@article {pmid39366290,
year = {2024},
author = {Bundurus, IA and Balta, I and Pet, I and Stef, L and Popescu, CA and McCleery, D and Lemon, J and Callaway, T and Douglas, A and Corcionivoschi, N},
title = {Mechanistic concepts involved in biofilm associated processes of Campylobacter jejuni: persistence and inhibition in poultry environments.},
journal = {Poultry science},
volume = {103},
number = {12},
pages = {104328},
doi = {10.1016/j.psj.2024.104328},
pmid = {39366290},
issn = {1525-3171},
abstract = {Campylobacter species, predominantly Campylobacter jejuni, remains a significant zoonotic pathogen worldwide, with the poultry sector being the primary vector for human transmission. In recent years. there has been a notable rise in the incidence of human campylobacteriosis, necessitating a deeper understanding of the pathogen's survival mechanisms and transmission dynamics. Biofilm presence significantly contributes to C. jejuni persistence in poultry and subsequent food product contamination, and this review describes the intricate processes involved in biofilm formation. The ability of Campylobacter to form biofilms on various surfaces, including stainless steel, plastic, and glass, is a critical survival strategy. Campylobacter biofilms, with their remarkable resilience, protect the pathogen from environmental stresses such as desiccation, pH extremes, biocides and sanitizing agents. This review explores the molecular and genetic mechanisms of C. jejuni biofilm formation, highlighting regulatory genes involved in motility, chemotaxis, and stress responses. Flagellar proteins, particularly flaA, flaB, flaG, and adhesins like cadF and flpA, are identified as the main molecular components in biofilm development. The role of mixed-species biofilms, where C. jejuni integrates into existing biofilms of other bacteria to enhance pathogen resilience, is also discussed. This review also considers alternative interventions to control C. jejuni in poultry production, in the context of increasing antibiotic resistance. It explores the effectiveness of prebiotics, probiotics, synbiotics, bacteriocins, bacteriophages, vaccines, and organic acids, with a focus on their mechanisms of action in reducing bacterial colonization and biofilm formation. Studies show that mixtures of organic acids and compounds like Carvacrol and Eugenol significantly downregulate genes linked with motility and adhesion, thereby disrupting biofilm integrity. It discusses the impact of environmental factors, such as temperature and oxygen levels on biofilm formation, providing insights into how industrial conditions can be manipulated to reduce contamination. This paper stresses the need for a multifaceted approach to control Campylobacter in poultry, integrating molecular and genetic insights with practical interventions. By advancing our understanding of biofilm dynamics and gene regulation, we aim to inform the development of more effective strategies to enhance food safety and protect public health.},
}

@article {pmid39367219,
year = {2024},
author = {Battulga, B and Nakanishi, T and Atarashi-Andoh, M and Otosaka, S and Koarashi, J},
title = {Biofilm-mediated interactions between plastics and radiocesium in coastal environments.},
journal = {Environmental science and pollution research international},
volume = {},
number = {},
pages = {},
pmid = {39367219},
issn = {1614-7499},
support = {23KK0201//Japan Society for the Promotion of Science/ ; },
abstract = {A ubiquitous distribution of plastic debris has been reported in aquatic and terrestrial environments; however, the interactions between plastics and radionuclides and the radioactivity of environmental plastics remain largely unknown. Here, we characterize biofilms developing on the surface of plastic debris to explore the role of plastic-associated biofilms as an interaction medium between plastics and radiocesium ([137]Cs) in the environment. Biofilm samples were extracted from plastics (1-50 mm in size) collected from two contrasting coastal areas in Japan. The radioactivity of plastics was estimated based on the [137]Cs activity concentration of the biofilms and compared seasonally with surrounding environmental samples (i.e., sediment and sand). [137]Cs traces were detected in biofilms with activity concentrations of 21-1300 Bq·kg[-1] biofilm (dry weight), corresponding to 0.04-4.5 Bq·kg[-1] plastic (dry weight). Our results reveal the interaction between [137]Cs and plastics and provide evidence that organic and mineral components in biofilms are essential in [137]Cs retention in environmental plastics. Given the ubiquitous distribution of plastic debris in the environment, more attention should be directed to bioaccumulation and the radioecological impacts of plastic-associated radionuclides on ecosystems.},
}

@article {pmid39366990,
year = {2024},
author = {Pappe, E and Hübner, RH and Saccomanno, J and Ebrahimi, HDN and Witzenrath, M and Wiessner, A and Sarbandi, K and Xiong, Z and Kursawe, L and Moter, A and Kikhney, J},
title = {Biofilm infections of endobronchial valves in COPD patients after endoscopic lung volume reduction: a pilot study with FISHseq.},
journal = {Scientific reports},
volume = {14},
number = {1},
pages = {23078},
pmid = {39366990},
issn = {2045-2322},
mesh = {Humans ; *Biofilms/growth & development ; Pilot Projects ; Male ; *Pulmonary Disease, Chronic Obstructive/microbiology ; Female ; Aged ; *In Situ Hybridization, Fluorescence ; Middle Aged ; Pneumonectomy/methods ; },
abstract = {Endoscopic lung volume reduction (ELVR) using endobronchial valves (EBV) is a treatment option for a subset of patients with severe chronic obstructive pulmonary disease (COPD), suffering from emphysema and hyperinflation. In this pilot study, we aimed to determine the presence of bacterial biofilm infections on EBV and investigate their involvement in lack of clinical benefits, worsening symptomatology, and increased exacerbations that lead to the decision to remove EBVs. We analyzed ten COPD patients with ELVR who underwent EBV removal. Clinical data were compared to the microbiological findings from conventional EBV culture. In addition, EBV were analyzed by FISHseq, a combination of Fluorescence in situ hybridization (FISH) with PCR and sequencing, for visualization and identification of microorganisms and biofilms. All ten patients presented with clinical symptoms, including pneumonia and recurrent exacerbations. Microbiological cultures from EBV detected several microorganisms in all ten patients. FISHseq showed either mixed or monospecies colonization on the EBV, including oropharyngeal bacterial flora, Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcus spp., and Fusobacterium sp. On 5/10 EBV, FISHseq visualized biofilms, on 1/10 microbial microcolonies, on 3/10 single microorganisms, and on 1/10 no microorganisms. The results of the study demonstrate the presence of biofilms on EBV for the first time and its potential involvement in increased exacerbations and clinical worsening in patients with ELVR. However, further prospective studies are needed to evaluate the clinical relevance of biofilm formation on EBV and appropriate treatment options to avoid infections in patients with ELVR.},
}

Humans
*Biofilms/growth & development
Pilot Projects
Male
*Pulmonary Disease, Chronic Obstructive/microbiology
Female
Aged
*In Situ Hybridization, Fluorescence
Middle Aged
Pneumonectomy/methods

@article {pmid39363349,
year = {2024},
author = {Ivers, C and Kaya, EC and Yucel, U and Boyle, D and Trinetta, V},
title = {Evaluation of Salmonella biofilm attachment and hydrophobicity characteristics on food contact surfaces.},
journal = {BMC microbiology},
volume = {24},
number = {1},
pages = {387},
pmid = {39363349},
issn = {1471-2180},
mesh = {*Biofilms/growth & development ; *Hydrophobic and Hydrophilic Interactions ; *Salmonella/physiology/growth & development ; *Bacterial Adhesion ; *Food Microbiology ; Surface Properties ; Microscopy, Confocal ; Food Contamination ; },
abstract = {Salmonella forms biofilms, and persist on food contact surfaces. Once a biofilm is formed cleaning and sanitation protocols may be inadequate for effective removal. This study evaluated attachment characteristics, surface properties, and structure of Salmonella biofilms on food contact surfaces commonly used in the tree-fruit industry. Multi-strain Salmonella biofilms were grown in a Centers for Disease Control and Prevention (CDC) biofilm reactor at 22 ± 2 °C and sampling was conducted at 2, 24 and 96-h. After each incubation period, coupons weregently rinsed and the remaining cells enumerated. Biofilms were analyzed with Laser Scanning Confocal Microscopy (LSCM). Hydrophobicity was evaluated by measuring the contact angles of reference liquids method using a drop tensiometer instrument. Material type and biofilm age significantly influenced attachment and biofilm hydrophobicity (P < 0.05). The strength of attachment, across all time points, was highest on nylon followed by wood and high-density polyethylene. The highest contact angle measurements were observed after 96-h of biofilm formation for each material. All the results and observations from this study contribute to a better understanding of the attachment and hydrophobicity characteristics of Salmonella and might help producers make informed decisions when selecting containers for harvesting and storing in order to minimize biofilm formation and potential for cross-contamination.},
}

*Biofilms/growth & development
*Hydrophobic and Hydrophilic Interactions
*Salmonella/physiology/growth & development
*Bacterial Adhesion
*Food Microbiology
Surface Properties
Microscopy, Confocal
Food Contamination

@article {pmid39363239,
year = {2024},
author = {Vatankhah, M and Mahboubi, A and Varshochian, R and Haeri, A and Houri, H and Abbasian, Z and Dadashzadeh, S},
title = {Thermosensitive multivesicular liposomal hydrogel: a potential platform for loco-regional drug delivery in the treatment of osteomyelitis caused by antibiotic-resistant biofilm-forming bacteria.},
journal = {Letters in applied microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1093/lambio/ovae092},
pmid = {39363239},
issn = {1472-765X},
abstract = {Biofilm-mediated osteomyelitis presents significant therapeutic challenges. Given the limitations of existing osteomyelitis treatment approaches, there is a distinct need to develop a localized drug delivery system that is biocompatible, biodegradable, and capable of controlled antibiotic release. Multivesicular liposomes (MVLs), characterized by their non-concentric vesicular structure, distinct composition, and enhanced stability, serve as the system for a robust sustained-release drug delivery platform. In this study, various hydrogel formulations composed of poloxamer 407 and other hydrogels, incorporating vancomycin hydrochloride (VAN HL) -loaded MVLs (VAN HL-MVL), were prepared and evaluated. The optimized VAN HL-MVL sol-gel system, consisting of poloxamer 407 and hyaluronic acid, successfully maintained drug release for up to three weeks and exhibited shear-thinning behavior at 37°C. While complete drug release from MVLs alone took place in 312 hours, the hydrogel formulation extended this release to 504 hours. The released drug effectively inhibited the Staphylococcus aureus biofilms growth within 24 hours and methicillin-resistant Staphylococcus aureus biofilms within 72 hours. It also eradicated pre-formed biofilms of Staphylococcus aureus and methicillin-resistant Staphylococcus aureus in 96 and 120 hours, respectively. This injectable in situ gel system incorporating VAN HL-MVLs holds potential as an alternative to undergoing multiple surgeries for osteomyelitis treatment and warrants further studies.},
}

@article {pmid39362854,
year = {2024},
author = {Kunisch, F and Campobasso, C and Wagemans, J and Yildirim, S and Chan, BK and Schaudinn, C and Lavigne, R and Turner, PE and Raschke, MJ and Trampuz, A and Gonzalez Moreno, M},
title = {Targeting Pseudomonas aeruginosa biofilm with an evolutionary trained bacteriophage cocktail exploiting phage resistance trade-offs.},
journal = {Nature communications},
volume = {15},
number = {1},
pages = {8572},
pmid = {39362854},
issn = {2041-1723},
support = {01KI1823//Bundesministerium für Bildung und Forschung (Federal Ministry of Education and Research)/ ; },
mesh = {*Pseudomonas aeruginosa/virology/physiology/drug effects ; *Biofilms/growth & development ; *Bacteriophages/physiology/genetics ; *Anti-Bacterial Agents/pharmacology ; Pseudomonas Phages/physiology/genetics ; Humans ; Phage Therapy/methods ; Drug Resistance, Multiple, Bacterial ; Pseudomonas Infections/therapy/microbiology ; Host Specificity ; Microbial Sensitivity Tests ; },
abstract = {Spread of multidrug-resistant Pseudomonas aeruginosa strains threatens to render currently available antibiotics obsolete, with limited prospects for the development of new antibiotics. Lytic bacteriophages, the viruses of bacteria, represent a path to combat this threat. In vitro-directed evolution is traditionally applied to expand the bacteriophage host range or increase bacterial suppression in planktonic cultures. However, while up to 80% of human microbial infections are biofilm-associated, research towards targeted improvement of bacteriophages' ability to combat biofilms remains scarce. This study aims at an in vitro biofilm evolution assay to improve multiple bacteriophage parameters in parallel and the optimisation of bacteriophage cocktail design by exploiting a bacterial bacteriophage resistance trade-off. The evolved bacteriophages show an expanded host spectrum, improved antimicrobial efficacy and enhanced antibiofilm performance, as assessed by isothermal microcalorimetry and quantitative polymerase chain reaction, respectively. Our two-phage cocktail reveals further improved antimicrobial efficacy without incurring dual-bacteriophage-resistance in treated bacteria. We anticipate this assay will allow a better understanding of phenotypic-genomic relationships in bacteriophages and enable the training of bacteriophages against other desired pathogens. This, in turn, will strengthen bacteriophage therapy as a treatment adjunct to improve clinical outcomes of multidrug-resistant bacterial infections.},
}

*Pseudomonas aeruginosa/virology/physiology/drug effects
*Biofilms/growth & development
*Bacteriophages/physiology/genetics
*Anti-Bacterial Agents/pharmacology
Pseudomonas Phages/physiology/genetics
Humans
Phage Therapy/methods
Drug Resistance, Multiple, Bacterial
Pseudomonas Infections/therapy/microbiology
Host Specificity
Microbial Sensitivity Tests

@article {pmid39362422,
year = {2024},
author = {Bellich, B and Cacioppo, M and De Zorzi, R and Rizzo, R and Brady, JW and Cescutti, P},
title = {Interactions of biofilm polysaccharides produced by human infective bacteria with molecules of the quorum sensing system. A microscopy and NMR study.},
journal = {International journal of biological macromolecules},
volume = {},
number = {},
pages = {136222},
doi = {10.1016/j.ijbiomac.2024.136222},
pmid = {39362422},
issn = {1879-0003},
abstract = {Biofilms are the most common lifestyle adopted by bacterial communities where cells live embedded in a self-produced hydrated matrix. Although polysaccharides are considered essential for matrix architecture, their possible functional roles are still rather unexplored. The primary structure of polysaccharides produced by Klebsiella pneumoniae and species of the Burkholderia cepacia Complex revealed a composition rich in rhamnose. The methyl group on carbon 6 of rhamnose units lowers the polymer hydrophilicity and can form low polarity regions on the polysaccharide chains. These regions promote chain-chain interactions that contribute to the biofilm matrix stability, but may also act as binding sites for low-polarity molecules, aiding their mobility through the hydrated matrix. In particular, quorum sensing system components crucial for the biofilm life cycle often display poor solubility in water. Therefore, cis-11-methyl-2-dodecenoic acid and L-homoserine-lactones were investigated by NMR spectroscopy for their possible interaction with polysaccharides. In addition, the macromolecular morphology of the polysaccharides was assessed using atomic force and electron microscopies to define the role of Rha residues on the three-dimensional conformation of the polymer. NMR data revealed that quorum sensing components interact with Rhamnose-rich polysaccharides, and the extent of interaction depends on the specific primary structure of each polysaccharide.},
}

@article {pmid39361981,
year = {2024},
author = {Zhou, J and Ramasamy, P and Li, K},
title = {Corrigendum to "Chitosan-collagen biopolymer biofilm derived from cephalopod gladius; evaluation of osteogenesis, angiogenesis and wound healing for tissue engineering application" [Int. J. Biol. Macromol. 2024 Aug 26;279(Pt 1):135078].},
journal = {International journal of biological macromolecules},
volume = {281},
number = {Pt 1},
pages = {136104},
doi = {10.1016/j.ijbiomac.2024.136104},
pmid = {39361981},
issn = {1879-0003},
}

@article {pmid39361487,
year = {2024},
author = {Tahir, S and Parvin, F and Wang, M and Deva, AK and Vickery, K and Hu, H},
title = {The efficacy of antimicrobial solutions against multispecies bacterial biofilm with or without negative pressure wound therapy in an in vitro wound model.},
journal = {The Journal of antimicrobial chemotherapy},
volume = {},
number = {},
pages = {},
doi = {10.1093/jac/dkae338},
pmid = {39361487},
issn = {1460-2091},
support = {//KCI Medical Australia Pty Ltd/ ; },
abstract = {OBJECTIVES: Biofilm is the major challenge in chronic wound management. Instilling a wound cleansing solution aids in wound bed cleaning and infectious pathogen elimination. Negative pressure wound therapy (NPWT) improves the wound-healing process. This study investigated the efficacy of two antimicrobials (Vashe Wound Cleanser and Prontosan Wound Irrigation Solution) against a multispecies bacterial biofilm with or without NPWT in an in vitro wound model.

METHODS: A mixed multispecies biofilm containing Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcus pyogenes, and Acinetobacter baumannii was developed and verified by scanning electron microscopy and fluorescent in situ hybridization. The efficacy of Vashe and Prontosan against multispecies biofilm with or without NPWT was evaluated by colony-forming unit (cfu) of each species and total bacterial number, and visually confirmed by live/dead stain and confocal microscopy.

RESULTS: Prontosan reduced biofilm cell numbers significantly: 6 instils over 24 h resulting in 3.86 ± 0.14 cfu log10 reduction without NPWT and 4.75 ± 0.13 cfu log10 reduction combined with NPWT (P < 0.01) and 12 instils over 48 h resulting in 5.24 ± 0.11 cfu log10 reduction without NPWT and biofilm eradication with NPWT (P < 0.001). NPWT alone or combined with Vashe failed to reduce multispecies biofilm numbers significantly over 24 or 48 h.

CONCLUSIONS: Prontosan significantly reduced biofilm cell numbers, with better efficacy over 48 than 24 h, emphasizing the necessity for persistent and robust treatment. NPWT enhanced the effectiveness of Prontosan instillation. However, NPWT alone or combined with Vashe showed limited efficacy and difficulty when combating the multispecies biofilm in vitro.},
}

@article {pmid39361085,
year = {2024},
author = {Hindieh, P and Yaghi, J and Assaf, JC and Chokr, A and Atoui, A and Louka, N and Khoury, AE},
title = {Unlocking the potential of lactic acid bacteria mature biofilm extracts as antibiofilm agents.},
journal = {AMB Express},
volume = {14},
number = {1},
pages = {112},
pmid = {39361085},
issn = {2191-0855},
abstract = {The continuous growth of biofilm infections and their resilience to conventional cleaning methods and antimicrobial agents pose a worldwide challenge across diverse sectors. This persistent medical, industrial, and environmental issue contributes to treatment challenges and chronic diseases. Lactic acid bacteria have garnered global attention for their substantial antimicrobial effects against pathogens and established beneficial roles. Notably, their biofilms are also predicted to show a promising control strategy against pathogenic biofilm formation. The prevalence of biofilm-related problems underscores the need for extensive research and innovative solutions to tackle this global challenge. This novel study investigates the effect of different extracts (external, internal, and mixed extracts) obtained from Lactobacillus rhamnosus GG biofilm on pathogenic-formed biofilms. Subsequently, external extracts presented an important eradication effectiveness. Furthermore, a 6-fold concentration of these extracts led to eradication percentages of 57%, 67%, and 76% for Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa biofilms, respectively, and around 99.9% bactericidal effect of biofilm cells was observed for the three strains. The results of this research could mark a significant breakthrough in the field of anti-biofilm and antimicrobial strategies. Further studies and molecular research will be necessary to detect the molecules secreted by the biofilm, and their mechanisms of action engaged in new anti-biofilm strategies.},
}

@article {pmid39360839,
year = {2024},
author = {Gómez-Mejia, A and Orlietti, M and Tarnutzer, A and Mairpady Shambat, S and Zinkernagel, AS},
title = {Inhibition of Streptococcus pyogenes biofilm by Lactiplantibacillus plantarum and Lacticaseibacillus rhamnosus.},
journal = {mSphere},
volume = {},
number = {},
pages = {e0043024},
doi = {10.1128/msphere.00430-24},
pmid = {39360839},
issn = {2379-5042},
abstract = {The human pathobiont Streptococcus pyogenes forms biofilms and causes infections, such as pharyngotonsillitis and necrotizing fasciitis. Bacterial biofilms are more resilient to antibiotic treatment, and new therapeutic strategies are needed to control biofilm-associated infections, such as recurrent pharyngotonsillitis. Lactiplantibacillus plantarum and Lacticaseibacillus rhamnosus are two bacterial commensals used for their probiotic properties. This study aimed to elucidate the anti-biofilm properties of L. plantarum and L. rhamnosus cell-free supernatants (LPSN and LRSN, respectively) on S. pyogenes biofilms grown in vitro in supplemented minimal medium. When planktonic or biofilm S. pyogenes were exposed to LPSN or LRSN, S. pyogenes survival was reduced significantly in a concentration-dependent manner, and the effect was more pronounced on preformed biofilms. Enzymatic digestion of LPSN and LRSN suggested that glycolipid compounds might cause the antimicrobial effect. In conclusion, this study indicates that L. plantarum and L. rhamnosus produce glycolipid bioactive compounds that reduce the viability of S. pyogenes in planktonic and biofilm cultures.IMPORTANCEStreptococcus pyogenes infections are a significant concern for populations at risk, such as children and the elderly, as non-invasive conditions such as impetigo and strep throat can lead to severe invasive diseases such as necrotizing fasciitis. Despite its susceptibility to current antibiotics, the formation of biofilm by this pathogen decreases the efficacy of antibiotic treatment alone. The ability of commensal lactobacillus to kill S. pyogenes has been documented by previous studies using in vitro settings. The relevance of our study is in using a physiological setup and a more detailed understanding of the nature of the lactobacillus molecule affecting the viability of S. pyogenes. This additional knowledge will help for a better comprehension of the molecules' characteristics and kinetics, which in turn will facilitate new avenues of research for its translation to new therapies.},
}

@article {pmid39360709,
year = {2024},
author = {Hu, R and Qian, H and Wang, X and Peng, B and Huang, D},
title = {Nicotine promotes pathogenic bacterial growth and biofilm formation in peri-implant.},
journal = {Journal of medical microbiology},
volume = {73},
number = {10},
pages = {},
doi = {10.1099/jmm.0.001897},
pmid = {39360709},
issn = {1473-5644},
mesh = {*Biofilms/drug effects/growth & development ; *Nicotine/pharmacology ; Humans ; *Peri-Implantitis/microbiology ; Fusobacterium nucleatum/drug effects/growth & development/physiology ; Porphyromonas gingivalis/drug effects/growth & development ; Male ; Dental Implants/microbiology ; Female ; Interleukin-6/metabolism ; Middle Aged ; Interleukins/metabolism ; Streptococcus sanguis/drug effects/growth & development ; Bacteria/drug effects/classification/genetics/growth & development/isolation & purification ; Smoking/adverse effects ; },
abstract = {Introduction. Peri-implantitis is a plaque-associated disease that leads to implant loss and arises from bacterial biofilms on the surface of the implant. Smoking is a risk factor for peri-implantitis and impedes treatment effectiveness. Additionally, aryl hydrocarbon receptor (AHR), IL-6, and IL-22 levels are related to peri-implantitis.Aim. We aimed to investigate the effects of nicotine on inflammatory response, bacterial growth and biofilm formation.Hypothesis/Gap Statement. We hypothesized that nicotine promoted pathogenic bacterial growth and biofilm formation, thereby aggravating inflammation.Methodology. The expression of AHR, IL-6 and IL-22 was measured in peri-implant sulci fluid using quantitative PCR and Western blot analyses. The cementum was incubated with bacterial suspension including Porphyromonas gingivalis, Streptococcus sanguinis and Fusobacterium nucleatum and treated with 100, 200, 250 and 300 µg ml[-1] nicotine, and then, the absorbance and number of colony-forming units were detected. Biofilm formation was evaluated using the tissue culture plate method and safranin O staining. Carbohydrates and proteins were measured by the phenol-sulfuric acid method and the bicinchoninic acid method, respectively.Results. The results indicated that smoking increased the levels of AHR, IL-6 and IL-22. Functionally, nicotine promoted the growth of P. gingivalis, S. sanguinis and F. nucleatum. Additionally, it promoted the biofilm formation of these bacteria and increased the contents of carbohydrates and proteins.Conclusion. Nicotine promoted bacterial growth and biofilm build-up, suggesting that smoking may aggravate the progression of peri-implantitis.},
}

*Biofilms/drug effects/growth & development
*Nicotine/pharmacology
Humans
*Peri-Implantitis/microbiology
Fusobacterium nucleatum/drug effects/growth & development/physiology
Porphyromonas gingivalis/drug effects/growth & development
Male
Dental Implants/microbiology
Female
Interleukin-6/metabolism
Middle Aged
Interleukins/metabolism
Streptococcus sanguis/drug effects/growth & development
Bacteria/drug effects/classification/genetics/growth & development/isolation & purification
Smoking/adverse effects

@article {pmid39359676,
year = {2024},
author = {Wang, J and Yang, J and Durairaj, P and Wang, W and Wei, D and Tang, S and Liu, H and Wang, D and Jia, AQ},
title = {Discovery of β-nitrostyrene derivatives as potential quorum sensing inhibitors for biofilm inhibition and antivirulence factor therapeutics against Serratia marcescens.},
journal = {mLife},
volume = {3},
number = {3},
pages = {445-458},
pmid = {39359676},
issn = {2770-100X},
abstract = {Quorum sensing (QS) inhibition has emerged as a promising target for directed drug design, providing an appealing strategy for developing antimicrobials, particularly against infections caused by drug-resistant pathogens. In this study, we designed and synthesized a total of 33 β-nitrostyrene derivatives using 1-nitro-2-phenylethane (NPe) as the lead compound, to target the facultative anaerobic bacterial pathogen Serratia marcescens. The QS-inhibitory effects of these compounds were evaluated using S. marcescens NJ01 and the reporter strain Chromobacterium violaceum CV026. Among the 33 new β-nitrostyrene derivatives, (E)-1-methyl-4-(2-nitrovinyl)benzene (m-NPe, compound 28) was proven to be a potent inhibitor that reduced biofilm formation of S. marcescens NJ01 by 79%. Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) results revealed that treatment with m-NPe (50 μg/ml) not only enhanced the susceptibility of the formed biofilms but also disrupted the architecture of biofilms by 84%. m-NPe (50 μg/ml) decreased virulence factors in S. marcescens NJ01, reducing the activity of protease, prodigiosin, and extracellular polysaccharide (EPS) by 36%, 72%, and 52%, respectively. In S. marcescens 4547, the activities of hemolysin and EPS were reduced by 28% and 40%, respectively, outperforming the positive control, vanillic acid (VAN). The study also found that the expression levels of QS- and biofilm-related genes (flhD, fimA, fimC, sodB, bsmB, pigA, pigC, and shlA) were downregulated by 1.21- to 2.32-fold. Molecular dynamics analysis showed that m-NPe could bind stably to SmaR, RhlI, RhlR, LasR, and CviR proteins in a 0.1 M sodium chloride solution. Importantly, a microscale thermophoresis (MST) test revealed that SmaR could be a target protein for the screening of a quorum sensing inhibitor (QSI) against S. marcescens. Overall, this study highlights the efficacy of m-NPe in suppressing the virulence factors of S. marcescens, identifying it as a new potential QSI and antibiofilm agent capable of restoring or improving antimicrobial drug sensitivity.},
}

@article {pmid39358894,
year = {2024},
author = {Gao, Y and Wang, J and Deng, Z and Wang, Y and Zhang, D and Xu, X and Yu, X and Wei, X},
title = {Targeted Delivery of 2D Composite Minerals for Biofilm Removal.},
journal = {ACS applied materials & interfaces},
volume = {16},
number = {39},
pages = {52814-52823},
doi = {10.1021/acsami.4c10998},
pmid = {39358894},
issn = {1944-8252},
mesh = {*Biofilms/drug effects ; *Staphylococcus aureus/drug effects ; *Escherichia coli/drug effects ; Anti-Bacterial Agents/pharmacology/chemistry ; Chlorhexidine/pharmacology/chemistry ; Corrosion ; Magnetite Nanoparticles/chemistry ; Microbial Sensitivity Tests ; },
abstract = {Microbiologically influenced corrosion (MIC) poses considerable challenges in various industries, prompting the exploration of advanced materials to mitigate microbial threats. This study successfully synthesized nanoscale vermiculite (VMT) from natural seawater and utilized it as a foundation to integrate magnetic nanoparticles (Fe3O4) and chlorhexidine acetate (CA) for inhibiting MIC. A comprehensive investigation encompassing the synthesis, characterization, and application of these VMT/Fe3O4/CA composites was conducted to evaluate their antimicrobial effectiveness against Escherichia coli, Staphylococcus aureus, and sulfate-reducing bacteria (SRB), demonstrating an efficacy exceeding 99.5%. Moreover, the composite material demonstrated the capability to align with a magnetic field, enabling precise drug targeting and release, thereby facilitating biofilm removal. This research makes a significant contribution to the advancement of intelligent, efficient, and eco-friendly corrosion protection solutions.},
}

*Biofilms/drug effects
*Staphylococcus aureus/drug effects
*Escherichia coli/drug effects
Anti-Bacterial Agents/pharmacology/chemistry
Chlorhexidine/pharmacology/chemistry
Corrosion
Magnetite Nanoparticles/chemistry
Microbial Sensitivity Tests

@article {pmid39358363,
year = {2024},
author = {Valiei, A and Dickson, A and Aminian-Dehkordi, J and Mofrad, MRK},
title = {Metabolic interactions shape emergent biofilm structures in a conceptual model of gut mucosal bacterial communities.},
journal = {NPJ biofilms and microbiomes},
volume = {10},
number = {1},
pages = {99},
pmid = {39358363},
issn = {2055-5008},
mesh = {*Gastrointestinal Microbiome ; *Biofilms/growth & development ; Humans ; *Bacteria/classification/metabolism/genetics ; *Microbial Interactions ; Computer Simulation ; Symbiosis ; Models, Biological ; Bacterial Physiological Phenomena ; Intestinal Mucosa/microbiology/metabolism ; },
abstract = {The gut microbiome plays a major role in human health; however, little is known about the structural arrangement of microbes and factors governing their distribution. In this work, we present an in silico agent-based model (ABM) to conceptually simulate the dynamics of gut mucosal bacterial communities. We explored how various types of metabolic interactions, including competition, neutralism, commensalism, and mutualism, affect community structure, through nutrient consumption and metabolite exchange. Results showed that, across scenarios with different initial species abundances, cross-feeding promotes species coexistence. Morphologically, competition and neutralism resulted in segregation, while mutualism and commensalism fostered high intermixing. In addition, cooperative relations resulted in community properties with little sensitivity to the selective uptake of metabolites produced by the host. Moreover, metabolic interactions strongly influenced colonization success following the invasion of newcomer species. These results provide important insights into the utility of ABM in deciphering complex microbiome patterns.},
}

*Gastrointestinal Microbiome
*Biofilms/growth & development
Humans
*Bacteria/classification/metabolism/genetics
*Microbial Interactions
Computer Simulation
Symbiosis
Models, Biological
Bacterial Physiological Phenomena
Intestinal Mucosa/microbiology/metabolism

@article {pmid39353484,
year = {2024},
author = {Yu, G and Huang, TY and Li, Y},
title = {Kanamycin promotes biofilm viability of MRSA strains showing extremely high resistance to kanamycin.},
journal = {Microbial pathogenesis},
volume = {},
number = {},
pages = {106986},
doi = {10.1016/j.micpath.2024.106986},
pmid = {39353484},
issn = {1096-1208},
abstract = {Staphylococcus aureus is widely distributed in environment and can cause various human infection and food poisoning cases. Also, this pathogen is a typical biofilm former, which further complicates its pathogenicity. Antibiotics have been widely used to eliminate pathogenic bacteria, but their indiscriminate use has also led to the widespread emergence of drug-resistant bacteria, such as Methicillin-Resistant Staphylococcus aureus (MRSA). In this study, the effect of antibiotics on biofilm formation of MRSA strains 875 and 184 was explored. Firstly, MRSA 875 belongs to SCCmec type IV, ST239, carrying the atl, icaA, icaD, icaBC, and aap genes, and MRSA 184 belongs to SCCmec type II, ST5, carrying the atl, icaD, icaBC, aap, and agr genes. Then, a total of 8 antibiotics have been selected, including kanamycin, gentamycin, cipprofloxacin, erythromycin, meropenem, penicillin G, tetracycline, vancomycin. Minimum inhibitory concentrations (MICs) of each antibiotic were determined, and MIC of MRSA 875 and 184 to kanamycin/gentamicin are 2048/64 μg/mL and 2048/4 μg/mL, respectively. A total of 10 concentrations, ranging from 1/128 to 4 MIC with 2-fold, were used to study biofilm formation. Biofilm biomass and viability were determined during different phases, including initial adhesion (8 h), proliferation (16 h), accumulation (24 h) and maturation (48 h). Importantly, kanamycin at specific concentrations showed significant promotion of biofilm biomass and biofilm viability, with none of such observation acquired from other antibiotics. This study provides scientific basis and new research ideas for the quality control technology of microorganisms and safety prevention of MRSA.},
}

@article {pmid39353242,
year = {2024},
author = {Ahmad, A and Al Senaidi, AS and Mubarak, MS},
title = {Microbial approach towards anode biofilm engineering enhances extracellular electron transfer for bioenergy production.},
journal = {Journal of environmental management},
volume = {370},
number = {},
pages = {122696},
doi = {10.1016/j.jenvman.2024.122696},
pmid = {39353242},
issn = {1095-8630},
abstract = {Applying microbial electrolysis cells (MEC) is a biological approach to enhance the growth of high amounts of electroactive biofilm for extracellular electron transfer. The electroactive biofilm degrades the organics by oxidizing them at the anode and producing electrical energy. Addition of waste-activated sludge (WAS) with fat grease oil (FOG) produces an optimal reactor environment for microbial growth to enhance the exchange of electrons between cells via microbial electrolysis. The present work aimed to investigate the microbial approach to increase the extracellular electron transfer (EET) in microbial electrolysis cells. Results revealed that metabolites in electroactive microbes (EAM) grow viable cells that initiate high EET at anode sites. At optimum WAS with FOG addition, volatile fatty acid and current generation yield production was 2.94 ± 0.19 g/L and 17.91 ± 7.23 mA, accompanied by COD removal efficiency of 89.5 ± 14.4%, respectively. This study introduces a novel approach to anode biofilm engineering that significantly enhances extracellular electron transfer, offering a fresh perspective on bioenergy production. Our approach, which demonstrates that anodic biofilm enhances intercellular electron transfer, increases NADH-NAD ratio, and increases metabolite yield-fluxes, has the potential to revolutionize bio-electricity production. Results indicated that the electrolysis highlights MEC performance in power generation of 788 mV with 200 mL of anode volume of active viable cells by utilizing WAS with 11% FOG. The achievements of this study provide critical parameters for the anode biofilm engineering, demonstrating how growth cell volume, intercellular electron transfer, and increases in NADH-NAD ratio are evidence of an increase in the EET, compelling evidence for the resilience treatment and efficient current production. These findings are significant in advancing our understanding of bioenergy production.},
}

@article {pmid39352654,
year = {2024},
author = {Ranđelović, M and Dimitrijević, M and Mijatović, S and Ignjatović, A and Arsić-Arsenijević, V and Stojanović-Radić, Z and Hay, R and Otašević, S},
title = {Antifungal susceptibility and biofilm production of Candida species- causative agents of female genital tract infections.},
journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]},
volume = {},
number = {},
pages = {},
pmid = {39352654},
issn = {1678-4405},
abstract = {BACKGROUND: Recurrent vulvovaginal candidosis (RVVC) is a chronic infection affecting 8-10% of women worldwide. Biofilm production of the infecting species and reduced sensitivity to antimycotics could contribute to the recurrence of this infection. This study aimed to examine the biofilm production ability and antifungal susceptibility of genital yeast isolates to determine their virulence potential.

METHODS: Matrix-assisted laser desorption in ionization-time of flight mass spectrometry (MALDI-TOF MS) was used to identify 300 Candida species. Using crystal violet method, strains were categorized into non-producers, weak, moderate, and strong biofilm producers (BFP). Antifungal susceptibility testing was performed using commercial Integral System YEASTS Plus test (ISYPT) and broth microdilution method (BMM).

RESULTS: MALDI-TOF MS identified 150 Candida albicans, 124 non-albicans Candida (NAC), and 26 Saccharomyces cerevisiae strains. Within 138 (46.0%) BFP, 23 (16.7%) were strong, 44 (31.9%) moderate, and 71 (51.4%) weak. BMM was done for 43 BFP selected isolates with nystatin MIC ˃1.25 μl, fluconazole MIC ˃64 μl, and clotrimazole MIC ˃1.0 μl determined by ISYPT. Compared to all examined isolates, BMM confirmed that: i) C. albicans and NAC BFP showed low sensitivity to fluconazole (12% and 4%, respectively); ii) all BFP showed low sensitivity to nystatin (12.7% C. albicans, 14.5% NAC, and 23.1% S. cerevisiae); iii) clotrimazole in vitro was the most efficient regarding C. albicans and S. cerevisiae strains, but in 4.0% NAC BFP for this antimycotic higher MIC was established.

CONCLUSION: Novel antimycotics or possible combinations of antifungal agents and natural products could be a new treatment option for RVVC.},
}

@article {pmid39351665,
year = {2024},
author = {Pradhan, L and Hazra, S and Singh, SV and Bajrang, and Upadhyay, A and Pal, BN and Mukherjee, S},
title = {Correction: Surface modification of medical grade biomaterials by using a low-temperature-processed dual functional Ag-TiO2 coating for preventing biofilm formation.},
journal = {Journal of materials chemistry. B},
volume = {},
number = {},
pages = {},
doi = {10.1039/d4tb90157f},
pmid = {39351665},
issn = {2050-7518},
abstract = {Correction for 'Surface modification of medical grade biomaterials by using a low-temperature-processed dual functional Ag-TiO2 coating for preventing biofilm formation' by Lipi Pradhan et al., J. Mater. Chem. B, 2024, https://doi.org/10.1039/D4TB00701H.},
}

@article {pmid39351304,
year = {2024},
author = {Elbakush, AM and Trunschke, O and Shafeeq, S and Römling, U and Gomelsky, M},
title = {Maple compounds prevent biofilm formation in Listeria monocytogenes via sortase inhibition.},
journal = {Frontiers in microbiology},
volume = {15},
number = {},
pages = {1436476},
pmid = {39351304},
issn = {1664-302X},
abstract = {The Pss exopolysaccharide (EPS) enhances the ability of the foodborne pathogen Listeria monocytogenes to colonize and persist on surfaces of fresh fruits and vegetables. Eradicating listeria within EPS-rich biofilms is challenging due to their increased tolerance to disinfectants, desiccation, and other stressors. Recently, we discovered that extracts of maple wood, including maple sap, are a potent source of antibiofilm agents. Maple lignans, such as nortrachelogenin-8'-O-β-D-glucopyranoside and lariciresinol, were found to inhibit the formation of, and promote the dispersion of pre-formed L. monocytogenes EPS biofilms. However, the mechanism remained unknown. Here, we report that these lignans do not affect Pss EPS synthesis or degradation. Instead, they promote EPS detachment, likely by interfering with an unidentified lectin that keeps EPS attached to the cell surfaces. Furthermore, the maple lignans inhibit the activity of L. monocytogenes sortase A (SrtA) in vitro. SrtA is a transpeptidase that covalently anchors surface proteins, including the Pss-specific lectin, to the cell wall peptidoglycan. Consistent with this, deletion of the srtA gene results in Pss EPS detachment from listerial cells. We also identified several additional maple compounds, including epicatechin gallate, isoscopoletin, scopoletin, and abscisic acid, which inhibit L. monocytogenes SrtA activity in vitro and prevent biofilm formation. Molecular modelling indicates that, despite their structural diversity, these compounds preferentially bind to the SrtA active site. Since maple products are abundant and safe for consumption, our finding that they prevent biofilm formation in L. monocytogenes offers a viable source for protecting fresh produce from this foodborne pathogen.},
}

@article {pmid39350533,
year = {2024},
author = {Ge, M and Zhu, W and Mei, J and Hu, T and Yang, C and Lin, H and Shi, J},
title = {Piezoelectric-Enhanced Nanocatalysts Trigger Neutrophil N1 Polarization against Bacterial Biofilm by Disrupting Redox Homeostasis.},
journal = {Advanced materials (Deerfield Beach, Fla.)},
volume = {},
number = {},
pages = {e2409633},
doi = {10.1002/adma.202409633},
pmid = {39350533},
issn = {1521-4095},
support = {2022YFB3804500//National Key R&D Program of China/ ; JCYJ-SHFY-2022-003//Shanghai Pilot Program for Basic Research-Chinese Academy of Science/ ; 52372276//National Natural Science Foundation of China/ ; 82302717//National Natural Science Foundation of China/ ; 22335006//National Natural Science Foundation of China/ ; 21JC1406000//Basic Research Program of Shanghai Municipal Government/ ; 2023262//Youth Innovation Promotion Association of the Chinese Academy of Sciences/ ; //Young Elite Scientists Sponsorship Program by CAST/ ; 22QA1410200//Shanghai Science and Technology Committee Rising-Star Program/ ; 23ZR1472300//Natural Science Foundation of Shanghai/ ; 2021-I2M-5-012//CAMS Innovation Fund for Medical Sciences/ ; 23YF1432200//Shanghai Sailing Program/ ; 2023M732310//China Postdoctoral Science Foundation/ ; },
abstract = {Strategies of manipulating redox signaling molecules to inhibit or activate immune signals have revolutionized therapeutics involving reactive oxygen species (ROS). However, certain diseases with dual resistance barriers to the attacks by both ROS and immune cells, such as bacterial biofilm infections of medical implants, are difficult to eradicate by a single exogenous oxidative stimulus due to the diversity and complexity of the redox species involved. Here, this work demonstrates that metal-organic framework (MOF) nanoparticles capable of disrupting the bacterial ROS-defense system can dismantle bacterial redox resistance and induce potent antimicrobial immune responses in a mouse model of surgical implant infection by simultaneously modulating redox homeostasis and initiating neutrophil N1 polarization in the infection microenvironment. Mechanistically, the piezoelectrically enhanced MOF triggers ROS production by tilting the band structure and acts synergistically with the aurintricarboxylic acid loaded within the MOF, which inhibits the activity of the cystathionine γ-cleaving enzyme. This leads to biofilm structure disruption and antigen exposure through homeostatic imbalance and synergistic activation of neutrophil N1 polarization signals. Thus, this study provides an alternative but promising strategy for the treatment of antibiotic-resistant biofilm infections.},
}

@article {pmid39350452,
year = {2024},
author = {Liu, Z and Wang, J and Qi, L and Wang, J and Xu, H and Yang, H and Liu, J and Liu, L and Feng, G and Zhang, L},
title = {Amino Acid Functionalized SrTiO3 Nanoarrays with Enhanced Osseointegration Through Programmed Rapid Biofilm Elimination and Angiogenesis Controlled by NIR-Driven Gas Therapy.},
journal = {Small (Weinheim an der Bergstrasse, Germany)},
volume = {},
number = {},
pages = {e2407078},
doi = {10.1002/smll.202407078},
pmid = {39350452},
issn = {1613-6829},
support = {82072546//National Natural Science Foundation of China/ ; 82272434//National Natural Science Foundation of China/ ; 2024YFHZ0304//Sichuan Science and Technology Program/ ; 2022ZDZX0029//Sichuan Science and Technology Program/ ; },
abstract = {Bacterial biofilm formation is closely associated with persistent infections of medical implants, which can lead to implantation failure. Additionally, the reconstruction of the vascular network is crucial for achieving efficient osseointegration. Herein, an anti-biofilm nanoplatform based on L-arginine (LA)/new indocyanine green (NICG) that is anchored to strontim titanium oxide (SrTiO3) nano-arrays on a titanium (Ti) substrate by introducing polydopamine (PDA) serving as the interlayer is designed and successfully fabricated. Near-infrared light (NIR) is used to excite NICG, generating reactive oxygen species (ROS) that react with LA to release nitric oxide (NO) molecules. Utilizing the concentration-dependent effect of NO, high power density NIR irradiation applied during the early stage after implantation to release a high concentration of NO, which synergized with the photothermal effect of PDA to eliminate bacterial biofilm. Subsequently, the irradiation power density can be finely down-regulated to reduce the NO concentration in subsequent treatment for accelerating the reconstruction of blood vessels. Meanwhile, SrTiO3 nano-arrays improve the hydrophilicity of the implant surface and slowly release strontium (Sr) ions for continuously optimizing the osteogenic microenvironment. Effective biofilm elimination and revascularization alongside the continuous optimization of the osteogenic microenvironment can significantly enhance the osseointegration of the functionalized Ti implant in in vivo animal experiments.},
}

@article {pmid39350011,
year = {2024},
author = {Tölken, LA and Neufend, JV and Oppegaard, O and Methling, K and Moll, K and Redanz, S and Katsburg, MMD and Ali, MQ and Shumba, P and Kreikemeyer, B and Skrede, S and Fulde, M and Norrby-Teglund, A and Lalk, M and Kittang, BR and Siemens, N},
title = {Streptokinase reduces Streptococcus dysgalactiae subsp. equisimilis biofilm formation.},
journal = {BMC microbiology},
volume = {24},
number = {1},
pages = {378},
pmid = {39350011},
issn = {1471-2180},
mesh = {*Biofilms/drug effects/growth & development ; *Streptokinase/genetics/metabolism ; *Streptococcus/genetics/drug effects/physiology ; Humans ; *Streptococcal Infections/microbiology ; Soft Tissue Infections/microbiology ; Bacterial Proteins/genetics/metabolism ; },
abstract = {BACKGROUND: Streptococcus dysgalactiae subspecies equisimilis (SDSE) is increasingly recognized as an emerging cause of invasive diseases including necrotizing soft tissue infections (NSTIs). In contrast to the closely related Streptococcus pyogenes, SDSE infections mainly affect older and comorbid patients. Biofilm formation has been demonstrated in soft tissue biopsies of S. pyogenes NSTI cases.

RESULTS: Here, we show that bacterial aggregations indicative of biofilms are also present in SDSE NSTI. Although streptokinase (Ska) activity and biofilm formation did not correlate in a diverse set of clinical SDSE isolates, addition of exogenous Ska at an early time point prevented biofilm formation for selected strains. Deletion of ska in SDSE S118 strain resulted in increased biofilm forming capacity. Ska-deficient mutant strain was characterized by a higher metabolic activity and consequent metabolome profiling of biofilms identified higher deposition of a wide range of metabolites as compared to the wild-type.

CONCLUSIONS: Our results argue that Ska suppresses biofilm formation in SDSE independent of its original plasminogen converting activity. However, the impact of biofilms and its consequences for patient outcomes in streptococcal NSTIs remain to be elucidated.},
}

*Biofilms/drug effects/growth & development
*Streptokinase/genetics/metabolism
*Streptococcus/genetics/drug effects/physiology
Humans
*Streptococcal Infections/microbiology
Soft Tissue Infections/microbiology
Bacterial Proteins/genetics/metabolism

@article {pmid39349970,
year = {2024},
author = {Liu, X and Zou, L and Li, B and Di Martino, P and Rittschof, D and Yang, JL and Maki, J and Liu, W and Gu, JD},
title = {Chemical signaling in biofilm-mediated biofouling.},
journal = {Nature chemical biology},
volume = {},
number = {},
pages = {},
pmid = {39349970},
issn = {1552-4469},
support = {32100101//National Natural Science Foundation of China (National Science Foundation of China)/ ; 32370105//National Natural Science Foundation of China (National Science Foundation of China)/ ; 92051103//National Natural Science Foundation of China (National Science Foundation of China)/ ; 31970036//National Natural Science Foundation of China (National Science Foundation of China)/ ; },
abstract = {Biofouling is the undesirable accumulation of living organisms and their metabolites on submerged surfaces. Biofouling begins with adhesion of biomacromolecules and/or microorganisms and can lead to the subsequent formation of biofilms that are predominantly regulated by chemical signals, such as cyclic dinucleotides and quorum-sensing molecules. Biofilms typically release chemical cues that recruit or repel other invertebrate larvae and algal spores. As such, harnessing the biochemical mechanisms involved is a promising avenue for controlling biofouling. Here, we discuss how chemical signaling affects biofilm formation and dispersion in model species. We also examine how this translates to marine biofouling. Both inductive and inhibitory effects of chemical cues from biofilms on macrofouling are also discussed. Finally, we outline promising mitigation strategies by targeting chemical signaling to foster biofilm dispersion or inhibit biofouling.},
}

@article {pmid39349472,
year = {2024},
author = {Davignon, G and Pietrosemoli, N and Benaroudj, N and Soupé-Gilbert, ME and Cagliero, J and Turc, É and Picardeau, M and Guentas, L and Goarant, C and Thibeaux, R},
title = {Leptospira interrogans biofilm transcriptome highlights adaption to starvation and general stress while maintaining virulence.},
journal = {NPJ biofilms and microbiomes},
volume = {10},
number = {1},
pages = {95},
pmid = {39349472},
issn = {2055-5008},
mesh = {*Biofilms/growth & development ; *Leptospira interrogans/genetics/pathogenicity ; Virulence ; *Transcriptome ; Animals ; *Leptospirosis/microbiology ; *Stress, Physiological ; *Gene Expression Regulation, Bacterial ; *Adaptation, Physiological/genetics ; Mice ; Gene Expression Profiling ; Disease Models, Animal ; },
abstract = {Life-threatening Leptospira interrogans navigate a dual existence: surviving in the environment and infecting mammalian hosts. Biofilm formation is presumably an important survival strategy to achieve this process. Understanding the relation between biofilm and virulence might improve our comprehension of leptospirosis epidemiology. Our study focused on elucidating Leptospira's adaptations and regulations involved in such complex microenvironments. To determine the transcriptional profile of Leptospira in biofilm, we compared the transcriptomes in late biofilms and in exponential planktonic cultures. While genes for motility, energy production, and metabolism were downregulated, those governing general stress response, defense against metal stress, and redox homeostasis showed a significant upsurge, hinting at a tailored defensive strategy against stress. Further, despite a reduced metabolic state, biofilm disruption swiftly restored metabolic activity. Crucially, bacteria in late biofilms or resulting from biofilm disruption retained virulence in an animal model. In summary, our study highlights Leptospira's adaptive equilibrium in biofilms: minimizing energy expenditure, potentially aiding in withstanding stresses while maintaining pathogenicity. These insights are important for explaining the survival strategies of Leptospira, revealing that a biofilm lifestyle may confer an advantage in maintaining virulence, an understanding essential for managing leptospirosis across both environmental and mammalian reservoirs.},
}

*Biofilms/growth & development
*Leptospira interrogans/genetics/pathogenicity
Virulence
*Transcriptome
Animals
*Leptospirosis/microbiology
*Stress, Physiological
*Gene Expression Regulation, Bacterial
*Adaptation, Physiological/genetics
Mice
Gene Expression Profiling
Disease Models, Animal

@article {pmid39349363,
year = {2024},
author = {Zeng, T and Liu, J and Cheung, CW and Li, Y and Jia, H and Tse, ECM and Li, Y},
title = {Manganese Complex-Gold Nanoparticle Hybrid for Biofilm Inhibition and Eradication.},
journal = {Chembiochem : a European journal of chemical biology},
volume = {},
number = {},
pages = {e202400500},
doi = {10.1002/cbic.202400500},
pmid = {39349363},
issn = {1439-7633},
abstract = {Biofilms, which are resistant to conventional antimicrobial treatments, pose significant challenges in medical and industrial environments. This study introduces manganese complex-gold nanoparticles (Mn-DPA-AuNPs) as a hybrid strategy for biofilm inhibition and eradication. Upon exposure to green light, these nanoparticles significantly enhance the generation of reactive oxygen species (ROS), including hydrogen peroxide and superoxide. This activity substantially reduces the regrowth potential of the surviving bacteria within the biofilm, with marked efficacy noted in Pseudomonas aeruginosa PAO1. This study highlights the potential of integrating manganese complexes with gold nanoparticles to develop advanced antimicrobial agents against resistant biofilms, offering a promising approach to enhance microbial control in diverse settings.},
}

@article {pmid39347874,
year = {2024},
author = {Yoon, JY and Park, S and Lee, D and Park, OJ and Lee, W and Han, SH},
title = {Lipoteichoic Acid from Lacticaseibacillus rhamnosus GG as a Novel Intracanal Medicament Targeting Enterococcus faecalis Biofilm Formation.},
journal = {Journal of microbiology (Seoul, Korea)},
volume = {},
number = {},
pages = {},
pmid = {39347874},
issn = {1976-3794},
support = {NRF-2018R1A5A2024418//National Research Foundation of Korea/ ; NRF-2022M3A9F3082330//National Research Foundation of Korea/ ; RS-2022-00164722//National Research Foundation of Korea/ ; 02-2023-0039//Seoul National University Bundang Hospital (SNUBH) Research Fund/ ; },
abstract = {The demand for safe and effective endodontic medicaments to control Enterococcus faecalis biofilms, a contributor to apical periodontitis, is increasing. Recently, lipoteichoic acid (LTA) of family Lactobacillaceae has been shown to have anti-biofilm effects against various oral pathogens. Preliminary experiments showed that LTA purified from Lacticaseibacillus rhamnosus GG (Lgg.LTA) was the most effective against E. faecalis biofilms among LTAs from three Lactobacillaceae including L. rhamnosus GG, Lacticaseibacillus casei, and Lactobacillus acidophilus. Therefore, in this study, we investigated the potential of Lgg.LTA as an intracanal medicament in human root canals infected with E. faecalis. Twenty eight dentinal cylinders were prepared from extracted human teeth, where two-week-old E. faecalis biofilms were formed followed by intracanal treatment with sterile distilled water (SDW), N-2 methyl pyrrolidone (NMP), calcium hydroxide (CH), or Lgg.LTA. Bacteria and biofilms that formed in the root canals were analyzed by scanning electron microscopy and confocal laser scanning microscopy. The remaining E. faecalis cells in the root canals after intracanal medicament treatment were enumerated by culturing and counting. When applied to intracanal biofilms, Lgg.LTA effectively inhibited E. faecalis biofilm formation as much as CH, while SDW and NMP had little effect. Furthermore, Lgg.LTA reduced both live and dead bacteria within the dentinal tubules, indicating the possibility of minimal re-infection in the root canals. Collectively, intracanal application of Lgg.LTA effectively inhibited E. faecalis biofilm formation, implying that Lgg.LTA can be used as a novel endodontic medicament.},
}

@article {pmid39347863,
year = {2024},
author = {Klempt, F and Soleimani, M and Wriggers, P and Junker, P},
title = {A Hamilton principle-based model for diffusion-driven biofilm growth.},
journal = {Biomechanics and modeling in mechanobiology},
volume = {},
number = {},
pages = {},
pmid = {39347863},
issn = {1617-7940},
support = {426335750//Deutsche Forschungsgemeinschaft,Germany/ ; },
abstract = {Dense communities of bacteria, also known as biofilms, are ubiquitous in all of our everyday life. They are not only always surrounding us, but are also active inside our bodies, for example in the oral cavity. While some biofilms are beneficial or even necessary for human life, others can be harmful. Therefore, it is highly important to gain an in-depth understanding of biofilms which can be achieved by in vitro or in vivo experiments. Since these experiments are often time-consuming or expensive, in silico models have proven themselves to be a viable tool in assisting the description and analysis of these complicated processes. Current biofilm growth simulations are using mainly two approaches for describing the underlying models. The volumetric approach splits the deformation tensor into a growth and an elastic part. In this approach, the mass never changes, unless some additional constraints are enforced. The density-based approach, on the other hand, uses an evolution equation to update the growing tissue by adding mass. Here, the density stays constant, and no pressure is exerted. The in silico model presented in this work combines the two approaches. Thus, it is possible to capture stresses inside of the biofilm while adding mass. Since this approach is directly derived from Hamilton's principle, it fulfills the first and second law of thermodynamics automatically, which other models need to be checked for separately. In this work, we show the derivation of the model as well as some selected numerical experiments. The numerical experiments show a good phenomenological agreement with what is to be expected from a growing biofilm. The numerical behavior is stable, and we are thus capable of solving complicated boundary value problems. In addition, the model is very reactive to different input parameters, thereby different behavior of various biofilms can be captured without modifying the model.},
}

@article {pmid39346024,
year = {2024},
author = {Gao, X and Wang, H and Wu, Z and Sun, P and Yu, W and Chen, D and Mao, Y and Fang, L and Qian, J and Li, L and Peng, Q and Han, Y},
title = {The Characteristic of Biofilm Formation in ESBL-Producing K. pneumoniae Isolates.},
journal = {The Canadian journal of infectious diseases & medical microbiology = Journal canadien des maladies infectieuses et de la microbiologie medicale},
volume = {2024},
number = {},
pages = {1802115},
pmid = {39346024},
issn = {1712-9532},
abstract = {Klebsiella pneumoniae is a pathogen that commonly causes hospital-acquired infections. Bacterial biofilms are structured bacterial communities that adhere to the surface of objects or biological tissues. In this study, we investigated the genome homology and biofilm formation capacity of ESBL-producing K. pneumoniae. Thirty ESBL-producing K. pneumoniae isolates from 25 inpatients at Ruijin Hospital, Shanghai, were subjected to pulsed-field gel electrophoresis (PFGE) to estimate genomic relatedness. Based on the chromosomal DNA patterns we obtained, we identified 21 PFGE profiles from the 30 isolates, eight of which had high homology indicating that they may have genetic relationships and/or potential clonal advantages within the hospital. Approximately 84% (21/25) of the clinical patients had a history of surgery, urinary tract catheterization, and/or arteriovenous intubation, all of which may have increased the risk for nosocomial infections. Biofilms were observed in 73% (22/30) of the isolates and that strains did not express type 3 fimbriae did not have biofilm formation capacity. Above findings indicated that a high percentage of ESBL-producing K. pneumoniae isolates formed biofilms in vitro and even though two strains with cut-off of PFGE reached 100% similarity, they generated biofilms differently. Besides, the variability in biofilm formation ability may be correlated with the expression of type 3 fimbriae. Thus, we next screened four ESBL-producing K. pneumoniae isolates (Kpn5, Kpn7, Kpn11, and Kpn16) with high homology and significant differences in biofilm formation using PFGE molecular typing, colony morphology, and crystal violet tests. Kpn7 and Kpn16 had stronger biofilm formation abilities compared with Kpn5 and Kpn11. The ability of above four ESBL-producing K. pneumoniae isolates to agglutinate in a mannose-resistant manner or in a mannose-sensitive manner, as well as RNA sequencing-based transcriptome results, showed that type 3 fimbriae play a significant role in biofilm formation. In contrast, type 1 fimbriae were downregulated during biofilm formation. Further research is needed to fully understand the regulatory mechanisms which underlie these processes.},
}

@article {pmid39346023,
year = {2024},
author = {Soltan Dallal, MM and Nasser, A and Karimaei, S},
title = {Characterization of Virulence Genotypes, Antimicrobial Resistance Patterns, and Biofilm Synthesis in Salmonella spp Isolated from Foodborne Outbreaks.},
journal = {The Canadian journal of infectious diseases & medical microbiology = Journal canadien des maladies infectieuses et de la microbiologie medicale},
volume = {2024},
number = {},
pages = {4805228},
pmid = {39346023},
issn = {1712-9532},
abstract = {Salmonella is the main bacterial pathogen that causes foodborne disease, particularly in developing countries. Nontyphoidal Salmonella (NTS) include Enteritidis and Typhimurium as the most prevalent strains which are one of the significant causes of acute gastroenteritis in children. Therefore, identifying the most predominant serovars, types of common contaminated food, and paying attention to their antibiotic resistance are the main factors in the prevention and control strategy of salmonellosis. This study was undertaken to evaluate the prevalence rate of serovars, the biofilm formation, antimicrobial resistance (AMR) status, and phenotypic virulence factors of Salmonella strains isolated from diarrhea samples in some cities of Iran. A total of 40 (10.41%) Salmonella isolates were recovered from 384 diarrhea samples processed and the most common serovar was Salmonella serovar Typhimurium (82.5). Also, all isolates belonging to serovar Typhimurium showed more virulence factors compared to other serovars. The isolates showed a high resistance rate to ampicillin (95%) and nalidixic acid (87.5%), while a low resistance rate was found for chloramphenicol (2.5%). Moreover, significant variances in the capacity of biofilm formation were found between different Salmonella serotypes. The resistance of NTS to extant choice drugs is a potential public health problem. Constant monitoring of AMR pattern and virulence profile of NTS serovars is suggested for the prevention of salmonellosis in humans.},
}

@article {pmid39345232,
year = {2024},
author = {Veach, AM and Steinbrecher, A and Le, M},
title = {Spatial variability of bacterial biofilm communities in a wastewater effluent-impacted suburban stream ecosystem.},
journal = {Microbiology spectrum},
volume = {},
number = {},
pages = {e0424623},
doi = {10.1128/spectrum.04246-23},
pmid = {39345232},
issn = {2165-0497},
abstract = {UNLABELLED: Wastewater discharge is a global threat to freshwater resources. Streams, in particular, are receiving waterbodies that are directly impacted chemically and biologically due to effluent discharge. However, it is largely unknown how wastewater serves as a subsidy or a stressor to aquatic biodiversity, particularly microbiota, over space. Nutrient-diffusing substrata (NDS) were deployed; NDS release nutrients through diffusion into the water column into a wastewater-dependent stream across three reaches. We used N, P, and N + P treatments for the measurement of single nutrient and co-nutrient limitation, and a no-nutrient control. Both algal and total biofilm biomass was measured and the 16S ribosomal RNA genes via targeted amplicon sequencing was used to assess bacterial/archaeal community diversity. Data indicated that total organic matter in biofilms differs spatially with the greatest organic matter (OM) concentrations in the confluence downstream of wastewater inputs. Biofilm OM concentrations were greatest in P and N + P treatments in the confluence site relative to control or N-only treatments. This indicates heterotrophic microbial communities-likely bacteria that dominate stream biofilms-are P-limited in this ecosystem even with upstream wastewater inputs. In conjunction, bacteria/archaeal communities differed the greatest among nutrient treatments versus spatially and had several indicator taxa belonging to Flavobacterium spp. in N treatments relative to controls. Collectively with historical water quality data, we conclude that this wastewater-fed stream is primarily N-enriched but potentially P-limited, which results in significant shifts in biofilm bacterial communities and likely their overall biomass in this urban watershed.

IMPORTANCE: Streams in arid and semi-arid biomes are often dependent on their flow from municipal sources, such as wastewater effluent. However, wastewater has been shown to contain high concentrations of nutrients and chemical pollutants that can potentially harm aquatic ecosystems and their biota. Understanding if and the type of microorganisms that respond to pollution sources, specifically effluent from wastewater treatment facilities, in regions where flow is predominantly from treatment facilities, is critical for developing a predictive monitoring approach for eutrophication or other ecological degradation states for freshwaters.},
}

@article {pmid39345197,
year = {2024},
author = {Wei, Y and Zhang, Y and Zhuang, Y and Tang, Y and Nie, H and Haung, Y and Liu, T and Yang, W and Yan, F and Zhu, Y},
title = {Veillonella parvula acts as a pathobiont promoting the biofilm virulence and cariogenicity of Streptococcus mutans in adult severe caries.},
journal = {Microbiology spectrum},
volume = {},
number = {},
pages = {e0431823},
doi = {10.1128/spectrum.04318-23},
pmid = {39345197},
issn = {2165-0497},
abstract = {Adult severe caries (ASC) brings severe oral dysfunction and treatment difficulties to patients, and yet no clear pathogenic mechanism for it has been found. This study is focused on the composition of dental plaque microbiome profiles in order to identify disease-relevant species and to investigate into their interactions with the S. mutans. Samples of dental plaque were collected for metagenomic analysis. The acidification, aciduricity, oxidative stress tolerance, and gtf (glucosyltransferase) gene expression of S. mutans cocultured with V. parvula which was identified as ASC-related dominant bacterium. The biofilm formation and extracellular exopolysaccharide (EPS) synthesis of dual-strain were analyzed with scanning electron microscopy (SEM), crystal violet (CV) staining, live/dead bacterial staining, and confocal laser scanning microscopy (CLSM). Furthermore, rodent model experiments were performed to validate the in vivo cariogenicity of the dual-species biofilm. The most significantly abundant taxon found associated with ASC was V. parvula. In vitro experiments found that V. parvula can effectively promote S. mutans mature biofilm formation with enhanced acid resistance, hydrogen peroxide detoxicity, and biofilm virulence. Rodent model experiments revealed that V. parvula was incapable of causing disease on its own, but it significantly heightened the biofilm virulence of S. mutans when being co-infected and augmented the progression, quantity, and severity of dental caries. Our findings demonstrated that V. parvula may act as a synergistic pathobiont to modulate the metabolic activity, spatial structure, and pathogenicity of biofilms of S. mutans in the context of ASC.IMPORTANCEAdult severe caries (ASC), as a special type of acute caries, is rarely reported and its worthiness of further study is still in dispute. Yet studies on the etiology of severe caries in adults have not found a clear pathogenic mechanism for it. Knowledge of the oral microbiota is important for the treatment of dental caries. We discovered that the interaction between V. parvula and S. mutans augments the severity of dental caries in vivo, suggesting V. parvula may act as a synergistic pathobiont exacerbating biofilm virulence of S. mutans in ASC. Our findings may improve the understanding of ASC pathogenesis and are likely to provide a basis for planning appropriate therapeutic strategies.},
}

@article {pmid39344640,
year = {2024},
author = {Bamford, NC and Morris, RJ and Prescott, A and Murphy, P and Erskine, E and MacPhee, CE and Stanley-Wall, NR},
title = {TasA Fibre Interactions Are Necessary for Bacillus subtilis Biofilm Structure.},
journal = {Molecular microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/mmi.15315},
pmid = {39344640},
issn = {1365-2958},
support = {BB/P001335/1/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom ; BB/R012415/1/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom ; BB/X002950/1/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom ; ALTF 471-2020//European Molecular Biology Organization/ ; 200208/Z/15/Z/WT_/Wellcome Trust/United Kingdom ; },
abstract = {The extracellular matrix of biofilms provides crucial structural support to the community and protection from environmental perturbations. TasA, a key Bacillus subtilis biofilm matrix protein, forms both amyloid and non-amyloid fibrils. Non-amyloid TasA fibrils are formed via a strand-exchange mechanism, whereas the amyloid-like form involves non-specific self-assembly. We performed mutagenesis of the N-terminus to assess the role of non-amyloid fibrils in biofilm development. We find that the N-terminal tail is essential for the formation of structured biofilms, providing evidence that the strand-exchange fibrils are the active form in the biofilm matrix. Furthermore, we demonstrate that fibre formation alone is not sufficient to give structure to the biofilm. We build an interactome of TasA with other extracellular protein components, and identify important interaction sites. Our results provide insight into how protein-matrix interactions modulate biofilm development.},
}

@article {pmid39343957,
year = {2024},
author = {Samaniego, LVB and Scandelau, SL and Silva, CR and Pratavieira, S and de Oliveira Arnoldi Pellegrini, V and Dabul, ANG and Esmerino, LA and de Oliveira Neto, M and Hernandes, RT and Segato, F and Pileggi, M and Polikarpov, I},
title = {Thermothelomyces thermophilus exo- and endo-glucanases as tools for pathogenic E. coli biofilm degradation.},
journal = {Scientific reports},
volume = {14},
number = {1},
pages = {22576},
pmid = {39343957},
issn = {2045-2322},
support = {2021/08780-1//Fundação de Amparo à Pesquisa do Estado de São Paulo/ ; 306852/2021-7 and 440180/2022-8//Conselho Nacional de Desenvolvimento Científico e Tecnológico/ ; },
mesh = {*Biofilms/growth & development/drug effects ; *Escherichia coli ; Hydrolysis ; Cellulase/metabolism/chemistry ; Hypocreales/enzymology ; },
abstract = {The escalating prevalence of drug-resistant pathogens not only jeopardizes the effectiveness of existing treatments but also increases the complexity and severity of infectious diseases. Escherichia coli is one the most common pathogens across all healthcare-associated infections. Enzymatic treatment of bacterial biofilms, targeting extracellular polymeric substances (EPS), can be used for EPS degradation and consequent increase in susceptibility of pathogenic bacteria to antibiotics. Here, we characterized three recombinant cellulases from Thermothelomyces thermophilus: a cellobiohydrolase I (TthCel7A), an endoglucanase (TthCel7B), and a cellobiohydrolase II (TthCel6A) as tools for hydrolysis of E. coli and Gluconacetobacter hansenii biofilms. Using a design mixture approach, we optimized the composition of cellulases, enhancing their synergistic activity to degrade the biofilms and significantly reducing the enzymatic dosage. In line with the crystalline and ordered structure of bacterial cellulose, the mixture of exo-glucanases (0.5 TthCel7A:0.5 TthCel6A) is effective in the hydrolysis of G. hansenii biofilm. Meanwhile, a mixture of exo- and endo-glucanases is required for the eradication of E. coli 042 and clinical E. coli biofilms with significantly different proportions of the enzymes (0.56 TthCel7B:0.44 TthCel6A and 0.6 TthCel7A:0.4 TthCel7B, respectively). X-ray diffraction pattern and crystallinity index of E. coli cellulose are comparable to those of carboxymethyl cellulose (CMC) substrate. Our results illustrate the complexity of E. coli biofilms and show that successful hydrolysis is achieved by a specific combination of cellulases, with consistent recurrence of TthCel7B endoglucanase.},
}

*Biofilms/growth & development/drug effects
*Escherichia coli
Hydrolysis
Cellulase/metabolism/chemistry
Hypocreales/enzymology

@article {pmid39342710,
year = {2024},
author = {Li, R and Lu, MY and Guo, RB and Duan, H and Ni, BJ and Fu, SF},
title = {Life cycle assessment of hydrogenotrophic denitrification in membrane aerated biofilm reactors for sustainable wastewater treatment.},
journal = {Water research},
volume = {267},
number = {},
pages = {122529},
doi = {10.1016/j.watres.2024.122529},
pmid = {39342710},
issn = {1879-2448},
abstract = {The conventional anaerobic-anoxic-oxic (AAO) process for wastewater treatment is associated with high energy consumption and pollutant emissions due to its reliance on heterotrophic denitrification. In contrast, membrane aerated biofilm reactors (MABR) coupled with hydrogenotrophic denitrification (H2-MABR) offers a more promising alternative. This study conducts a life cycle assessment (LCA) to evaluate the environmental and economic benefits of H2-MABR compared to traditional AAO processes. Results indicate that even with a limited reactor life, the application of MABR in actual wastewater treatment plants can yield over 30 % reduction in environmental and economic impacts. Using CO2 from biogas as a carbon source significantly reduces carbon emissions during the anaerobic stage, while the efficient nitrogen removal minimizes the need for wastewater recirculation and electricity consumption. The H2-driven denitrification process also avoids emissions and secondary pollution risks associated with organic electron donors. Furthermore, coupling H2-MABR with renewable energy source and Power-to-Gas technology further enhances sustainability by ensuring a stable hydrogen supply. Given the significant potential of H2-MABR for improving wastewater treatment, further research and large-scale implementation are highly encouraged.},
}

@article {pmid39342123,
year = {2024},
author = {Elawady, R and Aboulela, AG and Gaballah, A and Ghazal, AA and Amer, AN},
title = {Antimicrobial Sub-MIC induces Staphylococcus aureus biofilm formation without affecting the bacterial count.},
journal = {BMC infectious diseases},
volume = {24},
number = {1},
pages = {1065},
pmid = {39342123},
issn = {1471-2334},
mesh = {*Biofilms/drug effects/growth & development ; *Staphylococcus aureus/drug effects/physiology ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology ; Humans ; *Staphylococcal Infections/microbiology/drug therapy ; Bacterial Load ; Ciprofloxacin/pharmacology ; Gentamicins/pharmacology ; },
abstract = {BACKGROUND: Biofilm formation is an essential virulence factor that creates a highly protected growth mode for Staphylococcus aureus (S. aureus) to survive in any hostile environment. Antibiotic sub-minimal inhibitory concentration (sub-MIC) may modulate the biofilm formation ability of bacterial pathogens, thereby affecting bacterial pathogenesis and infection outcomes. Intense antimicrobial therapy to treat biofilm-associated infections can control the pathogenic infection aggravation but cannot guarantee its complete eradication.

OBJECTIVE: This study aimed to assess the sub-MICs effect of 5 different antimicrobial classes on biofilm-forming capacity among Staphylococcus aureus clinical isolates using three different biofilm quantitation techniques.

METHODS: In this study, the effects of 5 different antimicrobial agents, namely, azithromycin, gentamicin, ciprofloxacin, doxycycline, and imipenem, at sub-MICs of 12.5%, 25%, and 50% were tested on 5 different clinical isolates of S. aureus. The biofilms formed in the absence and presence of different antimicrobial sub-MICs were then assessed using the following three different techniques: the crystal violet (CV) staining method, the quantitative PCR (qPCR) method, and the spread plate method (SPM).

RESULTS: Biofilm formation was significantly induced in 64% of the tested conditions using the CV technique. On the other hand, the qPCR quantifying the total bacterial count and the SPM quantifying the viable bacterial count showed significant induction only in 24% and 17.3%, respectively (Fig. 1). The difference between CV and the other techniques indicates an increase in biofilm biomass without an increase in bacterial growth. As expected, sub-MICs did not reduce the viable cell count, as shown by the SPM. The CV staining method revealed that sub-MICs of imipenem and ciprofloxacin had the highest significance rate (80%) showing an inductive effect on the biofilm development. On the other hand, doxycycline, azithromycin, and gentamicin displayed lower significance rates of 73%, 53%, and 47%, respectively.

CONCLUSION: Exposure to sub-MIC doses of antimicrobial agents induces the biofilm-forming capacity of S. aureus via increasing the total biomass without significantly affecting the bacterial growth of viable count.},
}

*Biofilms/drug effects/growth & development
*Staphylococcus aureus/drug effects/physiology
*Microbial Sensitivity Tests
*Anti-Bacterial Agents/pharmacology
Humans
*Staphylococcal Infections/microbiology/drug therapy
Bacterial Load
Ciprofloxacin/pharmacology
Gentamicins/pharmacology

@article {pmid39342036,
year = {2024},
author = {Shiralizadeh, S and Farmany, A and Shokoohizadeh, L and Pourhajibagher, M and Alikhani, MY and Bahador, A},
title = {Enhancing antimicrobial efficacy against Pseudomonas aeruginosa biofilm through carbon dot-mediated photodynamic inactivation.},
journal = {AMB Express},
volume = {14},
number = {1},
pages = {108},
pmid = {39342036},
issn = {2191-0855},
support = {14000124468 and 14000117209//Vice Chancellor of Research and Technology of Hamadan University of Medical Sciences, Hamadan, IRAN/ ; },
abstract = {Pseudomonas aeruginosa biofilms shield the bacteria from antibiotics and the body's defenses, often leading to chronic infections that are challenging to treat. This study aimed to assess the impact of sub-lethal doses of antimicrobial photodynamic inactivation (sAPDI) utilizing carbon dots (CDs) derived from gentamicin and imipenem on biofilm formation and the expression of genes (pelA and pslA) associated with P. aeruginosa biofilm formation.The anti-biofilm effects of sAPDI were evaluated by exposing P. aeruginosa to sub-minimum biofilm inhibitory concentrations (sub-MBIC) of CDsGEN-NH2, CDsIMP-NH2, CDsGEN-IMP, and CDsIMP-GEN, combined with sub-lethal UVA light irradiation. Biofilm formation ability was assessed by crystal violet (CV) assay and enumeration method. Additionally, the impact of sAPDI on the expression of pelF and pslA genes was evaluated using real-time quantitative polymerase chain reaction (RT-qPCR).Compared to the control group, the sAPDI treatment with CDsGEN-NH2, CDsIMP-NH2, CDsGEN-IMP, and CDsIMP-GEN resulted in a significant reduction in biofilm activity of P. aeruginosa ATCC 27853 (P < 0.0001). The CV assay method demonstrated reductions in optical density of 83.70%, 81.08%, 89.33%, and 75.71%, while the CFU counting method showed reductions of 4.03, 3.76, 4.39, and 3.21 Log10 CFU/mL. qRT-PCR analysis revealed decreased expression of the pelA and pslA genes in P. aeruginosa ATCC 27853 following sAPDI treatment compared to the control group (P < 0.05).The results indicate that sAPDI using CDs derived from gentamicin and imipenem can decrease the biofilm formation of P. aeruginosa and the expression of the pelA and pslA genes associated with its biofilm formation.},
}

@article {pmid39341797,
year = {2024},
author = {Bin Mohammad Muzaki, MZ and Subramoni, S and Summers, S and Kjelleberg, S and Rice, SA},
title = {Klebsiella pneumoniae AI-2 transporters mediate interspecies interactions and composition in a three-species biofilm community.},
journal = {NPJ biofilms and microbiomes},
volume = {10},
number = {1},
pages = {91},
pmid = {39341797},
issn = {2055-5008},
mesh = {*Biofilms/growth & development ; *Klebsiella pneumoniae/genetics/metabolism ; *Pseudomonas aeruginosa/genetics/metabolism ; *Bacterial Proteins/genetics/metabolism ; Microbial Interactions ; Homoserine/analogs & derivatives/metabolism ; Pseudomonas/genetics/metabolism ; Membrane Transport Proteins/metabolism/genetics ; Gene Deletion ; Biomass ; Lactones ; },
abstract = {Biofilms in nature often exist as communities. In this study, an experimental mixed-species community consisting of Pseudomonas aeruginosa, Pseudomonas protegens and Klebsiella pneumoniae was used to investigate how AI-2 transporters affect interspecies interactions and composition. The K. pneumoniae lsrB/lsrD deletion mutants had a 10-25-fold higher concentration of extracellular AI-2 compared to the wild-type. Although these deletion mutants produced monospecies biofilms of similar biomass, the substitution of these mutants for the parental strain significantly altered composition. Dual-species biofilm assays demonstrated that the changes in composition were due to the cumulative effect of pairwise interactions. It was further revealed that K. pneumoniae being present physically in the consortium was important in AI-2 mediating composition in the consortium, and that AI-2 transporters were crucial in achieving maximum biomass in the community. In conclusion, these findings demonstrate that AI-2 transporters mediate interspecies interactions and is important in maintaining the compositional equilibrium of the community.},
}

*Biofilms/growth & development
*Klebsiella pneumoniae/genetics/metabolism
*Pseudomonas aeruginosa/genetics/metabolism
*Bacterial Proteins/genetics/metabolism
Microbial Interactions
Homoserine/analogs & derivatives/metabolism
Pseudomonas/genetics/metabolism
Membrane Transport Proteins/metabolism/genetics
Gene Deletion
Biomass
Lactones

@article {pmid39341189,
year = {2024},
author = {Zhao, Z and Wang, Y and Wei, Y and Peng, G and Wei, T and He, J and Li, R and Wang, Y},
title = {Distinctive patterns of bacterial community succession in the riverine micro-plastisphere in view of biofilm development and ecological niches.},
journal = {Journal of hazardous materials},
volume = {480},
number = {},
pages = {135974},
doi = {10.1016/j.jhazmat.2024.135974},
pmid = {39341189},
issn = {1873-3336},
abstract = {Exploring plastic bacterial community succession is a crucial step in analyzing and predicting the ecological assembly processes of the plastisphere and its associated environmental impacts. However, microbial biofilm development and niche differentiation during plastic bacterial community succession have rarely scarcely considered. Here, we assessed the differences between three microplastics (MPs) and two natural polymers in terms of biofilm development and niche properties during bacterial community succession, and identified a genus of MPs-degrading bacteria with strong competitive potential in the plastisphere. MPs biofilm development exhibits secondary succession characteristics, whereas natural polymer biofilms persist during the primary succession stage. During succession in plastic bacterial communities, the relationship between nutrient resources and microbial competition was reflected in a positive correlation between species competition and niche breadth, which contradicted the common belief that increased nutrient availability leads to reduced competition. Furthermore, the co-occurrence network revealed that specialists were species with greater competitive potential within the plastisphere. Additionally, the MPs-degrading Exiguobacterium genus represented a key taxon in the plastisphere. Our study provides a reliable pathway for revealing the specificity of plastic bacterial community succession from multiple perspectives and enhances the understanding of ecological assembly processes in the plastisphere.},
}

@article {pmid39339644,
year = {2024},
author = {Mahmoud, GA and Rashed, NM and El-Ganainy, SM and Salem, SH},
title = {Unveiling the Neem (Azadirachta indica) Effects on Biofilm Formation of Food-Borne Bacteria and the Potential Mechanism Using a Molecular Docking Approach.},
journal = {Plants (Basel, Switzerland)},
volume = {13},
number = {18},
pages = {},
pmid = {39339644},
issn = {2223-7747},
abstract = {Biofilms currently represent the most prevalent bacterial lifestyle, enabling them to resist environmental stress and antibacterial drugs. Natural antibacterial agents could be a safe solution for controlling bacterial biofilms in food industries without affecting human health and environmental safety. A methanolic extract of Azadirachta indica (neem) leaves was prepared and analyzed using gas chromatography-mass spectrometry for the identification of its phytochemical constituents. Four food-borne bacterial pathogens (Bacillus cereus, Novosphingobium aromaticivorans, Klebsiella pneumoniae, and Serratia marcescens) were tested for biofilm formation qualitatively and quantitatively. The antibacterial and antibiofilm properties of the extract were estimated using liquid cultures and a microtiter plate assay. The biofilm inhibition mechanisms were investigated using a light microscope and molecular docking technique. The methanolic extract contained 45 identified compounds, including fatty acids, ester, phenols, flavonoids, terpenes, steroids, and antioxidants with antimicrobial, anticancer, and anti-inflammatory properties. Substantial antibacterial activity in relation to the extract was recorded, especially at 100 μg/mL against K. pneumoniae and S. marcescens. The extract inhibited biofilm formation at 100 μg/mL by 83.83% (S. marcescens), 73.12% (K. pneumoniae), and 54.4% (N. aromaticivorans). The results indicate efficient biofilm formation by the Gram-negative bacteria S. marcescens, K. pneumoniae, and N. aromaticivorans, giving 0.74, 0.292, and 0.219 OD at 595 nm, respectively, while B. cereus was found to have a low biofilm formation potential, i.e., 0.14 OD at 595 nm. The light microscope technique shows the antibiofilm activities with the biofilm almost disappearing at 75 μg/mL and 100 μg/mL concentrations. This antibiofilm property was attributed to DNA gyrase inhibition as illustrated by the molecular docking approach.},
}

@article {pmid39339292,
year = {2024},
author = {Shi, L and Zhou, X and Qi, P},
title = {Resin Acid Copper Salt, an Interesting Chemical Pesticide, Controls Rice Bacterial Leaf Blight by Regulating Bacterial Biofilm, Motility, and Extracellular Enzymes.},
journal = {Molecules (Basel, Switzerland)},
volume = {29},
number = {18},
pages = {},
pmid = {39339292},
issn = {1420-3049},
support = {32160661//The National Natural Science Foundation of China/ ; 32202359//The National Natural Science Foundation of China/ ; Guikangda K2024-9//The Scientific Research Foundation of Guiyang Healthcare Vocational University/ ; },
mesh = {*Biofilms/drug effects ; *Xanthomonas/drug effects/pathogenicity ; *Plant Diseases/microbiology/prevention & control ; *Copper/chemistry/pharmacology ; *Oryza/microbiology ; Anti-Bacterial Agents/pharmacology/chemistry ; Plant Leaves ; Resins, Plant/pharmacology/chemistry ; },
abstract = {Bacterial virulence plays an important role in infection. Antibacterial virulence factors are effective for preventing crop bacterial diseases. Resin acid copper salt as an effective inhibitor exhibited excellent anti-Xanthomonas oryzae pv. oryzae (Xoo) activity with an EC50 of 50.0 μg mL[-1]. Resin acid copper salt (RACS) can reduce extracellular polysaccharides' (EPS's) biosynthesis by down-regulating gumB relative expression. RACS can also effectively inhibit the bio-mass of Xoo biofilm. It can reduce the activity of Xoo extracellular amylase at a concentration of 100 μg mL[-1]. Meanwhile, the results of virtual computing suggested that RACS is an enzyme inhibitor. RACS displayed good curative activity with a control effect of 38.5%. Furthermore, the result of the phytotoxicity assessment revealed that RACS exhibited slight toxicity compared with the control at a concentration of 200 μg mL[-1]. The curative effect was increased to 45.0% using an additional antimicrobial agent like orange peel essential oil. RACS markedly inhibited bacterial pathogenicity at a concentration of 100 μg mL[-1] in vivo.},
}

*Biofilms/drug effects
*Xanthomonas/drug effects/pathogenicity
*Plant Diseases/microbiology/prevention & control
*Copper/chemistry/pharmacology
*Oryza/microbiology
Anti-Bacterial Agents/pharmacology/chemistry
Plant Leaves
Resins, Plant/pharmacology/chemistry

@article {pmid39338585,
year = {2024},
author = {Hantus, CE and Moppel, IJ and Frizzell, JK and Francis, AE and Nagashima, K and Ryno, LM},
title = {L-Rhamnose Globally Changes the Transcriptome of Planktonic and Biofilm Escherichia coli Cells and Modulates Biofilm Growth.},
journal = {Microorganisms},
volume = {12},
number = {9},
pages = {},
pmid = {39338585},
issn = {2076-2607},
support = {MCB-2226953//National Science Foundation/ ; DBI-1828041//National Science Foundation/ ; Cottrell Scholar Award//Research Corporation for Science Advancement/ ; },
abstract = {L-rhamnose, a naturally abundant sugar, plays diverse biological roles in bacteria, influencing biofilm formation and pathogenesis. This study investigates the global impact of L-rhamnose on the transcriptome and biofilm formation of PHL628 E. coli under various experimental conditions. We compared growth in planktonic and biofilm states in rich (LB) and minimal (M9) media at 28 °C and 37 °C, with varying concentrations of L-rhamnose or D-glucose as a control. Our results reveal that L-rhamnose significantly affects growth kinetics and biofilm formation, particularly reducing biofilm growth in rich media at 37 °C. Transcriptomic analysis through RNA-seq showed that L-rhamnose modulates gene expression differently depending on the temperature and media conditions, promoting a planktonic state by upregulating genes involved in rhamnose transport and metabolism and downregulating genes related to adhesion and biofilm formation. These findings highlight the nuanced role of L-rhamnose in bacterial adaptation and survival, providing insight into potential applications in controlling biofilm-associated infections and industrial biofilm management.},
}

@article {pmid39338564,
year = {2024},
author = {Ikeda, H and Maeda, S},
title = {Characterization of Escherichia coli Persisters from Biofilm Culture: Multiple Dormancy Levels and Multigenerational Memory in Formation.},
journal = {Microorganisms},
volume = {12},
number = {9},
pages = {},
doi = {10.3390/microorganisms12091888},
pmid = {39338564},
issn = {2076-2607},
support = {19K05791//Japan Society for the Promotion of Science/ ; },
abstract = {Persister cells (PCs), a subpopulation occurring within normal cells, exhibit a transient tolerance to antibiotics because of their dormant state. PCs are categorized into two types: type I PCs, which emerge during the stationary phase, and type II PCs, which emerge during the logarithmic phase. Using the conventional colony-forming method, we previously demonstrated that type I PCs of Escherichia coli form more frequently in air-solid biofilm culture than in liquid culture. In the current study, we modified a cell filamentation method as a more efficient and rapid alternative for quantifying PCs. This modified method yielded results consistent with those of the conventional method with 10[3]-10[4] times higher sensitivity and less detection time, within several hours, and further revealed the existence of multiple levels of type I PCs, including a substantial number of deeply dormant cells. This study also discovered a potential epigenetic memory mechanism, spanning several generations (four or six cell divisions), which influences type II PC formation based on prior biofilm experience in E. coli.},
}

@article {pmid39338555,
year = {2024},
author = {Martinet, MG and Lohde, M and Higazy, D and Brandt, C and Pletz, MW and Middelboe, M and Makarewicz, O and Ciofu, O},
title = {Diversification of Pseudomonas aeruginosa Biofilm Populations under Repeated Phage Exposures Decreases the Efficacy of the Treatment.},
journal = {Microorganisms},
volume = {12},
number = {9},
pages = {},
doi = {10.3390/microorganisms12091880},
pmid = {39338555},
issn = {2076-2607},
support = {861323//Marie Skłodowska-Curie grant/ ; 13N15720//Federal Ministry of Education and Research/ ; 19-10-0406//Aase og Ejnar Danielsens Fond/ ; },
abstract = {Phage therapy has been proposed as a therapeutic alternative to antibiotics for the treatment of chronic, biofilm-related P. aeruginosa infections. To gain a deeper insight into the complex biofilm-phage interactions, we investigated in the present study the effect of three successive exposures to lytic phages of biofilms formed by the reference strains PAO1 and PA14 as well as of two sequential clinical P. aeruginosa isolates from the sputum of a patient with cystic fibrosis (CF). The Calgary device was employed as a biofilm model and the efficacy of phage treatment was evaluated by measurements of the biomass stained with crystal violet (CV) and of the cell density of the biofilm bacterial population (CFU/mL) after each of the three phage exposures. The genetic alterations of P. aeruginosa isolates from biofilms exposed to phages were investigated by whole-genome sequencing. We show here that the anti-biofilm efficacy of the phage treatment decreased rapidly with repeated applications of lytic phages on P. aeruginosa strains with different genetic backgrounds. Although we observed the maintenance of a small subpopulation of sensitive cells after repeated phage treatments, a fast recruitment of mechanisms involved in the persistence of biofilms to the phage attack occurred, mainly by mutations causing alterations of the phage receptors. However, mutations causing phage-tolerant phenotypes such as alginate-hyperproducing mutants were also observed. In conclusion, a decreased anti-biofilm effect occurred after repeated exposure to lytic phages of P. aeruginosa biofilms due to the recruitment of different resistance and tolerance mechanisms.},
}

@article {pmid39338515,
year = {2024},
author = {Tentori, EF and Wang, N and Devin, CJ and Richardson, RE},
title = {Treatment of Anaerobic Digester Liquids via Membrane Biofilm Reactors: Simultaneous Aerobic Methanotrophy and Nitrogen Removal.},
journal = {Microorganisms},
volume = {12},
number = {9},
pages = {},
doi = {10.3390/microorganisms12091841},
pmid = {39338515},
issn = {2076-2607},
support = {N/A//Cornell Sloan Fellowship/ ; N/A//Cornell Atkinson Center Academic Venture Fund/ ; N/A//EPA People, Prosperity, and the Planet (EPA-P3) Program/ ; },
abstract = {Anaerobic digestion (AD) produces useful biogas and waste streams with high levels of dissolved methane (CH4) and ammonium (NH4[+]), among other nutrients. Membrane biofilm reactors (MBfRs), which support dissolved methane oxidation in the same reactor as simultaneous nitrification and denitrification (ME-SND), are a potential bubble-less treatment method. Here, we demonstrate ME-SND taking place in single-stage, AD digestate liquid-fed MBfRs, where oxygen (O2) and supplemental CH4 were delivered via pressurized membranes. The effects of two O2 pressures, leading to different O2 fluxes, on CH4 and N removal were examined. MBfRs achieved up to 98% and 67% CH4 and N removal efficiencies, respectively. The maximum N removal rates ranged from 57 to 94 mg N L[-1] d[-1], with higher overall rates observed in reactors with lower O2 pressures. The higher-O2-flux condition showed NO2[-] as a partial nitrification endpoint, with a lower total N removal rate due to low N2 gas production compared to lower-O2-pressure reactors, which favored complete nitrification and denitrification. Membrane biofilm 16S rRNA amplicon sequencing showed an abundance of aerobic methanotrophs (especially Methylobacter, Methylomonas, and Methylotenera) and enrichment of nitrifiers (especially Nitrosomonas and Nitrospira) and anammox bacteria (especially Ca. Annamoxoglobus and Ca. Brocadia) in high-O2 and low-O2 reactors, respectively. Supplementation of the influent with nitrite supported evidence that anammox bacteria in the low-O2 condition were nitrite-limited. This work highlights coupling of aerobic methanotrophy and nitrogen removal in AD digestate-fed reactors, demonstrating the potential application of ME-SND in MBfRs for the treatment of AD's residual liquids and wastewater. Sensor-based tuning of membrane O2 pressure holds promise for the optimization of bubble-less treatment of excess CH4 and NH4[+] in wastewater.},
}

@article {pmid39338470,
year = {2024},
author = {Martinho, I and Braz, M and Duarte, J and Brás, A and Oliveira, V and Gomes, NCM and Pereira, C and Almeida, A},
title = {The Potential of Phage Treatment to Inactivate Planktonic and Biofilm-Forming Pseudomonas aeruginosa.},
journal = {Microorganisms},
volume = {12},
number = {9},
pages = {},
doi = {10.3390/microorganisms12091795},
pmid = {39338470},
issn = {2076-2607},
abstract = {Pseudomonas aeruginosa is a common cause of hospital-acquired infections and exhibits a strong resistance to antibiotics. An alternative treatment option for bacterial infections is the use of bacteriophages (or phages). In this study, two distinct phages, VB_PaD_phPA-G (phPA-G) and VB_PaN_phPA-Intesti (phPA-Intesti), were used as single suspensions or in a phage cocktail to inactivate the planktonic cells and biofilms of P. aeruginosa. Preliminary experiments in culture medium showed that phage phPA-Intesti (reductions of 4.5-4.9 log CFU/mL) outperformed phPA-G (reductions of 0.6-2.6 log CFU/mL) and the phage cocktail (reduction of 4.2 log CFU/mL). Phage phPA-Intesti caused a maximum reduction of 5.5 log CFU/cm[2] in the P. aeruginosa biofilm in urine after 4 h of incubation. The combination of phage phPA-Intesti and ciprofloxacin did not improve the efficacy of bacterial inactivation nor reduce the development of resistant mutants. However, the development of resistant bacteria was lower in the combined treatment with the phage and the antibiotic compared to treatment with the antibiotic alone. This phage lacks known toxins, virulence, antibiotic resistance, and integrase genes. Overall, the results suggest that the use of phage phPA-Intesti could be a potential approach to control urinary tract infections (UTIs), namely those caused by biofilm-producing and multidrug-resistant strains of P. aeruginosa.},
}

@article {pmid39338441,
year = {2024},
author = {Thippani, S and Patel, NJ and Jathan, J and Filush, K and Socarras, KM and DiLorenzo, J and Balasubramanian, K and Gupta, K and Ortiz Aleman, G and Pandya, JM and Kavitapu, VV and Zeng, D and Miller, JC and Sapi, E},
title = {Evidence for the Presence of Borrelia burgdorferi Biofilm in Infected Mouse Heart Tissues.},
journal = {Microorganisms},
volume = {12},
number = {9},
pages = {},
doi = {10.3390/microorganisms12091766},
pmid = {39338441},
issn = {2076-2607},
abstract = {Borrelia burgdorferi, the bacterium responsible for Lyme disease, has been shown to form antimicrobial-tolerant biofilms, which protect it from unfavorable conditions. Bacterial biofilms are known to significantly contribute to severe inflammation, such as carditis, a common manifestation of Lyme disease. However, the role of B. burgdorferi biofilms in the development of Lyme carditis has not been thoroughly investigated due to the absence of an appropriate model system. In this study, we examined heart tissues from mice infected with B. burgdorferi for the presence of biofilms and inflammatory markers using immunohistochemistry (IHC), combined fluorescence in situ hybridization FISH/IHC, 3D microscopy, and atomic force microscopy techniques. Our results reveal that B. burgdorferi spirochetes form aggregates with a known biofilm marker (alginate) in mouse heart tissues. Furthermore, these biofilms induce inflammation, as indicated by elevated levels of murine C-reactive protein near the biofilms. This research provides evidence that B. burgdorferi can form biofilms in mouse heart tissue and trigger inflammatory processes, suggesting that the mouse model is a valuable tool for future studies on B. burgdorferi biofilms.},
}

@article {pmid39338422,
year = {2024},
author = {Thakur, P and Gopalakrishnan, V and Saxena, P and Subramaniam, M and Goh, KM and Peyton, B and Fields, M and Sani, RK},
title = {Influence of Copper on Oleidesulfovibrio alaskensis G20 Biofilm Formation.},
journal = {Microorganisms},
volume = {12},
number = {9},
pages = {},
doi = {10.3390/microorganisms12091747},
pmid = {39338422},
issn = {2076-2607},
support = {1736255//National Science Foundation/ ; 1849206//National Science Foundation/ ; 1920954//National Science Foundation/ ; },
abstract = {Copper is known to have toxic effects on bacterial growth. This study aimed to determine the influence of copper ions on Oleidesulfovibrio alaskensis G20 biofilm formation in a lactate-C medium supplemented with variable copper ion concentrations. OA G20, when grown in media supplemented with high copper ion concentrations of 5, 15, and 30 µM, exhibited inhibited growth in its planktonic state. Conversely, under similar copper concentrations, OA G20 demonstrated enhanced biofilm formation on glass coupons. Microscopic studies revealed that biofilms exposed to copper stress demonstrated a change in cellular morphology and more accumulation of carbohydrates and proteins than controls. Consistent with these findings, sulfur (dsrA, dsrB, sat, aprA) and electron transport (NiFeSe, NiFe, ldh, cyt3) genes, polysaccharide synthesis (poI), and genes involved in stress response (sodB) were significantly upregulated in copper-induced biofilms, while genes (ftsZ, ftsA, ftsQ) related to cellular division were negatively regulated compared to controls. These results indicate that the presence of copper ions triggers alterations in cellular morphology and gene expression levels in OA G20, impacting cell attachment and EPS production. This adaptation, characterized by increased biofilm formation, represents a crucial strategy employed by OA G20 to resist metal ion stress.},
}

@article {pmid39337326,
year = {2024},
author = {Krzyżek, P and Migdał, P and Krzyżanowska, B and Duda-Madej, A},
title = {Optimization of Helicobacter pylori Biofilm Formation in In Vitro Conditions Mimicking Stomach.},
journal = {International journal of molecular sciences},
volume = {25},
number = {18},
pages = {},
doi = {10.3390/ijms25189839},
pmid = {39337326},
issn = {1422-0067},
support = {SUBK.A130.23.057//Wroclaw Medical University/ ; IA/SP/453975/2020//National Centre for Research and Development/ ; },
mesh = {*Biofilms/growth & development/drug effects ; *Helicobacter pylori/physiology ; Humans ; *Coculture Techniques/methods ; Stomach/microbiology ; Helicobacter Infections/microbiology ; Cell Line ; },
abstract = {Helicobacter pylori is one of the most common bacterial pathogens worldwide and the main etiological agent of numerous gastric diseases. The frequency of multidrug resistance of H. pylori is growing and the leading factor related to this phenomenon is its ability to form biofilm. Therefore, the establishment of a proper model to study this structure is of critical need. In response to this, the aim of this original article is to validate conditions of the optimal biofilm development of H. pylori in monoculture and co-culture with a gastric cell line in media simulating human fluids. Using a set of culture-based and microscopic techniques, we proved that simulated transcellular fluid and simulated gastric fluid, when applied in appropriate concentrations, stimulate autoaggregation and biofilm formation of H. pylori. Additionally, using a co-culture system on semi-permeable membranes in media imitating the stomach environment, we were able to obtain a monolayer of a gastric cell line with H. pylori biofilm on its surface. We believe that the current model for H. pylori biofilm formation in monoculture and co-culture with gastric cells in media containing host-mimicking fluids will constitute a platform for the intensification of research on H. pylori biofilms in in vitro conditions that simulate the human body.},
}

*Biofilms/growth & development/drug effects
*Helicobacter pylori/physiology
Humans
*Coculture Techniques/methods
Stomach/microbiology
Helicobacter Infections/microbiology
Cell Line

@article {pmid39335547,
year = {2024},
author = {Pleskova, SN and Bezrukov, NA and Nikolaeva, ED and Boryakov, AV and Kuzina, OV},
title = {Rapid Detection of Acinetobacter baumannii Suspension and Biofilm Nanomotion and Antibiotic Resistance Estimation.},
journal = {Biomedicines},
volume = {12},
number = {9},
pages = {},
doi = {10.3390/biomedicines12092034},
pmid = {39335547},
issn = {2227-9059},
support = {22-14-20001//Russian Science Foundation/ ; },
abstract = {OBJECTIVES: To develop a system for the rapid detection of Acinetobacter baumannii 173-p1 antibiotic resistance (to ensure reliable fixation of bacteria on a cantilever without losing their nanomotion, to show that nanomotion is due to bacterial metabolism, to compare the nanomotion of bacteria in suspension form and inside of the biofilms), to study the sensitivity/resistance of A. baumannii 173-p1 to antibiotics (lincomycin, ceftriaxone and doxycycline) using the oscillation method of atomic force microscopy and to evaluate the sensitivity and speed of the method in comparison with the classical disk diffusion method.

METHODS: The oscillation mode of atomic force microscopy, scanning electron microscopy and the classical disk diffusion method were used for a complex parallel study of A. baumannii 173-p1 antibiotic resistance, which included testing of fixing agents (poly-L-lysine, rosin and fibronectin), comparison of bacterial metabolism in a set of media (normal saline solution, meat-peptone broth and lysogeny broth) and assessment of antibiotic sensitivity/resistance per se.

RESULTS: A method for express testing of Acinetobacter baumannii antibiotic resistance using AFM was developed; it is shown that bacterial nanomotion directly correlates with bacteria metabolic activity and that bacterial nanomotion is more easily detected in suspension form, rather than in biofilms.

CONCLUSION: The express testing method gave results that are completely comparable with the classical disk diffusion test and with the results of morphology studies by the SEM method, but it significantly exceeded them in speed, allowing a conclusion to be made on the sensitivity/resistance of bacteria less than an hour after the start of the diagnostics.},
}

@article {pmid39335057,
year = {2024},
author = {Wang, C and Zhao, J and Lin, Y and Lwin, SZC and El-Telbany, M and Masuda, Y and Honjoh, KI and Miyamoto, T},
title = {Characterization of Two Novel Endolysins from Bacteriophage PEF1 and Evaluation of Their Combined Effects on the Control of Enterococcus faecalis Planktonic and Biofilm Cells.},
journal = {Antibiotics (Basel, Switzerland)},
volume = {13},
number = {9},
pages = {},
doi = {10.3390/antibiotics13090884},
pmid = {39335057},
issn = {2079-6382},
abstract = {Endolysin, a bacteriophage-derived lytic enzyme, has emerged as a promising alternative antimicrobial agent against rising multidrug-resistant bacterial infections. Two novel endolysins LysPEF1-1 and LysPEF1-2 derived from Enterococcus phage PEF1 were cloned and overexpressed in Escherichia coli to test their antimicrobial efficacy against multidrug-resistant E. faecalis strains and their biofilms. LysPEF1-1 comprises an enzymatically active domain and a cell-wall-binding domain originating from the NLPC-P60 and SH3 superfamilies, while LysPEF1-2 contains a putative peptidoglycan recognition domain that belongs to the PGRP superfamily. LysPEF1-1 was active against 89.86% (62/69) of Enterococcus spp. tested, displaying a wider antibacterial spectrum than phage PEF1. Moreover, two endolysins demonstrated lytic activity against additional gram-positive and gram-negative species pretreated with chloroform. LysPEF1-1 showed higher activity against multidrug-resistant E. faecalis strain E5 than LysPEF1-2. The combination of two endolysins effectively reduced planktonic cells of E5 in broth and was more efficient at inhibiting biofilm formation and removing biofilm cells of E. faecalis JCM 7783[T] than used individually. Especially at 4 °C, they reduced viable biofilm cells by 4.5 log after 2 h of treatment on glass slide surfaces. The results suggest that two novel endolysins could be alternative antimicrobial agents for controlling E. faecalis infections.},
}

@article {pmid39335053,
year = {2024},
author = {Aleksic Sabo, V and Škorić, D and Jovanović-Šanta, S and Knezevic, P},
title = {Exploring Biofilm-Related Traits and Bile Salt Efficacy as Anti-Biofilm Agents in MDR Acinetobacter baumannii.},
journal = {Antibiotics (Basel, Switzerland)},
volume = {13},
number = {9},
pages = {},
doi = {10.3390/antibiotics13090880},
pmid = {39335053},
issn = {2079-6382},
support = {451-03-66/2024-03/ 200125 & 451-03-65/2024-03/200125//Ministry of Science, Technological Development and Innovation of the Republic of Serbia/ ; },
abstract = {Acinetobacter baumannii has been designated as a critical priority pathogen by the World Health Organization for the development of novel antimicrobial agents. This study aimed to investigate both the phenotypic and genotypic traits of multidrug-resistant (MDR) A. baumannii strains, along with the effects of natural bile salts on biofilm formation. The research analyzed phenotypic traits, including autoaggregation, hydrophobicity, twitching motility, lectin production, and biofilm formation, as well as genotypic traits such as the presence of bap and blaPER-1 genes in twenty wound and eight environmental MDR A. baumannii isolates. While all strains were identified as good biofilm producers, no statistically significant correlation was detected between the examined traits and biofilm formation. However, differences in biofilm production were observed between environmental and wound isolates. The natural bile salts Na-cholate, Na-deoxycholate, and Na-chenodeoxycholate demonstrated effective anti-A. baumannii activity (MIC = 0.25-10 mg mL[-1]), with significant anti-biofilm effects. Na-deoxycholate and Na-chenodeoxycholate inhibited 94-100% of biofilm formation at super-MIC concentrations (8-32 mg mL[-1]). This study underscores the urgent need for innovative strategies to combat antibiotic resistance and biofilm formation in A. baumannii, highlighting the potential of natural bile salts as promising biofilm inhibitors and encouraging further research into their modification and combination with other antimicrobials.},
}

@article {pmid39335049,
year = {2024},
author = {Afonso, L and Grzegorczyk, KG and Salomão, JM and Basso, KR and Alves, LC and Silva, MCD and Chryssafidis, AL and Gionco-Cano, B and Yamada-Ogatta, SF and Andrade, G},
title = {Fluopsin C Promotes Biofilm Removal of XDR Acinetobacter baumannii and Presents an Additive Effect with Polymyxin B on Planktonic Cells.},
journal = {Antibiotics (Basel, Switzerland)},
volume = {13},
number = {9},
pages = {},
doi = {10.3390/antibiotics13090875},
pmid = {39335049},
issn = {2079-6382},
support = {439754/2018-6//National Council for Scientific and Technological Development/ ; 406016/2022-4//National Council for Scientific and Technological Development/ ; },
abstract = {Acinetobacter baumannii emerged as one of the most important pathogens for the development of new antimicrobials due to the worldwide detection of isolates resistant to all commercial antibiotics, especially in nosocomial infections. Biofilm formation enhances A. baumannii survival by impairing antimicrobial action, being an important target for new antimicrobials. Fluopsin C (FlpC) is an organocupric secondary metabolite with broad-spectrum antimicrobial activity. This study aimed to evaluate the antibiofilm activity of FlpC in established biofilms of extensively drug-resistant A. baumannii (XDRAb) and the effects of its combination with polymyxin B (PolB) on planktonic cells. XDRAb susceptibility profiles were determined by Vitek 2 Compact, disk diffusion, and broth microdilution. FlpC and PolB interaction was assessed using the microdilution checkerboard method and time-kill kinetics. Biofilms of XDRAb characterization and removal by FlpC exposure were assessed by biomass staining with crystal violet. Confocal Laser Scanning Microscopy was used to determine the temporal removal of the biofilms using DAPI, and cell viability using live/dead staining. The minimum inhibitory concentration (MIC) of FlpC on XDRAb was 3.5 µg mL[-1]. Combining FlpC + PolB culminated in an additive effect, increasing bacterial susceptibility to both antibiotics. FlpC-treated 24 h biofilms reached a major biomass removal of 92.40 ± 3.38% (isolate 230) using 7.0 µg mL[-1] FlpC. Biomass removal occurred significantly over time through the dispersion of the extracellular matrix and decreasing cell number and viability. This is the first report of FlpC's activity on XDRAb and the compound showed a promissory response on planktonic and sessile cells, making it a candidate for the development of a new antimicrobial product.},
}

@article {pmid39334993,
year = {2024},
author = {Li, H and Yang, Z and Khan, SA and Walsh, LJ and Seneviratne, CJ and Ziora, ZM},
title = {Characteristics of Metallic Nanoparticles (Especially Silver Nanoparticles) as Anti-Biofilm Agents.},
journal = {Antibiotics (Basel, Switzerland)},
volume = {13},
number = {9},
pages = {},
doi = {10.3390/antibiotics13090819},
pmid = {39334993},
issn = {2079-6382},
abstract = {Biofilm-associated infections account for a large proportion of chronic diseases and pose a major health challenge. Metal nanoparticles offer a new way to address this problem, by impairing microbial growth and biofilm formation and by causing degradation of existing biofilms. This review of metal nanoparticles with antimicrobial actions included an analysis of 20 years of journal papers and patent applications, highlighting the progress over that time. A network analysis of relevant publications showed a major focus on the eradication of single-species biofilms formed under laboratory conditions, while a bibliometric analysis showed growing interest in combining different types of metal nanoparticles with one another or with antibiotics. The analysis of patent applications showed considerable growth over time, but with relatively few patents progressing to be granted. Overall, this profile shows that intense interest in metal nanoparticles as anti-biofilm agents is progressing beyond the confines of simple laboratory biofilm models and coming closer to clinical application. Looking to the future, metal nanoparticles may provide a sustainable approach to combatting biofilms of drug-resistant bacteria.},
}

@article {pmid39334983,
year = {2024},
author = {Piccirillo, A and Tolosi, R and Mughini-Gras, L and Kers, JG and Laconi, A},
title = {Drinking Water and Biofilm as Sources of Antimicrobial Resistance in Free-Range Organic Broiler Farms.},
journal = {Antibiotics (Basel, Switzerland)},
volume = {13},
number = {9},
pages = {},
doi = {10.3390/antibiotics13090808},
pmid = {39334983},
issn = {2079-6382},
support = {2024BCA1SIDPROGETTI-00139//Department of Comparative Biomedicine and Food Science, University of Padua/ ; },
abstract = {Drinking water distribution systems (DWDSs) represent an ideal environment for biofilm formation, which can harbor pathogenic and antimicrobial-resistant bacteria. This study aimed to assess longitudinally the microbial community composition and antimicrobial resistance (AMR), as determined by 16S rRNA NGS and qPCR, respectively, in drinking water (DW) and biofilm from DWDSs, as well as faeces, of free-range organic broiler farms. The role of DWDSs in AMR gene (ARG) dissemination within the farm environment and transmission to animals, was also assessed. DW and biofilm microbial communities differed from those of faecal samples. Moreover, potentially pathogenic and opportunistic bacteria (e.g., Staphylococcaceae) were identified in water and biofilms. High prevalence and abundance of ARGs conferring resistance to carbapenems (i.e., blaNDM), 3rd and 4th generation cephalosporins (i.e., blaCMY-2), (fluoro)quinolones (i.e., qnrS), and polymyxins (i.e., mcr-3 and mcr-5) were detected in DW, biofilm, and faecal samples, which is of concern for both animal and human health. Although other factors (e.g., feed, pests, and wildlife) may contribute to the dissemination of AMR in free-range organic poultry farms, this study indicates that DWDSs can also play a role.},
}

@article {pmid39333832,
year = {2024},
author = {},
title = {Explore advanced techniques for biofilm control.},
journal = {British dental journal},
volume = {237},
number = {6},
pages = {504},
doi = {10.1038/s41415-024-7932-4},
pmid = {39333832},
issn = {1476-5373},
mesh = {*Biofilms ; Humans ; },
}

*Biofilms
Humans

@article {pmid39333031,
year = {2024},
author = {Pal, S and Jain, D and Biswal, S and Rastogi, SK and Kumar, G and Ghosh, AS},
title = {The physiological role of Acinetobacter baumannii DacC is exerted through influencing cell shape, biofilm formation, the fitness of survival and manifesting DD-carboxypeptidase and beta-lactamase dual-enzyme activities.},
journal = {FEMS microbiology letters},
volume = {},
number = {},
pages = {},
doi = {10.1093/femsle/fnae079},
pmid = {39333031},
issn = {1574-6968},
abstract = {With the growing threat of drug-resistant Acinetobacter baumannii, there is an urgent need to comprehensively understand the physiology of this nosocomial pathogen. As penicillin-binding proteins are attractive targets for antibacterial therapy, we have tried to explore the physiological roles of two putative DD-carboxypeptidases, viz., DacC and DacD, in A. baumannii. Surprisingly, the deletion of dacC resulted in a reduced growth rate, loss of rod-shaped morphology, reduction in biofilm-forming ability, and enhanced susceptibility towards beta-lactams. In contrast, the deletion of dacD had no such effect. Interestingly, ectopic expression of dacC restored the lost phenotypes. The ∆dacCD mutant showed properties similar to the ∆dacC mutant. Conversely, in vitro enzyme kinetics assessments reveal that DacD is a stronger DD-CPase than DacC. Finally, we conclude that DacC might have DD-CPase and beta-lactamase activities, whereas DacD is a strong DD-CPase.},
}

@article {pmid39332602,
year = {2024},
author = {Zhou, Y and Chang, J and Zhang, M and Li, X and Luo, X and Li, W and Tian, Z and Zhang, N and Ni, B and Zhang, Y and Lu, R},
title = {GefB, a GGDEF domain-containing protein, affects motility and biofilm formation of Vibrio parahaemolyticus and is regulated by quorum sensing regulators.},
journal = {Gene},
volume = {},
number = {},
pages = {148968},
doi = {10.1016/j.gene.2024.148968},
pmid = {39332602},
issn = {1879-0038},
abstract = {Vibrio parahaemolyticus (V. parahaemolyticus) stands as the predominant etiological agent responsible for gastroenteritis associated with the consumption of seafood. Cyclic di-guanosine monophosphate (c-di-GMP), a secondary messenger in bacteria, controls multiple bacterial behaviors including pathogenesis, the development of biofilms, and motility. The protein GefB (VPA1478), characterized by the presence of a GGDEF domain, inhibits the swarming motility of V. parahaemolyticus. In this study, we showed that deletion of gefB remarkably reduced cellular c-di-GMP level and biofilm formation by V. parahaemolyticus, but significantly enhanced the swimming and swarming motility. In addition, GefB inhibited the polar and lateral flagellar genes but activated genes associated with exopolysaccharide production of V. parahaemolyticus. The data also demonstrated that vpa1477 and gefB are co-transcribed as a single transcriptional unit, designated as vpa1477-gefB. Transcription of vpa1477-gefB was under the collective regulation of the master quorum sensing (QS) regulators AphA and OpaR, which function at low (LCD) and high cell density (HCD), respectively. AphA positively regulated vpa1477-gefB transcription at LCD, whereas OpaR negatively regulated its transcription at HCD. The findings significantly enhance our comprehension of the metabolism and regulatory mechanisms of c-di-GMP in V. parahaemolyticus.},
}

@article {pmid39330701,
year = {2024},
author = {Tort, S and Öztürk, ZC and Kaynak-Onurdağ, F and Mutlu-Ağardan, NB},
title = {Preparation and evaluation the effects of retinoic acid loaded proliposomal nanofibers on microbial biofilm inhibition.},
journal = {Pharmaceutical development and technology},
volume = {},
number = {},
pages = {1-27},
doi = {10.1080/10837450.2024.2411034},
pmid = {39330701},
issn = {1097-9867},
abstract = {The electrospinning method involves the production of different drug delivery applications using various polymers. The production of proliposomes with electrospinning provides the hybridization of two novel drug delivery systems. Retinoic acid, also known as all-trans retinoic acid (ATRA), is a common and effective drug for acne therapy. This study aimed to prepare ATRA-loaded proliposomal nanofibers and evaluate their effectiveness on biofilm inhibition. Blank and ATRA-loaded proliposomal nanofiber formulations were fabricated in various polyvinylpyrrolidone, phosphatidylcholine and cholesterol ratios. TEM images verified the rapid formation of the liposomes after the hydration of nanofibers. The vesicle size, polydispersity index and zeta potential values of self-assembled liposomes were measured. The vesicle size values were found to be 321.9-363.8nm with PDI values varying between 0.332-0.511 and zeta potential values of (-16.8)-(-20.5)mV. ATRA-loaded proliposomal nanofibers provided higher bioadhesion (0.25mJ/cm[2]) than the commercial cream (0.07mJ/cm[2]). The short-term stability results showed that the initial characteristics remained for three months at 4 °C. The proposed ATRA-loaded self-assembled proliposomal system provided antibacterial, fungistatic or fungicidal effects superior to retinoic acid itself and inhibited biofilm formation in lower concentrations. This approach can combine the stability advantage of nanofibers in the dry state with the high effectiveness of liposomes in acne treatment presenting antibacterial and anti-biofilm-forming activity against Candida albicans and Cutibacterium acnes.},
}

@article {pmid39326804,
year = {2024},
author = {Upadhyay, A and Pal, D and Kumar, A},
title = {Cellulase exhibited a therapeutic potential to inhibit Salmonella enterica serovar Typhi biofilm by targeting multiple regulatory proteins of biofilm.},
journal = {Microbial pathogenesis},
volume = {},
number = {},
pages = {106979},
doi = {10.1016/j.micpath.2024.106979},
pmid = {39326804},
issn = {1096-1208},
abstract = {Biofilm-mediated Salmonella enterica serovar Typhi (Salmonella Ser. Typhi) infections are a growing global health issue due to the formation of antibiotic resistance. The study aimed to discover some of the druggable target proteins of Salmonella Ser. Typhi biofilm and antibiofilm enzyme to prevent Salmonella Ser. Typhi biofilm-mediated infection. Enzymatic therapy has demonstrated effective therapeutic results against bacterial infections due to its specificity and high binding capacity to the target. Therefore, this study focused on the computational interaction between the cellulase enzyme and Salmonella Ser. Typhi biofilm targets proteins with help of the various computational experiments such as ADMET (absorption, distribution, metabolism, excretion, and toxicity), protein-protein interactions, MMGBSA, etc. Further, in vitro validations of the typhoidal biofilm and cellulose presence in Salmonella Ser. Typhi biofilm was conducted using Scanning Electron Microscopy (SEM), Fourier transform infrared spectroscopy, and Raman analysis. Additionally, a minimum biofilm inhibitory concentration assay for cellulase was conducted and find out the optimized cellulase concentration which showed its inhibitory effect on the Salmonella Ser. Typhi. The cellulase antibiofilm effect was analyzed with the help of SEM analysis. Further, the cellulose content in Salmonella Ser. Typhi was quantified before and after treatment of cellulase enzyme. As a result, 58.82% cellulose content was decreased due to cellulase treatment in Salmonella Ser. Typhi.From the seven selected typhoidal biofilm regulatory proteins of Salmonella Ser. Typhi, we identified only five potential druggable targets: BcsA, CsgE, OmpR, CsgF, and CsgD. The BcsA protein is responsible for cellulose production in Salmonella Ser. Typhi biofilm. Consequently, cellulose worked as a fascinating drug target in Salmonella Ser. Typhi biofilm. Therefore, we used cellulase as a potential antibiofilm enzyme for target-based disruption of biofilm. The cellulase showed a high binding affinity with all five identified target proteins [BcsA(-205.62 Kcal/mol)> CsgE(-108.20 Kcal/mol)> OmpR(-107.58 Kcal/mol)>CsgF(-73.74 Kcal/mol)> CsgD(-66.61 Kcal/mol)] in the protein-protein interaction analysis. Our computational analysis suggests that the cellulase enzyme may be used as a potential antibiofilm enzyme against Salmonella Ser. Typhi biofilm.},
}

@article {pmid39326803,
year = {2024},
author = {Francis, AL and Namasivayam, SKR and Samrat, K},
title = {Potential of silver nanoparticles synthesized from Justicia adhatoda metabolites for inhibiting biofilm on urinary catheters.},
journal = {Microbial pathogenesis},
volume = {196},
number = {},
pages = {106957},
doi = {10.1016/j.micpath.2024.106957},
pmid = {39326803},
issn = {1096-1208},
abstract = {In the present study, we investigated the anti-biofilm effect of urinary catheters fabricated with biogenic nanoparticles synthesized from metabolites of Justicia adhatoda under in vitro conditions against human pathogenic bacteria. Silver nanoparticles were synthesized in the reaction mixture composed of 2 % w/v of 0.1 M of precursor (silver nitrate) and 0.2 g of the metabolites obtained from ethanolic extract of Justicia adhatoda. Characterization of the nanoparticles was done by UV visible spectroscopy, fourier infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X ray diffraction (XRD) to confirm the structural and functional properties. Primary conformation of nanoparticles synthesis by UV visible spectroscopy revealed the notable absorption spectra at 425 nm with a wavelength shift around 450 nm, likely due to surface plasmon resonance excitation. SEM analysis showed spherical, monodisperse, nano scale particles with a size range of 50-60 nm. Crystaline phase of the synthesized nanoparticles was confirmed by x ray diffraction studies which showed the distinct peaks at (2θ) 27.90, 32.20, 46.30, 54.40, and 67.40, corresponding to (111), (200), (220), (222), and (311) planes of nano scale silver. The biocompatibility of these nanoparticles was assessed through zebrafish embryonic toxicity study which showed more than 90 % of embryos were alive and healthy. No marked changes on the blood cells also confirmed best hemocompatibility of the nanoparticles. Synthesized nanoparticles thus obtained were fabricated on the urinary catheter and the fabrication was confirmed by FTIR and SEM analysis. Notable changes in the absorption peaks, uniform coating and embedding of silver nanoparticles studied by FTIR and SEM analysis confirmed the fabrication of silver nanoparticles. The coated catheters demonstrated significant antibacterial activity against pathogenic bacterial strains, including E. coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853. Anti-biofilm studies, conducted using a modified microtiter plate crystal violet assay, revealed effective inhibition of both bacterial adhesion and biofilm development. 85 % of biofilm inhibition was recorded against both the tested strains. The coating method presented in this study shows promise for enhancing infection resistance in commonly used medical devices like urinary catheters, thus addressing device-associated infections.},
}

@article {pmid39325551,
year = {2024},
author = {Hatshan, MR and Antonyraj, APM and Marunganathan, V and Shaik, MR and Deepak, P and Thiyagarajulu, N and Manivannan, C and Jain, D and Coutinho, HDM and Guru, A and Arockiaraj, J},
title = {Synergistic Action of Vanillic Acid-Coated Titanium Oxide Nanoparticles: Targeting Biofilm Formation Receptors of Dental Pathogens and Modulating Apoptosis Genes for Enhanced Oral Anticancer Activity.},
journal = {Chemistry & biodiversity},
volume = {},
number = {},
pages = {e202402080},
doi = {10.1002/cbdv.202402080},
pmid = {39325551},
issn = {1612-1880},
abstract = {The prevalence of bacterial and fungal infections is caused by S. aureus, S. mutans, E. faecalis, and Candida albicans are often associated with dental illnesses. In the present study, a unique strategy was used to combat these diseases by fabricating titanium dioxide nanoparticles (TiO2 NPs) conjugated with the plant-based molecule vanillic acid (VA). Molecular modeling investigations were performed to better understand the interactions among vanillic acid and dental pathogen receptors using the Autodock program. The findings indicated that VA-TiO2 NPs exhibited strong free radical scavenging activity. Additionally, they showed excellent antibacterial action towards dental pathogens, with a minimum inhibition level of 60 μg/mL. Furthermore, at doses of 15 μg/mL, 30 μg/mL, 60 μg/mL, and 120 μg/mL, VA-TiO2 NPs demonstrated concentration-dependent apoptotic impacts on human oral carcinoma cells. Apoptotic gene over-expression was identified by the molecular perspectives that revealed the anticancer mechanism of VA-TiO2 NPs on KB cells. This study highlights the promising suitability of VA-TiO2 NPs for dental applications due to their robust antioxidant, anticancer, and antimicrobial characteristics. These nanoparticles present an evident prospect for addressing oral pathogen challenges and improving overall oral health.},
}

@article {pmid39325271,
year = {2024},
author = {Kamali, M and Ghaderi, A and Tamimi, P and Firooz, A and Nasiri Kashani, M and Ayatollahi, A and Valizadeh, F and Fattahi, M and Fattahi, M},
title = {Reactive oxygen species-inducing itraconazole and its anti-biofilm activity against resistant Candida parapsilosis sensu lato biofilm cells isolated from patients with recalcitrant onychomycosis.},
journal = {Archives of dermatological research},
volume = {316},
number = {9},
pages = {642},
pmid = {39325271},
issn = {1432-069X},
mesh = {*Itraconazole/pharmacology ; Humans ; *Biofilms/drug effects ; *Reactive Oxygen Species/metabolism ; *Onychomycosis/drug therapy/microbiology ; *Antifungal Agents/pharmacology ; *Drug Resistance, Fungal/drug effects ; *Candida parapsilosis/drug effects/isolation & purification ; Apoptosis/drug effects ; Microbial Sensitivity Tests ; Female ; Nails/microbiology/drug effects ; },
abstract = {Candida parapsilosis was introduced as the second most responsible for nail involvement. The colonization of biotic and abiotic surfaces by Candida spp. can result in the formation of biofilms, which possess a high level of resistance to typical antifungal agents. Since Candida spp. can produce biofilm mass on the surface of the nails, dermatologists should consider appropriate antifungals to eliminate both the planktonic and biofilm cells. The aim of this research was to determine the antifungal efficacy of itraconazole against C. parapsilosis sensu lato biofilm formations, in addition to its static effects. Ten C. parapsilosis sensu lato isolates were enrolled in this study. The use of itraconazole results in the accumulation of reactive oxygen species (ROS) during treatment. In order to verify the correlation between ROS and itraconazole-induced cell death, the viability of cells was analyzed by administering the ROS scavenger Ascorbic acid. The apoptotic features of itraconazole were analyzed using the Annexin V-FITC method. Based on current data, it was found that the generation of intracellular stresses by itraconazole is not observed in cells upon ROS inhibition, emphasizing the importance of intracellular ROS in the apoptotic mechanism of itraconazole. Targeting the oxidative defense system is a powerful point to use ROS-inducing antifungals as a superior choice for more effective therapies in case of recalcitrant onychomycosis.},
}

*Itraconazole/pharmacology
Humans
*Biofilms/drug effects
*Reactive Oxygen Species/metabolism
*Onychomycosis/drug therapy/microbiology
*Antifungal Agents/pharmacology
*Drug Resistance, Fungal/drug effects
*Candida parapsilosis/drug effects/isolation & purification
Apoptosis/drug effects
Microbial Sensitivity Tests
Female
Nails/microbiology/drug effects

@article {pmid39324454,
year = {2024},
author = {Pradhan, A and Shrestha, K and Aryal, S and Shrestha, S},
title = {Dental Biofilm Accumulation and Gingival Health of Teeth with Fixed Single Prosthesis Fabricated by Various Prosthetic Materials.},
journal = {Kathmandu University medical journal (KUMJ)},
volume = {22},
number = {85},
pages = {27-30},
pmid = {39324454},
issn = {1812-2078},
mesh = {Humans ; Female ; Male ; Adult ; Cross-Sectional Studies ; Middle Aged ; *Biofilms ; *Dental Plaque ; Aged ; Periodontal Index ; Crowns ; Ceramics ; Dental Plaque Index ; Young Adult ; Gingivitis ; Gingiva ; },
abstract = {Background Periodontal health plays an important role in maintaining the health of natural teeth as well as in the success of all dental procedures. Fixed single prosthesis (dental crown) can be fabricated with different types of prosthetic restorative materials like Metal, Ceramic, Ceramic fused to metal. These different materials have different affinity for plaque accumulation leading to the development of gingival inflammation and periodontal disease. Objective To determine the amount of Plaque accumulation and gingival health of teeth with a fixed single prosthesis fabricated by various Prosthetic materials. Method This quantitative cross-sectional study was carried out from July 2021 to March 2022. The patients who visited the hospital after six months of use of the prosthesis enrolled and were categorized into three groups according to the material used for the prosthesis metal, ceramic, and metal-ceramic. The periodontal condition was assessed using the plaque index and gingival index. Result A total of 136 patients (78 female and 58 male) were enrolled in the study, with a mean age of 39.44 ± 16.23 years (Range 19 - 70 years). There were 47 patients with ceramic crowns, 39 patients with metallic, and 50 patients with metal ceramic crowns. The mean plaque index of metal, ceramic, and metal-ceramic crowns was found 1.15 ± 0.546, 0.86 ± 0.479, and 0.93 ± 0.498 respectively. Similarly, the mean gingival index of metal, ceramic, and metal-ceramic crown were 1.22 ± 0.56, 0.91 ± 0.48, and 1.09 ± 0.55 respectively. Conclusion The dental biofilm (plaque) accumulation and hence gingival inflammation is less in ceramic crowns than in metal and metal-ceramic crowns.},
}

Humans
Female
Male
Adult
Cross-Sectional Studies
Middle Aged
*Biofilms
*Dental Plaque
Aged
Periodontal Index
Crowns
Ceramics
Dental Plaque Index
Young Adult
Gingivitis
Gingiva

@article {pmid39323765,
year = {2024},
author = {Du, T and Cao, J and Zhang, Z and Xiao, Z and Jiao, J and Song, Z and Du, X and Wang, S},
title = {Thermo-responsive cascade antimicrobial platform for precise biofilm removal and enhanced wound healing.},
journal = {Burns & trauma},
volume = {12},
number = {},
pages = {tkae038},
pmid = {39323765},
issn = {2321-3868},
abstract = {BACKGROUND: Bacterial infection, tissue hypoxia and inflammatory response can hinder infected wound repair. This study aimed to develop a multifunctional specific therapeutic photo-activated release nanosystem [HMPB@MB@AuNPs@PMB@HA (HMAPH)] by loading photosensitizer methylene blue (MB) into hollow mesoporous Prussian blue nanostructures and modifying the surface with gold particles, polymyxin B (PMB) and hydrophilic hyaluronic acid.

METHODS: The HMAPH was characterized using transmission electron microscopy, UV-vis, Fourier-transform infrared spectroscopy, X-ray diffraction and X-ray photon spectroscopy. The photothermal performance, iron ion release and free radical generation of the HMAPH were measured under different conditions to investigate its thermo-responsive cascade reaction. The antibacterial ability of HMAPH was investigated using live/dead fluorescence tests. The morphology and membrane integrity of Pseudomonas aeruginosa (P. aeruginosa) were investigated using transmission electron microscopy. The anti-biofilm activity of HMAPH was evaluated using crystal violet and SYBR Green I staining. Finally, we established a mouse model of a skin wound infected by P. aeruginosa to confirm the in vivo effectiveness of HMAPH. We used immunofluorescent staining, hematoxylin-eosin staining, Masson staining and enzyme-linked immunosorbent assay to examine whether HMAPH promoted wound healing and reduced inflammatory damage.

RESULTS: In this study, hyaluronic acid was decomposed under the action of hyaluronidase. Also, the exposed nanomaterials specifically bound to the outer membrane of P. aeruginosa through PMB to increase the membrane sensitivity to photodynamic treatment. Under dual-light irradiation, a large amount of iron ions released by HMAPH underwent a Fenton reaction with H2O2 in bacteria to generate hydroxyl radicals (•OH), enabling direct killing of cells by hyperthermia. Additionally, the photodynamic activity of MB released by photo-induced activation led to the generation of reactive oxygen species, achieving synergistic and effective inhibition of P. aeruginosa. HMAPH also inhibited biofilm formation and downregulated the expression of virulence factors. In vivo experiments revealed that HMAPH accelerated the healing of P. aeruginosa-infected wounds by promoting angiogenesis and skin regeneration, inhibiting the inflammatory response and promoting M1 to M2 polarization.

CONCLUSIONS: Our study proposed a strategy against bacteria and biofilms through a synergistic photothermal-photodynamic-Fenton reaction, opening up new prospects for combating biofilm-associated infections.},
}

@article {pmid39322446,
year = {2024},
author = {Kim, HS and Kim, M and Kim, Y and Shin, HH and Lee, SW and Ryu, JH},
title = {Antimicrobial adhesive self-healing hydrogels for efficient dental biofilm removal from periodontal tissue.},
journal = {Dental materials : official publication of the Academy of Dental Materials},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.dental.2024.09.012},
pmid = {39322446},
issn = {1879-0097},
abstract = {OBJECTIVES: Oral biofilms, including pathogens such as Porphyromonas gingivalis, are involved in the initiation and progression of various periodontal diseases. However, the treatment of these diseases is hindered by the limited efficacy of many antimicrobial materials in removing biofilms under the harsh conditions of the oral cavity. Our objective is to develop a gel-type antimicrobial agent with optimal physicochemical properties, strong tissue adhesion, prolonged antimicrobial activity, and biocompatibility to serve as an adjunctive treatment for periodontal diseases.

METHODS: Phenylboronic acid-conjugated alginate (Alg-PBA) was synthesized using a carbodiimide coupling agent. Alg-PBA was then combined with tannic acid (TA) to create an Alg-PBA/TA hydrogel. The composition of the hydrogel was optimized to enhance its mechanical strength and tissue adhesiveness. Additionally, the hydrogel's self-healing ability, erosion and release profile, biocompatibility, and antimicrobial activity against P. gingivalis were thoroughly characterized.

RESULTS: The Alg-PBA/TA hydrogels, with a final concentration of 5 wt% TA, exhibited both mechanical properties comparable to conventional Minocycline gel and strong tissue adhesiveness. In contrast, the Minocycline gel demonstrated negligible tissue adhesion. The Alg-PBA/TA hydrogel also retained its rheological properties under repeated 5 kPa stress owing to its self-healing capability, whereas the Minocycline gel showed irreversible changes in rheology after just one stress cycle. Additionally, Alg-PBA/TA hydrogels displayed a sustained erosion and TA release profile with minimal impact on the surrounding pH. Additionally, the hydrogels exhibited potent antimicrobial activity against P. gingivalis, effectively eliminating its biofilm without compromising the viability of MG-63 cells.

SIGNIFICANCE: The Alg-PBA/TA hydrogel demonstrates an optimal combination of mechanical strength, self-healing ability, tissue adhesiveness, excellent biocompatibility, and sustained antimicrobial activity against P. gingivalis. These attributes make it superior to conventional Minocycline gel. Thus, the Alg-PBA/TA hydrogel is a promising antiseptic candidate for adjunctive treatment of various periodontal diseases.},
}

@article {pmid39322184,
year = {2024},
author = {Chavez-Manini, CA and Reza-López, SA and Arzate-Quintana, C and Quiñonez-Flores, CM and Favila-Pérez, MA and Camarillo-Cisneros, J and Castillo-González, AR},
title = {Effect of electric current in viability, biofilm formation and antibiotic resistance of Pseudomonas aeruginosa: A systematic review.},
journal = {Indian journal of medical microbiology},
volume = {},
number = {},
pages = {100735},
doi = {10.1016/j.ijmmb.2024.100735},
pmid = {39322184},
issn = {1998-3646},
abstract = {BACKGROUND: The bactericidal effect of electric current has been studied in various microorganisms such as Pseudomonas aeruginosa. The objective of this review is to identify the experimental parameters with the greatest antibacterial effect in the shortest time.

METHODS: Literature search was conducted in the databases PubMed, Science Direct, and Google Scholar. Only original articles published between 2014-2023 were included, where the effect of electric current on viability, biofilm formation, and/or antibiotic resistance in P. aeruginosa was analyzed. Quality control criteria considered included specifying control and experimental groups, replicates performed, experimental parameters, and study limitations.

RESULTS: Ten studies were included, which involved the strains Xen5, Xen41, PAO1 persistent cells, and PA14. An average reduction of 3.5 log in biofilm formation was observed in the included studies. The electric current parameters that achieved the greatest effect were 500 μA DC with platinum electrodes for 4 days [5.2-5.5 log], 200 μA intermittent with titanium electrodes for 4 days [4.99 log], and 150 ± 60 μA with silver electrodes for 24 hours [4 log]. Complete eradication of PAO1 persistent cells was achieved in 1 hour with a treatment of 70 μA/cm2 DC followed by 1.5 μg/mL tobramycin for 1 hour each.

CONCLUSIONS: The bactericidal effect of electric current is proportional to the exposure time and current intensity. The electrode material influences the effectiveness of the treatment, possibly because of redox reactions, while differences are observed in the effect on the cell membrane and gene expression when using metallic or carbon electrodes, suggesting differences in the mechanism of action.},
}

@article {pmid39321970,
year = {2024},
author = {Ashkar Daw, M and Azrad, M and Peretz, A},
title = {Associations between biofilm formation and virulence factors among clinical Helicobacter pylori isolates.},
journal = {Microbial pathogenesis},
volume = {},
number = {},
pages = {106977},
doi = {10.1016/j.micpath.2024.106977},
pmid = {39321970},
issn = {1096-1208},
abstract = {INTRODUCTION: Helicobacter pylori (H. pylori) causes several gastrointestinal diseases. Its virulence factors contributing to disease development include biofilm formation, cytotoxin-associated gene A (CagA) and vacuolating cytotoxin A (VacA) proteins that induce host tissue damage. In addition, urease activity enables H. pylori growth in the gastric acidic environment. This work aimed to characterize bacterial factors associated with biofilm production among 89 clinical H. pylori isolates, collected from patient gastric biopsies.

METHODS: Biofilm production was detected using the crystal violet method. PCR was performed to determine vacA genotype (s1m1, s1m2, s2m1 and s2m2) and cagA gene presence. Urease activity was measured via the phenol red method. Susceptibility to six antibiotics was assessed by the Etest method.

RESULTS: Most H. pylori isolates produced biofilm. No association was found between biofilm-formation capacity and cagA presence or vacA genotype. Urease activity levels varied across isolates; no association was found between biofilm-formation and urease activity. Clarithromycin resistance was measured in 49% of the isolates. Isolates susceptible to tetracycline were more commonly strong biofilm producers. In contrast, a significantly higher rate of strong biofilm producers was observed among resistant isolates to amoxicillin, levofloxacin and rifampicin, compared to susceptible isolates. Non-biofilm producers were more common among isolates sensitive to rifampicin and metronidazole, compared to resistant isolates.

CONCLUSIONS: Further studies are needed to understand the factors that regulate biofilm production in order to search for treatments for H. pylori biofilm destruction.},
}

@article {pmid39321968,
year = {2024},
author = {Costa, MLVA and Neto, MCS and Fialho, PHDS and Costa, SCR and Araújo, AR and Lopes, AP and Meneses, AKS and de Lima, SG and Vale, GC and Soares, MJDS and de Carvalho, ALM and Quelemes, PV},
title = {Effect of zinc oxide-eugenol endodontic paste on planktonic aggregates and biofilm of Enterococcus faecalis - an atomic force microscopy evaluation.},
journal = {Microbial pathogenesis},
volume = {},
number = {},
pages = {106965},
doi = {10.1016/j.micpath.2024.106965},
pmid = {39321968},
issn = {1096-1208},
abstract = {OBJECTIVE: This work aimed to evaluate the in vitro effect of zinc oxide-eugenol paste (ZOE) on planktonic aggregates (EfPA) and biofilm (EfBio) of Enterococcus faecalis, focusing on their morphological aspects observed and analyzed using atomic force microscopy (AFM).

DESIGN: The eugenol and paste were characterized by Gas Chromatography coupled with Mass Spectrometry (GC-MS) and Fourier Transform Infrared Spectroscopy (FTIR), respectively. The effect of ZOE on EfPA and EfBio was evaluated by a direct-contact test through colony counting and crystal violet staining protocol. AFM images of untreated and treated EfPA and EfBio growth on bovine dentin were obtained to analyze the morphological damage caused by the treatments.

RESULTS: The characterization showed high purity in the eugenol composition and chemical interaction between the components of the paste. A bactericidal effect on aggregates was observed after 6 hours of exposure, and on biofilm after 24 hours of treatment (p < 0.001). A disruptive effect on the biofilm was also evident. AFM images revealed the formation of EfPA, with a notable presence of an exopolysaccharide matrix. After 6 hours of ZOE treatment, there was a significant increase in the size and surface roughness profile of treated cells (p < 0.05). Loss of typical cell morphology was observed after 24 hours. The effect on the biofilm showed a tendency towards a less condensed biofilm pattern in the treated group, with no differences in surface roughness.

CONCLUSION: ZOE presents bactericidal action on EfPA and EfBio, promoting significant morphological changes after treatment, especially in the aggregates.},
}

@article {pmid39321727,
year = {2024},
author = {Wen, C and Li, Q and Zhu, D and Zhong, M and Zhu, S and Xu, H and Li, C and Zhu, S and Caiola, N and Chen, L and Luo, X},
title = {Biofilm-mediated heavy metal bioaccumulation and trophic transfer in a mining-contaminated river.},
journal = {Water research},
volume = {267},
number = {},
pages = {122487},
doi = {10.1016/j.watres.2024.122487},
pmid = {39321727},
issn = {1879-2448},
abstract = {Biofilms, essential for material circulation and energy flow in aquatic ecosystems, markedly enrich heavy metals in water environments. However, the impact of these accumulated metals on organisms feeding on biofilms remains poorly unknown. This study involved a year-long seasonal survey along the Bijiang River, located next to Asia's largest lead (Pb)-zinc (Zn) mine, conducted to investigate the role of biofilms in nutrient and metal transfer in food webs. In total, 355 biotic and abiotic samples, including water, biofilms, and aquatic biota, were analyzed for the presence of eight heavy metals (arsenic [As], cadmium, chromium, copper, Pb, nickel, Zn, and iron) as well as stable carbon (δ[13]C) and nitrogen (δ[15]N) isotopes. Wide ranges of δ[13]C and δ[15]N values indicated diverse dietary carbon sources and trophic positions in the Bijiang River (maximum trophic level: 4.28). A Bayesian mixing model revealed that periphytic biofilms were the dominant basal carbon source, especially in spring, whereas in summer, consumers exploited more diverse food sources, possibly because feeding on spring biofilms enhanced predator feeding efficiency. Metals tended to be biodiluted along food chains owing to their higher concentrations in biofilms and benthic organisms as well as their chemical forms. Although diet did not significantly affect heavy metal accumulation in fish, those relying on biofilms as the main carbon source showed significantly higher As (p = 0.048) and Pb (p = 0.007) levels compared with those relying on C4 plants. Overall, this study highlights the critical role of periphytic biofilms in nutrient and metal dynamics in aquatic food webs.},
}

@article {pmid39321640,
year = {2024},
author = {Yu, W and Wang, Q and Liu, Z and Gan, H and Wu, Q and Guo, N and Zeng, W and Li, S and Liu, Y},
title = {Metal-phenolic network crosslinked nanogel with prolonged biofilm retention for dihydroartemisinin/NIR synergistically enhanced chemodynamic therapy.},
journal = {Journal of colloid and interface science},
volume = {678},
number = {Pt C},
pages = {841-853},
doi = {10.1016/j.jcis.2024.09.168},
pmid = {39321640},
issn = {1095-7103},
abstract = {Chemodynamic therapy (CDT) is emerging as a promising treatment for biofilm infections. However, its effectiveness is significantly hindered by several factors: the body's stable temperature, a limited supply of Fe[2+] ions, and inadequate endogenous levels of H2O2 at the infection sites. Herin, our study introduces MPN-crosslinked hyaluronic acid (HA) nanogels as an effective strategy for treating biofilm-associated infections. The DHA@HA-TA/Fe (DHTF) nanogel is synthesized through the coordination reaction between Fe[2+] ions and tannic acid (TA)-modified HA, with dihydroartemisinin (DHA) encapsulated within the structure. DHTF exhibits pH-/hyaluronidase-responsiveness in the biofilm infection microenvironment, enabling sustained release of DHA as a substitute for H2O2 and Fe[2+] for CDT. The incorporation of Fe[2+]/TA-based MPN and DHA within the nanogels enables photothermal/DHA dually-enhanced CDT, facilitating efficient disruption of biofilm matrices and bacterial eradication through boosting reactive oxygen species production. In vivo studies demonstrate that DHTF exhibit prolonged retention within biofilms. This ensures a sustained release of therapeutic agents and continuous anti-biofilm activity. Eventually, both in vitro and in vivo evaluations consistently confirm the significant anti-biofilm capacity of DHTF. Our findings highlight the potential of DHTF as a promising nanomedicine for biofilm-related infections, offering efficient treatment strategies that could improve clinical management of these challenging conditions.},
}

@article {pmid39319552,
year = {2024},
author = {Antunes Filho, S and Pizzorno Backx, B and Foguel, D},
title = {Green nanotechnology in phytosynthesis and its efficiency in inhibiting bacterial biofilm formation: implications for medicine.},
journal = {Biofouling},
volume = {},
number = {},
pages = {1-15},
doi = {10.1080/08927014.2024.2407036},
pmid = {39319552},
issn = {1029-2454},
abstract = {Nanotechnology is used in several biomedical applications, including antimicrobial and antibiofilm applications using nanomaterials. Bacterial biofilm varies according to the strain; the matrix is very strong and resistant. In this sense, phytosynthesis is an important method for combating bacterial biofilms through the use of metallic nanoparticles (silver, gold, or copper) with increased marketing and technical-scientific potential. In this review, we seek to gather the leading publications on the use of phytosynthesized metallic nanoparticles against bacterial biofilms. Furthermore, this study aims to understand the main characteristics and parameters of these nanomaterials, their antibiofilm efficiency, and the presence or absence of cytotoxicity in these developed technologies.},
}

@article {pmid39319013,
year = {2024},
author = {Muturi, P and Wachira, P and Wagacha, M and Mbae, C and Kavai, S and Muhammed, M and Gunn, JS and Kariuki, S},
title = {Fecal Shedding, Antimicrobial Resistance and In Vitro Biofilm formation on Simulated Gallstones by Salmonella Typhi Isolated from Typhoid Cases and Asymptomatic Carriers in Nairobi, Kenya.},
journal = {International journal of clinical microbiology},
volume = {1},
number = {2},
pages = {23-36},
pmid = {39319013},
issn = {2690-4721},
abstract = {Typhoid fever, caused by the human restricted pathogen Salmonella Typhi, remains a major global public health concern. Even after successful treatment, approximately 3-5% of patients with typhoid fail to clear the bacteria within one year and become chronic carriers. Most typhoid carriers have gallstones in their gallbladder, and biofilm formation on gallstones is highly correlated with chronic carriage. This study's goal was to identify asymptomatic typhoid carriers in an endemic setting in Kenya, and to compare acute versus chronic isolates. A cohort of typhoid fever patients identified through blood and/or stool culture, and their household contacts, were followed up after treatment to detect longitudinal S. Typhi stool shedding. An abdominal ultrasound scan was used to identify individuals with gallstones. A total of 32 index patients and 32 household contacts were successfully followed-up. Gallstones were detected in 4 cases and 1 household contact. The duration of S. Typhi shedding was significantly longer in individuals with gallstones compared to those without, P<0.001. Eighty-three (83) S. Typhi strains were tested for susceptibility to commonly used antimicrobials and examined by in vitro biofilm formation assays. Out of 37 infected individuals, 32.4% had infections caused by multidrug resistant (MDR) S. Typhi strains and only 18.9% were infected by susceptible strains. Non-MDR strains formed significantly better biofilms in vitro than the MDR strains (P<0.001). This study provides data on S. Typhi chronic carriage that will influence public health approaches aimed at reducing typhoid transmission and the burden of infection.},
}

@article {pmid39318902,
year = {2024},
author = {Raju, R and Prasad, AS and S, RK},
title = {Anti-inflammatory and Antioxidant Activity of Neem and Kirata-Induced Silver Nanoparticles Against Oral Biofilm: An In Vitro Study.},
journal = {Cureus},
volume = {16},
number = {8},
pages = {e67708},
pmid = {39318902},
issn = {2168-8184},
abstract = {Introduction Silver nanoparticles have been the most commonly used nanoparticles which could be integrated with plant extracts. The mutually beneficial interaction between neutral plant extracts and nanoparticles reduced the chemical toxicity while promoting synthesis. Azadirachta indica, widely known as the neem plant, has diverse medicinal compounds encompassing antibacterial, antiviral, antiprotozoal, insecticidal, antifungal, and antioxidant properties. Swertia chirata, known as Chirayata in India, stands out for its dual roles as a laxative and appetiser with pronounced antimicrobial and anti-inflammatory qualities. Hence, this study aimed to evaluate the anti-inflammatory and antioxidant properties of silver nanoparticles synthesized using Neem and Kirata extract. Materials and methods The plant extracts of Neem (Azadirachta indica) and Kirata (Swertia chirata) were obtained in powder form. It was later formulated into an extract and stored in a refrigerator at 4 degrees Celsius. The formulated extract of Neem and Kirata was then incorporated with silver nitrate to form a modified silver nanoparticle using a green synthesis approach. The anti-inflammatory activity of Neem and Kirata extract was tested using Bovine Serum Assay and Egg Albumin Assay. The antioxidant activity of the new herbal-formulated Ag nanoparticles was determined by the DPPH ((2,2-diphenyl-1-picrylhydrazyl) assay. Results Based on the anti-inflammatory assays, the Neem and Kirata-induced nanoparticles showed increasing levels of inhibition, while the standard showed slightly higher inhibition at 10, 20 and 30 µL. At 40 µL and 50 µL, both Kirata and Neem (Ag) and the standard showed high levels of inhibition, nearing 75% and above, with the standard consistently showing a marginally higher inhibition percentage. Based on the DPPH assay, the Neem Kirata-induced Ag nanoparticle showed a comparable or slightly higher inhibition percentage compared to the standard. Conclusion The study underscores the potential of Neem and Kirata herbal-based silver nanoparticles as effective anti-inflammatory and antioxidant agents. Future research directions should focus on refining nanoparticle synthesis, investigating mechanisms of action, and exploring additional therapeutic applications in the biomedical and pharmaceutical sectors.},
}

@article {pmid39318870,
year = {2024},
author = {Allen-Taylor, D and Boro, G and Cabato, PM and Mai, C and Nguyen, K and Rijal, G},
title = {Staphylococcus epidermidis biofilm in inflammatory breast cancer and its treatment strategies.},
journal = {Biofilm},
volume = {8},
number = {},
pages = {100220},
pmid = {39318870},
issn = {2590-2075},
abstract = {Bacterial biofilms represent a significant challenge in both clinical and industrial settings because of their robust nature and resistance to antimicrobials. Biofilms are formed by microorganisms that produce an exopolysaccharide matrix, protecting function and supporting for nutrients. Among the various bacterial species capable of forming biofilms, Staphylococcus epidermidis, a commensal organism found on human skin and mucous membranes, has emerged as a prominent opportunistic pathogen, when introduced into the body via medical devices, such as catheters, prosthetic joints, and heart valves. The formation of biofilms by S. epidermidis on these surfaces facilitates colonization and provides protection against host immune responses and antibiotic therapies, leading to persistent and difficult-to-treat infections. The possible involvement of biofilms for breast oncogenesis has recently created the curiosity. This paper therefore delves into S. epidermidis biofilm involvement in breast cancer. S. epidermidis biofilms can create a sustained inflammatory environment through their metabolites and can break DNA in breast tissue, promoting cellular proliferation, angiogenesis, and genetic instability. Preventing biofilm formation primarily involves preventing bacterial proliferation using prophylactic measures and sterilization of medical devices and equipment. In cancer treatment, common modalities include chemotherapy, surgery, immunotherapy, alkylating agents, and various anticancer drugs. Understanding the relationship between anticancer drugs and bacterial biofilms is crucial, especially for those undergoing cancer treatment who may be at increased risk of bacterial infections, for improving patient outcomes. By elucidating these interactions, strategies to prevent or disrupt biofilm formation, thereby reducing the incidence of infections associated with medical devices and implants, can be identified.},
}

@article {pmid39318723,
year = {2024},
author = {Alvim, ALS and Varoto, AA and Martins, E and Rigotti, MA and Ferreira, AM and Dodo, NB and Diniz, MO and Giroti, ALB and Carneiro, LM and Dos Santos Almeida Vaz, E and de Sousa, AFL and de Andrade, D},
title = {Impact of water quality on reprocessing equipment: Assessment of neurosurgical instruments cleaning and biofilm formation in hospital pipes.},
journal = {Journal of infection prevention},
volume = {25},
number = {5},
pages = {161-165},
pmid = {39318723},
issn = {1757-1774},
abstract = {BACKGROUND: The presence of contamination and microorganisms at any stage of processing renders a method unsafe, leading to a high risk of cross-transmission and cross-infection.

OBJECTIVE: The objective of this study was to assess the cleaning quality of aspirator instruments used in neurosurgical procedures.

METHODS: The experimental study was conducted at the materials and sterilization center, as well as the microbiology laboratory, of a philanthropic hospital in Brazil. A study protocol was implemented, which involved the analysis of 10 samples of Yasargil aspirators with varying dimensions. The samples were subjected to protein tests to detect the presence of organic matter and microbiological analysis. Descriptive statistics were used to analyze the data.

RESULTS: The results indicated that 40% of the instruments tested positive for protein after manual cleaning. Furthermore, after automated cleaning, samples showed an increased microbiological load, with Escherichia coli accounting for 20% and Klebsiella aerogenes for 10% of the identified microorganisms.

CONCLUSION: This study provides evidence of failures in the cleaning process of healthcare products and highlights the presence of biofilm in the pipes, thereby compromising the drinking water quality standard.},
}

@article {pmid39318525,
year = {2024},
author = {Váczi, P and Čonková, E and Malinovská, Z},
title = {Synergistic effect of essential oils and chlorhexidine against planktonic and biofilm-forming cells of Malassezia pachydermatis.},
journal = {Veterinary and animal science},
volume = {26},
number = {},
pages = {100397},
pmid = {39318525},
issn = {2451-943X},
abstract = {Malassezia (M.) pachydermatis, is often associated with secondary infection of the skin and external auditory canal in dogs and cats. The treatment of Malassezia infections is based on the local application of antifungals often combined with antiseptics. Due to increased resistance of yeast to commonly used antimycotics, especially in biofilm-forming cells, the use of natural substances, e.g. plant essential oils, appears as a new promised option. In this study, the efficacy of selected plant essential oils (EO) - oregano, rosemary, bergamot, clove, cinnamon, and thyme - in combination with chlorhexidine on both planktonic and biofilm-forming cells of M. pachydermatis, was investigated. The checkerboard test was used to determine the effect of chlorhexidine combined with individual EOs. According to the FICI (fractional inhibitory concentration index) in planktonic cells, most combinations showed additive effect, except for thyme and rosemary EO, where a synergistic effect was found (33.3 % and 16.7 % respectively). In the biofilm-forming cells, a synergistic effect was noted in chlorhexidine combined with bergamot EO, recorded in 6 isolates (33.3 %), and with thyme and oregano EO, detected in 3 isolates (16.7 %). A significant decrease (p ˂ 0.05) was found in FIC (fractional inhibitory concentration) compared to MIC (minimum inhibitory concentration), for both planktonic and biofilm-forming cells. Based on the obtained results, we can conclude that the combination of chlorhexidine with EOs achieved better efficiency than when using each agent alone and made it possible to reduce the concentration of both, and a sufficient antifungal and antibiofilm effect was achieved in M. pachydermatis strains.},
}

@article {pmid39317617,
year = {2024},
author = {Bao, HX and Wang, HL and Wang, ST and Sun, YL and Zhang, XN and Cheng, HY and Qian, ZM and Wang, AJ},
title = {Corrigendum to "Response of sulfur-metabolizing biofilm to external sulfide in element sulfur-based denitrification packed-bed reactor" [Environ. Res. 231 (2023) 116061].},
journal = {Environmental research},
volume = {},
number = {},
pages = {120001},
doi = {10.1016/j.envres.2024.120001},
pmid = {39317617},
issn = {1096-0953},
}

@article {pmid39317560,
year = {2024},
author = {Ahirwar, P and Kozlovskaya, V and Pukkanasut, P and Nikishau, P and Nealy, S and Harber, G and Michalek, SM and Antony, L and Wu, H and Kharlampieva, E and Velu, SE},
title = {Polymer vesicles for the delivery of inhibitors of cariogenic biofilm.},
journal = {Dental materials : official publication of the Academy of Dental Materials},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.dental.2024.09.006},
pmid = {39317560},
issn = {1879-0097},
abstract = {OBJECTIVES: The goal of this study is to develop a novel drug delivery platform for the pH-responsive delivery of biofilm inhibitors as a potential avenue to prevent and treat dental caries.

METHODS: Biofilm and growth inhibition assays were performed in polystyrene microtiter 96-well plates. Docking analysis was performed using the reported GtfB + HA5 co-crystal structure (PDB code: 8fg8) in SeeSAR 13.0.1 software. Polymersome vesicles were assembled from poly(N-vinylpyrrolidone)8-block-poly(dimethylsiloxane)64-block-poly(N-vinylpyrrolidone)8 (PVPON8-PDMS64-PVPON8) triblock copolymer using a nanoprecipitation method. Microbiome analysis of biofilm inhibitors and the in vivo drug release and antivirulence activities of polymersome encapsulated inhibitors have been carried out in a S. mutans induced rat caries model.

RESULTS: Biofilm inhibitors for HA5 and HA6 have shown species-specific selectivity towards S. mutans and the ability to preserve the oral microbiome in a S. mutans induced dental caries model. The inhibitors were encapsulated into pH-responsive block copolymer vesicles to generate polymersome-encapsulated biofilm inhibitors, and their biofilm and growth inhibitory activities against S. mutans and representative strains of oral commensal streptococci have been assessed. A 4-week treatment of S. mutans UA159 infected gnotobiotic rats with 100 µM of polymersome-encapsulated biofilm inhibitor, PEHA5 showed significant reductions in buccal, sulcal, and proximal caries scores compared to an untreated control group.

SIGNIFICANCE: Taken together, our data suggests that the biofilm-selective therapy using the polymersome-encapsulated biofilm inhibitors is a viable approach for the prevention and treatment of dental caries while preserving the oral microbiome.},
}

@article {pmid39317234,
year = {2024},
author = {Keller, S and LuTheryn, G and Gray, M and Lyons, B and Cleveland, RO and Stride, E and Coussios, CC},
title = {Quantitative evaluation of anti-biofilm cavitation activity seeded from microbubbles or protein cavitation nuclei by passive acoustic mapping.},
journal = {Physics in medicine and biology},
volume = {},
number = {},
pages = {},
doi = {10.1088/1361-6560/ad7f1a},
pmid = {39317234},
issn = {1361-6560},
abstract = {Bacterial biofilms represent a major challenge for effective antibiotic therapy as they confer physical and functional changes that protect bacteria from their surrounding environment. In this work, focused ultrasound in combination with cavitation nuclei was used to disrupt biofilms of Staphylococcus aureus and Pseudomonas aeruginosa, both of which are on the World Health Organization's priority list for new antimicrobial research. Approach: Single species biofilms were exposed to ultrasound (0.5 MHz centre frequency, 0.5-1.5 MPa peak rarefactional pressure, 200 cycle pulses, 5 Hz repetition frequency, 30 s duration), in the presence of two different types of cavitation nuclei. Quantitative passive acoustic mapping (PAM) was used to monitor cavitation emissions during treatment using a calibrated linear array. Main Results: It was observed that the cumulative energy of acoustic emissions during treatment was positively correlated with biofilm disruption, with differences between bacterial species attributed to differences in biofilm morphology. PCaN provided increased biofilm reduction compared to microbubbles due in large part to their persistence over the duration of ultrasound exposure. There was also good correlation between the spatial distribution of cavitation as characterized by PAM and the extent of biofilm disruption observed with microscopy. Significance: Collectively, the results from this work indicate the potential broad applicability of cavitation for eliminating biofilms of priority pathogens and the opportunity presented by Passive Acoustic Mapping for real-time monitoring of antimicrobial processes.},
}

@article {pmid39316962,
year = {2024},
author = {Pousty, D and Ma, B and Mathews, C and Halanur, M and Mamane, H and Linden, KG},
title = {Biofilm inactivation using LED systems emitting germicidal UV and antimicrobial blue light.},
journal = {Water research},
volume = {267},
number = {},
pages = {122449},
doi = {10.1016/j.watres.2024.122449},
pmid = {39316962},
issn = {1879-2448},
abstract = {Biofilms have been widely detected in water distribution and water storage systems posing potential risks to drinking water safety by harboring and shedding pathogens. Light-based disinfection methods, such as germicidal ultraviolet (UV) and antimicrobial blue light (aBL), could serve as non-chemical alternatives for biofilm control. This study investigated the inactivation of pure-culture Pseudomonas aeruginosa biofilms and mixed-culture biofilms using three distinct light-based disinfection methods: a low-pressure (LP) UV lamp emitting at 254 nm, a UV light emitting diode (LED) at 270 nm, and an aBL LED at 405 nm. The biofilms were developed on three commonly used materials including polycarbonate (PC), polytetrafluoroethylene (PTFE), and polyvinyl chloride (PVC), to assess the impact of surface characteristics on light-based biofilm inactivation. Our findings show that all selected devices can effectively inactivate pure-culture and mixed-culture biofilms. While both UV devices (LP UV lamp and UV LED) provided significant inactivation at lower fluences (>1 log reduction at 20 mJ/cm[2]), aBL LED achieved significant inactivation at higher fluences for pure culture (maximum log reduction of 3.8 ± 0.5 at > 200,000 mJ/cm[2]). Inactivation performance also varied with surface materials, likely attributed to different surface properties including roughness, hydrophobicity, and surface charge. This study provides important information on using light-based technologies for biofilm control and highlights the effect of surface materials on their inactivation performance.},
}

@article {pmid39315775,
year = {2024},
author = {Laekas-Hameder, M and Daigle, F},
title = {Only time will tell: lipopolysaccharide glycoform and biofilm-formation kinetics in Salmonella species and Escherichia coli.},
journal = {Journal of bacteriology},
volume = {},
number = {},
pages = {e0031824},
doi = {10.1128/jb.00318-24},
pmid = {39315775},
issn = {1098-5530},
abstract = {In Gram-negative bacteria, LPS (lipopolysaccharide) has been thoroughly characterized and has been shown to play a major role in pathogenesis and bacterial defense. In Salmonella and Escherichia coli, LPS also influences biofilm development. However, the overall role of LPS glycoform in biofilm formation has not been conclusively settled, as there is a lack of consensus on the topic. Some studies show that LPS mutants produce less biofilm biomass than the wild-type strains, while others show that they produce more. This review summarizes current knowledge of LPS biosynthesis and explores the impact of defective steps on biofilm-related characteristics, such as motility, adhesion, auto-aggregation, and biomass production in Salmonella and E. coli. Overall, motility tends to decrease, while adhesion and auto-aggregation phenotypes tend to increase in most LPS-mutant strains. Interestingly, biofilm biomass of various LPS mutants revealed a clear pattern dependent on biofilm maturation time. Incubation times of less than 24 h resulted in a biofilm-defective phenotype compared to the wild-type, while incubation exceeding 24 h led to significantly higher levels of biofilm production. This explains conflicting results found in reports describing the same LPS mutations. It is therefore critical to consider the effect of biofilm maturation time to ascertain the effects of LPS glycoform on biofilm phenotype. Underlying reasons for such changes in biofilm kinetics may include changes in signalling systems affecting biofilm maturation and composition, and dynamic LPS modifications. A better understanding of the role of LPS in the evolution and modification of biofilms is crucial for developing strategies to disperse biofilms.},
}

@article {pmid39315276,
year = {2024},
author = {Korkus, J and Sałata, P and Thompson, SA and Paluch, E and Bania, J and Wałecka-Zacharska, E},
title = {The role of cydB gene in the biofilm formation by Campylobacter jejuni.},
journal = {Research square},
volume = {},
number = {},
pages = {},
doi = {10.21203/rs.3.rs-4342718/v1},
pmid = {39315276},
issn = {2693-5015},
abstract = {Campylobacter jejuni is a major cause of food- and water-borne bacterial infections in humans. A key factor helping bacteria to survive adverse environmental conditions is biofilm formation ability. Nonetheless, the molecular basis underlying biofilm formation by C. jejuni remains poorly understood. Around thirty genes involved in the regulation and dynamics of C. jejuni biofilm formation have been described so far. We applied random transposon mutagenesis to identify new biofilm-associated genes in C. jejuni strain 81-176. Of 1350 mutants, twenty-four had a decreased ability to produce biofilm compared to the wild-type strain. Some mutants contained insertions in genes previously reported to affect the biofilm formation process. The majority of identified genes encoded hypothetical proteins. In the library of EZ-Tn5 insertion mutants, we found the cydB gene associated with respiration that was not previously linked with biofilm formation in Campylobacter. To study the involvement of the cydB gene in biofilm formation, we constructed a non-marked deletion cydB mutant together with a complemented mutant. We found that the cydB deletion-mutant formed a weaker biofilm of loosely organized structure and lower volume than the parent strain. In the present study, we demonstrated the role of the cydB gene in biofilm formation by C. jejuni.},
}

@article {pmid39314881,
year = {2024},
author = {Lee, H and Hwang, SH and Shin, H and Ha, NC and Wang, Q and Choi, SH},
title = {Identification and characterization of a small molecule BFstatin inhibiting BrpR, the transcriptional regulator for biofilm formation of Vibrio vulnificus.},
journal = {Frontiers in microbiology},
volume = {15},
number = {},
pages = {1468567},
pmid = {39314881},
issn = {1664-302X},
abstract = {Many pathogenic bacteria form biofilms that are resistant to not only host immune defenses but also antibiotics, posing a need for the development of strategies to control biofilms. In this study, to prevent biofilm formation of the fulminating foodborne pathogen Vibrio vulnificus, chemical libraries were extensively screened to identify a small molecule inhibiting the activity of BrpR, a transcriptional regulator for biofilm genes. Accordingly, the BrpR inhibitor BFstatin [N1-(2-chloro-5-fluorophenyl)-N3-propylmalonamide], with a half-maximal effective concentration of 8.01 μM, was identified. BFstatin did not interfere with bacterial growth or exhibit cytotoxicity to the human epithelial cell line. BFstatin directly bound to BrpR and interrupted its binding to the target promoter DNAs of the downstream genes. Molecular dynamics simulation of the interaction between BFstatin and BrpR proposed that BFstatin modifies the structure of BrpR, especially the DNA-binding domain. Transcriptomic analyses revealed that BFstatin reduces the expression of the BrpR regulon including the cabABC operon and brp locus which contribute to the production of biofilm matrix of V. vulnificus. Accordingly, BFstatin diminished the biofilm levels of V. vulnificus by inhibiting the matrix development in a concentration-dependent manner. Altogether, BFstatin could be an anti-biofilm agent targeting BrpR, thereby rendering V. vulnificus more susceptible to host immune defenses and antibiotics.},
}

@article {pmid39312715,
year = {2024},
author = {Jasim, ES and Kadhum, AS},
title = {Poly-Ether-Ether-Ketone versus dead-soft coaxial bonded retainers: a randomized clinical trial. Part 2: periodontal health and microbial biofilm assessment.},
journal = {European journal of orthodontics},
volume = {46},
number = {5},
pages = {},
doi = {10.1093/ejo/cjae048},
pmid = {39312715},
issn = {1460-2210},
mesh = {Humans ; *Biofilms ; *Benzophenones ; Male ; *Polymers ; Female ; *Ketones ; *Periodontal Index ; *Orthodontic Retainers ; Adolescent ; *Dental Plaque Index ; *Polyethylene Glycols ; Young Adult ; Adult ; Orthodontic Appliance Design ; Periodontal Pocket/microbiology ; Streptococcus mutans/isolation & purification ; Dental Calculus/microbiology ; },
abstract = {BACKGROUND: Retainers have the potential to detrimentally impact periodontal health and contribute to tooth decay.

OBJECTIVES: To investigate periodontal health and bacterial biofilm related to Poly-Ether-Ether-Ketone (PEEK) fixed retainers as compared to Dead-soft coaxial fixed retainer (DSC).

TRIAL DESIGN: A two-arm parallel groups single-centre randomized clinical trial.

METHODS: The trial included patients whose orthodontic treatment was completed and required retainers. Participants were randomly assigned into two retainer groups: PEEK retainers, prepared by computer-aided design and manufacturing into 0.8 mm wire form, and DSC retainers. The objectives included assessing periodontal health through plaque accumulation index (PI), bleeding on probing (BOP), periodontal pocket depth (PPD), gingival index (GI), calculus index (CI), and alveolar bone height (ABH) assessment. Biofilm assessment involved bacteriological screening of aerobic, facultative anaerobic, mutans streptococci, and lactobacilli. The periodontal indices and microbiological screening as well as were assessed at the debonding stage (T0), 1-month (T1), 3-month (T3), and 6-month (T6) after the commencement of the trial, except for the ABH, which was recorded using periapical radiograph at T0 and T6.

BLINDING: Single blinding of participants in addition to the bacteriological specialist.

RESULTS: Initially, the trial enrolled 46 participants, aged between 12 and 28 years, and were randomly assigned to two groups, with 23 participants in each group. Subsequently, one participant withdrew from the trial, resulting in a total of 45 participants whose data were analysed. Assessment of the periodontal indices, excluding the CI (P = .480), revealed statistically but not clinically significant differences between groups after 6-month of retention (P = .016 of PI, P = .020 of BOP, P = .05 of PPD, and P = .01 of GI). There was slight plaque accumulation, normal PPD (approximately 1 mm), healthy to mild gingivitis with a GI of less than 1 and BOP was around 10%. Concerning the ABH, there was a noticeable reduction in its score after 6 months, particularly in the PEEK group, although the difference was not statistically significant (P = .102). Furthermore, the bacteriological viable count did not show any significant difference between the groups during the recall visits.

HARMS: There have been no reported negative consequences.

LIMITATIONS: Blinding the assessor of periodontal indices was not feasible due to the nature of the intervention. The trial follow-up duration was limited.

CONCLUSIONS: Both the PEEK and DSC retainers have comparable impacts on periodontal health and bacterial accumulation and composition during the retention period.

TRIAL REGISTRATION: NCT05557136.},
}

Humans
*Biofilms
*Benzophenones
Male
*Polymers
Female
*Ketones
*Periodontal Index
*Orthodontic Retainers
Adolescent
*Dental Plaque Index
*Polyethylene Glycols
Young Adult
Adult
Orthodontic Appliance Design
Periodontal Pocket/microbiology
Streptococcus mutans/isolation & purification
Dental Calculus/microbiology

@article {pmid39312573,
year = {2024},
author = {Carter, MD and Tran, TM and Cope-Arguello, ML and Weinstein, S and Li, H and Hendrich, CG and Prom, JL and Li, J and Chu, LT and Bui, L and Manikantan, H and Lowe-Power, TM and Allen, C},
title = {Lectins and polysaccharide EPS I have flow-responsive roles in the attachment and biofilm mechanics of plant pathogenic Ralstonia.},
journal = {PLoS pathogens},
volume = {20},
number = {9},
pages = {e1012358},
doi = {10.1371/journal.ppat.1012358},
pmid = {39312573},
issn = {1553-7374},
abstract = {Bacterial biofilm formation and attachment to hosts are mediated by carbohydrate-binding lectins, exopolysaccharides, and their interactions in the extracellular matrix (ECM). During tomato infection Ralstonia pseudosolanacearum (Rps) GMI1000 highly expresses three lectins: LecM, LecF, and LecX. The latter two are uncharacterized. We evaluated the roles in bacterial wilt disease of LecF, a fucose-binding lectin, LecX, a xylose-binding lectin, and the Rps exopolysaccharide EPS I. Interestingly, single and double lectin mutants attached to tomato roots better and formed more biofilm under static conditions in vitro. Consistent with this finding, static bacterial aggregation was suppressed by heterologous expression of lecFGMI1000 and lecXGMI1000 in other Ralstonia strains that naturally lack these lectins. Crude ECM from a ΔlecF/X double mutant was more adhesive than the wild-type ECM, and LecF and LecX increased Rps attachment to ECM. The enhanced adhesiveness of the ΔlecF/X ECM could explain the double mutant's hyper-attachment in static conditions. Unexpectedly, mutating lectins decreased Rps attachment and biofilm viscosity under shear stress, which this pathogen experiences in plant xylem. LecF, LecX, and EPS I were all essential for biofilm development in xylem fluid flowing through cellulose-coated microfluidic channels. These results suggest that under shear stress, LecF and LecX increase Rps attachment by interacting with the ECM and plant cell wall components like cellulose. In static conditions such as on root surfaces and in clogged xylem vessels, the same lectins suppress attachment to facilitate pathogen dispersal. Thus, Rps lectins have a dual biological function that depends on the physical environment.},
}

@article {pmid39312550,
year = {2024},
author = {Korenaga, A and Miyaoka, T and Asami, H and Yamagami, Y and Yoshii, M and Tanaka, S and Nagao, T},
title = {Synergetic inhibitory effect of isopropyl methylphenol-based agents on biofilm formation by Streptococcus mutans.},
journal = {PloS one},
volume = {19},
number = {9},
pages = {e0310926},
pmid = {39312550},
issn = {1932-6203},
mesh = {*Biofilms/drug effects/growth & development ; *Streptococcus mutans/drug effects ; Drug Synergism ; Microbial Sensitivity Tests ; Gene Expression Regulation, Bacterial/drug effects ; Phenols/pharmacology ; Anti-Bacterial Agents/pharmacology ; Castor Oil ; Humans ; Polyethylene Glycols/pharmacology ; },
abstract = {Dental caries and periodontitis are the most common oral diseases in humans and the main causes of tooth loss. Streptococcus mutans is primarily responsible for dental caries and dental plaque, which are triggered by biofilm formation on the tooth surface. In this study, biofilm inhibition by 4-isopropyl-3-methylphenol (IPMP)-based agents, consisting of IPMP and polyoxyethylene-hydrogenated castor oil (POEHCO), was investigated in vitro. Notably, the use of POEHCO in addition to IPMP inhibited S. mutans biofilms more drastically than IPMP alone. Moreover, the effects of IPMP on the expression of biofilm-related genes (gtfB, gtfC, and gtfD) were examined using quantitative real-time PCR. IPMP at sub-minimum inhibitory concentrations significantly downregulated the expression of these genes. These results suggested that the inhibitory effects on biofilm formation were synergistically enhanced by the surfactant and antibiofilm activities of IPMP. Therefore, IPMP-based agents as dentifrices may be useful to prevent oral diseases originating from biofilms.},
}

*Biofilms/drug effects/growth & development
*Streptococcus mutans/drug effects
Drug Synergism
Microbial Sensitivity Tests
Gene Expression Regulation, Bacterial/drug effects
Phenols/pharmacology
Anti-Bacterial Agents/pharmacology
Castor Oil
Humans
Polyethylene Glycols/pharmacology

@article {pmid39311590,
year = {2024},
author = {Farha, AK and Habimana, O and Corke, H},
title = {Guanabenz acetate, an antihypertensive drug repurposed as an inhibitor of Escherichia coli biofilm.},
journal = {Microbiology spectrum},
volume = {},
number = {},
pages = {e0073824},
doi = {10.1128/spectrum.00738-24},
pmid = {39311590},
issn = {2165-0497},
abstract = {UNLABELLED: Biofilms formed by Escherichia coli are composed of amyloid curli and cellulose and have been shown to be linked to pathogenicity, antibiotic resistance, and chronic infections. Guanabenz acetate (GABE), an antihypertensive drug, was identified as a potential strategic repurposing drug due to its biofilm inhibitory properties following an extensive antimicrobial screening assay of 2,202 Food and Drug Administration-approved non-antibiotic agents. The results of this study provide insights into the effectiveness of GABE as a therapeutic alternative against E. coli biofilm-associated infectious diseases.

IMPORTANCE: Biofilm-associated bacterial infections are one of the major problems in medical settings. There are currently limited biofilm inhibitors available for clinical use. Guanabenz acetate, a drug used to treat high blood pressure, was found to be an effective anti-biofilm agent against Escherichia coli. Our results show that this drug can inhibit the production of cellulose and curli amyloid protein, which are the two main components of E. coli biofilms. Our findings highlight the possibility of repurposing a drug to prevent E. coli biofilm formation.},
}

@article {pmid39311303,
year = {2024},
author = {Yaneva, B and Mutafchieva, M and Shentov, P and Tomov, G},
title = {Guided Biofilm Therapy for Management of "Desquamative Gingivitis"-Clinical Cases.},
journal = {Clinics and practice},
volume = {14},
number = {5},
pages = {1931-1939},
pmid = {39311303},
issn = {2039-7275},
abstract = {Background: Desquamative gingivitis is a clinical manifestation often associated with various mucocutaneous disorders, characterized by red, painful, and friable gingiva. It is predominantly seen in middle-aged to elderly females and is typically linked to autoimmune conditions such as lichen planus, pemphigoid, and pemphigus, among others. Due to the chronic pain and difficulty in maintaining personal oral hygiene, professional care becomes crucial. Methods: This article explores the application of guided biofilm therapy as a novel, gentle approach for managing desquamative gingivitis, focusing on three clinical cases. This therapy employs erythritol-based powders for biofilm removal, offering a less abrasive and more comfortable alternative to traditional mechanical plaque removal techniques. Results: The cases demonstrate the effectiveness of guided biofilm therapy in reducing discomfort and improving clinical outcomes in desquamative gingivitis patients, particularly those suffering from mucous membrane pemphigoid, pemphigus vulgaris, and oral lichen planus. Conclusions: The guided biofilm approach underscores the importance of tailored periodontal therapy in managing nonplaque-induced gingival lesions, improving patient compliance and oral health outcomes.},
}

@article {pmid39310685,
year = {2023},
author = {Poje, G and Bilić, M and Dawidowsky, K and Kovač Bilić, L},
title = {BIOFILM AND HISTOPATHOLOGICAL GRADING OF MAXILLARY SINUS MUCOSA IN PATIENTS WITH ANTROCHOANAL POLYPS.},
journal = {Acta clinica Croatica},
volume = {62},
number = {3},
pages = {406-414},
pmid = {39310685},
issn = {1333-9451},
mesh = {Humans ; *Nasal Polyps/pathology/surgery/microbiology ; *Biofilms ; *Maxillary Sinus/microbiology/pathology/surgery ; Male ; Female ; Cross-Sectional Studies ; Adult ; Middle Aged ; Nasal Mucosa/microbiology/pathology ; Microscopy, Electron, Scanning ; Aged ; },
abstract = {The aim of this cross-sectional study was to determine the signs of biofilm in the maxillary sinus of patients with antrochoanal polyps (ACP), and status of the mucosa on which the biofilm occurred. Mucosal samples from maxillary sinus in 40 ACP patients who underwent endoscopic sinus surgery were analyzed histopathologically and by scanning electron microscopy. Results were compared with maxillary mucosa samples of 40 patients without endoscopic and radiological signs of sinus disease. The existence of biofilm and its relation to the degree of histopathological changes according to Terrier classification of chronic mucosal inflammation of maxillary sinus were statistically analyzed. Biofilm was detected in 23 of 40 (57.5%) ACP patients; the incidence was significantly lower in the control group (2/40, 5%). Biofilm was not found in type 1 mucosa according to Terrier classification. In conclusion, biofilm showed a significant incidence in the maxillary sinus mucosa of ACP patients (57.5%). Occasionally, biofilm can be found in patients with no signs of sinus disease, but not on histologically normal mucosa. Results of this study support the theory that biofilm formation does not represent the initial stage of the inflammatory process.},
}

Humans
*Nasal Polyps/pathology/surgery/microbiology
*Biofilms
*Maxillary Sinus/microbiology/pathology/surgery
Male
Female
Cross-Sectional Studies
Adult
Middle Aged
Nasal Mucosa/microbiology/pathology
Microscopy, Electron, Scanning
Aged

@article {pmid39309319,
year = {2024},
author = {Chen, H and Xia, A and Yan, H and Huang, Y and Zhu, X and Zhu, X and Liao, Q},
title = {Mass transfer in heterogeneous biofilms: Key issues in biofilm reactors and AI-driven performance prediction.},
journal = {Environmental science and ecotechnology},
volume = {22},
number = {},
pages = {100480},
pmid = {39309319},
issn = {2666-4984},
abstract = {Biofilm reactors, known for utilizing biofilm formation for cell immobilization, offer enhanced biomass concentration and operational stability over traditional planktonic systems. However, the dense nature of biofilms poses challenges for substrate accessibility to cells and the efficient release of products, making mass transfer efficiency a critical issue in these systems. Recent advancements have unveiled the intricate, heterogeneous architecture of biofilms, contradicting the earlier view of them as uniform, porous structures with consistent mass transfer properties. In this review, we explore six biofilm reactor configurations and their potential combinations, emphasizing how the spatial arrangement of biofilms within reactors influences mass transfer efficiency and overall reactor performance. Furthermore, we discuss how to apply artificial intelligence in processing biofilm measurement data and predicting reactor performance. This review highlights the role of biofilm reactors in environmental and energy sectors, paving the way for future innovations in biofilm-based technologies and their broader applications.},
}

@article {pmid39309185,
year = {2024},
author = {To, D and Blanco Massani, M and Coraça-Huber, DC and Seybold, A and Ricci, F and Zöller, K and Bernkop-Schnürch, A},
title = {Antibiotic-Polyphosphate Nanocomplexes: A Promising System for Effective Biofilm Eradication.},
journal = {International journal of nanomedicine},
volume = {19},
number = {},
pages = {9707-9725},
pmid = {39309185},
issn = {1178-2013},
mesh = {*Biofilms/drug effects ; *Polyphosphates/chemistry/pharmacology ; *Colistin/pharmacology/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; Humans ; *Nanoparticles/chemistry ; *Micrococcus luteus/drug effects ; Particle Size ; Alkaline Phosphatase/metabolism ; Microbial Sensitivity Tests ; Cell Line ; Cell Survival/drug effects ; },
abstract = {PURPOSE: The eradication of bacterial biofilms poses an enormous challenge owing to the inherently low antibiotic susceptibility of the resident microbiota. The complexation of antibiotics with polyphosphate can substantially improve antimicrobial performance.

METHODS: Nanoparticular complexes of the model drug colistin and polyphosphate (CP-NPs) were developed and characterized in terms of their particle size and morphology, polydispersity index (PDI), zeta potential, and cytotoxicity. Enzyme-triggered monophosphate and colistin release from the CP-NPs was evaluated in the presence of alkaline phosphatase (AP). Subsequently, antimicrobial efficacy was assessed by inhibition experiments on planktonic cultures, as well as time-kill assays on biofilms formed by the model organism Micrococcus luteus.

RESULTS: The CP-NPs exhibited a spherical morphology with particle sizes <200 nm, PDI <0.25, and negative zeta potential. They showed reduced cytotoxicity toward two human cell lines and significantly decreased hemotoxicity compared with native colistin. Release experiments with AP verified the enzymatic cleavage of polyphosphate and subsequent release of monophosphate and colistin from CP-NPs. Although CP-NPs were ineffective against planktonic M. luteus cultures, they showed major activity against bacterial biofilms, outperforming native colistin treatment. Strongly elevated AP levels in the biofilm state were identified as a potential key factor for the observed findings.

CONCLUSION: Accordingly, polyphosphate-based nanocomplexes represent a promising tool to tackle bacterial biofilm.},
}

*Biofilms/drug effects
*Polyphosphates/chemistry/pharmacology
*Colistin/pharmacology/chemistry
*Anti-Bacterial Agents/pharmacology/chemistry
Humans
*Nanoparticles/chemistry
*Micrococcus luteus/drug effects
Particle Size
Alkaline Phosphatase/metabolism
Microbial Sensitivity Tests
Cell Line
Cell Survival/drug effects

@article {pmid39309069,
year = {2024},
author = {Ma, X and Wu, Z and Li, J and Yang, Y},
title = {Functional Study of desKR: a Lineage-Specific Two-Component System Positively Regulating Staphylococcus aureus Biofilm Formation.},
journal = {Infection and drug resistance},
volume = {17},
number = {},
pages = {4037-4053},
pmid = {39309069},
issn = {1178-6973},
abstract = {PURPOSE: Biofilms significantly contribute to the persistence and antibiotic resistance of Staphylococcus aureus infections. However, the regulatory mechanisms governing biofilm formation of S. aureus remain not fully elucidated. This study aimed to investigate the function of the S. aureus lineage-specific two-component system, desKR, in biofilm regulation and pathogenicity.

METHODS: Bioinformatic analysis was conducted to assess the prevalence of desKR across various S. aureus lineages and to examine its structural features. The impact of desKR on S. aureus pathogenicity was evaluated using in vivo mouse models, including skin abscess, bloodstream infection, and nasal colonization models. Crystal violet staining and confocal laser scanning microscopy were utilized to examine the impact of desKR on S. aureus biofilm formation. Mechanistic insights into desKR-mediated biofilm regulation were investigated by quantifying polysaccharide intercellular adhesin (PIA) production, extracellular DNA (eDNA) release, autolysis assays, and RT-qPCR.

RESULTS: The prevalence of desKR varied among different S. aureus lineages, with notably low carriage rates in ST398 and ST59 lineages. Deletion of desKR in NCTC8325 strain resulted in decreased susceptibility to β-lactam and glycopeptide antibiotics. Although desKR did not significantly affect acute pathogenicity, the ΔdesKR mutant exhibited significantly reduced nasal colonization and biofilm-forming ability. Overexpression of desKR in naturally desKR-lacking strains (ST398 and ST59) enhanced biofilm formation, suggesting a lineage-independent effect. Phenotypic assays further revealed that the ΔdesKR mutant showed reduced PIA production, decreased eDNA release, and lower autolysis rates. RT-qPCR indicated significant downregulation of icaA, icaD, icaB, and icaC genes, along with upregulation of icaR, whereas autolysis-related genes remained unchanged.

CONCLUSION: The desKR two-component system positively regulates S. aureus biofilm formation in a lineage-independent manner, primarily by modulating PIA synthesis via the ica operon. These findings provide new insights into the molecular mechanisms of biofilm formation in S. aureus and highlight desKR as a potential target for therapeutic strategies aimed at combating biofilm-associated infections.},
}

@article {pmid39306818,
year = {2024},
author = {Szermer-Olearnik, B and Filik-Matyjaszczyk, K and Ciekot, J and Czarny, A},
title = {The Hydrophobic Stabilization of Pseudomonas aeruginosa Bacteriophage F8 and the Influence of Modified Bacteriophage Preparation on Biofilm Degradation.},
journal = {Current microbiology},
volume = {81},
number = {11},
pages = {370},
pmid = {39306818},
issn = {1432-0991},
support = {UMO-2019/03/X/NZ6/01710//Narodowym Centrum Nauki/ ; },
mesh = {*Pseudomonas aeruginosa/virology ; *Biofilms/growth & development ; *Pseudomonas Phages/physiology ; *Hydrophobic and Hydrophilic Interactions ; 1-Octanol/chemistry ; Myoviridae/physiology/chemistry ; Bacteriophages/physiology/chemistry ; },
abstract = {The bacteriophage F8 belongs to the Myoviridae group of phages and is a pathogen of Pseudomonas aeruginosa. Since Pseudomonas aeruginosa is a multidrug-resistant opportunistic bacterium and can cause serious challenges for health services, studying the potential use of phages against them is a promising approach. Pseudomonas aeruginosa can be found on medical devices because bacteria can attach to surfaces and develop biofilms, which are difficult to eradicate because of their high resistance to environmental conditions and antimicrobial therapeutics. Phage therapy is becoming promising as an alternative for the treatment of antibiotic-resistant infections, but there is still a lack of standardized protocols approved by health organizations for possible use in the clinic. In our research, we focused on the potential use of 1-octanol, which was previously used by our team to develop a method for phage purification from bacterial lysate. 1-octanol is a fatty alcohol that is mostly used in the cosmetics industry, and its advantage is that it is approved by the FDA as a food additive. In this paper, we studied the protective properties of the addition of 1-octanol for storing phage liquid preparations. We demonstrated the stabilization effect of 1-octanol addition on F8 bacteriophage preparation during storage under various conditions. Interestingly, more effective biofilm reduction was observed after treatment with the purified bacteriophage and with 1-octanol addition compared to crude lysate.},
}

*Pseudomonas aeruginosa/virology
*Biofilms/growth & development
*Pseudomonas Phages/physiology
*Hydrophobic and Hydrophilic Interactions
1-Octanol/chemistry
Myoviridae/physiology/chemistry
Bacteriophages/physiology/chemistry

@article {pmid39306312,
year = {2024},
author = {Javadi, K and Emadzadeh, MR and Mohammadzadeh Hosseini Moghri, SAH and Halaji, M and Parsian, H and Rajabnia, M and Pournajaf, A},
title = {Anti-biofilm and antibacterial effect of Bacteriocin derived from Lactobacillus plantarum on the multidrug-resistant Acinetobacter baumannii.},
journal = {Protein expression and purification},
volume = {},
number = {},
pages = {106610},
doi = {10.1016/j.pep.2024.106610},
pmid = {39306312},
issn = {1096-0279},
abstract = {This research examines the impact of bacteriocin derived from Lactobacillus plantarum PTCC 1745 on the biofilm formations of A. baumannii isolates. Bacteriocin derived from L. plantarum PTCC 1745 was obtained through ammonium sulfate precipitation, cation-exchange chromatography, and reversed-phase high-performance liquid chromatography (RP-HPLC). Testing for bacteriocin susceptibility has been conducted using the broth dilution method. The anti-biofilm activity of bacteriocin was evaluated using a microtiter plate method. Quantitative real-time PCR assay evaluated bap gene expression in bacteriocin-treated cells. According to SDS-PAGE, bacteriocin from L. plantarum has a 25-kDa apparent molecular weight. The MICs of bacteriocin ranged from 30 to 120 μg/mL, while the MBCs varied between 60 to 120 μg/mL. Compared to the non-treated group, strains bacteriocin-treated isolates had 59% less ability to form biofilm. The mean relative expression of the bap gene among the MDR A. baumannii isolates decreased by 52% compared to the untreated control. This study demonstrated that bacteriocin derived from L. plantarum PTCC 1745 had antibacterial and antibiofilm activity against MDR A. baumannii isolates.},
}

@article {pmid39305253,
year = {2024},
author = {Lalitha, MM and Banerjee, S and Jayaraj, A and Kamath, A and Divakaran, D and Yadav, V and Lakavathu, M and Sajimon, J and Anil, P and Shaijumon, MM and Singh, NS and Kurapati, R},
title = {Two-Dimensional Materials/Biopolymer-Based Antimicrobial Coatings to Thwart Biofilm Formation on Medical Implants.},
journal = {ACS applied bio materials},
volume = {},
number = {},
pages = {},
doi = {10.1021/acsabm.4c00725},
pmid = {39305253},
issn = {2576-6422},
abstract = {Infections associated with medical implants due to bacterial adhesion and biofilm formation are a serious problem, leading to acute health risks to patients by compromising their immune system. Therefore, suppressing biofilm formation on biomedical implants is a challenging task, especially for overcoming the drug resistance of bacterial biofilms. Herein, a synergistic efficient surface coating method was developed to inhibit biofilm formation on a model medical implant by combining the antimicrobial property of trimethyl chitosan (TMC) with either 2D material graphene oxide (GO) or black phosphorus (BP) sheets using layer-by-layer (LbL) self-assembly. The multilayer coatings of TMC/GO and TMC/BP were optimized on the glass surface (a model implant) and characterized by using spectroscopic and microscopy techniques. Next, we investigated the antibiofilm formation properties of the TMC/GO and TMC/BP coatings on glass surfaces against both Gram-negative, Escherichia coli (E. coli), and Gram-positive, Bacillus subtilis (B. subtilis), bacteria. The antibiofilm formation was studied using crystal violet (CV) and live/dead assays. Both the live/dead and the CV assays confirmed that the TMC/2D material (2DM)-coated surfaces prevented biofilm formation much more effectively compared to the uncoated surfaces. Scanning electron microscopy analyses revealed that the bacteria were affected physically by incubating with TMC/2DM-coated surfaces due to membrane perturbation, thereby preventing cell attachment and biofilm formation. Further, BP composite coatings (TMC/BP) showed a much better ability to thwart biofilm formation than GO composite coatings (TMC/GO). Also, multilayer coatings showed superior cytocompatibility with human foreskin fibroblast (HFF). Our results demonstrate that the developed coatings TMC/2DMs could be potential candidates for thwarting biofilm formation on medical implants.},
}

@article {pmid39304122,
year = {2024},
author = {Nguyen, HK and Duke, MM and Grayton, QE and Broberg, CA and Schoenfisch, MH},
title = {Impact of Nitric Oxide Donors on Capsule, Biofilm, and Resistance Profiles of Klebsiella pneumoniae.},
journal = {International journal of antimicrobial agents},
volume = {},
number = {},
pages = {107339},
doi = {10.1016/j.ijantimicag.2024.107339},
pmid = {39304122},
issn = {1872-7913},
abstract = {Klebsiella pneumoniae (K. pneumoniae) is a bacterial species currently considered a critical public health threat due to its ability to cause fatal, multidrug-resistant infections in the bloodstream and key organs. The polysaccharide-based capsule layer that shields K. pneumoniae from clearance via innate immunity is a prominent virulence factor. K. pneumoniae also forms biofilms on biotic and abiotic surfaces. These biofilms significantly reduce penetration by and antibacterial activity from traditional antibiotics. Nitric oxide (NO), an endogenous molecule involved in the innate immune system, is equally as effective at eradicating bacteria but without engendering resistance. Herein, we investigated the effects of NO-releasing small molecules capable of diverse release kinetics on the capsule and biofilm formation characteristics of multiple K. pneumoniae strains. The use of NO donors with moderate and extended NO-release properties (i.e., half-life >1.8 h) inhibited bacterial growth. Additionally, treatment with NO decreased the capsule mucoviscosity in K. pneumoniae strains that normally exhibit hypermucoviscous capsule. The NO donors were also effective against K. pneumoniae biofilms at the same minimum biocidal concentrations that eliminated planktonic bacteria, while meropenem showed little antibacterial action in the same experiments. These results represent the first account of exogenous NO affecting biomarkers involved in K. pneumoniae infections and may therefore inform future development of NO-based therapeutics for treating such infections.},
}

@article {pmid39303497,
year = {2024},
author = {Lou, X and Wu, Y and Chen, Z and Zhang, Q and Xiao, X and Fang, Z},
title = {Novel insights into biofilm formation and the key differentially expressed genes in Yersinia enterocolitica from meat: Implications for food safety and disease prevention.},
journal = {International journal of food microbiology},
volume = {426},
number = {},
pages = {110914},
doi = {10.1016/j.ijfoodmicro.2024.110914},
pmid = {39303497},
issn = {1879-3460},
abstract = {Yersinia enterocolitica is an important foodborne pathogen that can cause a zoonotic disease known as yersiniosis, which causes symptoms such as acute diarrhea, mesenteric adenitis, terminal ileum inflammation, pseudo appendicitis, sepsis, and other complications. The mechanism of biofilm formation in Y. enterocolitica remains poorly understood, with limited research available on this topic. This study systematically examined the distribution characteristics and biofilm formation ability of Y. enterocolitica isolated from poultry and livestock related samples. Analysis of food samples collected indicated significant presence of Y. enterocolitica (207/670, 30.9 %), particularly in frozen duck meat (7/11, 63.6 %). Majority of the isolated strains did not demonstrate biofilm-forming ability (52.7 %), while a notable percentage exhibited moderate (6.8 %) to strong (11.6 %) biofilm-forming ability. Additionally, a significant percentage of strains (16/207, 7.7 %) displayed extremely high optical density/cut-off OD (OD/ODC) ratios (the average OD value of each sample divided by the average OD value of the negative controls of each 96-well plate plus 3 standard deviations) (exceeding 10). Time-course analysis of biofilm formation in 10 isolates revealed three distinct patterns: (i) rapid increase from 6 h to 12 h, with gradual peak between 48 and 72 h followed by a slight decline and stabilization; (ii) little biofilm formation at 24 h with a gradual increase up to 96 h, maintaining this level until 120 h; and (iii) complete absence of biofilm formation throughout the experiment. Subsequent examination of differentially expressed genes (DEGs) in planktonic cells and biofilms of two strains with distinct biofilm formation capabilities identified seven metabolic pathways, including ribosome, photosynthesis, fatty acid degradation, valine, leucine, and isoleucine degradation, as well as pinene, camphor, and geraniol degradation. Significantly elevated expression levels of genes associated with flagellar assembly, bacterial chemotaxis, and quorum sensing (partially) were observed exclusively in planktonic cells of the selected strain with stronger biofilm-forming ability, implying that the heightened expression of flagellar assembly and bacterial chemotaxis-related genes is an important but not sole determinant of biofilm formation. The study contributes to the elucidation of the underlying mechanisms governing biofilm formation in Y. enterocolitica and may offer valuable insights for the advancement of novel food safety strategies.},
}

@article {pmid39302957,
year = {2024},
author = {Ramos, RCPDS and de Oliveira, NS and Bianchini, LF and Azevedo-Alanis, LR and Pimentel, IC and Hardy, AMTG and Murata, RM and Glassey, J and Rosa, EAR},
title = {Cunninghamella echinulata DSM1905 biofilm-based L-asparaginase production in pneumatically-driven bioreactors.},
journal = {PloS one},
volume = {19},
number = {9},
pages = {e0308847},
pmid = {39302957},
issn = {1932-6203},
mesh = {*Bioreactors/microbiology ; *Cunninghamella/metabolism ; *Biofilms/growth & development ; *Asparaginase/biosynthesis/metabolism ; Fermentation ; Biomass ; },
abstract = {We evaluated by comparing the performance of three pneumatically-driven bioreactors in the production of L-asparaginase (L-ASNase), an enzyme used to treat leukaemia and lymphoma. A two-step screening process was conducted to detect Cunninghamella spp. strains producing L-ASNase. Cunninghamella echinulata DSM1905 produced the highest levels of L-ASNase during screening assays. Subsequently, fermentations were performed in bubble column (BCR), airlift (ALR), and hybrid fixed-bed airlift (FB-ALR) bioreactors to determine the best upstream bioprocess. Mycelial biomass production was higher in BCR than in ALR and FB-ALR (p ≤ 0.0322). The activity of L-ASNase produced in FB-ALR, in which the fungus grew as a consistent biofilm, was significantly higher (p ≤ 0.022) than that from ALR, which was higher than that of BCR (p = 0.036). The specific activity of ALR and FB-ALR presented no differences (p = 0.073), but it was higher than that of BCR (p ≤ 0.032). In conclusion, C. echinulata DSM1905, grown under the biofilm phenotype, produced the highest levels of L-ASNase, and FB-ALR was the best upstream system for enzyme production.},
}

*Bioreactors/microbiology
*Cunninghamella/metabolism
*Biofilms/growth & development
*Asparaginase/biosynthesis/metabolism
Fermentation
Biomass

@article {pmid39300947,
year = {2024},
author = {Zeb, BS and Mahmood, Q and Irshad, M and Zafar, H and Wang, R},
title = {Sustainable treatment of combined industrial wastewater: synergistic phytoremediation with Eichhornia crassipes, Pistia stratiotes, and Arundo donax in biofilm wetlands.},
journal = {International journal of phytoremediation},
volume = {},
number = {},
pages = {1-7},
doi = {10.1080/15226514.2024.2403037},
pmid = {39300947},
issn = {1549-7879},
abstract = {This study investigates the treatment of combined wastewater from Hattar Industrial Estate using Biofilm Wetlands (BW) planted with monoculture species: Eichhornia crassipes (EAC), Pistia stratiotes (WL), and Arundo donax (GR). Each species showed distinct capabilities in organic degradation, metal uptake, and pH stabilization. BW2, planted with EAC, achieved the highest total solids (TS) and total suspended solids (TSS) removal efficiencies of 66% and 65%, respectively. GR effectively reduced initial COD concentrations from 232 mg/L to 58.67 mg/L, while EAC and WL reached reductions to 72.78 mg/L and 70.67 mg/L, respectively. Overall, the plant efficiency ranking was EAC > GR > WL. These findings underscore the potential of these plant species in synergistic BW systems, highlighting their role as natural solutions for remediating complex industrial effluents. This research contributes to advancing eco-friendly wastewater treatment approaches, suggesting promising applications for sustainable practices in industrial contexts.RESEARCH HIGHLIGHTSThis research assessed the effectiveness of phytoremediation using Eichhornia crassipes, Pistia stratiotes, and Arundo donax for removing pollutants i.e. heavy metals (Cd, Pb, Ni, K, Ca, Mg, Na, Fe, Hg) nitrates, phosphates and sulfates from combined industrial wastewater of Hattar Industrial Estate Pakistan.It highlighted the potential of selected plant species' as natural treatment systems, providing crucial insights into their efficiency.Findings contribute to understanding nature-based solutions for complex industrial effluents.},
}