami group. Broader levels of functional categories poorly discriminated the traditional and urban-industrialized groups, but the stratification of these categories revealed clear segregation of these groups. The Yanomami/Brazil gut microbiome presented unique functional features, such as a higher abundance of gene families involved in regulation/cell signaling, motility/chemotaxis, and virulence, contrasting with the gut microbiomes from the Yanomami/Venezuela and the other groups. Our study revealed biomarkers, and taxonomic and functional features that distinguished the gut microbiome of Yanomami/Brazil and Yanomami/Venezuela individuals, despite their shared lifestyle, culture, and genetic background. These differences may be a reflection of the environmental and seasonal diversity of the niches they explore. Overall, their microbiome profiles are shared with South American and African traditional groups, probably due to their lifestyle. The unique features identified within the Yanomami highlight the bias imposed by underrepresented sampling, and factors such as variations over space and time (seasonality) that impact, mainly, the hunter-gatherers.

RevDate: 2019-08-16

Abbondio M, Palomba A, Tanca A, et al (2019)

Fecal Metaproteomic Analysis Reveals Unique Changes of the Gut Microbiome Functions After Consumption of Sourdough Carasau Bread.

Frontiers in microbiology, 10:1733.

Sourdough-leavened bread (SB) is acknowledged for its great variety of valuable effects on consumer's metabolism and health, including a low glycemic index and a reduced content of the possible carcinogen acrylamide. Here, we aimed to investigate how these effects influence the gut microbiota composition and functions. Therefore, we subjected rats to a diet supplemented with SB, baker's yeast leavened bread (BB), or unsupplemented diet (chow), and, after 4 weeks of treatment, their gut microbiota was analyzed using a metaproteogenomic approach. As a result, diet supplementation with SB led to a reduction of specific members of the intestinal microbiota previously associated to low protein diets, namely Alistipes and Mucispirillum, or known as intestinal pathobionts, i.e., Mycoplasma. Concerning functions, asparaginases expressed by Bacteroides were observed as more abundant in SB-fed rats, leading to hypothesize that in their colonic microbiota the enzyme substrate, asparagine, was available in higher amounts than in BB- and chow-fed rats. Another group of protein families, expressed by Clostridium, was detected as more abundant in animal fed SB-supplemented diet. Of these, manganese catalase, small acid-soluble proteins (SASP), Ser/Thr kinase PrkA, and V-ATPase proteolipid subunit have been all reported to take part in Clostridium sporulation, strongly suggesting that the diet supplementation with SB might promote environmental conditions inducing metabolic dormancy of Clostridium spp. within the gut microbiota. In conclusion, our data describe the effects of SB consumption on the intestinal microbiota taxonomy and functions in rats. Moreover, our results suggest that a metaproteogenomic approach can provide evidence of the interplay between metabolites deriving from bread digestion and microbial metabolism.

RevDate: 2019-08-16

Bravo M, Combes T, Martinez FO, et al (2019)

Lactobacilli Isolated From Wild Boar (Sus scrofa) Antagonize Mycobacterium bovis Bacille Calmette-Guerin (BCG) in a Species-Dependent Manner.

Frontiers in microbiology, 10:1663.

Background: Wildlife poses a significant burden for the complete eradication of bovine tuberculosis (bTB). In particular, wild boar (Sus scrofa) is one of the most important reservoirs of Mycobacterium bovis, the causal agent of bTB. Wild boar can display from mild TB lesions, usually found in head lymph nodes, to generalized TB lesions distributed in different anatomical regions; but rarely clinical signs, which complicates the diagnosis of Mycobacterium bovis infection and bTB control. Among the possibilities for this variability in lesion distribution is the influence of the host-beneficial commensal-primed immune barrier. In this respect, beneficial microbes may delay bTB dissemination as a consequence of an antagonistic competition for nutrients and phagocytes. In order to explore this possibility, we have tested whether typical commensals such as lactobacilli have the capacity to reduce the survival rate of the surrogate M. bovis strain Bacillus Calmette-Guerin (BCG); and to modulate its phagocyte intake. Results: Three Lactobacillus species, L. casei, L. plantarum, and L. salivarius, isolated from wild boar feces displayed a pH-dependent inhibitory activity against BCG and influenced its intake by porcine blood phagocytes in a species-dependent manner. All lactobacilli showed a very significant bactericidal effect against BCG at low pH, but only isolates of L. plantarum and L. casei displayed such antimycobacterial activity at neutral pH. The genomes of these isolates revealed the presence of two-peptide bacteriocins whose precursor genes up-regulate in the presence of BCG cells. Furthermore, L. plantarum reduced significantly the BCG phagocytic intake, whereas L. casei had the opposite effect. L. salivarius had no significant influence on the phagocytic response to BCG. Conclusions: Our in vitro results show that lactobacilli isolated from wild boar antagonize BCG as a consequence of their antimycobacterial activity and a competitive phagocytic response. These findings suggest that commensal bacteria could play a beneficial role in influencing the outcome of bTB dissemination. Further work with lactobacilli as a potential competitive pressure to control bTB will need to take into account the complex nature of the commensal microbiome, the specific immunity of the wild boar and the in vivo infection context with pathogenic strains of M. bovis.

RevDate: 2019-08-16

Sudo N (2019)

Biogenic Amines: Signals Between Commensal Microbiota and Gut Physiology.

Frontiers in endocrinology, 10:504.

There is increasing interest in the interactions among the gut microbiota, gut, and brain, which is often referred to as the "microbiota-gut-brain" axis. Biogenic amines including dopamine, norepinephrine, serotonin, and histamines are all generated by commensal gut microorganisms and are suggested to play roles as signaling molecules mediating the function of the "microbiota-gut-brain" axis. In addition, such amines generated in the gut have attracted attention in terms of possible clues into the etiologies of depression, anxiety, and even psychosis. This review covers the latest research related to the potential role of microbe-derived amines such as catecholamine, serotonin, histamine, as well as other trace amines, in modulating not only gut physiology but also brain function of the host. Further attention in this field can offer not only insight into expanding the fundamental roles and impacts of the human microbiome, but also further offer new therapeutic strategies for psychological disorders based on regulating the balance of resident bacteria.

RevDate: 2019-08-16

Lacorte E, Gervasi G, Bacigalupo I, et al (2019)

A Systematic Review of the Microbiome in Children With Neurodevelopmental Disorders.

Frontiers in neurology, 10:727.

Background and Purpose: A relationship between gut microbiome and central nervous system (CNS), have been suggested. The human microbiome may have an influence on brain's development, thus implying that dysbiosis may contribute in the etiology and progression of some neurological/neuropsychiatric disorders. The objective of this systematic review was to identify evidence on the characterization and potential distinctive traits of the microbiome of children with neurodevelopmental disorders, as compared to healthy children. Methods: The review was performed following the methodology described in the Cochrane handbook for systematic reviews, and was reported based on the PRISMA statement for reporting systematic reviews and meta-analyses. All literature published up to April 2019 was retrieved searching the databases PubMed, ISI Web of Science and the Cochrane Database of Systematic Reviews. Only observational studies, published in English and reporting data on the characterization of the microbiome in humans aged 0-18 years with a neurodevelopmental disorder were included. Neurodevelopmental disorders were categorized according to the definition included in the Diagnostic and Statistical Manual of Mental Disorders, version 5 (DSM-5). Results: Bibliographic searches yielded 9,237 records. One study was identified through other data sources. A total of 16 studies were selected based on their relevance and pertinence to the topic of the review, and were then applied the predefined inclusion and exclusion criteria. A total of 10 case-control studies met the inclusion criteria, and were thus included in the qualitative analysis and applied the NOS score. Two studies reported data on the gut microbiome of children with ADHD, while 8 reported data on either the gut (n = 6) or the oral microbiome (n = 2) of children with ASD. Conclusions: All the 10 studies included in this review showed a high heterogeneity in terms of sample size, gender, clinical issues, and type of controls. This high heterogeneity, along with the small sample size of the included studies, strongly limited the external validity of results. The quality assessment performed using the NOS score showed an overall low to moderate methodological quality of the included studies. To better clarify the potential role of microbiome in patients with neurodevelopmental disorders, further high-quality observational (specifically cohort) studies are needed.

RevDate: 2019-08-16

Douglas AE (2019)

Simple animal models for microbiome research.

Nature reviews. Microbiology pii:10.1038/s41579-019-0242-1 [Epub ahead of print].

The health and fitness of animals, including humans, are influenced by the presence and composition of resident microbial communities. The development of rational microbial therapies to alleviate chronic immunological, metabolic and neurobiological diseases requires an understanding of the processes underlying microbial community assembly and the mechanisms by which microorganisms influence host traits. For fundamental discovery, simple animal models (that is, lower vertebrate and invertebrate species with low diversity microbiomes) are more cost-effective and time-efficient than mammal models, especially for complex experimental designs and sophisticated genetic screens. Recent research on these simple models demonstrates how microbiome composition is shaped by the interplay between host controls, mediated largely via immune effectors, inter-microorganism competition, and neutral processes of passive dispersal and ecological drift. Parallel research on microbiome-dependent host traits has identified how specific metabolites and proteins released from microorganisms can shape host immune responsiveness, ameliorate metabolic dysfunction and influence behavioural traits. In this Review, the opportunity for microbiome research on the traditional biomedical models zebrafish, Drosophila melanogaster and Caenorhabditis elegans, which command superb research resources and tools, is discussed. Other systems, for example, hydra, squid and the honeybee, are valuable alternative models to address specific questions.

RevDate: 2019-08-16

Rosenthal SB, Bush KT, SK Nigam (2019)

A Network of SLC and ABC Transporter and DME Genes Involved in Remote Sensing and Signaling in the Gut-Liver-Kidney Axis.

Scientific reports, 9(1):11879 pii:10.1038/s41598-019-47798-x.

Genes central to drug absorption, distribution, metabolism and elimination (ADME) also regulate numerous endogenous molecules. The Remote Sensing and Signaling Hypothesis argues that an ADME gene-centered network-including SLC and ABC "drug" transporters, "drug" metabolizing enzymes (DMEs), and regulatory genes-is essential for inter-organ communication via metabolites, signaling molecules, antioxidants, gut microbiome products, uremic solutes, and uremic toxins. By cross-tissue co-expression network analysis, the gut, liver, and kidney (GLK) formed highly connected tissue-specific clusters of SLC transporters, ABC transporters, and DMEs. SLC22, SLC25 and SLC35 families were network hubs, having more inter-organ and intra-organ connections than other families. Analysis of the GLK network revealed key physiological pathways (e.g., involving bile acids and uric acid). A search for additional genes interacting with the network identified HNF4α, HNF1α, and PXR. Knockout gene expression data confirmed ~60-70% of predictions of ADME gene regulation by these transcription factors. Using the GLK network and known ADME genes, we built a tentative gut-liver-kidney "remote sensing and signaling network" consisting of SLC and ABC transporters, as well as DMEs and regulatory proteins. Together with protein-protein interactions to prioritize likely functional connections, this network suggests how multi-specificity combines with oligo-specificity and mono-specificity to regulate homeostasis of numerous endogenous small molecules.

RevDate: 2019-08-16

Shiels PG, Buchanan S, Selman C, et al (2019)

Allostatic load and ageing: linking the microbiome and nutrition with age-related health.

Biochemical Society transactions pii:BST20190110 [Epub ahead of print].

Ageing is a process of decline in physiological function and capability over time. It is an anticipated major burden on societal health-care costs due to an increasingly aged global population. Accelerated biological ageing is a feature of age-related morbidities, which also appear to share common underpinning features, including low-grade persistent inflammation, phosphate toxicity, diminished Nrf2 activity, a depleted metabolic capability, depressed mitochondrial biogenesis and a low diversity gut microbiome.Social, psychological, lifestyle and nutritional risk factors can all influence the trajectory of age-related health, as part of an individual's exposome, which reflects the interplay between the genome and the environment. This is manifest as allostatic (over)load reflecting the burden of lifestyle/disease at both a physiological and molecular level. In particular, age-related genomic methylation levels and inflammatory status reflect exposome differences. These features may be mediated by changes in microbial diversity. This can drive the generation of pro-inflammatory factors, such as TMAO, implicated in the 'diseasome' of ageing. Additionally, it can be influenced by the 'foodome', via nutritional differences affecting the availability of methyl donors required for maintenance of the epigenome and by the provision of nutritionally derived Nrf2 agonists. Both these factors influence age-related physiological resilience and health. This offers novel insights into possible interventions to improve health span, including a rage of emerging senotherapies and simple modifications of the nutritional and environmental exposome. In essence, the emerging strategy is to treat ageing processes common to the diseasome of ageing itself and thus preempt the development or progression of a range of age-related morbidities.

RevDate: 2019-08-16

Chen Y, Brook TC, Alcon-Giner C, et al (2019)

Draft Genome Sequence of Raoultella ornithinolytica P079F W, Isolated from the Feces of a Preterm Infant.

Microbiology resource announcements, 8(33): pii:8/33/e00493-19.

Here, we describe the draft genome sequence of Raoultella ornithinolytica P079F W, isolated from the feces of an infant residing in a neonatal intensive care unit during an ongoing study to characterize the neonate gut microbiota. P079F W will be used in studies investigating the role of the microbiome in neonatal infections.

RevDate: 2019-08-16

Rogers GB, Taylor SL, Hoffman LR, et al (2019)

The impact of CFTR modulator therapies on CF airway microbiology.

Journal of cystic fibrosis : official journal of the European Cystic Fibrosis Society pii:S1569-1993(19)30829-X [Epub ahead of print].

Major historical advances in cystic fibrosis (CF) respiratory clinical care, including mechanical airway clearance and inhaled medications, have aimed to address the consequences of cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction. In contrast, CFTR modulator therapies instead target the underlying protein defect that leads to CF lung disease. The extent to which these therapies might reduce susceptibility to chronic lung infections remains to be seen. However, by improving airway clearance, reducing the requirement for antibiotics, and in some cases, through direct antimicrobial effects, CFTR modulators are likely to result in substantial changes in CF airway microbiology. These changes could contribute substantially to the clinical benefit associated with modulator therapies, as well as providing an important indicator of treatment efficacy and residual pathophysiology. Indeed, the widespread introduction of modulator therapies might require us to re-consider our models of CF airway microbiology.

RevDate: 2019-08-16

Hakimian JK, Dong TS, Barahona JA, et al (2019)

Dietary Supplementation with Omega-3 Polyunsaturated Fatty Acids Reduces Opioid-Seeking Behaviors and Alters the Gut Microbiome.

Nutrients, 11(8): pii:nu11081900.

Opioids are highly addictive substances with a relapse rate of over 90%. While preclinical models of chronic opioid exposure exist for studying opioid dependence, none recapitulate the relapses observed in human opioid addiction. The mechanisms associated with opioid dependence, the accompanying withdrawal symptoms, and the relapses that are often observed months or years after opioid dependence are poorly understood. Therefore, we developed a novel model of chronic opioid exposure whereby the level of administration is self-directed with periods of behavior acquisition, maintenance, and then extinction alternating with reinstatement. This profile arguably mirrors that seen in humans, with initial opioid use followed by alternating periods of abstinence and relapse. Recent evidence suggests that dietary interventions that reduce inflammation, including omega-3 polyunsaturated fatty acids (n-3 PUFAs), may reduce substance misuse liability. Using the self-directed intake model, we characterize the observed profile of opioid use and demonstrate that an n-3-PUFA-enriched diet ameliorates oxycodone-seeking behaviors in the absence of drug availability and reduces anxiety. Guided by the major role gut microbiota have on brain function, neuropathology, and anxiety, we profile the microbiome composition and the effects of chronic opioid exposure and n-3 PUFA supplementation. We demonstrate that the withdrawal of opioids led to a significant depletion in specific microbiota genera, whereas n-3 PUFA supplementation increased microbial richness, phylogenetic diversity, and evenness. Lastly, we examined the activation state of microglia in the striatum and found that n-3 PUFA supplementation reduced the basal activation state of microglia. These preclinical data suggest that a diet enriched in n-3 PUFAs could be used as a treatment to alleviate anxiety induced opioid-seeking behavior and relapse in human opioid addiction.

RevDate: 2019-08-16

Cavuoto KM, Galor A, S Banerjee (2019)

Anatomic Characterization of the Ocular Surface Microbiome in Children.

Microorganisms, 7(8): pii:microorganisms7080259.

The microbiome is important in the evolution of the immune system in children; however, information is lacking regarding the composition of the pediatric ocular microbiome and its surrounding structures. A prospective, cross-sectional study of the ocular microbiome was conducted in children <18 years old. Samples from the inferior conjunctival fornix of both eyes, eyelid margin, and periocular skin underwent DNA amplification and 16S sequencing using Illumina MiSeq 250. The microbiome was analyzed using Qiime. Statistical analysis was performed using a two-sided Student's t-test, diversity indices, and principal coordinate analysis. A total of 15 children were enrolled. The ocular surface microbiome was predominantly composed of Proteobacteria, whereas Bacteroidetes dominated the eyelid margin, and Firmicutes dominated the periocular skin. Despite these variations, no statistically significant compositional differences were found with Bray-Curtis analysis. The conjunctiva had the lowest Shannon diversity index with a value of 2.3, which was significantly lower than those of the eyelid margin (3.4, p = 0.01) and the periocular skin (3.5, p = 0.001). However, the evenness of the species using Faith's phylogenetic diversity index was similar at all sites. Overall, the ocular surface microbiome is dominated by Proteobacteria in children. The niche is similar to the surrounding structures in terms of composition, but has a lower number and relative abundance of species.

RevDate: 2019-08-16

Sharma M, Krammer F, García-Sastre A, et al (2019)

Moving from Empirical to Rational Vaccine Design in the 'Omics' Era.

Vaccines, 7(3): pii:vaccines7030089.

An ideal vaccine provides long lasting protection against a pathogen by eliciting a well-rounded immune response which engages both innate and adaptive immunity. However, we have a limited understanding of how components of innate immunity, antibody and cell-mediated adaptive immunity interact and function together at a systems level. With advances in high-throughput 'Omics' methodologies it has become possible to capture global changes in the host, at a cellular and molecular level, that are induced by vaccination and infection. Analysis of these datasets has shown the promise of discovering mechanisms behind vaccine mediated protection, immunological memory, adverse effects as well as development of more efficient antigens and adjuvants. In this review, we will discuss how systems vaccinology takes advantage of new technology platforms and big data analysis, to enable the rational development of better vaccines.

RevDate: 2019-08-15

Sturød K, Dhariwal A, Dahle UR, et al (2019)

Impact of narrow spectrum Penicillin V on the oral and fecal resistome in a young child treated for otitis media.

Journal of global antimicrobial resistance pii:S2213-7165(19)30202-4 [Epub ahead of print].

BACKGROUND: Antibiotic overuse has led to a global emergence of resistant bacteria, and children are among the frequent users. Most studies with broad-spectrum antibiotics show severe impact on the resistome development of patients. Although narrow-spectrum antibiotics are believed to have less side-effects, their impact on the microbiome and resistome is mostly unknown. The aim of this study was to investigate the impact of the narrow-spectrum antibiotic phenoxymethylpenicillin (Penicillin V) on the microbiome and resistome of a child treated for acute otitis media (OM).

METHODS: Oral and fecal samples were collected from a one-year child before (day 0) and after (day 5 and 30) receiving Penicillin V against OM. Metagenomic sequencing data was analysed to determine taxonomic profiling, using Kraken and Bracken software, and resistance profiling, using KMA in combination with the ResFinder database.

RESULTS: In the oral samples, antimicrobial resistance genes (ARGs) belonging to four classes were identified at baseline. At day 5, the abundance of some ARGs was increased; some remained unchanged, while others disappeared. At day 30, most ARGs had returned to baseline levels, or lower. In the fecal samples, we observed seven ARGs at baseline and five at day 5. At day 30, the number increased to 21 ARGs from seven different classes.

CONCLUSIONS: Penicillin V had a remarkable impact on the fecal resistome indicating that even narrow-spectrum antibiotics may have important consequences in selecting for a more resistant microbiome.

RevDate: 2019-08-15

Tierney BT, Yang Z, Luber JM, et al (2019)

The Landscape of Genetic Content in the Gut and Oral Human Microbiome.

Cell host & microbe, 26(2):283-295.e8.

Despite substantial interest in the species diversity of the human microbiome and its role in disease, the scale of its genetic diversity, which is fundamental to deciphering human-microbe interactions, has not been quantified. Here, we conducted a cross-study meta-analysis of metagenomes from two human body niches, the mouth and gut, covering 3,655 samples from 13 studies. We found staggering genetic heterogeneity in the dataset, identifying a total of 45,666,334 non-redundant genes (23,961,508 oral and 22,254,436 gut) at the 95% identity level. Fifty percent of all genes were "singletons," or unique to a single metagenomic sample. Singletons were enriched for different functions (compared with non-singletons) and arose from sub-population-specific microbial strains. Overall, these results provide potential bases for the unexplained heterogeneity observed in microbiome-derived human phenotypes. One the basis of these data, we built a resource, which can be accessed at https://microbial-genes.bio.

RevDate: 2019-08-15

Pandey S, Maharana J, AK Shukla (2019)

The Gut Feeling: GPCRs Enlighten the Way.

Cell host & microbe, 26(2):160-162.

Host-microbiome interactions affect host physiology, but the underlying mechanisms are not well understood. Recent papers from Chen et al. (2019) and Colosimo et al. (2019) in this issue of Cell Host & Microbe demonstrate that metabolites produced by several members of the gut microbiota can efficiently activate host G protein-coupled receptors and influence host physiology.

RevDate: 2019-08-15

Poole AC (2019)

In the Grand Scheme of Things: Identifying Reproducible Microbial Signatures in Dietary Intervention Studies.

Cell host & microbe, 26(2):158-159.

Nutrition research is plagued by the reproducibility crisis. Reconciling nutrition studies involving microbiome data presents a modern challenge for researchers. In this issue of Cell Host & Microbe, Bisanz et al., 2019 demonstrate a comprehensive methodology for meta-analysis of microbiome sequence data from high-fat-diet intervention studies.

RevDate: 2019-08-15

Ross CM (2019)

Letter by Ross Regarding Article, "The Microbiome, Plasma Metabolites, Dietary Habits, and Cardiovascular Risk Unravelling Their Interplay".

Circulation research, 125(5):e27.

RevDate: 2019-08-15

Simon-Soro A, Sohn MB, McGinniss JE, et al (2019)

Upper Respiratory Dysbiosis with a Facultative-Dominated Ecotype in Advanced Lung Disease and Dynamic Change after Lung Transplant.

Annals of the American Thoracic Society [Epub ahead of print].

RATIONALE: The oropharyngeal microbiome is a primary source of lung microbiota and contributes to lower respiratory infection, and is also a driver of oral health.

OBJECTIVES: We sought to understand oropharyngeal microbial communities in advanced lung disease, community dynamics following lung transplantation, and ecological features of dysbiosis.

METHODS: Oropharyngeal wash (OW) samples were obtained from individuals with end-stage disease awaiting transplantation (n=22), and longitudinally from individuals at 6 weeks, 3 months and 6 months following transplantation (n=33), along with healthy controls (n=14). Bacterial 16S and fungal ITS rRNA regions were deep-sequenced, and bacterial community respiratory patterns were imputed from taxonomic composition.

RESULTS: Healthy subjects' oropharyngeal microbiomes showed a gradient of community types reflecting relative enrichment of strictly anaerobic, aerobic or facultative anaerobic bacteria. End-stage lung disease patients showed severe dysbiosis by both taxonomic composition and respiration phenotypes, with reduced richness and diversity, increased facultative and decreased aerobic bacteria, and absence of communities characterized by obligate aerobes. In patients at 6 weeks and 3 months post-transplant, richness and diversity were intermediate between healthy and pre-transplant subjects, with near-normal distribution of community types. However by six months post-transplant OW resembled the low-diversity facultative-dominated profile of pre-transplant subjects. Community ecotype correlated with Candida abundance.

CONCLUSIONS: End-stage lung disease is associated with marked upper respiratory tract dysbiosis involving both community structure and respiratory metabolism profiles of constituent bacteria. Dynamic changes occur after lung transplantation, with partial normalization early but later appearance of severe dysbiosis similar pre-transplant patients. Aberrant oropharyngeal communities may predispose to abnormal lung microbiota and infection risk both in advanced lung disease and after transplantation.

RevDate: 2019-08-15

van de Wouw M, Stilling RM, Peterson VL, et al (2019)

Host Microbiota Regulates Central Nervous System Serotonin Receptor 2C Editing in Rodents.

ACS chemical neuroscience [Epub ahead of print].

Microbial colonization of the gastrointestinal tract plays a crucial role in the development of enteric and central nervous system functionality. The serotonergic system has been heavily implicated in microbiota-gut-brain axis signaling, particularly in proof-of-principle studies in germ-free (GF) animals. One aspect of the serotonergic system that has been left unexplored in relation to the microbiota is the unique ability of the serotonin receptor 2c (5-HT2C) to undergo post-transcriptional editing, resulting in decreased receptor functionality. We investigated whether GF mice, with absent microbiota from birth, have altered 5-HT2C receptor expression and editing in the brain and if colonization of the microbiota is able to restore editing patterns. Next, we investigated whether microbiota depletion later in life using a chronic antibiotic treatment in rats could affect 5-HT2C receptor editing patterns. We found that GF mice have an increased prevalence of the edited 5-HT2C receptor isoforms in the amygdala, hypothalamus, prefrontal cortex and striatum, which was partially normalized upon colonization post-weaning. However, no alterations were observed in the hypothalamus after microbiota depletion using an antibiotic treatment in adult rats. This suggests that alterations in the microbiome during development, but not later life, could influence 5-HT2C receptor editing patterns. Overall, these results demonstrate that the microbiota affects 5-HT2C receptor editing in the brain and may inform novel therapeutic strategies in conditions in which 5-HT2C receptor editing is altered, such as depression.

RevDate: 2019-08-15

Lemoine L, Verbeke M, Bernaerts K, et al (2019)

Impact of the inoculum composition on the structure of the total and active community and its performance in identically operated anaerobic reactors.

Applied microbiology and biotechnology pii:10.1007/s00253-019-10041-8 [Epub ahead of print].

Anaerobic digestion (AD) is a biological process that is acquiring increasing attention for both solid waste and wastewater treatment, as well as for the production of valuable chemicals. Despite the importance of the inoculum, the relationship between inoculum community composition, reactor performance, and reactor community composition remains vague. To understand the impact of the starting community on the composition and functioning of the AD microbiome, we studied three sets of biologically replicated AD reactors inoculated with different communities, but operated identically, targeting both total and active community compositions. All reactors performed highly similar regarding volatile fatty acid and methane production. The community analyses showed reproducible total and active community compositions in replicate reactors, indicating that particularly deterministic factors shaped the AD community. Moreover, strong variation in community composition between the differently seeded reactors was observed, indicating the role of inoculum composition in community shaping. In all three reactor sets, especially species that were low abundant or even not detected in the inoculum contributed to the reactor communities, supporting the importance of functional redundancy and high diversity in inocula used for AD seeding. The careful start-up of the AD process using initially low organic loading rates likely contributed to the successful assembly of initial low-abundance/rare species into a new cooperative AD community in the reactors.

RevDate: 2019-08-15

Hao H, Zhu L, HS Faden (2019)

The milk-based diet of infancy and the gut microbiome.

Gastroenterology report, 7(4):246-249.

The composition and the diversity of the gut microbiome play a major role in the health and well-being of humans beginning at birth. The impact of the diet on the structure and the function of the gut microbiome is evident by the changes in the gut microbiome concurrent with the transition from human milk to solid food. Complex oligosaccharides contained in milk are essential nutrients for commensal microbes in the infant gut. The most important commensal bacterium in the infant gut, bifidobacterium, requires α1, 2 fucosylated oligosaccharides for growth. Because not all humans are able to secrete α1, 2 fucosylated oligosaccharides into milk, the gut microbiome of infants and bifidobacteria, in particular, vary considerably between 'secretors' and 'non-secretors'. A paucity of α1, 2 fucosylated oligosaccharides and bifidobacteria in the gut of infants may be associated with poor health.

RevDate: 2019-08-15

Hara S, Matsuda M, K Minamisawa (2019)

Growth Stage-dependent Bacterial Communities in Soybean Plant Tissues: Methylorubrum Transiently Dominated in the Flowering Stage of the Soybean Shoot.

Microbes and environments [Epub ahead of print].

Plant-associated bacteria are critical for plant growth and health. However, the effects of plant growth stages on the bacterial community remain unclear. Analyses of the microbiome associated with field-grown soybean revealed a marked shift in the bacterial community during the growth stages. The relative abundance of Methylorubrum in the leaf and stem increased from 0.2% to more than 45%, but decreased to approximately 15%, with a peak at the flowering stage at which nitrogen metabolism changed in the soybean plant. These results suggest the significance of a time-series analysis for understanding the relationship between the microbial community and host plant physiology.

RevDate: 2019-08-15

Pérez-Jaramillo JE, de Hollander M, Ramírez CA, et al (2019)

Deciphering rhizosphere microbiome assembly of wild and modern common bean (Phaseolus vulgaris) in native and agricultural soils from Colombia.

Microbiome, 7(1):114 pii:10.1186/s40168-019-0727-1.

BACKGROUND: Modern crop varieties are typically cultivated in agriculturally well-managed soils far from the centers of origin of their wild relatives. How this habitat expansion impacted plant microbiome assembly is not well understood.

RESULTS: Here, we investigated if the transition from a native to an agricultural soil affected rhizobacterial community assembly of wild and modern common bean (Phaseolus vulgaris) and if this led to a depletion of rhizobacterial diversity. The impact of the bean genotype on rhizobacterial assembly was more prominent in the agricultural soil than in the native soil. Although only 113 operational taxonomic units (OTUs) out of a total of 15,925 were shared by all eight bean accessions grown in native and agricultural soils, this core microbiome represented a large fraction (25.9%) of all sequence reads. More OTUs were exclusively found in the rhizosphere of common bean in the agricultural soil as compared to the native soil and in the rhizosphere of modern bean accessions as compared to wild accessions. Co-occurrence analyses further showed a reduction in complexity of the interactions in the bean rhizosphere microbiome in the agricultural soil as compared to the native soil.

CONCLUSIONS: Collectively, these results suggest that habitat expansion of common bean from its native soil environment to an agricultural context had an unexpected overall positive effect on rhizobacterial diversity and led to a stronger bean genotype-dependent effect on rhizosphere microbiome assembly.

RevDate: 2019-08-15

Drengenes C, Wiker HG, Kalananthan T, et al (2019)

Laboratory contamination in airway microbiome studies.

BMC microbiology, 19(1):187 pii:10.1186/s12866-019-1560-1.

BACKGROUND: The low bacterial load in samples acquired from the lungs, have made studies on the airway microbiome vulnerable to contamination from bacterial DNA introduced during sampling and laboratory processing. We have examined the impact of laboratory contamination on samples collected from the lower airways by protected (through a sterile catheter) bronchoscopy and explored various in silico approaches to dealing with the contamination post-sequencing. Our analyses included quantitative PCR and targeted amplicon sequencing of the bacterial 16S rRNA gene.

RESULTS: The mean bacterial load varied by sample type for the 23 study subjects (oral wash>1st fraction of protected bronchoalveolar lavage>protected specimen brush>2nd fraction of protected bronchoalveolar lavage; p < 0.001). By comparison to a dilution series of know bacterial composition and load, an estimated 10-50% of the bacterial community profiles for lower airway samples could be traced back to contaminating bacterial DNA introduced from the laboratory. We determined the main source of laboratory contaminants to be the DNA extraction kit (FastDNA Spin Kit). The removal of contaminants identified using tools within the Decontam R package appeared to provide a balance between keeping and removing taxa found in both negative controls and study samples.

CONCLUSIONS: The influence of laboratory contamination will vary across airway microbiome studies. By reporting estimates of contaminant levels and taking use of contaminant identification tools (e.g. the Decontam R package) based on statistical models that limit the subjectivity of the researcher, the accuracy of inter-study comparisons can be improved.

RevDate: 2019-08-15

Khan I, Ullah N, Zha L, et al (2019)

Alteration of Gut Microbiota in Inflammatory Bowel Disease (IBD): Cause or Consequence? IBD Treatment Targeting the Gut Microbiome.

Pathogens (Basel, Switzerland), 8(3): pii:pathogens8030126.

Inflammatory bowel disease (IBD) is a chronic complex inflammatory gut pathological condition, examples of which include Crohn's disease (CD) and ulcerative colitis (UC), which is associated with significant morbidity. Although the etiology of IBD is unknown, gut microbiota alteration (dysbiosis) is considered a novel factor involved in the pathogenesis of IBD. The gut microbiota acts as a metabolic organ and contributes to human health by performing various physiological functions; deviation in the gut flora composition is involved in various disease pathologies, including IBD. This review aims to summarize the current knowledge of gut microbiota alteration in IBD and how this contributes to intestinal inflammation, as well as explore the potential role of gut microbiota-based treatment approaches for the prevention and treatment of IBD. The current literature has clearly demonstrated a perturbation of the gut microbiota in IBD patients and mice colitis models, but a clear causal link of cause and effect has not yet been presented. In addition, gut microbiota-based therapeutic approaches have also shown good evidence of their effects in the amelioration of colitis in animal models (mice) and IBD patients, which indicates that gut flora might be a new promising therapeutic target for the treatment of IBD. However, insufficient data and confusing results from previous studies have led to a failure to define a core microbiome associated with IBD and the hidden mechanism of pathogenesis, which suggests that well-designed randomized control trials and mouse models are required for further research. In addition, a better understanding of this ecosystem will also determine the role of prebiotics and probiotics as therapeutic agents in the management of IBD.

RevDate: 2019-08-14

Mahomoodally MF, Aumeeruddy MZ, Rengasamy KRR, et al (2019)

Ginger and its Active Compounds in Cancer Therapy: From Folk uses to Nano-therapeutic Applications.

Seminars in cancer biology pii:S1044-579X(19)30213-5 [Epub ahead of print].

Ginger is a spice that is renowned for its characteristic aromatic fragrance and pungent taste, with documented healing properties. Field studies conducted in several Asian and African countries revealed that ginger is used traditionally in the management of cancer. The scientific community has probed into the biological validation of its extracts and isolated compounds including the gingerols, shogaols, zingiberene, and zingerone, through in-vitro and in-vivo studies. Nonetheless, an updated compilation of these data together with a deep mechanistic approach is yet to be provided. Accordingly, this review highlights the mechanisms and therapeutics of ginger and its bioactive compounds focused on a cancer context and these evidence are based on the (i) cytotoxic effect against cancer cell lines, (ii) enzyme inhibitory action, (iii) combination therapy with chemotherapeutic and phenolic compounds, (iv) possible links to the microbiome and (v) the use of nano-formulations of ginger bioactive compounds as a more effective drug delivery strategy in cancer therapy.

RevDate: 2019-08-14

Huggins MA, Sjaastad FV, Pierson M, et al (2019)

Microbial Exposure Enhances Immunity to Pathogens Recognized by TLR2 but Increases Susceptibility to Cytokine Storm through TLR4 Sensitization.

Cell reports, 28(7):1729-1743.e5.

Microbial exposures can define an individual's basal immune state. Cohousing specific pathogen-free (SPF) mice with pet store mice, which harbor numerous infectious microbes, results in global changes to the immune system, including increased circulating phagocytes and elevated inflammatory cytokines. How these differences in the basal immune state influence the acute response to systemic infection is unclear. Cohoused mice exhibit enhanced protection from virulent Listeria monocytogenes (LM) infection, but increased morbidity and mortality to polymicrobial sepsis. Cohoused mice have more TLR2+ and TLR4+ phagocytes, enhancing recognition of microbes through pattern-recognition receptors. However, the response to a TLR2 ligand is muted in cohoused mice, whereas the response to a TLR4 ligand is greatly amplified, suggesting a basis for the distinct response to Listeria monocytogenes and sepsis. Our data illustrate how microbial exposure can enhance the immune response to unrelated challenges but also increase the risk of immunopathology from a severe cytokine storm.

RevDate: 2019-08-14

Arizza V, Vecchioni L, Caracappa S, et al (2019)

New insights into the gut microbiome in loggerhead sea turtles Caretta caretta stranded on the Mediterranean coast.

PloS one, 14(8):e0220329 pii:PONE-D-19-06261.

Caretta caretta is the most common sea turtle species in the Mediterranean Sea. The species is threatened by anthropomorphic activity that causes thousands of deaths and hundreds of strandings along the Mediterranean coast. Stranded turtles are often cared for in rehabilitation centres until they recover or die. The objective of this study was to characterize the gut microbiome of nine sea turtles stranded along the Sicilian coast of the Mediterranean Sea using high-throughput sequencing analysis targeting V3-V4 regions of the bacterial 16S rRNA gene. Stool samples were collected from eight specimens hosted in the recovery centre after a few days of hospitalization (under 7) and from one hosted for many weeks (78 days). To better explore the role of bacterial communities in loggerhead sea turtles, we compared our data with published fecal microbiomes from specimens stranded along the Tuscan and Ligurian coast. Our results highlight that, despite the different origin, size and health conditions of the animals, Firmicutes, Bacteroidetes and Proteobacteria constitute the main components of the microbiota. This study widens our knowledge on the gut microbiome of sea turtles and could be helpful for the set up of rehabilitation therapies of stranded animals after recovery in specialized centres.

RevDate: 2019-08-14

Hyde J, Gorham C, Brackney DE, et al (2019)

Antibiotic resistant bacteria and commensal fungi are common and conserved in the mosquito microbiome.

PloS one, 14(8):e0218907 pii:PONE-D-19-16438.

The emerging and increasing prevalence of bacterial antibiotic resistance is a significant public health challenge. To begin to tackle this problem, it will be critical to not only understand the origins of this resistance but also document environmental reservoirs of antibiotic resistance. In this study we investigated the possibility that both colony and field caught mosquitoes could harbor antibiotic resistant bacteria. Specifically, we characterized the antibiotic resistant bacterial populations from colony-reared Aedes aegypti larvae and adults and two field caught mosquito species Coquillettidia perturbans and Ochlerotatus canadensis. The cultured bacterial populations were dominated by isolates belonging to the class Gammaproteobacteria. Among the antibiotic resistant populations, we found bacteria resistant to carbenicillin, kanamycin, and tetracycline, including bacteria resistant to a cocktail of all three antibiotics in combination. The antibiotic resistant bacteria were numerically rare, at most 5% of total cell counts. Isolates were characterized by 16S rRNA gene sequencing, and clustering into Operational Taxonomic Units (OTUs; 99% sequence identity). 27 antibiotic resistant OTUs were identified, although members of an OTU did not always share the same resistance profile. This suggests the clustering was either not sensitive enough to distinguish different bacteria taxa or different antibiotic resistant sub-populations exist within an OTU. Finally, the antibiotic selection opened up a niche to culture mosquito-associated fungi, and 10 fungal OTUs (28S rRNA gene sequencing) were identified. Two fungal OTUs both classified to the class Microbotryomycetes were commonly identified in the field-caught mosquitoes. Thus, in this study we demonstrate that antibiotic resistant bacteria and certain fungi are common and conserved mosquito microbiome members. These observations highlight the potential of invertebrates to serve as vehicles for the spread of antibiotic resistance throughout the environment.

RevDate: 2019-08-14

Peng M, Tabashsum Z, Patel P, et al (2019)

Prevention of enteric bacterial infections and modulation of gut microbiota with conjugated linoleic acids producing Lactobacillus in mice.

Gut microbes [Epub ahead of print].

Probiotics are recognized for outcompeting pathogenic bacteria by competitive receptor-mediated colonization and secretion of functional metabolites which are antimicrobial against certain microbes as well as improving host's gut health and immunity. Recently, we have constructed a bioactive Lactobacillus casei (LC) strain, LC+mcra, by inserting mcra (myosin cross-reactive antigen) gene, which stimulates the conversion of conjugated linoleic acids. In this study, we evaluated the modulation of gut microbiome and protective roles of LC+mcra against pathogenic Salmonella enterica serovar Typhimurium (ST) and enterohemorrhagic E. coli (EHEC) infections in BALB/cJ mice. We observed that LC+mcra colonized efficiently in mice gut intestine and competitively reduced the infection with ST and EHEC in various locations of small and large intestine, specifically cecum, jejunum, and ileum (p < 0.05). Positive modulation of the cecal microbiota, for example, higher relative abundances of Firmicutes, lower relative abundances of Proteobacteria, and increased bacterial species diversity/richness, was detected in ST-challenged mice pretreated with LC+mcra based on 16S metagenomic sequencing. Cytokine gene expression analysis indicated that mice pretreated with LC+mcra associated with attenuated bacterial pathogen-induced gut inflammation. Furthermore, mice fed daily with LC+mcra for one week could protect themselves from the impairments caused by enteric infections with ST or EHEC. These impairments include weight loss, negative hematological changes, intestinal histological alterations, and potential death. This in vivo study suggests that daily consumption of novel conjugated linoleic acids over-producing probiotic effectively improves intestinal microbiota composition and prevents/combats foodborne enteric bacterial infections with pathogenic Salmonella and diarrheagenic E. coli.

RevDate: 2019-08-14

Zhu YX, Song ZR, Song YL, et al (2019)

The microbiota in spider mite faeces potentially reflects intestinal bacterial communities in the host.

Insect science [Epub ahead of print].

Microorganisms provide many physiological functions to herbivorous hosts. Spider mites (genus Tetranychus) are important agricultural pests throughout the world, however, the composition of spider mite microbial community, especially gut microbiome, remains unclear. Here, we investigated the bacterial community in five spider mite species and their associated faeces by deep sequencing of the 16S rRNA gene. The composition of the bacterial community was significantly different among the five prevalent spider mite species, and some bacterial symbionts showed host-species specificity. Moreover, the abundance of the bacterial community in spider mite faeces was significantly higher than that in the corresponding spider mite samples. However, Flavobacterium was detected in all samples, and represent a "core microbiome". Remarkably, the maternally inherited endosymbiont Wolbachia was detected in both spider mite and faeces. Overall, these results offer insight into the complex community of symbionts in spider mites, and give a new direction for future studies. This article is protected by copyright. All rights reserved.

RevDate: 2019-08-14

Reza MM, Finlay BB, S Pettersson (2019)

Gut microbes, ageing & organ function: a chameleon in modern biology?.

EMBO molecular medicine [Epub ahead of print].

All species, including humans, are cohabited by a myriad of microbial species, which massively influences body function in a diet-, exercise- and age-dependent manner. The microbiome composition differs between individuals, partly due to the polymorphic immune system, as well as the environment, making the microbe-host interplay unique in each one of us. Ageing is a gradual loss of function in part due to reduced repair mechanisms and accumulation of tissue damage through mechanisms largely unknown. Accumulating evidence suggests that our indigenous microbes, a known major regulator of human physiology, are also connected to regulate the ageing process through signalling pathways and metabolites though the biological mechanisms are unknown. At an ageing meeting in Singapore in 2018, investigators discussed the current understanding of microbe regulation and its impact on healthy ageing. This review summarizes the highlights from the meeting and conveys some of the new ideas that emerged around gut microbes and the biology of ageing. While highly speculative, an idea emerged in which gut microbes constantly respond and evolve to environmental cues, as part of an ageing process, thus serving as a second messenger to support and attenuate organ decline in a diet-, gender- and age-dependent manner.

RevDate: 2019-08-14

Zhang F, Wang M, Yang J, et al (2019)

Response of gut microbiota in type 2 diabetes to hypoglycemic agents.

Endocrine pii:10.1007/s12020-019-02041-5 [Epub ahead of print].

PURPOSE: Accumulated evidence has indicated that the gut microbiome affected the pharmacology of anti-diabetic agents, and their metabolic products induced by the agents transformed the structure of gastrointestinal microbiota in return. However, the studies around heredity, ethnicity, or living condition, referring to human microbiome were mostly represented by an occidental pattern partial and rare studies that focused on the effect of several first-line hypoglycemic agents on the gut flora in a single medical center. Therefore, we aimed to explore the interaction between gut microbiome and type 2 diabetes (T2D) or hypoglycemics in Chinese population.

METHODS: A total of 130 T2D patients with a specific hypoglycemic treatment and 50 healthy volunteers were enrolled in this study. Gut microbiome compositons were analyzed by 16S ribosomal RNA gene-based sequencing protocol.

RESULTS: Hypoglycemic agents contributed to the alteration of specific species in gut bacteria rather than its total diversity. Metformin increased the abundance of Spirochaete, Turicibacter, and Fusobacterium. Insulin also increased Fusobacterium, and α-glucosidase inhibitors (α-GIs) contributed to the plentitude of Bifidobacterium and Lactobacillus. Both metformin and insulin improved taurine and hypotaurine metabolism, and α-GI promoted several amino acid pathways. Although the community of gut microbiota with metformin and insulin showed similarity, significant differences were available in each diabetic group with hypoglycemia.

CONCLUSIONS: Gut microbiota is significantly associated with anti-diabetic agents. The gut microbiome and metabolism have shown respective characteristics in different T2D groups, which were also significantly different from the healthy group. This study provides some new insights for identification and exploration of the pathogenesis of T2D.

RevDate: 2019-08-14

Ribaldone DG, Pellicano R, GC Actis (2019)

Inflammation in gastrointestinal disorders: prevalent socioeconomic factors.

Clinical and experimental gastroenterology, 12:321-329 pii:210844.

Western populations harbor a chronic inflammation pattern that lacks organ cardinal signs (edema, increased temperature, pain, and impaired function), releases increased levels of C-reactive protein, and often runs a creeping clinical course with generalized debilitating disease superimposed on system-specific involvement, mostly including nervous tissue (multiple sclerosis, Parkinson's syndromes), joints (arthritis), and skin (psoriasis). A finalistic interpretation may apply to the consideration of the gut as the source of inflammation. In fact, these kind of local events as well as the remote manifestations named above, could be conditioned by the microbiome, the huge cell population indwelling the gut which is under growing scrutiny. The role of the gut as a barrier organ justifies lingering submucosal inflammation as a patrolling activity to maintain bodily integrity; the microbiome, launching inflammogenic signals in response to abrupt diet changes, confers to gut inflammation a socioeconomic vector calling for hitherto unrecognized multi-disciplinary interventions.

RevDate: 2019-08-14

Swe PM, Zakrzewski M, Waddell R, et al (2019)

High-throughput metagenome analysis of the Sarcoptes scabiei internal microbiota and in-situ identification of intestinal Streptomyces sp.

Scientific reports, 9(1):11744 pii:10.1038/s41598-019-47892-0.

Multiple parasitic arthropods of medical importance depend on symbiotic bacteria. While the link between scabies and secondary bacterial infections causing post infective complications of Group A streptococcal and staphylococcal pyoderma is increasingly recognized, very little is known about the microbiota of Sarcoptes scabiei. Here we analyze adult female mite and egg metagenome datasets. The majority of adult mite bacterial reads matched with Enterobacteriaceae (phylum Proteobacteria), followed by Corynebacteriaceae (phylum Actinobacteria). Klebsiella was the most dominant genus (78%) and Corynebacterium constituted 9% of the assigned sequences. Scabies mite eggs had a more diverse microbial composition with sequences from Proteobacteria being the most dominant (75%), while Actinobacteria, Bacteroidetes and Firmicutes accounted for 23% of the egg microbiome sequences. DNA sequences of a potential endosymbiont, namely Streptomyces, were identified in the metagenome sequence data of both life stages. The presence of Streptomyces was confirmed by conventional PCR. Digital droplet PCR indicated higher Streptomyces numbers in adult mites compared to eggs. Streptomyces were localized histologically in the scabies mite gut and faecal pellets by Fluorescent In Situ Hybridization (FISH). Streptomyces may have essential symbiotic roles in the scabies parasite intestinal system requiring further investigation.

RevDate: 2019-08-14

Pereira EM, de Mattos CS, Dos Santos OC, et al (2019)

Staphylococcus hominis subspecies can be identified by SDS-PAGE or MALDI-TOF MS profiles.

Scientific reports, 9(1):11736 pii:10.1038/s41598-019-48248-4.

Staphylococcus hominis is part of the normal human microbiome. Two subspecies, S. hominis hominis (Shh) and S. hominis novobiosepticus (Shn), have clinical significance. Forty-nine S. hominis isolates were analyzed by the MicroScan automated system, SDS-PAGE and MALDI-TOF methods, followed by partial sequencing of the 16S rDNA gene. The trehalose fermentation test, disk diffusion and broth microdilution tests were used to identify (novobiocin test) and access the susceptibility to oxacillin and vancomycin of isolates. The SCCmec elements and genomic diversity were evaluated by PCR and PFGE methods, respectively. Profiles of 28 (57%; 8 Shh and 20 Shn) isolates corroborated with the results found in all the applied methods of identification. The remaining 21 (43%) isolates were phenotypically identified as Shh by MicroScan; however, they were identified as Shn by SDS-PAGE and mass spectral, and confirmed by 16S rDNA sequencing. Among 41 isolates identified as Shn by the molecular and mass spectrometry methods, 19 (41%) were novobiocin-sensitive, and the trehalose test indicated 11 positive isolates, which are considered atypical phenotypic results for this subspecies. In addition, 92.7% of the isolates identified as Shn by these methods carried mecA gene, while only 12.5% of the Shh isolates were positive. Together, the results highlighted the SDS-PAGE and MALDI-TOF MS methods as promising tools for discriminating S. hominis subspecies.

RevDate: 2019-08-14

Luck H, Khan S, Kim JH, et al (2019)

Gut-associated IgA+ immune cells regulate obesity-related insulin resistance.

Nature communications, 10(1):3650 pii:10.1038/s41467-019-11370-y.

The intestinal immune system is emerging as an important contributor to obesity-related insulin resistance, but the role of intestinal B cells in this context is unclear. Here, we show that high fat diet (HFD) feeding alters intestinal IgA+ immune cells and that IgA is a critical immune regulator of glucose homeostasis. Obese mice have fewer IgA+ immune cells and less secretory IgA and IgA-promoting immune mediators. HFD-fed IgA-deficient mice have dysfunctional glucose metabolism, a phenotype that can be recapitulated by adoptive transfer of intestinal-associated pan-B cells. Mechanistically, IgA is a crucial link that controls intestinal and adipose tissue inflammation, intestinal permeability, microbial encroachment and the composition of the intestinal microbiome during HFD. Current glucose-lowering therapies, including metformin, affect intestinal-related IgA+ B cell populations in mice, while bariatric surgery regimen alters the level of fecal secretory IgA in humans. These findings identify intestinal IgA+ immune cells as mucosal mediators of whole-body glucose regulation in diet-induced metabolic disease.

RevDate: 2019-08-14

Jang HR, Park HJ, Kang D, et al (2019)

A protective mechanism of probiotic Lactobacillus against hepatic steatosis via reducing host intestinal fatty acid absorption.

Experimental & molecular medicine, 51(8):95 pii:10.1038/s12276-019-0293-4.

The gut microbiome has been known to contribute up to ~30% of the energy absorption of the host. Although various beneficial mechanisms of probiotics have been suggested for non-alcoholic fatty liver disease (NAFLD), whether and which probiotics impact the host's intestinal energy absorption have not yet been quantitatively studied. Here, we suggest a novel mechanism of probiotics against NAFLD, in which Lactobacillus rhamnosus GG, the most common probiotic, shares intestinal fatty acids and prevents the development of diet-induced hepatic steatosis. By using quantitative methods (radioactive tracers and LC-MS) under both in vitro and in vivo conditions, we found that bacteria and hosts competed for fatty acid absorption in the intestine, resulting in decreased weight gain, body fat mass, and hepatic lipid accumulation without differences in calorie intake and excretion in mice fed the probiotic bacteria.

RevDate: 2019-08-14

Edwards VL, Smith SB, McComb EJ, et al (2019)

The Cervicovaginal Microbiota-Host Interaction Modulates Chlamydia trachomatis Infection.

mBio, 10(4): pii:mBio.01548-19.

The mechanism(s) by which Lactobacillus-dominated cervicovaginal microbiota provide a barrier to Chlamydia trachomatis infection remain(s) unknown. Here we evaluate the impact of different Lactobacillus spp. identified via culture-independent metataxonomic analysis of C. trachomatis-infected women on C. trachomatis infection in a three-dimensional (3D) cervical epithelium model. Lactobacillus spp. that specifically produce d(-) lactic acid were associated with long-term protection against C. trachomatis infection, consistent with reduced protection associated with Lactobacillus iners, which does not produce this isoform, and with decreased epithelial cell proliferation, consistent with the observed prolonged protective effect. Transcriptomic analysis revealed that epigenetic modifications involving histone deacetylase-controlled pathways are integral to the cross talk between host and microbiota. These results highlight a fundamental mechanism whereby the cervicovaginal microbiota modulates host functions to protect against C. trachomatis infection.IMPORTANCE The vaginal microbiota is believed to protect women against Chlamydia trachomatis, the etiologic agent of the most prevalent sexually transmitted infection (STI) in developed countries. The mechanism underlying this protection has remained elusive. Here, we reveal the comprehensive strategy by which the cervicovaginal microbiota modulates host functions to protect against chlamydial infection, thereby providing a novel conceptual mechanistic understanding. Major implications of this work are that (i) the impact of the vaginal microbiota on the epithelium should be considered in future studies of chlamydial infection and other STIs and (ii) a fundamental understanding of the cervicovaginal microbiota's role in protection against STIs may enable the development of novel microbiome-based therapeutic strategies to protect women from infection and improve vaginal and cervical health.

RevDate: 2019-08-14

Small CM, Currey M, Beck EA, et al (2019)

Highly Reproducible 16S Sequencing Facilitates Measurement of Host Genetic Influences on the Stickleback Gut Microbiome.

mSystems, 4(4): pii:4/4/e00331-19.

Multicellular organisms interact with resident microbes in important ways, and a better understanding of host-microbe interactions is aided by tools such as high-throughput 16S sequencing. However, rigorous evaluation of the veracity of these tools in a different context from which they were developed has often lagged behind. Our goal was to perform one such critical test by examining how variation in tissue preparation and DNA isolation could affect inferences about gut microbiome variation between two genetically divergent lines of threespine stickleback fish maintained in the same laboratory environment. Using careful experimental design and intensive sampling of individuals, we addressed technical and biological sources of variation in 16S-based estimates of microbial diversity. After employing a two-tiered bead beating approach that comprised tissue homogenization followed by microbial lysis in subsamples, we found an extremely minor effect of DNA isolation protocol relative to among-host microbial diversity differences. Abundance estimates for rare operational taxonomic units (OTUs), however, showed much lower reproducibility. Gut microbiome composition was highly variable across fish-even among cohoused siblings-relative to technical replicates, but a subtle effect of host genotype (stickleback line) was nevertheless detected for some microbial taxa.IMPORTANCE Our findings demonstrate the importance of appropriately quantifying biological and technical variance components when attempting to understand major influences on high-throughput microbiome data. Our focus was on understanding among-host (biological) variance in community metrics and its magnitude in relation to within-host (technical) variance, because meaningful comparisons among individuals are necessary in addressing major questions in host-microbe ecology and evolution, such as heritability of the microbiome. Our study design and insights should provide a useful example for others desiring to quantify microbiome variation at biological levels in the face of various technical factors in a variety of systems.

RevDate: 2019-08-14

Zhang S, Song W, Wemheuer B, et al (2019)

Comparative Genomics Reveals Ecological and Evolutionary Insights into Sponge-Associated Thaumarchaeota.

mSystems, 4(4): pii:4/4/e00288-19.

Thaumarchaeota are frequently reported to associate with marine sponges (phylum Porifera); however, little is known about the features that distinguish them from their free-living thaumarchaeal counterparts. In this study, thaumarchaeal metagenome-assembled genomes (MAGs) were reconstructed from metagenomic data sets derived from the marine sponges Hexadella detritifera, Hexadella cf. detritifera, and Stylissa flabelliformis Phylogenetic and taxonomic analyses revealed that the three thaumarchaeal MAGs represent two new species within the genus Nitrosopumilus and one novel genus, for which we propose the names "CandidatusUNitrosopumilus hexadellus," "CandidatusUNitrosopumilus detritiferus," and "CandidatusUCenporiarchaeum stylissum" (the U superscript indicates that the taxon is uncultured). Comparison of these genomes to data from the Sponge Earth Microbiome Project revealed that "CaUCenporiarchaeum stylissum" has been exclusively detected in sponges and can hence be classified as a specialist, while "CaUNitrosopumilus detritiferus" and "CaUNitrosopumilus hexadellus" are also detected outside the sponge holobiont and likely lead a generalist lifestyle. Comparison of the sponge-associated MAGs to genomes of free-living Thaumarchaeota revealed signatures that indicate functional features of a sponge-associated lifestyle, and these features were related to nutrient transport and metabolism, restriction-modification, defense mechanisms, and host interactions. Each species exhibited distinct functional traits, suggesting that they have reached different stages of evolutionary adaptation and/or occupy distinct ecological niches within their sponge hosts. Our study therefore offers new evolutionary and ecological insights into the symbiosis between sponges and their thaumarchaeal symbionts.IMPORTANCE Sponges represent ecologically important models to understand the evolution of symbiotic interactions of metazoans with microbial symbionts. Thaumarchaeota are commonly found in sponges, but their potential adaptations to a host-associated lifestyle are largely unknown. Here, we present three novel sponge-associated thaumarchaeal species and compare their genomic and predicted functional features with those of closely related free-living counterparts. We found different degrees of specialization of these thaumarchaeal species to the sponge environment that is reflected in their host distribution and their predicted molecular and metabolic properties. Our results indicate that Thaumarchaeota may have reached different stages of evolutionary adaptation in their symbiosis with sponges.

RevDate: 2019-08-14

Becker CG, Bletz MC, Greenspan SE, et al (2019)

Low-load pathogen spillover predicts shifts in skin microbiome and survival of a terrestrial-breeding amphibian.

Proceedings. Biological sciences, 286(1908):20191114.

Wildlife disease dynamics are strongly influenced by the structure of host communities and their symbiotic microbiota. Conspicuous amphibian declines associated with the waterborne fungal pathogen Batrachochytrium dendrobatidis (Bd) have been observed in aquatic-breeding frogs globally. However, less attention has been given to cryptic terrestrial-breeding amphibians that have also been declining in tropical regions. By experimentally manipulating multiple tropical amphibian assemblages harbouring natural microbial communities, we tested whether Bd spillover from naturally infected aquatic-breeding frogs could lead to Bd amplification and mortality in our focal terrestrial-breeding host: the pumpkin toadlet Brachycephalus pitanga. We also tested whether the strength of spillover could vary depending on skin bacterial transmission within host assemblages. Terrestrial-breeding toadlets acquired lethal spillover infections from neighbouring aquatic hosts and experienced dramatic but generally non-protective shifts in skin bacterial composition primarily attributable to their Bd infections. By contrast, aquatic-breeding amphibians maintained mild Bd infections and higher survival, with shifts in bacterial microbiomes that were unrelated to Bd infections. Our results indicate that Bd spillover from even mildly infected aquatic-breeding hosts may lead to dysbiosis and mortality in terrestrial-breeding species, underscoring the need to further investigate recent population declines of terrestrial-breeding amphibians in the tropics.

RevDate: 2019-08-14

Drago L, Panelli S, Bandi C, et al (2019)

What Pediatricians Should Know Before Studying Gut Microbiota.

Journal of clinical medicine, 8(8): pii:jcm8081206.

Billions of microorganisms, or "microbiota", inhabit the gut and affect its homeostasis, influencing, and sometimes causing if altered, a multitude of diseases. The genomes of the microbes that form the gut ecosystem should be summed to the human genome to form the hologenome due to their influence on human physiology; hence the term "microbiome" is commonly used to refer to the genetic make-up and gene-gene interactions of microbes. This review attempts to provide insight into this recently discovered vital organ of the human body, which has yet to be fully explored. We herein discuss the rhythm and shaping of the microbiome at birth and during the first years leading up to adolescence. Furthermore, important issues to consider for conducting a reliable microbiome study including study design, inclusion/exclusion criteria, sample collection, storage, and variability of different sampling methods as well as the basic terminology of molecular approaches, data analysis, and clinical interpretation of results are addressed. This basic knowledge aims to provide the pediatricians with a key tool to avoid data dispersion and pitfalls during child microbiota study.

RevDate: 2019-08-14

Hayashi T, Fujita K, Matsushita M, et al (2019)

Main Inflammatory Cells and Potentials of Anti-Inflammatory Agents in Prostate Cancer.

Cancers, 11(8): pii:cancers11081153.

Prostate cancer is the most common type of cancer and the leading cause of cancer deaths among men in many countries. Preventing progression is a major concern for prostate cancer patients on active surveillance, patients with recurrence after radical therapies, and patients who acquired resistance to systemic therapies. Inflammation, which is induced by various factors such as infection, microbiome, obesity, and a high-fat diet, is the major etiology in the development of prostate cancer. Inflammatory cells play important roles in tumor progression. Various immune cells including tumor-associated neutrophils, tumor-infiltrating macrophages, myeloid-derived suppressor cells, and mast cells promote prostate cancer via various intercellular signaling. Further basic studies examining the relationship between the inflammatory process and prostate cancer progression are warranted. Interventions by medications and diets to control systemic and/or local inflammation might be effective therapies for prostate cancer progression. Epidemiological investigations and basic research using human immune cells or mouse models have revealed that non-steroidal anti-inflammatory drugs, metformin, statins, soy isoflavones, and other diets are potential interventions for preventing progression of prostate cancer by suppressing inflammation. It is essential to evaluate appropriate indications and doses of each drug and diet.

RevDate: 2019-08-13

Sood A, Singh A, Mahajan R, et al (2019)

Acceptability, Tolerability and Safety of Faecal Microbiota Transplantation in patients with active Ulcerative Colitis (AT&S Study).

Journal of gastroenterology and hepatology [Epub ahead of print].

BACKGROUND: Faecal microbiota transplantation (FMT) targets gut microbiome dysbiosis and is an emerging therapy for ulcerative colitis (UC). Though initial results with FMT in patients with active UC are encouraging, data regarding its acceptability, tolerability and safety are scant.

METHODS: A retrospective analysis of patients with active UC (Mayo clinic score ≥4), who received multisession FMT (at weeks 0, 2, 6, 10, 14, 18 and 22) via colonoscopy between June 2016 and June 2018, was done. Patient acceptability, tolerability and immediate and long term safety of the therapy were assessed.

RESULTS: Of the 129 patients with active UC who were offered FMT, 101 patients consented; giving acceptability of 78.3%. Faecal slurry retention time, improved with each session (3.27 ± 1.06 hours for first session vs 5.12 ± 0.5 hours for seventh session). Abdominal discomfort, flatulence, abdominal distension, borborygmi and low grade fever (30.8%, 15.9%, 9.8%, 7.9% and 7.6% respectively) were the most common post procedural short term adverse events. Long term adverse events included new-onset urticaria (n=2,4.3%), arthritis/arthralgias(n=3, 6.5%), depression (n=1, 2.2%), partial sensorineural hearing loss (n=1, 2.2%), and allergic bronchitis (n=1, 2.2%). Thirteen (12.9%) patients dropped out due to adverse events.

CONCLUSION: FMT appears to be a safe and well tolerated procedure, with good acceptability in patients with active UC.

RevDate: 2019-08-13

Ari O, Karabudak S, Kalcioglu MT, et al (2019)

The bacteriome of otitis media with effusion: Does it originate from the adenoid?.

International journal of pediatric otorhinolaryngology, 126:109624 pii:S0165-5876(19)30368-4 [Epub ahead of print].

OBJECTIVE: The aim of this study was to evaluate the composition and the diversity of bacteriome in middle ear effusion (MEE) and adenoid specimens of pediatric patients having otitis media with effusion (OME).

MATERIALS AND METHODS: Sample collection from children with OME followed by next generation sequencing. Seventeen adenoid and 43 middle ear effusion specimens from 25 children having OME were evaluated. Microbiome analysis was performed via Ion 16S rRNA metagenomics kit.

RESULTS: Twenty-two different bacterial species were identified from all of the samples analyzed. There were variations in the prevalence and relative abundance of the bacteriome observed between adenoid and MEE samples. MEE microbiome was significantly dominated by Alloicoccus otitis (44%), Turicella otitidis (6%), and Staphylococcus auricularis (3%). Whereas, Rothia mucilaginosa (39%), R. dentocariosa (11%), S. aureus (5%), Veillonella rogosae (2%), Granulicatella elegans (2%), Granulicatella adiacens (2%), Eikenella corrodens (1%), and Prevotella nanceiensis (1%) had significantly higher relative abundance in adenoid samples. Overall, there was no statistically significant difference in alpha diversity of MEE and adenoid samples, whereas adenoid samples constituted a cluster in the beta diversity graph.

CONCLUSION: Bacteriome of MEE is mostly dominated by A. otitis yet accompanied by other bacteria with lower relative abundances suggests that OME is likely to be a polymicrobial process. Despite similarities, significant differences in relative abundances of several predominant species between bacteriome in the MEE and adenoid put the theory that OME in children is originated from the adenoids under question.

RevDate: 2019-08-13

Thumann TA, Pferschy-Wenzig EM, Moissl-Eichinger C, et al (2019)

The role of gut microbiota for the activity of medicinal plants traditionally used in the European Union for gastrointestinal disorders.

Journal of ethnopharmacology pii:S0378-8741(19)31277-2 [Epub ahead of print].

. Many medicinal plants have been traditionally used for the treatment of gastrointestinal disorders. According to the monographs published by the Committee on Herbal Medicinal Products (HMPC) at the European Medicines Agency, currently 44 medicinal plants are recommended in the European Union for the treatment of gastrointestinal disorders based on traditional use. The main indications are functional and chronic gastrointestinal disorders, such as functional dyspepsia and irritable bowel syndrome (IBS), and typical effects of these plants are stimulation of gastric secretion, spasmolytic and carminative effects, soothing effects on the gastrointestinal mucosa, laxative effects, adstringent or antidiarrheal activities, and anti-inflammatory effects. A possible interaction with human gut microbiota has hardly been considered so far, although it is quite likely.

AIM OF THE STUDY: . In this review, we aimed to identify and evaluate published studies which have investigated interactions of these plants with the gut microbiome.

RESULTS: . According to this survey, only a minor portion of the 44 medicinal plants considered in EMA monographs for the treatment of gastrointestinal diseases has been studied so far with regard to potential interactions with gut microbiota. We could identify eight relevant in vitro studies that have been performed with six of these medicinal plants, 17 in vivo studies performed in experimental animals involving seven of the medicinal plants, and three trials in humans performed with two of the plants. The most robust evidence exists for the use of inulin as a prebiotic, and in this context also the prebiotic activity of chicory root has been investigated quite intensively. Flaxseed dietary fibers are also known to be fermented by gut microbiota to short chain fatty acids, leading to prebiotic effects. This could cause a health-beneficial modulation of gut microbiota by flaxseed supplementation. In flaxseed, also other compound classes like lignans and polyunsaturated fatty acids are present, that also have been shown to interact with gut microbiota. Drugs rich in tannins and anthocyanins also interact intensively with gut microbiota, since these compounds reach the colon at high levels in unchanged forms. Tannins and anthocyanins are intensively metabolized by certain gut bacteria, leading to the generation of small, bioavailable and potentially bioactive metabolites. Moreover, interaction with these compounds may exert a prebiotic-like effect on gut microbiota. Gut microbial metabolization has also been shown for certain licorice constituents, but their potential effects on gut microbiota still need to be investigated in detail. Only a limited amount of studies investigated the interactions of essential oil- and secoiridoid-containing drugs with human gut microbiota. However, other constituents present in some of these drugs, like curcumin (curcuma), shogaol (ginger), and rosmarinic acid have been shown to be metabolized by human gut microbiota, and preliminary data also indicate potential gut microbiome modulatory effects. To conclude, the interaction with gut microbiota is still not fully investigated for many herbal drugs traditionally used for gastrointestinal disorders, which offers a vast field for future research.

RevDate: 2019-08-13

Husson J, Mongodin EF, JS Bromberg (2019)

Invited Editorial re: Vendor-Specific Microbiome Controls both Acute and Chronic Murine Lung Allograft Rejection by Altering CD4+Foxp3+ Regulatory T Cell Levels.

Despite advances in immunosuppressive management in lung transplantation, acute and chronic rejection remain challenging. One under-studied area of research is the role of the microbiota and its effects on alloimmunity and allograft rejection. Prior work has shown that the microbiota modulates innate and adaptive immunity through pathways such as the induction of suppressive Foxp3+ CD4+ regulatory T cells (Treg). Guo et al in this issue of the AJT demonstrate vendor-specific differences in lung allograft rejection in a minor histocompatibility mismatch murine model, and these differences are ameliorated by antibiotics. The authors thus focused on the microbiota and investigated whether the association between microbiota and lung allograft rejection may be related to microbiota-induced alterations in Treg responses. This article is protected by copyright. All rights reserved.

RevDate: 2019-08-13

Lechner K, von Schacky C, McKenzie AL, et al (2019)

Lifestyle factors and high-risk atherosclerosis: Pathways and mechanisms beyond traditional risk factors.

European journal of preventive cardiology [Epub ahead of print].

Despite major efforts to reduce atherosclerotic cardiovascular disease (ASCVD) burden with conventional risk factor control, significant residual risk remains. Recent evidence on non-traditional determinants of cardiometabolic health has advanced our understanding of lifestyle-disease interactions. Chronic exposure to environmental stressors like poor diet quality, sedentarism, ambient air pollution and noise, sleep deprivation and psychosocial stress affect numerous traditional and non-traditional intermediary pathways related to ASCVD. These include body composition, cardiorespiratory fitness, muscle strength and functionality and the intestinal microbiome, which are increasingly recognized as major determinants of cardiovascular health. Evidence points to partially overlapping mechanisms, including effects on inflammatory and nutrient sensing pathways, endocrine signalling, autonomic function and autophagy. Of particular relevance is the potential of low-risk lifestyle factors to impact on plaque vulnerability through altered adipose tissue and skeletal muscle phenotype and secretome. Collectively, low-risk lifestyle factors cause a set of phenotypic adaptations shifting tissue cross-talk from a proinflammatory milieu conducive for high-risk atherosclerosis to an anti-atherogenic milieu. The ketone body ß-hydroxybutyrate, through inhibition of the NLRP-3 inflammasome, is likely to be an intermediary for many of these observed benefits. Adhering to low-risk lifestyle factors adds to the prognostic value of optimal risk factor management, and benefit occurs even when the impact on conventional risk markers is discouragingly minimal or not present. The aims of this review are (a) to discuss novel lifestyle risk factors and their underlying biochemical principles and (b) to provide new perspectives on potentially more feasible recommendations to improve long-term adherence to low-risk lifestyle factors.

RevDate: 2019-08-13

Daubert DM, BF Weinstein (2019)

Biofilm as a risk factor in implant treatment.

Periodontology 2000, 81(1):29-40.

This article summarizes the microbiological findings at dental implants, drawing distinctions between the peri-implant microbiome and the periodontal microbiome, and summarizes what is known regarding biofilm as a risk factor for specific stages of implant treatment. Targeted microbial analysis is reviewed as well as the latest results from open-ended sequencing of the peri-implant flora. At this time there remains a lack of consensus for a specific microbial profile that is associated with peri-implantitis, suggesting that there may be other factors which influence the microbiome such as titanium surface dissolution. Therapeutic interventions to address the biofilm are presented at the preoperative, perioperative, and postoperative stages. Evidence supports that perioperative chlorhexidine reduces biofilm-related implant complications and failure. Regular maintenance for dental implants is also shown to reduce peri-implant mucositis and implant failure. Maintenance procedures should aim to disrupt the biofilm without damaging the titanium dioxide surface layer in an effort to prevent further oxidation. Evidence supports the use of glycine powder air polishing as a valuable adjunct to conventional therapies for use at implant maintenance visits. For the treatment of peri-implantitis, nonsurgical therapy has not been shown to be effective, and while surgical intervention is not always predictable, it has been shown to be superior to nonsurgical treatment for decontamination of the implant surface that is not covered by bone.

RevDate: 2019-08-13

Cardenas-de la Garza JA, Haidari W, SR Feldman (2019)

Microbiome, probiotics and dermatology.

The British journal of dermatology [Epub ahead of print].

RevDate: 2019-08-13

Hu A, Lu Y, Hernández García M, et al (2019)

Targeted Metatranscriptomics of Soil Microbial Communities with Stable Isotope Probing.

Methods in molecular biology (Clifton, N.J.), 2046:163-174.

Metatranscriptomics is a powerful tool for capturing gene expression patterns in microbial communities and investigating their responses to environmental conditions. Stable isotope probing (SIP) is a method to target specific functional groups of microorganisms in environmental samples. The combination of RNA-SIP with metatranscriptomic analysis enhances the detection and identification of mRNA from target microorganisms. In this chapter we provide a protocol for RNA-SIP, mRNA enrichment, and mRNA preparation for high-throughput sequencing using an example of targeting methanotrophs in rice field soil.

RevDate: 2019-08-13

Ghori NU, Moreira-Grez B, Vuong P, et al (2019)

RNA Stable Isotope Probing (RNA-SIP).

Methods in molecular biology (Clifton, N.J.), 2046:31-44.

Stable isotope probing is a combined molecular and isotopic technique used to probe the identity and function of uncultivated microorganisms within environmental samples. Employing stable isotopes of common elements such as carbon and nitrogen, RNA-SIP exploits an increase in the buoyant density of RNA caused by the active metabolism and incorporation of heavier mass isotopes into the RNA after cellular utilization of labeled substrates pulsed into the community. Labeled RNAs are subsequently separated from unlabeled RNAs by density gradient centrifugation followed by identification of the RNAs by sequencing. Therefore, RNA stable isotope probing is a culture-independent technique that provides simultaneous information about microbiome community, composition and function. This chapter presents the detailed protocol for performing an RNA-SIP experiment, including the formation, ultracentrifugation, and fractional analyses of stable isotope-labeled RNAs extracted from environmental samples.

RevDate: 2019-08-13

Knapp GC, Sharma A, Olopade B, et al (2019)

An Exploratory Analysis of Fecal Immunochemical Test Performance for Colorectal Cancer Screening in Nigeria.

World journal of surgery pii:10.1007/s00268-019-05100-0 [Epub ahead of print].

INTRODUCTION: The fecal immunochemical test (FIT) for hemoglobin is recommended for colorectal cancer (CRC) screening in resource-limited environments. However, there are several unique variables that may alter FIT performance in this setting, including endemic intestinal parasites and high ambient temperature. This prospective study evaluated the performance of FIT in asymptomatic, average-risk individuals of screening age in rural Nigeria.

METHODS: Three hundred and twenty-four community volunteers completed a questionnaire and provided stool specimens for parasitology and microbiome analysis. Specimens were frozen and stored at -80 °C. Of 324 subjects, 139 met criteria for average-risk CRC screening and had a stool sample for analysis. These were thawed and tested with a qualitative FIT. Specimens positive for occult blood were retested every two days to evaluate the impact of time and temperature on test performance.

RESULTS: Of 139 individuals, 69 (49.6%) were positive for intestinal parasites and 10 (7.2%) were positive for occult blood. The most common pathogen was Cryptosporidium (40.6%). Among patients with intestinal parasites, 10.1% (7/69) had a positive FIT. Only 4.3% (3/70) of patients without parasites had a positive FIT (p = 0.208). On bivariate analysis, sociodemographic variables were not associated with a positive FIT result. Thirty percent (3/10) of the FIT-positive specimens became FIT-negative with routine storage.

CONCLUSION: Although a positive FIT result was more common in those with parasitic infection, the relationship was not significant in this small cohort. The impact of high ambient temperature on test positivity may necessitate shorter processing time guidelines for equatorial countries. Additional prospective studies are needed to validate FIT performance in Nigeria.

RevDate: 2019-08-13

Bockoven AA, Bondy EC, Flores MJ, et al (2019)

What Goes Up Might Come Down: the Spectacular Spread of an Endosymbiont Is Followed by Its Decline a Decade Later.

Microbial ecology pii:10.1007/s00248-019-01417-4 [Epub ahead of print].

Facultative, intracellular bacterial symbionts of arthropods may dramatically affect host biology and reproduction. The length of these symbiont-host associations may be thousands to millions of years, and while symbiont loss is predicted, there have been very few observations of a decline of symbiont infection rates. In a population of the sweet potato whitefly species (Bemisia tabaci MEAM1) in Arizona, USA, we documented the frequency decline of a strain of Rickettsia in the Rickettsia bellii clade from near-fixation in 2011 to 36% of whiteflies infected in 2017. In previous studies, Rickettsia had been shown to increase from 1 to 97% from 2000 to 2006 and remained at high frequency for at least five years. At that time, Rickettsia infection was associated with both fitness benefits and female bias. In the current study, we established matrilines of whiteflies from the field (2016, Rickettsia infection frequency = 58%) and studied (a) Rickettsia vertical transmission, (b) fitness and sex ratios associated with Rickettsia infection, (c) symbiont titer, and (d) bacterial communities within whiteflies. The vertical transmission rate was high, approximately 98%. Rickettsia infection in the matrilines was not associated with fitness benefits or sex ratio bias and appeared to be slightly costly, as more Rickettsia-infected individuals produced non-hatching eggs. Overall, the titer of Rickettsia in the matrilines was lower in 2016 than in the whiteflies collected in 2011, but the titer distribution appeared bimodal, with high- and low-titer lines, and constancy of the average titer within lines over three generations. We found neither association between Rickettsia titer and fitness benefits or sex ratio bias nor evidence that Rickettsia was replaced by another secondary symbiont. The change in the interaction between symbiont and host in 2016 whiteflies may explain the drop in symbiont frequency we observed.

RevDate: 2019-08-13

Brown RE, Short SP, CS Williams (2018)

Colorectal Cancer and Metabolism.

Current colorectal cancer reports, 14(6):226-241.

Purpose of Review: Metabolic reprogramming is essential for the rapid proliferation of cancer cells and is thus recognized as a hallmark of cancer. In this review, we will discuss the etiologies and effects of metabolic reprogramming in colorectal cancer.

Recent Findings: Changes in cellular metabolism may precede the acquisition of driver mutations ultimately leading to colonocyte transformation. Oncogenic mutations and loss of tumor suppressor genes further reprogram CRC cells to upregulate glycolysis, glutaminolysis, one-carbon metabolism, and fatty acid synthesis. These metabolic changes are not uniform throughout tumors, as subpopulations of tumor cells may rely on different pathways to adapt to nutrient availability in the local tumor microenvironment. Finally, metabolic cross-communication between stromal cells, immune cells, and the gut microbiota enable CRC growth, invasion, and metastasis.

Summary: Altered cellular metabolism occurs in CRC at multiple levels, including in the cells that make up the bulk of CRC tumors, cancer stem cells, the tumor microenvironment, and host-microbiome interactions. This knowledge may inform the development of improved screening and therapeutics for CRC.

RevDate: 2019-08-13

Doan T, Hinterwirth A, Worden L, et al (2019)

Gut microbiome alteration in MORDOR I: a community-randomized trial of mass azithromycin distribution.

Nature medicine pii:10.1038/s41591-019-0533-0 [Epub ahead of print].

The MORDOR I trial1, conducted in Niger, Malawi and Tanzania, demonstrated that mass azithromycin distribution to preschool children reduced childhood mortality1. However, the large but simple trial design precluded determination of the mechanisms involved. Here we examined the gut microbiome of preschool children from 30 Nigerien communities randomized to either biannual azithromycin or placebo. Gut microbiome γ-diversity was not significantly altered (P = 0.08), but the relative abundances of two Campylobacter species, along with another 33 gut bacteria, were significantly reduced in children treated with azithromycin at the 24-month follow-up. Metagenomic analysis revealed functional differences in gut bacteria between treatment groups. Resistome analysis showed an increase in macrolide resistance gene expression in gut microbiota in communities treated with azithromycin (P = 0.004). These results suggest that prolonged mass azithromycin distribution to reduce childhood mortality reduces certain gut bacteria, including known pathogens, while selecting for antibiotic resistance.

RevDate: 2019-08-13

Anonymous (2019)

Vast pool of new proteins is found, thanks to the human microbiome.

Nature, 572(7769):287.

RevDate: 2019-08-13

Segata N (2019)

No bacteria found in healthy placentas.

Nature, 572(7769):317-318.

RevDate: 2019-08-13

He X, Parenti M, Grip T, et al (2019)

Fecal microbiome and metabolome of infants fed bovine MFGM supplemented formula or standard formula with breast-fed infants as reference: a randomized controlled trial.

Scientific reports, 9(1):11589 pii:10.1038/s41598-019-47953-4.

Human milk delivers an array of bioactive components that safeguard infant growth and development and maintain healthy gut microbiota. Milk fat globule membrane (MFGM) is a biologically functional fraction of milk increasingly linked to beneficial outcomes in infants through protection from pathogens, modulation of the immune system and improved neurodevelopment. In the present study, we characterized the fecal microbiome and metabolome of infants fed a bovine MFGM supplemented experimental formula (EF) and compared to infants fed standard formula (SF) and a breast-fed reference group. The impact of MFGM on the fecal microbiome was moderate; however, the fecal metabolome of EF-fed infants showed a significant reduction of several metabolites including lactate, succinate, amino acids and their derivatives from that of infants fed SF. Introduction of weaning food with either human milk or infant formula reduces the distinct characteristics of breast-fed- or formula-fed- like infant fecal microbiome and metabolome profiles. Our findings support the hypothesis that higher levels of protein in infant formula and the lack of human milk oligosaccharides promote a shift toward amino acid fermentation in the gut. MFGM may play a role in shaping gut microbial activity and function.

RevDate: 2019-08-13

Kobayashi A, Tsuchida S, Ueda A, et al (2019)

Role of coprophagy in the cecal microbiome development of an herbivorous bird Japanese rock ptarmigan.

The Journal of veterinary medical science [Epub ahead of print].

The transgenerational maintenance of symbiotic microbes that benefit host nutrition and health is evolutionarily advantageous. In some vertebrate lineages, coprophagy is used as a strategy for effectively transmitting microbes across generations. However, this strategy has still not been studied in birds. Accordingly, the aim of the present study was to evaluate the role of maternal cecal feces consumption by Japanese rock ptarmigan (Lagopus muta japonica) chicks as a strategy for acquiring essential gut microbes. Both the duration of coprophagy behavior by the chicks and the development process of the chick cecal microbiome (n=20 one- to three-week-old chicks, from three broods) were investigated. In all three broods, coprophagy behavior was only observed from 3 to 18 days of age. Furthermore, there was no significant difference in the number of bacterial operational taxonomic units (OTUs) in 1-week-old chicks (n=651) and adults (n=609), and most of the main OTUs observed in the adults were already present in the 1-week-old chicks. These results indicate that, in this precocial bird species, coprophagy may contribute to the early establishment of cecal bacteria that are essential for food digestion and, thus, chick survival. In fact, Japanese rock ptarmigan chicks consume the same food as their hens from the time of hatching. This behavior may have applications to ex-situ conservation.

RevDate: 2019-08-13

van Hecke O, Fuller A, Bankhead C, et al (2019)

Antibiotic exposure and 'response failure' for subsequent respiratory tract infections: an observational cohort study of UK preschool children in primary care.

The British journal of general practice : the journal of the Royal College of General Practitioners pii:bjgp19X705089 [Epub ahead of print].

BACKGROUND: Childhood antibiotic exposure has important clinically relevant implications. These include disruption to the microbiome, antibiotic resistance, and clinical workload manifesting as treatment 'failure'.

AIM: To examine the relationship between the number of antibiotic courses prescribed to preschool children for acute respiratory tract infections (RTI), in the preceding year, and subsequent RTIs that failed to respond to antibiotic treatment ('response failures').

DESIGN AND SETTING: A cohort study using UK primary care data from the Clinical Practice Research Datalink, 2009 to 2016.

METHOD: Children aged 12 to 60 months (1 to 5 years) who were prescribed an antibiotic for an acute RTI (upper and lower RTI or otitis media) were included. One random index antibiotic course for RTI per child was selected. Exposure was the number of antibiotic prescriptions for acute RTI up to 12 months before the index antibiotic prescription. The outcome was 'response failure' up to 14 days after index antibiotic prescription, defined as: subsequent antibiotic prescription; referral; hospital admission; death; or emergency department attendance within 3 days. The authors used logistic regression models to estimate the odds between antibiotic exposure and response failure.

RESULTS: Out of 114 329 children who were prescribed an antibiotic course for acute RTI, children who received ≥2 antibiotic courses for acute RTIs in the preceding year had greater odds of response failure; one antibiotic course: adjusted odds ratio (OR) 1.03 (95% confidence interval [CI] = 0.88 to 1.21), P = 0.67, n = 230 children; ≥2 antibiotic courses: adjusted OR 1.32 (CI = 1.04 to 1.66), P = 0.02, n = 97.

CONCLUSION: Childhood antibiotic exposure for acute RTI may be a good predictor for subsequent response failure (but not necessarily because of antibiotic treatment failure). Further research is needed to improve understanding of the mechanisms underlying response failure.

RevDate: 2019-08-13

Raghuvanshi R, Grayson AG, Schena I, et al (2019)

Microbial Transformations of Organically Fermented Foods.

Metabolites, 9(8): pii:metabo9080165.

Fermenting food is an ancient form of preservation ingrained many in human societies around the world. Westernized diets have moved away from such practices, but even in these cultures, fermented foods are seeing a resurgent interested due to their believed health benefits. Here, we analyze the microbiome and metabolome of organically fermented vegetables, using a salt brine, which is a common 'at-home' method of food fermentation. We found that the natural microbial fermentation had a strong effect on the food metabolites, where all four foods (beet, carrot, peppers and radishes) changed through time, with a peak in molecular diversity after 2-3 days and a decrease in diversity during the final stages of the 4-day process. The microbiome of all foods showed a stark transition from one that resembled a soil community to one dominated by Enterobacteriaceae, such as Erwinia spp., within a single day of fermentation and increasing amounts of Lactobacillales through the fermentation process. With particular attention to plant natural products, we observed significant transformations of polyphenols, triterpenoids and anthocyanins, but the degree of this metabolism depended on the food type. Beets, radishes and peppers saw an increase in the abundance of these compounds as the fermentation proceeded, but carrots saw a decrease through time. This study showed that organically fermenting vegetables markedly changed their chemistry and microbiology but resulted in high abundance of Enterobacteriaceae which are not normally considered as probiotics. The release of beneficial plant specialized metabolites was observed, but this depended on the fermented vegetable.

RevDate: 2019-08-13

Derovs A, Laivacuma S, A Krumina (2019)

Targeting Microbiota: What Do We Know about It at Present?.

Medicina (Kaunas, Lithuania), 55(8): pii:medicina55080459.

The human microbiota is a variety of different microorganisms. The composition of microbiota varies from host to host, and it changes during the lifetime. It is known that microbiome may be changed because of a diet, bacteriophages and different processes for example, such as inflammation. Like all other areas of medicine, there is a continuous growth in the area of microbiology. Different microbes can reside in all sites of a human body, even in locations that were previously considered as sterile; for example, liver, pancreas, brain and adipose tissue. Presently one of the etiological factors for liver disease is considered to be pro-inflammatory changes in a host's organism. There are lot of supporting data about intestinal dysbiosis and increased intestinal permeability and its effect on development of liver disease pointing to the gut-liver axis. The gut-liver axis affects pathogenesis of many liver diseases, such as chronic hepatitis B, chronic hepatitis C, alcoholic liver disease, non-alcoholic liver disease, non-alcoholic steatohepatitis, liver cirrhosis and hepatocellular carcinoma. Gut microbiota has been implicated in the regulation of brain health, emphasizing the gut-brain axis. Also, experiments with mice showed that microorganisms have significant effects on the blood-brain barrier integrity. Microbiota can modulate a variety of mechanisms through the gut-liver axis and gut-brain axis. Normal intestinal flora impacts the health of a host in many positive ways, but there is now significant evidence that intestinal microbiota, especially altered, have the ability to impact the pathologies of many diseases through different inflammatory mechanisms. At this point, many of the pathophysiological reactions in case of microbial disbyosis are still unclear.

RevDate: 2019-08-13

Tarantola A, Horwood PF, Goarant C, et al (2019)

Counting Oceanians of Non-European, Non-Asian Descent (ONENA) in the South Pacific to Make Them Count in Global Health.

Tropical medicine and infectious disease, 4(3): pii:tropicalmed4030114.

Several diseases and vulnerabilities associated with genetic or microbial factors are more frequent among populations of Oceanian, Non-European, Non-Asian descent (ONENA). ONENA are specific and have long been isolated geographically. To our knowledge, there are no published official, quantitative, aggregated data on the populations impacted by these excess vulnerabilities in Oceania. We searched official census reports for updated estimates of the total population for each of the Pacific Island Countries and Territories (including Australia) and the US State of Hawaii, privileging local official statistical or censual sources. We multiplied the most recent total population estimate by the cumulative percentage of the ONENA population as determined in official reports. Including Australia and the US State of Hawaii, Oceania counts 27 countries and territories, populated in 2016 by approximately 41 M inhabitants (17 M not counting Australia) among which approximately 12.5 M (11.6 M not counting Australia) consider themselves of entire or partial ONENA ancestry. Specific genetic and microbiome traits of ONENA may be unique and need further investigation to adjust risk estimates, risk prevention, diagnostic and therapeutic strategies, to the benefit of populations in the Pacific and beyond.

RevDate: 2019-08-12

Bajaj JS, Sharma A, PK Dudeja (2019)

Targeting Gut Microbiome Interactions in Service-related Gastrointestinal and Liver Diseases of Veterans: Meeting Summary.

Gastroenterology pii:S0016-5085(19)41210-9 [Epub ahead of print].

RevDate: 2019-08-12

Luo L, Guo C, Wang L, et al (2019)

Negative Plant-Soil Feedback Driven by Re-assemblage of the Rhizosphere Microbiome With the Growth of Panax notoginseng.

Frontiers in microbiology, 10:1597.

There is a concerted understanding of the accumulation of soil pathogens as the major driving factor of negative plant-soil feedback (NPSF). However, our knowledge of the connection between plant growth, pathogen build-up and soil microbiome assemblage is limited. In this study, significant negative feedback between the soil and sanqi (Panax notoginseng) was found, which were caused by the build-up of the soil-borne pathogens Fusarium oxysporum, F. solani, and Monographella cucumerina. Soil microbiome analysis revealed that the rhizospheric fungal and bacterial communities were changed with the growth of sanqi. Deep analysis of the phylum and genus levels corroborated that rhizospheric fungal Ascomycota, including the soil-borne pathogens F. oxysporum, F. solani, and especially M. cucumerina, were significantly enriched with the growth of sanqi. However, the bacteria Firmicutes and Acidobacteria, including the genera Pseudomonas, Bacillus, Acinetobacter and Burkholderia, were significantly suppressed with the growth of sanqi. Using microbial isolation and in vitro dual culture tests, we found that most isolates derived from the suppressed bacterial genera showed strong antagonistic ability against the growth of sanqi soil-borne pathogens. Interestingly, inoculation of these suppressed isolates in consecutively cultivated soil could significantly alleviate NPSF. In summary, sanqi growth can suppress antagonistic bacteria through re-assemblage of the rhizosphere microbiome and cause the accumulation of soil-borne pathogens, eventually building negative feedback loops between the soil and plants.

RevDate: 2019-08-12

Yurgel SN, Nearing JT, Douglas GM, et al (2019)

Metagenomic Functional Shifts to Plant Induced Environmental Changes.

Frontiers in microbiology, 10:1682.

The Vaccinium angustifolium (wild blueberry) agricultural system involves transformation of the environment surrounding the plant to intensify plant propagation and to improve fruit yield, and therefore is an advantageous model to study the interaction between soil microorganisms and plant-host interactions. We studied this system to address the question of a trade-off between microbial adaptation to a plant-influenced environment and its general metabolic capabilities. We found that many basic metabolic functions were similarly represented in bulk soil and rhizosphere microbiomes overall. However, we identified a niche-specific difference in functions potentially beneficial for microbial survival in the rhizosphere but that might also reduce the ability of microbes to withstand stresses in bulk soils. These functions could provide the microbiome with additional capabilities to respond to environmental fluctuations in the rhizosphere triggered by changes in the composition of root exudates. Based on our analysis we hypothesize that the rhizosphere-specific pathways involved in xenobiotics biodegradation could provide the microbiome with functional flexibility to respond to plant stress status.

RevDate: 2019-08-12

Abdelfattah A, Sanzani SM, Wisniewski M, et al (2019)

Revealing Cues for Fungal Interplay in the Plant-Air Interface in Vineyards.

Frontiers in plant science, 10:922.

Plant-associated microorganisms play a crucial role in plant health and productivity. Belowground microbial diversity is widely reported as a major factor in determining the composition of the plant microbiome. In contrast, much less is known about the role of the atmosphere in relation to the plant microbiome. The current study examined the hypothesis that the atmospheric microbiome influences the composition of fungal communities of the aboveground organs (flowers, fruit, and leaves) of table grape and vice versa. The atmosphere surrounding grape plantings exhibited a significantly higher level of fungal diversity relative to the nearby plant organs and shared a higher number of phylotypes (5,536 OTUs, 40.3%) with the plant than between organs of the same plant. Using a Bayesian source tracking approach, plant organs were determined to be the major source of the atmospheric fungal community (92%). In contrast, airborne microbiota had only a minor contribution to the grape microbiome, representing the source of 15, 4, and 35% of the fungal communities of leaves, flowers, and fruits, respectively. Moreover, data indicate that plant organs and the surrounding atmosphere shared a fraction of each other's fungal communities, and this shared pool of fungal taxa serves as a two-way reservoir of microorganisms. Microbial association analysis highlighted more positive than negative interactions between fungal phylotypes. Positive interactions were more common within the same environment, while negative interactions appeared to occur more frequently between different environments, i.e., atmosphere, leaf, flower, and fruit. The current study revealed the interplay between the fungal communities of the grape phyllosphere with the surrounding air. Plants were identified as a major source of recruitment for the atmospheric microbiome, while the surrounding atmosphere contributed only a small fraction of the plant fungal community. The results of the study suggested that the plant-air interface modulates the plant recruitment of atmospheric fungi, taking a step forward in understanding the plant holobiont assembly and how the atmosphere surrounding plants plays a role in this process. The impact of plants on the atmospheric microbiota has several biological and epidemiological implications for plants and humans.

RevDate: 2019-08-12

Robinson JI, Weir WH, Crowley JR, et al (2019)

Metabolomic networks connect host-microbiome processes to human Clostridioides difficile infections.

The Journal of clinical investigation, 130: pii:126905.

Clostridioides difficile infection (CDI) accounts for a substantial proportion of deaths attributable to antibiotic-resistant bacteria in the United States. Although C. difficile can be an asymptomatic colonizer, its pathogenic potential is most commonly manifested in patients with antibiotic-modified intestinal microbiomes. In a cohort of 186 hospitalized patients, we showed that host and microbe-associated shifts in fecal metabolomes had the potential to distinguish patients with CDI from those with non-C. difficile diarrhea and C. difficile colonization. Patients with CDI exhibited a chemical signature of Stickland amino acid fermentation that was distinct from those of uncolonized controls. This signature suggested that C. difficile preferentially catabolizes branched chain amino acids during CDI. Unexpectedly, we also identified a series of noncanonical, unsaturated bile acids that were depleted in patients with CDI. These bile acids may derive from an extended host-microbiome dehydroxylation network in uninfected patients. Bile acid composition and leucine fermentation defined a prototype metabolomic model with potential to distinguish clinical CDI from asymptomatic C. difficile colonization.

RevDate: 2019-08-12

Tibbs TN, Lopez LR, JC Arthur (2019)

The influence of the microbiota on immune development, chronic inflammation, and cancer in the context of aging.

Microbial cell (Graz, Austria), 6(8):324-334 pii:MIC0178E158.

From birth, the microbiota plays an essential role in human development by educating host immune responses. Proper maturation of the immune system perturbs chronic inflammation and the pathogenesis of disease by preventing inappropriate immune responses. While many have detailed the roles of specific microbial groups in immune development and human disease, it remains to be elucidated how the microbiota influences the immune system during aging. Furthermore, it is not yet understood how age-related changes to the microbiota and immune system influence the development of age-related diseases. In this review, we outline the role of the microbiota in immune system development as well as functional changes that occur to immune cell populations during immunosenescence. In addition, we highlight how commensal microbes influence the pathogenesis of cancer, a prominent disease of aging. The information provided herein suggests that age-related changes to the microbiota and immune system should be considered in disease treatment and prevention strategies.

RevDate: 2019-08-12

Kauser I, Ciesielski M, RS Poretsky (2019)

Ultraviolet disinfection impacts the microbial community composition and function of treated wastewater effluent and the receiving urban river.

PeerJ, 7:e7455 pii:7455.

Background: In the United States, an estimated 14,748 wastewater treatment plants (WWTPs) provide wastewater collection, treatment, and disposal service to more than 230 million people. The quality of treated wastewater is often assessed by the presence or absence of fecal indicator bacteria. UV disinfection of wastewater is a common final treatment step used by many wastewater treatment plants in order to reduce fecal coliform bacteria and other pathogens; however, its potential impacts on the total effluent bacterial community are seemingly varied. This is especially important given that urban WWTPs typically return treated effluent to coastal and riverine environments and thus are a major source of microorganisms, genes, and chemical compounds to these systems. Following rainfall, stormflow conditions can result in substantial increases to effluent flow into combined systems.

Methods: Here, we conducted a lab-scale UV disinfection on WWTP effluent using UV dosage of 100 mJ/cm2 and monitored the active microbiome in UV-treated effluent and untreated effluent over the course of 48 h post-exposure using 16S rRNA sequencing. In addition, we simulated stormflow conditions with effluent UV-treated and untreated effluent additions to river water and compared the microbial communities to those in baseflow river water. We also tracked the functional profiles of genes involved in tetracycline resistance (tetW) and nitrification (amoA) in these microcosms using RT-qPCR.

Results: We showed that while some organisms, such as members of the Bacteroidetes, are inhibited by UV disinfection and overall diversity of the microbial community decreases following treatment, many organisms not only survive, but remain active. These include common WWTP-derived organisms such as Comamonadaceae and Pseudomonas. When combined with river water to mimic stormflow conditions, these organisms can persist in the environment and potentially enhance microbial functions such as nitrification and antibiotic resistance.

RevDate: 2019-08-12

Martin J (2019)

Reproducibility: the search for microbiome standards.

BioTechniques [Epub ahead of print].

The reproducibility crisis is resulting in a lot of discussion in various scientific fields. This feature explores the latest technologies, methods and projects relevant to the biological laboratory and aiming to solve this problem.

RevDate: 2019-08-12

Veit-Rubin N, De Tayrac R, Cartwright R, et al (2019)

Abnormal vaginal microbiome associated with vaginal mesh complications.

Neurourology and urodynamics [Epub ahead of print].

AIMS: To identify differences in the vaginal microbiomes of women after transvaginal mesh (TVM) surgery for pelvic organ prolapse with and without mesh-associated complications.

METHODS: Patients with complications were eligible as cases, patients without as controls. DNA was isolated and the V1-2 region of the 16S ribosomal RNA gene was amplified and sequenced. Overall richness was quantified using Chao1. Overall diversity was expressed as Shannon diversity and screened for group differences using analysis of variance. Multivariate differences among groups were evaluated with functions from R.

RESULTS: We recruited 14 patients after mesh exposure, 5 after contraction, and 21 as controls. The average number of operational taxonomic unit was 74.79 (SD ± 63.91) for controls, 57.13 (SD ± 58.74) after exposures, and 92.42 (SD ± 50.01) after contractions. Total 89.6% of bacteria in controls, 86.4% in previous exposures, and 81.3% in contractions were classified as either Firmicutes, Proteobacteria, or Actinobacteria (P < .001). Veillonella spp. was more abundant in patients after contraction (P = .045). The individual microbiomes varied, and we did not detect any significant differences in richness but a trend towards higher diversity with complications.

CONCLUSIONS: The presence of Veillonella spp. could be associated with mesh contraction. Our study did not identify vaginal microbiotic dysbiosis as a factor associated with exposure. Larger cohort studies would be needed to distinguish the vaginal microbiome of women predisposed to mesh-related complications for targeted phenotyping of patients who could benefit from TVM surgery.

RevDate: 2019-08-12

Pietzke M, Meiser J, A Vazquez (2019)

Formate metabolism in health and disease.

Molecular metabolism pii:S2212-8778(19)30431-4 [Epub ahead of print].

BACKGROUND: Formate is a one-carbon molecule at the crossroad between cellular and whole body metabolism, between host and microbiome metabolism, and between nutrition and toxicology. This centrality confers formate with a key role in human physiology and disease that is currently unappreciated.

SCOPE OF REVIEW: Here we review the scientific literature on formate metabolism, highlighting cellular pathways, whole body metabolism, and interactions with the diet and the gut microbiome. We will discuss the relevance of formate metabolism in the context of embryonic development, cancer, obesity, immunometabolism, and neurodegeneration.

MAJOR CONCLUSIONS: We will conclude with an outlook of some open questions bringing formate metabolism into the spotlight.

RevDate: 2019-08-12

Abreu DPB, Peixoto MP, Luz HR, et al (2019)

Two for the price of one: Co-infection with Rickettsia bellii and spotted fever group Rickettsia in Amblyomma (Acari: Ixodidae) ticks recovered from wild birds in Brazil.

Ticks and tick-borne diseases pii:S1877-959X(19)30050-0 [Epub ahead of print].

The bacterium Rickettsia bellii has been detected in 25 species of ticks in the American continents, but its pathogenic potential is considered as undetermined. A possible role for this species in the phenomenon of transovarial exclusion of pathogenic members of the spotted fever group (SFG) of Rickettsia has been suggested and co-infections with pathogenic species have been reported infrequently in both North and South America. Traditional methods for the molecular detection of rickettsial agents in ticks focus largely on the identification of sequences found in SFG Rickettsia, an approach that may overlook the presence of co-infections with R. bellii. Two novel, species-specific polymerase chain reaction (PCR) assays, targeting the genes encoding the surface cell antigen (Sca), autotransporter proteins sca9 and sca14, were developed and validated for the detection of R. bellii using 150 Amblyomma ticks collected from wild birds in Brazil. Co-infection of R. bellii infected ticks was evaluated using a novel PCR assay targeting the ompA sequence characteristic of SFG Rickettsia. Preliminary species-level identification was achieved by restriction fragment length polymorphism (RFLP) analysis and subsequently confirmed by sequencing of amplicons. Nine out of seventy-three Amblyomma longirostre and one of two Amblyomma calcaratum ticks were shown to be co-infected with R. bellii and Rickettsia amblyommatis, while two out of sixty-seven Amblyomma sp. haplotype Nazaré ticks were recorded as co-infected with R. bellii and the Rickettsia parkeri-like bacterium, strain ApPR. Interestingly, our data represent the first records of R. bellii in association with A. calcaratum and Amblyomma sp. haplotype Nazaré. The novel PCR-RFLP systems reported herein, provide an alternative, rapid and cost-efficient (relative to strategies based on sequencing or real-time PCR), approach to evaluate rickettsial co-infection of ticks, a potentially significant phenomenon that has most likely been underestimated to date.

RevDate: 2019-08-11

Chen J, Yu B, Chen D, et al (2019)

Changes of porcine gut microbiota in response to dietary chlorogenic acid supplementation.

Applied microbiology and biotechnology pii:10.1007/s00253-019-10025-8 [Epub ahead of print].

Chlorogenic acids (CGA), the most abundant natural polyphenol present in human diet and plants, have attracted considerable research interest because of their broad bioactivities including the antimicrobial activity. However, little is known about their influences on intestinal bacterial communities. Here, we described a response in intestinal microbiome to CGA using a porcine model. Twenty-four weaned pigs were allotted to two groups and fed with a basal diet or a basal diet containing 1000 mg/kg CGA. Results showed that CGA significantly increased the length of the small intestine (P < 0.05) and enhanced the activity of diamine oxidase (DAO) and the concentration of MHC-II in the jejunal and ileal mucosa (P < 0.05). Moreover, the acetate concentration in ileum and cecum digesta, and the propionate and butyrate concentrations in the cecum digesta, were significantly elevated by CGA (P < 0.05). Interestingly, CGA significantly increased the total 16S rRNA gene copies and bacterial alpha diversity in the cecum (P < 0.05). The relative abundance of bacteria from phyla Firmicutes and Bacteroidetes was increased in the cecum digesta (P < 0.05), whereas the abundance of bacteria from phylum Protebacteria was decreased by CGA (P < 0.05). Importantly, pigs on CGA-containing diet had higher abundance of Lactobacillus spp., Prevotella spp., Anaerovibrio spp., and Alloprevotella spp. in the cecum (P < 0.05). Not only did our study suggest a synergic response of intestinal barrier function and microbiota to the CGA, but the result will also contribute to understanding of the mechanisms behind the CGA-modulated gut health.

RevDate: 2019-08-11

Acker KP, Wong Fok Lung T, West E, et al (2019)

Strains of Staphylococcus aureus that Colonize and Infect Skin Harbor Mutations in Metabolic Genes.

iScience, 19:281-290 pii:S2589-0042(19)30264-0 [Epub ahead of print].

Staphylococcus aureus is the most common cause of skin and soft tissue infections, yet the bacterial genetic changes associated with adaptation to human skin are not well characterized. S. aureus strains isolated from patients with chronic skin colonization and intermittent infection were used to determine the staphylococcal genotypes or phenotypes associated with adaptation to human skin. We demonstrate that polymorphisms in metabolic genes, particularly those involved in the tricarboxylic acid cycle, the fumarate-succinate axis, and the generation of terminal electron transporters, are unexpectedly common. These skin-adapted strains activated glycolysis and hypoxia-inducible factor-1α, interleukin (IL)-1β, and IL-18 release from keratinocytes and promoted dermatopathology equivalent to a methicillin-resistant Staphylococcus aureus USA300 control in a murine model of infection. However, in contrast to USA300, a skin-adapted isolate failed to generate protection from a secondary infectious challenge. Within the context of human skin, there appears to be selection for S. aureus metabolic adaptive changes that promote glycolysis and maintain pathogenicity.

RevDate: 2019-08-11

Li JW, Fang B, Pang GF, et al (2019)

Age- and diet-specific effects of chronic exposure to chlorpyrifos on hormones, inflammation and gut microbiota in rats.

Pesticide biochemistry and physiology, 159:68-79.

Chlorpyrifos is a pesticide frequently detected in food and has been reported to disturb endocrine and gut health, which was regulated by gut microbiota and enteroendocrine cells. In this study, newly weaned (3 week) and adult (8 week) male rats fed a normal- or high- fat diet were chronically exposed to 0.3 mg chlorpyrifos/kg bodyweight/day. The effects of chlorpyrifos exposure on serum hormone levels, proinflammatory cytokines and gut microbiota were evaluated. Chronic exposure to chlorpyrifos significantly decreased the concentrations of luteinizing hormone, follicule stimulating hormone and testosterone, which was found only in the normal-fat diet. The counteracted effect of high-fat diet was also found in gut hormones and proinflammatory cytokines. Significantly higher concentrations of glucagon-like peptide-1, pancreatic polypeptide, peptide tyrosine tyrosine (PYY), ghrelin, gastric inhibitory poly-peptide, IL-6, monocyte chemoattractant protein-1, and TNF-α were found in rats exposed to chlorpyrifos beginning at newly weaned, whereas only the PYY, ghrelin and IL-6 concentrations increased significantly in rats exposed in adulthood. Furthermore, a decrease in epinephrine induced by chlorpyrifos exposure was found in rats exposed to chlorpyrifos beginning at newly weaned, regardless of their diet. Chlorpyrifos-induced disturbances in the microbiome community structure were more apparent in rats fed a high-fat diet and exposed beginning at newly weaned. The affected bacteria included short-chain fatty acid-producing bacteria (Romboutsia, Turicibacter, Clostridium sensu stricto 1, norank_f_Coriobacteriaceae, Faecalibaculum, Parasutterella and norank_f__Erysipelotrichaceae), testosterone-related genus (Turicibacter, Brevibacterium), pathogenic bacteria (Streptococcus), and inflammation-related bacteria (unclassified_f__Ruminococcaceae, Ruminococcaceae_UCG-009, Parasutterella, Oscillibacter), which regulated the endocrine system via the hypothalamic-pituitary-adrenal axis, as well as the immune response and gut barrier. Early exposure accelerated the endocrine-disturbing effect and immune responses of chlorpyrifos, although these effects can be eased or recovered by a high-fat diet. This study helped clarify the relationship between disrupted endocrine function and gut microbiota dysbiosis induced by food contaminants such as pesticides.

RevDate: 2019-08-10

Shamoon M, Martin NM, C L O'Brien (2019)

Recent Advances in Gut Microbiota Mediated Therapeutic Targets in Inflammatory Bowel Diseases: Emerging Modalities for Future Pharmacological Implications.

Pharmacological research pii:S1043-6618(19)30344-5 [Epub ahead of print].

The inflammatory bowel diseases (IBDs) are chronic inflammatory conditions, which are increasing in prevalence worldwide. The IBDs are thought to result from an aberrant immune response to gut microbes in genetically susceptible individuals. Dysbiosis of the gut microbiome, both functional and compositional, promotes patient susceptibility to colonization by pathobionts. Manipulating gut microbial communities and gut microbiota-immune system interactions to restore gut homeostasis or reduce inflammation are appealing therapeutic models. We discuss the therapeutic potential of precision microbiota editing, natural and engineered probiotics, the use of gut microbiota-derived metabolites in colitogenic phenotypes, and intestinal stem cells, in maintaining gut microbiota balance, restoring the mucosal barrier, and having positive immunomodulatory effects in experimental IBD. This review highlights that we are only just beginning to understand the complexity of the microbiota and how it can be manipulated for health benefits, including treatment and prevention of the clinical IBDs in future.

RevDate: 2019-08-10

Engevik M, J Versalovic (2019)

Taking a Closer Look at the Biogeography of the Human Gastrointestinal Microbiome.

RevDate: 2019-08-10

Bascuñán KA, Araya M, Roncoroni L, et al (2019)

Dietary Gluten as a Conditioning Factor of the Gut Microbiota in Celiac Disease.

Advances in nutrition (Bethesda, Md.) pii:5545662 [Epub ahead of print].

The gut microbiota plays a relevant role in determining an individual's health status, and the diet is a major factor in modulating the composition and function of gut microbiota. Gluten constitutes an essential dietary component in Western societies and is the environmental trigger of celiac disease. The presence/absence of gluten in the diet can change the diversity and proportions of the microbial communities constituting the gut microbiota. There is an intimate relation between gluten metabolism and celiac disease pathophysiology and gut microbiota; their interrelation defines intestinal health and homeostasis. Environmental factors modify the intestinal microbiota and, in turn, its changes modulate the mucosal and immune responses. Current evidence from studies of young and adult patients with celiac disease increasingly supports that dysbiosis (i.e., compositional and functional alterations of the gut microbiome) is present in celiac disease, but to what extent this is a cause or consequence of the disease and whether the different intestinal diseases (celiac disease, ulcerative colitis, Crohn disease) have specific change patterns is not yet clear. The use of bacterial-origin enzymes that help completion of gluten digestion is of interest because of the potential application as coadjuvant in the current treatment of celiac disease. In this narrative review, we address the current knowledge on the complex interaction between gluten digestion and metabolism, celiac disease, and the intestinal microbiota.

RevDate: 2019-08-10

Bolyen E, Rideout JR, Dillon MR, et al (2019)

Author Correction: Reproducible, interactive, scalable and extensible microbiome data science using QIIME 2.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

RevDate: 2019-08-10

Russell JT, Roesch LFW, Ördberg M, et al (2019)

Genetic risk for autoimmunity is associated with distinct changes in the human gut microbiome.

Nature communications, 10(1):3621 pii:10.1038/s41467-019-11460-x.

Susceptibility to many human autoimmune diseases is under strong genetic control by class II human leukocyte antigen (HLA) allele combinations. These genes remain by far the greatest risk factors in the development of type 1 diabetes and celiac disease. Despite this, little is known about HLA influences on the composition of the human gut microbiome, a potential source of environmental influence on disease. Here, using a general population cohort from the All Babies in Southeast Sweden study, we report that genetic risk for developing type 1 diabetes autoimmunity is associated with distinct changes in the gut microbiome. Both the core microbiome and beta diversity differ with HLA risk group and genotype. In addition, protective HLA haplotypes are associated with bacterial genera Intestinibacter and Romboutsia. Thus, general population cohorts are valuable in identifying potential environmental triggers or protective factors for autoimmune diseases that may otherwise be masked by strong genetic control.

RevDate: 2019-08-10

Thingholm LB, Rühlemann MC, Koch M, et al (2019)

Obese Individuals with and without Type 2 Diabetes Show Different Gut Microbial Functional Capacity and Composition.

Cell host & microbe pii:S1931-3128(19)30348-8 [Epub ahead of print].

Obesity and type 2 diabetes (T2D) are metabolic disorders that are linked to microbiome alterations. However, their co-occurrence poses challenges in disentangling microbial features unique to each condition. We analyzed gut microbiomes of lean non-diabetic (n = 633), obese non-diabetic (n = 494), and obese individuals with T2D (n = 153) from German population and metabolic disease cohorts. Microbial taxonomic and functional profiles were analyzed along with medical histories, serum metabolomics, biometrics, and dietary data. Obesity was associated with alterations in microbiome composition, individual taxa, and functions with notable changes in Akkermansia, Faecalibacterium, Oscillibacter, and Alistipes, as well as in serum metabolites that correlated with gut microbial patterns. However, microbiome associations were modest for T2D, with nominal increases in Escherichia/Shigella. Medications, including antihypertensives and antidiabetics, along with dietary supplements including iron, were significantly associated with microbiome variation. These results differentiate microbial components of these interrelated metabolic diseases and identify dietary and medication exposures to consider in future studies.

RevDate: 2019-08-10

Jiang P, Green SJ, Chlipala GE, et al (2019)

Reproducible changes in the gut microbiome suggest a shift in microbial and host metabolism during spaceflight.

Microbiome, 7(1):113 pii:10.1186/s40168-019-0724-4.

BACKGROUND: Space environment imposes a range of challenges to mammalian physiology and the gut microbiota, and interactions between the two are thought to be important in mammalian health in space. While previous findings have demonstrated a change in the gut microbial community structure during spaceflight, specific environmental factors that alter the gut microbiome and the functional relevance of the microbiome changes during spaceflight remain elusive.

METHODS: We profiled the microbiome using 16S rRNA gene amplicon sequencing in fecal samples collected from mice after a 37-day spaceflight onboard the International Space Station. We developed an analytical tool, named STARMAPs (Similarity Test for Accordant and Reproducible Microbiome Abundance Patterns), to compare microbiome changes reported here to other relevant datasets. We also integrated the gut microbiome data with the publically available transcriptomic data in the liver of the same animals for a systems-level analysis.

RESULTS: We report an elevated microbiome alpha diversity and an altered microbial community structure that were associated with spaceflight environment. Using STARMAPs, we found the observed microbiome changes shared similarity with data reported in mice flown in a previous space shuttle mission, suggesting reproducibility of the effects of spaceflight on the gut microbiome. However, such changes were not comparable with those induced by space-type radiation in Earth-based studies. We found spaceflight led to significantly altered taxon abundance in one order, one family, five genera, and six species of microbes. This was accompanied by a change in the inferred microbial gene abundance that suggests an altered capacity in energy metabolism. Finally, we identified host genes whose expression in the liver were concordantly altered with the inferred gut microbial gene content, particularly highlighting a relationship between host genes involved in protein metabolism and microbial genes involved in putrescine degradation.

CONCLUSIONS: These observations shed light on the specific environmental factors that contributed to a robust effect on the gut microbiome during spaceflight with important implications for mammalian metabolism. Our findings represent a key step toward a better understanding the role of the gut microbiome in mammalian health during spaceflight and provide a basis for future efforts to develop microbiota-based countermeasures that mitigate risks to crew health during long-term human space expeditions.


RJR Experience and Expertise


Robbins holds BS, MS, and PhD degrees in the life sciences. He served as a tenured faculty member in the Zoology and Biological Science departments at Michigan State University. He is currently exploring the intersection between genomics, microbial ecology, and biodiversity — an area that promises to transform our understanding of the biosphere.


Robbins has extensive experience in college-level education: At MSU he taught introductory biology, genetics, and population genetics. At JHU, he was an instructor for a special course on biological database design. At FHCRC, he team-taught a graduate-level course on the history of genetics. At Bellevue College he taught medical informatics.


Robbins has been involved in science administration at both the federal and the institutional levels. At NSF he was a program officer for database activities in the life sciences, at DOE he was a program officer for information infrastructure in the human genome project. At the Fred Hutchinson Cancer Research Center, he served as a vice president for fifteen years.


Robbins has been involved with information technology since writing his first Fortran program as a college student. At NSF he was the first program officer for database activities in the life sciences. At JHU he held an appointment in the CS department and served as director of the informatics core for the Genome Data Base. At the FHCRC he was VP for Information Technology.


While still at Michigan State, Robbins started his first publishing venture, founding a small company that addressed the short-run publishing needs of instructors in very large undergraduate classes. For more than 20 years, Robbins has been operating The Electronic Scholarly Publishing Project, a web site dedicated to the digital publishing of critical works in science, especially classical genetics.


Robbins is well-known for his speaking abilities and is often called upon to provide keynote or plenary addresses at international meetings. For example, in July, 2012, he gave a well-received keynote address at the Global Biodiversity Informatics Congress, sponsored by GBIF and held in Copenhagen. The slides from that talk can be seen HERE.


Robbins is a skilled meeting facilitator. He prefers a participatory approach, with part of the meeting involving dynamic breakout groups, created by the participants in real time: (1) individuals propose breakout groups; (2) everyone signs up for one (or more) groups; (3) the groups with the most interested parties then meet, with reports from each group presented and discussed in a subsequent plenary session.


Robbins has been engaged with photography and design since the 1960s, when he worked for a professional photography laboratory. He now prefers digital photography and tools for their precision and reproducibility. He designed his first web site more than 20 years ago and he personally designed and implemented this web site. He engages in graphic design as a hobby.

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E-mail: RJR8222@gmail.com

Collection of publications by R J Robbins

Reprints and preprints of publications, slide presentations, instructional materials, and data compilations written or prepared by Robert Robbins. Most papers deal with computational biology, genome informatics, using information technology to support biomedical research, and related matters.

Research Gate page for R J Robbins

ResearchGate is a social networking site for scientists and researchers to share papers, ask and answer questions, and find collaborators. According to a study by Nature and an article in Times Higher Education , it is the largest academic social network in terms of active users.

Curriculum Vitae for R J Robbins

short personal version

Curriculum Vitae for R J Robbins

long standard version

RJR Picks from Around the Web (updated 11 MAY 2018 )