@article {pmid39393325,
year = {2024},
author = {Yang, C and Huang, B and Lin, J and Yang, Q and Guo, Y and Liu, D and Sun, B},
title = {Isolation and screening of high biofilm producing lactic acid bacteria, and exploration of its effects on the microbial hazard in corn straw silage.},
journal = {Journal of hazardous materials},
volume = {480},
number = {},
pages = {136009},
doi = {10.1016/j.jhazmat.2024.136009},
pmid = {39393325},
issn = {1873-3336},
abstract = {Silage is a well-established method for preserving feed. However, the preparation process still poses several potential microbial hazards. Lactic acid bacteria exhibiting a biofilm phenotype are considered the most advanced 'fourth-generation probiotics' due to their significant potential in enhancing fermentation quality. In this study, a strain of high-biofilm-producing lactic acid bacteria (HBP-LAB) was successfully isolated from silage samples using the crystal violet method and designated as Lactiplantibacillus plantarum S23Y. This strain was subsequently used as an inoculant in corn straw for experimental purposes. The results indicated that it effectively reduced dry matter loss caused by microorganisms, thereby enhancing the retention of dry matter in silage. Following aerobic exposure, this strain was able to maintain the population of Lactobacillus and the concentration of lactic acid, which significantly decreased the likelihood of yeast-induced aerobic spoilage and improved the aerobic stability of the silage. However, it is important to note that this HBP-LAB did not have a significant impact on antibiotic resistance genes (ARGs) or mobile genetic elements (MGEs) in the silage. In conclusion, using S23Y as a representative strain, we have demonstrated that HBP-LAB can enhance the fermentation quality of silage to a certain extent and mitigate the detrimental effects of microorganisms. The findings of this study provide valuable insights for the application of lactic acid bacteria with a biofilm phenotype in silage fermentation.},
}

@article {pmid39392011,
year = {2024},
author = {Javanmard, Z and Pourhajibagher, M and Bahador, A},
title = {Advancing Anti-Biofilm Strategies: Innovations to Combat Biofilm-Related Challenges and Enhance Efficacy.},
journal = {Journal of basic microbiology},
volume = {},
number = {},
pages = {e2400271},
doi = {10.1002/jobm.202400271},
pmid = {39392011},
issn = {1521-4028},
abstract = {Biofilms are complex communities of microorganisms that can cause significant challenges in various settings, including industrial processes, environmental systems, and human health. The protective nature of biofilms makes them resistant to traditional anti-biofilm strategies, such as chemical agents, mechanical interventions, and surface modifications. To address the limitations of conventional anti-biofilm methods, researchers have explored emerging strategies that encompass the use of natural compounds, nanotechnology-based methods, quorum-sensing inhibition, enzymatic degradation, and antimicrobial photodynamic/sonodynamic therapy. There is an increasing focus on combining multiple anti-biofilm strategies to combat resistance and enhance effectiveness. Researchers are continuously investigating the mechanisms of biofilm formation and developing innovative approaches to overcome the limitations of conventional anti-biofilm methods. These efforts aim to improve the management of biofilms and prevent infections while preserving the environment. This study provides a comprehensive overview of the latest advancements in anti-biofilm strategies. Given the dynamic nature of this field, exploring new approaches is essential to stimulate further research and development initiatives. The effective management of biofilms is crucial for maintaining the health of industrial processes, environmental systems, and human populations.},
}

@article {pmid39391921,
year = {2024},
author = {Samoilova, Z and Smirnova, G and Sutormina, L and Oktyabrsky, O},
title = {Modulating effects of fodder grasses extracts on antibiotic sensitivity and biofilm production in avian pathogenic Escherichia coli strains.},
journal = {Biofouling},
volume = {},
number = {},
pages = {1-15},
doi = {10.1080/08927014.2024.2414222},
pmid = {39391921},
issn = {1029-2454},
abstract = {Extracts of certain fodder grasses may be viewed as powerful agents against infections induced by avian pathogenic Escherichia coli strains. Here we demonstrated ability of Galega orientalis and Rhaponticum carthamoides extracts, alone or in combination with antibiotics, to inhibit growth, viability and biofilm formation in avian pathogenic Escherichia coli strains with different sensitivity to antibiotics and non-pathogenic laboratory strain E. coli BW25113 as well as its mutant derivatives. Modulation of motility and production of extracellular structures in the presence of the extracts correlated with their anti-biofilm effects. Interestingly, an increase in antibacterial action of kanamycin, streptomycin, ciprofloxacin, and cefotaxime on both biofilms and planktonic cultures of the studied strains was observed in the presence of the extracts, including antibiotic resistant APEC strain #45. The extracts alone showed weak prooxidant activity which could contribute to modification of redox-sensitive sites of various regulatory circuits, resulting to synergetic effects in combination with antibiotics.},
}

@article {pmid39386371,
year = {2024},
author = {Salazar, M and Shahbazi Nia, S and German, NA and Awosile, B and Sabiu, S and Calle, A},
title = {Exploring diflunisal as a synergistic agent against Staphylococcus aureus biofilm formation.},
journal = {Frontiers in microbiology},
volume = {15},
number = {},
pages = {1399996},
pmid = {39386371},
issn = {1664-302X},
abstract = {Staphylococcus aureus is a bacterial pathogen of considerable significance in public health, capable of inducing a diverse range of infectious diseases. One of the most notorious mechanisms used by S. aureus to survive and colonize the site of infection is its ability to form biofilms. Diflunisal, a non-steroidal anti-inflammatory drug (NSAID), is a known inhibitor of the Agr system in S. aureus, which is key in regulating biofilm formation. This study evaluated the effect of broad-spectrum antibiotics in combination with diflunisal on S. aureus biofilm density. Eight antibiotics were tested independently at different concentrations and in combination with diflunisal to assess their effect on S. aureus biofilm formation. When using the antibiotics alone and with diflunisal, a significant control effect on biofilm formation was observed (p < 0.05), irrespective of diflunisal presence, but did not achieve a complete biofilm growth inhibition. Over time, diflunisal influenced biofilm formation; however, such an effect was correlated with antibiotic concentration and exposure time. With amikacin treatments, biofilm density increased with extended exposure time. In the case of imipenem, doripenem, levofloxacin, and ciprofloxacin, lower doses and absence of diflunisal showed higher control over biofilm growth with longer exposure. However, in all cases, diflunisal did not significantly affect the treatment effect on biofilm formation. In the absence of antibiotics, diflunisal significantly reduced biofilm formation by 53.12% (p < 0.05). This study suggests that diflunisal could be a potential treatment to control S. aureus biofilms, but it does not enhance biofilm inhibition when combined with antibiotics.},
}

@article {pmid39385119,
year = {2024},
author = {Rizkinata, D and Waturangi, DE and Yulandi, A},
title = {Synergistic action of bacteriophage and metabolites of Pseudomonas fluorescens JB3B and Streptomyces thermocarboxydus 18PM against Enterotoxigenic Escherichia coli and Bacillus cereus and their biofilm.},
journal = {BMC microbiology},
volume = {24},
number = {1},
pages = {398},
pmid = {39385119},
issn = {1471-2180},
mesh = {*Biofilms/drug effects/growth & development ; *Bacillus cereus/drug effects/virology ; *Pseudomonas fluorescens/virology/drug effects ; *Streptomyces/virology/physiology ; *Enterotoxigenic Escherichia coli/drug effects/physiology ; *Bacteriophages/physiology ; Anti-Bacterial Agents/pharmacology ; Food Microbiology ; },
abstract = {BACKGROUND: Foodborne disease and food spoilage are the prime public health issue and food security round the globe. Significant disease outbreaks mostly linked to the existence of pathogenic bacteria that extremely challenging due to the persistence of biofilm-forming. Proteins and bacterial metabolites have been shown to have good antibacterial activity and effectively removal bacterial biofilm. Recently, bacteriophage and their encoded lytic proteins such as lysin have attracted attention as potential alternative agent to control undesirable pathogens in human body infection, increasing food safety as advance preservations and medical treatment such as phage therapy. For these reasons, the efficacy of bacteriophage and their potential in combination with bacterial metabolites from Phyllosphere and Actinomycetes bacteria (Pseudomonas fluorescens JB3B and Streptomyces thermocarboxydus 18PM crude extracts) was the aim of this present study.

RESULTS: In this study, bacteriophage BC-VP (1.28 ± 0.29 × 10[11] PFU/ml) and ETEC-phage-TG (8.9 ± 2.19 × 10[8] PFU/ml) isolated from artificial lake water from previous study showed potential activity to control Bacillus cereus (BC) and Enterotoxigenic Escherichia coli (ETEC) population. The combination of BC-VP with metabolite (P. fluorescens JB3B and S. thermocarboxydus 18PM) which were known from previous study had antibiofilm activities were able to inhibit (86.1%; 83.3%) and destruct (41%; 45.5%) biofilm formation of B. cereus respectively. Likewise, the synergy of bacteriophage ETEC-phage-TG with the same crude extract also showed promising activity against biofilm of ETEC with percentage of inhibition (81.9%; 76.4%) and percentage of destruction (54.1%; 44.4%). Application in various food, combination of BC-VP and bacterial metabolite extract (P. fluorescens JB3B; S. thermocarboxydus 18PM) were able to reduce Bacillus cereus population in mashed potato (99.6%; 99.4%) at cold temperature (4 °C) and (68.9%; 56.6%) at room temperature (28 °C), boiled pasta (99.5%; 99.4%) and (84.7%; 75.7%), also soymilk (96.9%; 96.7%) and (42.4%; 39.4%) respectively. Likewise, combination of ETEC-phage-TG and bacterial metabolite (P. fluorescens JB3B; S. thermocarboxydus 18PM) potentially reduced ETEC population after two different temperatures (4 °C and 28 °C) incubation in bean sprouts (TFTC; TFTC) and (47.5%; 49.1%), chicken meat (TFTC; TFTC) and (58.1%; 54%), also minced beef (99.5%; 99.4%) and (41.1%; 28%). GC-MS determination performed, oxalic acid, phenol, phenylethyl alcohol, N-hexadecanoic acid, and pyrolol[1,2-a]pyrazine-1,4-dione, hexadro-3-92-methylpropyl was the most active compound in P. fluorescens JB3B. 2,4-Di-tert-butylphenol, phenyl acetic acid, N-Hexadecanoic acid, pyrolol[1,2-a]pyrazine-1,4-dione, hexadro-3-92-methylpropyl, and Bis(2-ethylhexyl) phthalate was most active compound in the S. thermocarboxydus 18PM isolates.

CONCLUSIONS: The combination of isolated bacteriophages and bacterial metabolite showed promising results to be used as biocontrol candidate to overcome biofilm formed by foodborne and food spoilage bacteria using their ability to produce antibiofilm compounds and lytic activity. In addition, this combination also potentially reduces the use or replace the drawbacks of common application such as antibiotic treatment.},
}

*Biofilms/drug effects/growth & development
*Bacillus cereus/drug effects/virology
*Pseudomonas fluorescens/virology/drug effects
*Streptomyces/virology/physiology
*Enterotoxigenic Escherichia coli/drug effects/physiology
*Bacteriophages/physiology
Anti-Bacterial Agents/pharmacology
Food Microbiology

@article {pmid39384943,
year = {2024},
author = {Du, X and Li, P and Fan, C and Tian, J and Lin, Y and Xie, J and Cheng, J and Fu, Y and Jiang, D and Yuan, M and Yu, X and Tsuda, K and Li, B},
title = {Holliday junction resolvase RuvC targets biofilm eDNA and confers plant resistance to vascular pathogens.},
journal = {Nature plants},
volume = {},
number = {},
pages = {},
pmid = {39384943},
issn = {2055-0278},
support = {32272556//National Natural Science Foundation of China (National Science Foundation of China)/ ; },
abstract = {A biofilm lifestyle is critical for bacterial pathogens to colonize and protect themselves from host immunity and antimicrobial chemicals in plants and animals. The formation and regulation mechanisms of phytobacterial biofilm are still obscure. Here we found that the protein Ralstonia solanacearum resistance to ultraviolet C (RuvC) is highly abundant in biofilm and positively regulates pathogenicity by controlling systemic movement in tomato xylem. RuvC protein accumulates at the later stage of biofilm development and specifically targets Holliday junction (HJ)-like structures to disrupt the biofilm extracellular DNA (eDNA) lattice, thus facilitating biofilm dispersal. Recombinant RuvC protein can resolve extracellular HJ to prevent bacterial biofilm formation. Heterologous expression of R. solanacearum or Xanthomonas oryzae pv. oryzae RuvC with plant secretion signal in tomato or rice confers resistance to bacterial wilt or bacterial blight disease, respectively. Plant chloroplast-localized HJ resolvase monokaryotic chloroplast 1 (MOC1), which shares structural similarity with bacterial RuvC, shows a strong inhibitory effect on bacterial biofilm formation. Relocalization of SlMOC1 to apoplast in tomato roots leads to increased resistance to bacterial wilt. Our novel finding reveals a critical pathogenesis mechanism of R. solanacearum and provides an efficient biotechnology strategy to improve plant resistance to bacterial vascular disease.},
}

@article {pmid39384811,
year = {2024},
author = {Devanga Ragupathi, NK and Muthuirulandi Sethuvel, DP and Ganesan, A and Murugan, D and Baskaran, A and Wannigama, DL and Monk, PN and Karunakaran, E and Veeraraghavan, B},
title = {Evaluation of mrkD, pgaC and wcaJ as biomarkers for rapid identification of K. pneumoniae biofilm infections from endotracheal aspirates and bronchoalveolar lavage.},
journal = {Scientific reports},
volume = {14},
number = {1},
pages = {23572},
pmid = {39384811},
issn = {2045-2322},
support = {10065043//QR GCRF , UKRI/ ; GCRFNGR5\1293//Academy of Medical Sciences, UK/ ; },
mesh = {*Biofilms/growth & development ; *Klebsiella pneumoniae/genetics/isolation & purification ; Humans ; *Klebsiella Infections/microbiology/diagnosis ; *Biomarkers ; Bronchoalveolar Lavage Fluid/microbiology ; Bacterial Proteins/genetics ; },
abstract = {Klebsiella pneumoniae has been identified as one of the most important opportunistic pathogens responsible for nosocomial infections. Antibiotic resistance and the ability to form biofilms are the two main factors involved in the persistence of infections. Conventional detection methods involve culture isolation and identification followed by biofilm assay that takes 48-72 h. Timely detection of biofilm-forming resistant pathogens is essential to appropriately treat the infection with the right dose and combinations. The present study focuses on evaluating an RT-PCR panel using mrkD, pgaC, and wcaJ genes to screen for biofilm-forming K. pneumoniae from ETA/BAL specimens. The assay accurately identified K. pneumoniae harboring samples with a limit of detection of 1 ng/µl total RNA. Representative culture-negative-PCR-positive samples were subjected to metagenomics which identified K. pneumoniae reads in these samples confirming the specificity of RT-PCR. mrkD and pgaC act as K. pneumoniae specific identification whereas wcaJ acts as a negative marker for biofilm-forming K. pneumoniae. In addition, RT-PCR results correlated well with the phenotypic biofilm-forming assay. This RT-PCR assay is the first of its kind for rapid identification of biofilm-forming K. pneumoniae. The result of this study highlights that the rapid detection of K. pneumoniae biofilms based on the RT-PCR results coupled with clinical conditions would be appropriate to treat emerging infections or to prevent re-infections in clinical settings.},
}

*Biofilms/growth & development
*Klebsiella pneumoniae/genetics/isolation & purification
Humans
*Klebsiella Infections/microbiology/diagnosis
*Biomarkers
Bronchoalveolar Lavage Fluid/microbiology
Bacterial Proteins/genetics

@article {pmid39384621,
year = {2024},
author = {Pal, S and Chatterjee, N and Sinha Roy, S and Chattopadhyay, B and Acharya, K and Datta, S and Dhar, P},
title = {Valorization of oil refinery by-products: production of sophorolipids utilizing fatty acid distillates and their potential antibacterial, anti-biofilm, and antifungal activities.},
journal = {World journal of microbiology & biotechnology},
volume = {40},
number = {11},
pages = {344},
pmid = {39384621},
issn = {1573-0972},
support = {1626/(NET-DEC2018)//University Grants Commission/ ; },
mesh = {*Biofilms/drug effects ; *Antifungal Agents/pharmacology/metabolism ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology/biosynthesis ; *Plant Oils/pharmacology/metabolism/chemistry ; *Fatty Acids ; Bacteria/drug effects ; Surface-Active Agents/pharmacology/metabolism ; Palm Oil/chemistry/pharmacology ; Sunflower Oil/chemistry ; Saccharomycetales/metabolism ; Fungi/drug effects ; Soybean Oil/metabolism/pharmacology ; Oleic Acids ; },
abstract = {Starmerella bombicola is a native yeast strain producing sophorolipids as secondary metabolites. This study explores the production, characterization, and biological activities of sophorolipids and investigates the antimicrobial, anti-biofilm, and antifungal properties of sophorolipids produced from oil refinery wastes by the yeast Starmerella bombicola. The present work demonstrated that S. bombicola MTCC 1910 when grown in oil refinery wastes namely palm fatty acid distillates and soy fatty acid distillates enhanced the rate of sophorolipids production drastically in comparison to vegetable oil, sunflower oil used as hydrophobic feedstock. Sophorolipid yields were 18.14, 37.21, and 46.1 g/L with sunflower oil, palm, and soy fatty acid distillates respectively. The crude biosurfactants were characterized using TLC, FTIR, and HPLC revealing to be acetylated sophorolipids containing both the acidic and lactonic isomeric forms. The surface lowering and emulsifying properties of the sophorolipids from refinery wastes were significantly higher than the sunflower oil-derived sophorolipids. Also, all the sophorolipids exhibited strong antibacterial properties (minimum inhibitory concentrations were between 50 and 200 µg mL[-1]) against Salmonella typhimurium, Bacillus cereus, and Staphylococcus epidermidis and were validated with morphological analysis by Scanning electron microscopy. All the sophorolipids were potent biofilm inhibitors and eradicators (minimum biofilm inhibitory and eradication concentrations were between 12.5 to 1000 µg mL[-1]) for all the tested organisms. Furthermore, antifungal activities were also found to exhibit about 16-56% inhibition at 1 mg mL[-1] for fungal mycelial growth. Therefore, this endeavour of sophorolipids production using palm and soy fatty acid distillates not only opens up a window for the bioconversion of industrial wastes into productive biosurfactants but also concludes that sophorolipids from oil refinery wastes are potent antimicrobial, anti-biofilm, and antifungal agents, highlighting their potential in biotechnological and medical applications.},
}

*Biofilms/drug effects
*Antifungal Agents/pharmacology/metabolism
*Microbial Sensitivity Tests
*Anti-Bacterial Agents/pharmacology/biosynthesis
*Plant Oils/pharmacology/metabolism/chemistry
*Fatty Acids
Bacteria/drug effects
Surface-Active Agents/pharmacology/metabolism
Palm Oil/chemistry/pharmacology
Sunflower Oil/chemistry
Saccharomycetales/metabolism
Fungi/drug effects
Soybean Oil/metabolism/pharmacology
Oleic Acids

@article {pmid39384180,
year = {2024},
author = {Milli, G and Pellegrini, A and Listro, R and Fasolini, M and Pagano, K and Ragona, L and Pietrocola, G and Linciano, P and Collina, S},
title = {New LsrK Ligands as AI-2 Quorum Sensing Interfering Compounds against Biofilm Formation.},
journal = {Journal of medicinal chemistry},
volume = {},
number = {},
pages = {},
doi = {10.1021/acs.jmedchem.4c01266},
pmid = {39384180},
issn = {1520-4804},
abstract = {Antimicrobial resistance (AMR) represents a critical global health crisis. An innovative strategy to deal with AMR is to interfere with biofilm formation and bacterial quorum sensing (QS). In this study, newly designed autoinducer-2 (AI-2)-inspired compounds in targeting biofilm-associated infections were evaluated for their ability to inhibit biofilm formation in Staphylococcus aureus and Pseudomonas aeruginosa. The most effective compounds, 5d, 5e, and 7b, exhibited potent antibiofilm activity with minimal inhibitory concentrations in the low microgram per mL range. Detailed biological assays confirmed that the antibiofilm activity was primarily driven through AI-2 QS inhibition rather than direct antimicrobial effects. The combination of different spectroscopic techniques, such as differential scanning fluorimetry, intrinsic tryptophan fluorescence, circular dichroism, and nuclear magnetic resonance, elucidated the binding between the compounds and the LsrK enzyme, a key player in AI-2 mediated QS. Our findings highlight the potential of these novel QS inhibitors as promising therapeutic agents against biofilm-associated infections.},
}

@article {pmid39384150,
year = {2024},
author = {Wang, L and Tkhilaishvili, T and Jiang, Z and Pirlar, RF and Ning, Y and Laleona, AM and Wang, J and Tang, J and Wang, Q and Trampuz, A and Moreno, MG and Zhang, X},
title = {Phage-liposome nanoconjugates for orthopedic biofilm eradication.},
journal = {Journal of controlled release : official journal of the Controlled Release Society},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.jconrel.2024.09.049},
pmid = {39384150},
issn = {1873-4995},
abstract = {Infection by multidrug-resistant (MDR) bacteria has become one of the biggest threats to public health worldwide. One reason for the difficulty in treatment is the lack of proper delivery strategies into MDR bacterial biofilms, where the thick extracellular polymeric substance (EPS) layer impedes the penetration of antibiotics and nanoparticles. Here, we propose a novel bioactive nanoconjugate of drug-loaded liposomes and bacteriophages for targeted eradication of the MDR biofilms in orthopedic infections. Phage Sb-1, which has the ability to degrade EPS, was conjugated with antibiotic-loaded liposomes. Upon encountering the biofilm, phage Sb-1 degrades the EPS structure, thereby increasing the sensitivity of bacteria to antibiotics and allowing the antibiotics to penetrate deeply into the biofilm. As a result, effective removal of MDR bacterial biofilm was achieved with low dose of antibiotics, which was proved in this study by both in vitro and in vivo investigations. Notably, in the rat prosthetic joint infection (PJI) model, we found that the liposome-phage nanoconjugates could effectively decrease the bacterial load in the infected area and significantly promote osteomyelitis recovery. It is therefore believed that the conjugation of bacteriophage and liposomes could open new possibilities for the treatment of orthopedic infections, possibly other infections in the deep tissues.},
}

@article {pmid39384023,
year = {2024},
author = {Thamayandhi, C and El-Tayeb, MA and Syed, SR and Sivaramakrishnan, R and Gunasekar, B},
title = {Antibacterial and anti-biofilm efficacy of selenium nanoparticles against Pseudomonas aeruginosa: Characterization and in vitro analysis.},
journal = {Microbial pathogenesis},
volume = {},
number = {},
pages = {106998},
doi = {10.1016/j.micpath.2024.106998},
pmid = {39384023},
issn = {1096-1208},
abstract = {Pseudomonas aeruginosa (P. aeruginosa), a Gram-negative opportunistic pathogen, poses significant treatment challenges due to its antibiotic resistance and biofilm formation. This study investigates the anti-bacterial and anti-biofilm activities of chemically synthesized selenium nanoparticles (SeNPs) against P. aeruginosa. SeNPs were synthesized using ascorbic acid as a reducing agent and characterized. Biofilm formation was quantified using a modified microtiter plate method, and the anti-biofilm efficacy of SeNPs was evaluated using confocal microscopy and SEM. The P.aeruginosa isolates exhibited high resistance to piperacillin-tazobactam (60%) and ceftazidime (59%). SeNPs demonstrated a round shape with a diameter of 15-18 nm. UV-Vis spectra showed a peak at 275 nm, and XRD analysis revealed crystalline peaks corresponding to selenium. The FTIR spectra confirmed the presence of various functional groups. SeNPs significantly reduced biofilm formation in a dose-dependent manner, with MIC50 and MIC90 values of 60 μg/mL and 80 μg/mL, respectively. Confocal microscopy and SEM analysis showed a notable decrease in biofilm thickness and bacterial adherence post-SeNPs treatment. These findings suggest that SeNPs could be a promising alternative or adjunctive treatment option for combating antibiotic-resistant P. aeruginosa infections. Further research is warranted to explore the clinical applications of SeNPs in treating biofilm-associated infections.},
}

@article {pmid39383826,
year = {2024},
author = {Wang, D and Wen, S and Liu, H and Liu, P and Xiong, J and Wu, Y and Li, Z and Tian, Z and Liu, B and Xu, D and Gu, T and Wang, F},
title = {Mitigation of biocorrosion of X80 carbon steel by a shale microbiome biofilm using a green biocide enhanced by d-amino acids.},
journal = {Bioelectrochemistry (Amsterdam, Netherlands)},
volume = {161},
number = {},
pages = {108831},
doi = {10.1016/j.bioelechem.2024.108831},
pmid = {39383826},
issn = {1878-562X},
abstract = {Microbiologically influenced corrosion (MIC) in shale gas field is a major threat with the hydraulic fracturing fluid injected into the subsurface. In this study, the microbiome collected from a shale gas produced water sample was extracted and cultivated in ATCC 1249 medium modified with 10 g/L NaCl anaerobically at 30 °C. d-amino acids, which were reported as biocide enhancers, were found to enhance 2,2-dibromo-3-nitrilopropionamide (DBNPA) biocide on the mitigation of shale microbiome MIC on X80 carbon steel. The combination of 50 ppm (w/w) d-leucine + 50 ppm d-alanine + 1 ppm d-tyrosine had the best enhancement effect on 50 ppm DBNPA with 84 % less weight loss, and 67 % lower corrosion current density (icorr) compared to 50 ppm DBNPA alone. The corrosion data were consistent with the enhanced biofilm inhibition observation. The experimental data also indicated that d-tyrosine used alone at a low dosage of 1 ppm enhanced DBNPA considerably, with 44 % less weight loss and 47 % less icorr. The electrochemical results showed the positive response of shale gas microbiome biofilm to the injected magnetite nanoparticles indicating the extracellular electron transfer might be a main mechanism for its corrosion.},
}

@article {pmid39383754,
year = {2024},
author = {Wu, Y and Sun, Q and Zhou, Z and Wang, Z and Fu, H},
title = {Efficient degradation of carbamazepine and metagenomic investigations of anodic biofilm in microbial fuel cells.},
journal = {Journal of environmental management},
volume = {370},
number = {},
pages = {122743},
doi = {10.1016/j.jenvman.2024.122743},
pmid = {39383754},
issn = {1095-8630},
abstract = {Environmental contamination with carbamazepine is a considerable global problem. In this study, two-compartment microbial fuel cells (MFCs) were constructed to investigate the degradation performance of carbamazepine, and the degradation mechanism was further explored by using metagenomic analysis. The results showed that MFCs exhibited excellent carbamazepine removal performance and also generated electricity. The removal rate of carbamazepine reached 73.56% over the 72-h operation period, which was 3.09 times higher than that of the traditional anaerobic method, and the peak voltage of the MFCs could reach 416 mV. Metagenomics revealed significant differences in microbial community composition between MFCs and the traditional anaerobic method (p < 0.05), and Proteobacteria (81.57%) was predominant bacterial phyla during the degradation of carbamazepine by MFCs. Among them, the microbial communities at the genus level were mainly composed of Pseudomonas, Pusillimonas, Burkholderia, Stenotrophomonas, Methyloversatilis and Nitrospirillum. Kyoto Encyclopedia of genes and genomes (KEGG) metabolic pathway analysis showed that the number of genes related to carbon and nitrogen metabolism increased by 85.12% and 142.25%, respectively. Importantly, a greater number of genes of microbial grown on the surface of anode were assigned to denitrification and the degradation of aromatic compounds. This research provides a cost-effective method for treating wastewater contaminated with carbamazepin.},
}

@article {pmid39383746,
year = {2024},
author = {Das, S and Pradhan, T and Panda, SK and Behera, AD and Kumari, S and Mallick, S},
title = {Bacterial biofilm-mediated environmental remediation: Navigating strategies to attain Sustainable Development Goals.},
journal = {Journal of environmental management},
volume = {370},
number = {},
pages = {122745},
doi = {10.1016/j.jenvman.2024.122745},
pmid = {39383746},
issn = {1095-8630},
abstract = {Bacterial biofilm is a structured bacterial community enclosed within a three-dimensional polymeric matrix, governed by complex signaling pathways, including two-component systems, quorum sensing, and c-di-GMP, which regulate its development and resistance in challenging environments. The genetic configurations within biofilm empower bacteria to exhibit significant pollutant remediation abilities, offering a promising strategy to tackle diverse ecological challenges and expedite progress toward Sustainable Development Goals (SDGs). Biofilm-based technologies offer advantages such as high treatment efficiency, cost-effectiveness, and sustainability compared to conventional methods. They significantly contribute to agricultural improvement, soil fertility, nutrient cycling, and carbon sequestration, thereby supporting SDG 1 (No poverty), SDG 2 (Zero hunger), SDG 13 (Climate action), and SDG 15 (Life on land). In addition, biofilm facilitates the degradation of organic-inorganic pollutants from contaminated environments, aligning with SDG 6 (Clean water and sanitation) and SDG 14 (Life below water). Bacterial biofilm also has potential applications in industrial innovation, aligning SDG 7 (Affordable and clean energy), SDG 8 (Decent work and economic growth), and SDG 9 (Industry, innovation, and infrastructure). Besides, bacterial biofilm prevents several diseases, aligning with SDG 3 (Good health and well-being). Thus, bacterial biofilm-mediated remediation provides advanced opportunities for addressing environmental issues and progressing toward achieving the SDGs. This review explores the potential of bacterial biofilms in addressing soil pollution, wastewater, air quality improvement, and biodiversity conservation, emphasizing their critical role in promoting sustainable development.},
}

@article {pmid39381779,
year = {2024},
author = {Sivori, F and Cavallo, I and Truglio, M and De Maio, F and Sanguinetti, M and Fabrizio, G and Licursi, V and Francalancia, M and Fraticelli, F and La Greca, I and Lucantoni, F and Camera, E and Mariano, M and Ascenzioni, F and Cristaudo, A and Pimpinelli, F and Di Domenico, EG},
title = {Staphylococcus aureus colonizing the skin microbiota of adults with severe atopic dermatitis exhibits genomic diversity and convergence in biofilm traits.},
journal = {Biofilm},
volume = {8},
number = {},
pages = {100222},
pmid = {39381779},
issn = {2590-2075},
abstract = {Atopic dermatitis (AD) is a chronic inflammatory skin disorder exacerbated by Staphylococcus aureus colonization. The specific factors that drive S. aureus overgrowth and persistence in AD remain poorly understood. This study analyzed skin barrier functions and microbiome diversity in lesional (LE) and non-lesional (NL) forearm sites of individuals with severe AD compared to healthy control subjects (HS). Notable differences were found in transepidermal water loss, stratum corneum hydration, and microbiome composition. Cutibacterium was more prevalent in HS, while S. aureus and S. lugdunensis were predominantly found in AD LE skin. The results highlighted that microbial balance depends on inter-species competition. Specifically, network analysis at the genus level demonstrated that overall bacterial correlations were higher in HS, indicating a more stable microbial community. Notably, network analysis at the species level revealed that S. aureus engaged in competitive interactions in NL and LE but not in HS. Whole-genome sequencing (WGS) showed considerable genetic diversity among S. aureus strains from AD. Despite this variability, the isolates exhibited convergence in key phenotypic traits such as adhesion and biofilm formation, which are crucial for microbial persistence. These common phenotypes suggest an adaptive evolution, driven by competition in the AD skin microenvironment, of S. aureus and underscoring the interplay between genetic diversity and phenotypic convergence in microbial adaptation.},
}

@article {pmid39381466,
year = {2024},
author = {Kaintura, A and Ramar, K},
title = {Comparative Evaluation of Biofilm Formation on Temporization Crown Materials Used in the Rehabilitation of Primary Dentition With Different Polishing Materials: An In Vitro Study.},
journal = {Cureus},
volume = {16},
number = {9},
pages = {e68944},
pmid = {39381466},
issn = {2168-8184},
abstract = {Introduction Advancements in dental materials have enhanced aesthetic treatments for managing dental caries and injuries in primary dentition. Bis-acryl composite-based temporization materials are now preferred for restoring primary crowns due to their superior properties. However, prolonged exposure to dietary and hygienic factors can lead to discoloration and roughness, making efficient polishing essential to prevent plaque buildup. Objective This study aims to evaluate Streptococcus mutans biofilm formation on temporization material polished with different polishing systems. Methods This study tested bis-acryl methacrylate temporization material. Thirty disk-shaped specimens were prepared and divided into three groups according to the polishing system used (n = 10 per group): Shofu Super Snap mini kit (Shofu, San Marcos, CA), aluminum oxide polishing paste, and propol polishing paste. Each group's specimens were polished according to the manufacturer's instructions. Surface roughness (SR), scanning electron microscopy (SEM) morphological analysis, and Streptococcus mutans biofilm formation were assessed for each group. Results The results showed significant differences in roughness average (Ra) values among the polishing materials, with the Shofu Super Snap mini kit having the highest roughness (Ra = 2.04), followed by propol polishing paste (Ra = 1.30) and aluminum oxide paste (Ra = 0.75). Additionally, polishing methods significantly affected mean colony-forming unit (CFU) levels, with the first group having the highest mean CFU value (0.24), with SEM images showing substantial biofilm formation by Streptococcus mutans. Conclusion Bacterial biofilm formation on the aluminum oxide paste group's surface differed from that on the propol polishing paste and aluminum oxide disc groups. The polishing techniques that we tested significantly influenced surface properties and biofilm formation. These findings suggest that selecting an appropriate polishing system can reduce the risk of gingival inflammation associated with temporization materials.},
}

@article {pmid39381027,
year = {2024},
author = {Szymczak, M and Golec, P},
title = {Long-Term Effectiveness of Engineered T7 Phages Armed with Silver Nanoparticles Against Escherichia coli Biofilm.},
journal = {International journal of nanomedicine},
volume = {19},
number = {},
pages = {10097-10105},
pmid = {39381027},
issn = {1178-2013},
mesh = {*Biofilms/drug effects ; *Metal Nanoparticles/chemistry ; *Silver/chemistry/pharmacology ; *Escherichia coli/drug effects ; *Bacteriophage T7/physiology ; Anti-Bacterial Agents/pharmacology/chemistry ; Phage Therapy ; Escherichia coli Infections ; Microbial Sensitivity Tests ; },
abstract = {The escalating threat of antibiotic-resistant bacteria, particularly those forming biofilm structures, underscores the urgent need for alternative treatment strategies. Bacteriophages have emerged as promising agents for combating bacterial infections, especially those associated with biofilm formation. However, the efficacy of phage therapy can be limited by the development of bacterial resistance and biofilm regrowth. Interestingly, phages could be combined with other agents, such as metal nanoparticles, to enhance their antibacterial effectiveness. Since the therapeutic strategy of using phages and metal nanoparticles has been developed relatively recently, evaluating its efficacy under various conditions is essential, with a particular focus on the duration of activity. This study tested the hypothesis that a novel approach to combating bacterial biofilms, based on phages armed with silver nanoparticles (AgNPs), would exhibit enhanced activity over an extended period after application. In this work, we investigated the potential of engineered T7 phages armed with AgNPs for eradicating Escherichia coli biofilm. We demonstrated that such biomaterial exhibits sustained antimicrobial activity even after prolonged exposure. Compared to phages alone or AgNPs alone, the biomaterial significantly enhances biofilm eradication, particularly after 48 hours of treatment. These findings highlight the potential of synergistic phage-nanoparticle strategies for combatting biofilm-associated infections.},
}

*Biofilms/drug effects
*Metal Nanoparticles/chemistry
*Silver/chemistry/pharmacology
*Escherichia coli/drug effects
*Bacteriophage T7/physiology
Anti-Bacterial Agents/pharmacology/chemistry
Phage Therapy
Escherichia coli Infections
Microbial Sensitivity Tests

@article {pmid39377591,
year = {2024},
author = {Shi, W and Li, Y and Zhang, W},
title = {Screening and functional characterization of isocitrate lyase AceA in the biofilm formation of Vibrio alginolyticus.},
journal = {Applied and environmental microbiology},
volume = {},
number = {},
pages = {e0069724},
doi = {10.1128/aem.00697-24},
pmid = {39377591},
issn = {1098-5336},
abstract = {Biofilm is a well-known sessile lifestyle for bacterial pathogens, but a little is known about the mechanism on biofilm formation in Vibrio alginolyticus. In this study, we screened V. alginolyticus strains with strong biofilm formation ability from coastal seawater. The antibiotic resistance of the biofilm cells (BFs) was higher than that of the planktonic cells (PTs). To study the genes and pathways involved in biofilm formation, we performed transcriptome analysis of the BFs and PTs of V. alginolyticus R9. A total of 685 differentially expressed genes (DEGs) were upregulated, and 517 DEGs were downregulated in the BFs. The upregulated DEGs were significantly enriched in several pathways including glyoxylate and dicarboxylate metabolism, while the downregulated genes were significantly enriched in the flagellar assembly pathways. The key gene involved in glyoxylate shunt, aceA, was cloned, and ΔaceA mutant was constructed to determine the function of AceA in carbon source utilization, biofilm formation, and virulence. Real-time reverse transcription PCR showed that the expression of aceA was higher at the mature stage but lower at the disperse stage of biofilm formation, and the expression of the flagellar related genes was upregulated in ΔaceA. This is the first study to illustrate the global gene expression profile during the biofilm formation of V. alginolyticus, and isocitrate lyase AceA, the key enzyme involved in glyoxylate shunt, was shown to maintain biofilms accompanied by downregulation of flagellation but promoted dispersal of BFs at the late stage.IMPORTANCEBiofilms pose serious public problems, not only protecting the cells in it from environmental hazard but also affecting the composition and abundance of bacteria, algae, fungi, and protozoa. The important opportunistic pathogen Vibrio alginolyticus is extremely ubiquitously present in seawater, and it also exhibited a strong ability to form biofilm; thus, investigation on the biofilm formation of V. alginolyticus at molecular level is fundamental for the deeper exploration of the environmental concerns arose by biofilm. In this study, transcriptome analysis of biofilm cells (BFs) and planktonic cells (PTs) from V. alginolyticus was performed and AceA was screened to play an important role in biofilm formation. AceA was shown to maintain biofilms accompanied by downregulation of flagellation but promoted dispersal of BFs at the disperse stage. This method was helpful to further understand the ability and mechanism of V. alginolyticus biofilm formation and provide clues for prevention of V. alginolyticus infection.},
}

@article {pmid39377107,
year = {2024},
author = {Sampaio, C and Cusicanqui Méndez, DA and Buzalaf, MAR and Pessan, JP and Cruvinel, T},
title = {Influence of different growth conditions on the composition and acidogenicity of saliva-derived microcosm biofilm and their effects on enamel demineralization.},
journal = {Biofouling},
volume = {},
number = {},
pages = {1-11},
doi = {10.1080/08927014.2024.2410781},
pmid = {39377107},
issn = {1029-2454},
abstract = {This study compared the influence of growth conditions on the composition and acidogenicity of saliva-derived microcosm biofilms and enamel demineralization. Biofilms grown in sucrose-supplemented modified McBain medium, containing 25/50 mmol/L PIPES (buffer), under anaerobiosis/microaerophilia, for 3 and 7 days were evaluated for their acidogenicity, microbial composition, matrix, and enamel mineral content. The viability of total lactobacilli was higher in the group containing 25 mmol/L PIPES grown under anaerobiosis, which also showed lower pH values. The viability of total streptococci and total microorganisms was significantly higher at 7 days in the groups with 50 mmol/L PIPES than at 3 days, regardless of the incubation atmosphere. No significant differences were observed in lactic acid, calcium, superficial hardness loss, or lesion depth. In conclusion, the incubation atmosphere, buffer content in the growth media, and duration of biofilm formation displayed species-varied influence on microcosm biofilms, without causing significant changes in acid metabolism or enamel demineralization.},
}

@article {pmid39376521,
year = {2024},
author = {Pakeeraiah, K and Swain, PP and Sahoo, A and Panda, PK and Mahapatra, M and Mal, S and Sahoo, RK and Sahu, PK and Paidesetty, SK},
title = {Multimodal antibacterial potency of newly designed and synthesized Schiff's/Mannich based coumarin derivatives: potential inhibitors of bacterial DNA gyrase and biofilm production.},
journal = {RSC advances},
volume = {14},
number = {43},
pages = {31633-31647},
pmid = {39376521},
issn = {2046-2069},
abstract = {The briskened urge to develop potential antibacterial candidates against multidrug-resistant pathogens has motivated the present research study. Herein, newly synthesized coumarin derivatives with azomethine and amino-methylated as the functional groups have been focused on their antibacterial efficacy. The study proposed two distinct series: 3-acetyl substituted coumarin derivatives, followed by the Schiff base approach (5a-5i), and formaldehyde-secondary cyclic amine-based derivatives (7a-7g), using the Mannich base approach, further the compounds have been confirmed through various spectral studies. Further, target-specific binding affinity has been affirmed via in silico study. In vitro antibacterial study suggested compounds 5d and 5f to be most effective against S. aureus and multidrug-resistant K. pneumoniae, with MIC values of 8 and 16 μg mL[-1]. Among them, the compounds 5d and 5f showed excellent binding scores against different bacterial gyrase compared to the standard novobiocin. Based on RMRS, RMSF, Rg, and H-bond plots, MD simulation study at 100 ns also suggested better stability of 5d inside gyraseB of E. coli than the complex of E. coli-GyrB-novobiocin. The toxicity and pharmacokinetic profiles showed favorable drug-likeness. Overall, systematic in vitro and in silico assessment suggested that multimodal antibacterial derivatives 5d and 5f strongly inhibit both bacterial DNA gyrase and biofilm formation of drug-resistant pathogens, suggesting their potency in mainstream antibacterial therapy.},
}

@article {pmid39376426,
year = {2024},
author = {Mujahid, ZA and Palal, SS and Gopan, G and Ramabhadraiah, AK},
title = {Biofilm Producing Organisms and Their Antibiotic Sensitivity in Chronic Suppurative Otitis Media: A Cross-Sectional Study.},
journal = {Indian journal of otolaryngology and head and neck surgery : official publication of the Association of Otolaryngologists of India},
volume = {76},
number = {5},
pages = {3886-3894},
pmid = {39376426},
issn = {2231-3796},
abstract = {Chronic Suppurative Otitis Media (CSOM) is an inflammation of the mucoperiosteal lining of the middle ear cleft. Recently, biofilms have been discovered to play a pivotal role in the pathogenesis of CSOM. A biofilm is a bacterial aggregation that adheres to the mucosal surfaces and is connected with an extracellular matrix. Biofilms enhance antibiotic resistance, facilitate genetic alterations and amplify competence to combat host immunity. This study aims to identify the spectrum of biofilm-producers in CSOM and investigate their antibiotic sensitivity. Samples (648) were obtained from the deeper part of external auditory meatus of patients with CSOM. Pus samples were collected and processed for culture sensitivity. Biofilms detected. The findings were compiled and statistically analyzed. Out of 500 culture-positive samples, most commonly isolated bacteria was Pseudomonas (62.6%), followed by MRSA (13.8%). Biofilm-producers were 350, with 119 being strong, 167 moderate, and 64 weak. Biofilms were produced by 70% of the isolates, with Pseudomonas producing the most (74.6%), followed by MRSA. Gentamicin was the most effective antibiotic against biofilm-producers. Amoxicillin-Clavulanic Acid, Ceftriaxone, Cefuroxime, and Minocyclin were resistant. Pseudomonas had the highest sensitivity to Levofloxacin (96.6%), followed by Ceftazidime and Ciprofloxacin. Pseudomonas was resistant to Cefuroxime, Amoxicillin-Clavulanic acid and Linezolid. Multi-drug resistance has been widespread among CSOM causal species, particularly in biofilm producers. Thus, screening for biofilm formation, in addition to the standard antibiogram, must be undertaken as part of CSOM protocol. This will address the multi-drug resistance and select an appropriate treatment modality.},
}

@article {pmid39375363,
year = {2024},
author = {Lander, SM and Fisher, G and Everett, BA and Tran, P and Prindle, A},
title = {Secreted nucleases reclaim extracellular DNA during biofilm development.},
journal = {NPJ biofilms and microbiomes},
volume = {10},
number = {1},
pages = {103},
pmid = {39375363},
issn = {2055-5008},
support = {1R35GM147170-01//U.S. Department of Health & Human Services | National Institutes of Health (NIH)/ ; NSF 2239567//National Science Foundation (NSF)/ ; W911NF-21-1-0291//United States Department of Defense | United States Army | U.S. Army Research, Development and Engineering Command | Army Research Office (ARO)/ ; F31GM143907//U.S. Department of Health & Human Services | NIH | National Institute of General Medical Sciences (NIGMS)/ ; },
mesh = {*Biofilms/growth & development ; *Bacillus subtilis/genetics ; *DNA, Bacterial/genetics ; Bacterial Proteins/genetics/metabolism ; Deoxyribonucleases/metabolism/genetics ; },
abstract = {DNA is the genetic code found inside all living cells and its molecular stability can also be utilized outside the cell. While extracellular DNA (eDNA) has been identified as a structural polymer in bacterial biofilms, whether it persists stably throughout development remains unclear. Here, we report that eDNA is temporarily invested in the biofilm matrix before being reclaimed later in development. Specifically, by imaging eDNA dynamics within undomesticated Bacillus subtilis biofilms, we found eDNA is produced during biofilm establishment before being globally degraded in a spatiotemporally coordinated pulse. We identified YhcR, a secreted Ca[2+]-dependent nuclease, as responsible for eDNA degradation in pellicle biofilms. YhcR cooperates with two other nucleases, NucA and NucB, to reclaim eDNA for its phosphate content in colony biofilms. Our results identify extracellular nucleases that are crucial for eDNA reclamation during biofilm development and we therefore propose a new role for eDNA as a dynamic metabolic reservoir.},
}

*Biofilms/growth & development
*Bacillus subtilis/genetics
*DNA, Bacterial/genetics
Bacterial Proteins/genetics/metabolism
Deoxyribonucleases/metabolism/genetics

@article {pmid39373511,
year = {2024},
author = {Richards, B and Robertson, S and Martinez Pomares, L and Cámara, M},
title = {Development of a Polymicrobial Colony Biofilm Model to Test Antimicrobials in Cystic Fibrosis.},
journal = {Journal of visualized experiments : JoVE},
volume = {},
number = {211},
pages = {},
doi = {10.3791/67213},
pmid = {39373511},
issn = {1940-087X},
mesh = {*Cystic Fibrosis/microbiology ; *Biofilms/drug effects/growth & development ; Humans ; Anti-Bacterial Agents/pharmacology ; Pseudomonas aeruginosa/drug effects/physiology ; Models, Biological ; Microbial Sensitivity Tests/methods ; },
abstract = {A range of bacteria biofilm models exist for the testing of antibiotics. However, many of these are limited to a single experimental output, such as colony-forming units or metabolic activity. Furthermore, many biofilm models do not reflect the biological and physiochemical properties of the human host environment. This is an important issue in many conditions, but most noticeably in cystic fibrosis (CF). A large proportion of people with CF suffer from both chronic and intermittent infections, and in vitro, antibiotic susceptibility testing poorly correlates with patient treatment outcomes. Some biofilm models incorporate CF lung-relevant media, including synthetic sputum mimics, but do not consider the polymicrobial nature of the environment, which alters biofilm architecture, physiology, and the way microbes respond to treatment. The solid-air interface colony biofilm model described here is highly adaptable and incorporates both CF-relevant media and a polymicrobial context. This model can also be used for mid-throughput screening of antimicrobials and to study their effect on polymicrobial dynamics. Output measurements from the model can be colony-forming units, metabolic activity, and confocal microscopy analysis. The model can easily be adapted to different microorganisms, media, temperatures, and variable oxygen conditions and can be used to test a wide range of chemical, biological, and physical treatments.},
}

*Cystic Fibrosis/microbiology
*Biofilms/drug effects/growth & development
Humans
Anti-Bacterial Agents/pharmacology
Pseudomonas aeruginosa/drug effects/physiology
Models, Biological
Microbial Sensitivity Tests/methods

@article {pmid39373165,
year = {2024},
author = {Zhang, TH and Yang, YK and Feng, YM and Luo, ZJ and Wang, MW and Qi, PY and Zeng, D and Liu, HW and Liao, YM and Meng, J and Zhou, X and Liu, LW and Yang, S},
title = {Engineering the novel azobenzene-based molecular photoswitches for suppressing bacterial infection through dynamic regulation of biofilm formation.},
journal = {Pest management science},
volume = {},
number = {},
pages = {},
doi = {10.1002/ps.8453},
pmid = {39373165},
issn = {1526-4998},
support = {//National Key Research and Development Program of China (2022YFD1700300)/ ; //National Natural Science Foundation of China (32372610, U23A20201, 32160661, 32202359/ ; //the Central Government Guides Local Science and Technology Development Fund Projects [Qiankehezhongyindi [2024]007]/ ; 32372610//National Natural Science Foundation of China/ ; U23A20201//National Natural Science Foundation of China/ ; 32160661//National Natural Science Foundation of China/ ; 32202359//National Natural Science Foundation of China/ ; 2022YFD1700300//National Key Research and Development Program of China/ ; [2024]007//Central Government Guides Local Science and Technology Development Fund Projects/ ; },
abstract = {BACKGROUND: Bacterial biofilm is a strong fortress for bacteria to resist harsh external environments, which can enhance their tolerance and exacerbate the drug/pesticide resistance risk. Currently, photopharmacology provides an advanced approach via precise spatiotemporal control for regulating biological activities by light-controlling the molecular configurations, thereby having enormous potential in the development of drug/pesticides.

RESULTS: To further expand the photopharmacology application for discovering new antibiofilm agents, we prepared a series of light-controlled azo-active molecules and explored their photo isomerization, fatigue resistance, and anti-biofilm performance. Furthermore, their mechanisms of inhibiting biofilm formation were systematically investigated. Overall, designed azo-derivative A11 featured excellent anti-Xoo activity with an half-maximal effective concentration (EC50) value of 5.45 μg mL[-1], and the EC50 value could be further elevated to 2.19 μg mL[-1] after ultraviolet irradiation (converted as cis-configuration). The photo-switching behavior showed that A11 had outstanding anti-fatigue properties. An in-depth analysis of the action mechanism showed that A11 could effectively inhibit biofilm formation and the expression of relevant virulence factors. This performance could be dynamically regulated via loading with private light-switch property.

CONCLUSION: In this work, designed light-controlled azo molecules provide a new model for resisting bacterial infection via dynamic regulation of bacterial biofilm formation. © 2024 Society of Chemical Industry.},
}

@article {pmid39372729,
year = {2024},
author = {Yang, Y and Yan, J and Olson, R and Jiang, X},
title = {Comprehensive Genomic and Evolutionary Analysis of Biofilm Matrix Clusters and Proteins in the Vibrio Genus.},
journal = {bioRxiv : the preprint server for biology},
volume = {},
number = {},
pages = {},
doi = {10.1101/2024.08.19.608685},
pmid = {39372729},
issn = {2692-8205},
abstract = {Vibrio cholerae pathogens cause cholera, an acute diarrheal disease resulting in significant morbidity and mortality worldwide. Biofilm formation by V. cholerae enhances its survival in natural ecosystems and facilitates transmission during cholera outbreaks. Critical components of the biofilm matrix are the Vibrio polysaccharide (VPS) produced by the vps-1 and vps-2 gene clusters, and biofilm matrix proteins encoded in the rbm cluster. However, the biofilm matrix clusters and associated matrix proteins in other Vibrio species remain under investigated, and their evolutionary patterns are largely unknown. In this study, we systematically annotated the biofilm matrix clusters across 6,121 Vibrio genomes, revealing their distribution, diversity, and evolution. We found that biofilm matrix clusters not only exist in V. cholerae but also in phylogenetically distant Vibrio species. Additionally, vps-1 clusters tend to co-locate with rbmABC genes, while vps-2 clusters are often adjacent to rbmDEF genes in various Vibrio species, which helps explain the separation of these clusters by the rbm cluster in well-characterized V. cholerae strains. Evolutionary analysis of RbmC and Bap1 reveals that these two major biofilm matrix proteins are sequentially and structurally related and have undergone domain/modular alterations during their evolution. RbmC genes are more prevalent, while bap1 likely resulted from an ancient duplication event of rbmC and is only present in a major clade of species containing rbmC counterparts. Notably, a novel loop-less Bap1 variant, identified in two subspecies clades of V. cholerae, was found to be associated with altered biofilm formation and the loss of antibiotic efflux pumps and chemotaxis. Another rbm cluster gene, rbmB, involved in biofilm dispersal, was found to share a common ancestor with Vibrio prophage pectin lyase-like tail proteins, indicating its functional and evolutionary linkages to Vibriophage proteins. In summary, our findings establish a foundational understanding of the proteins and gene clusters that contribute to Vibrio biofilm formation from an evolutionary perspective across a broad taxonomic scale. This knowledge paves the way for future strategies aimed at engineering and controlling biofilms through genetic modification.},
}

@article {pmid39370609,
year = {2024},
author = {Islam, MS and Alatishe, A and Lee-Lopez, CC and Serrano, F and Yukl, ET},
title = {H-NOX Influences Biofilm Formation, Central Metabolism, and Quorum Sensing in Paracoccus denitrificans.},
journal = {Journal of proteome research},
volume = {},
number = {},
pages = {},
doi = {10.1021/acs.jproteome.4c00466},
pmid = {39370609},
issn = {1535-3907},
abstract = {The transition from planktonic to biofilm growth in bacteria is often accompanied by greater resistance to antibiotics and other stressors, as well as distinct alterations in physical traits, genetic activity, and metabolic restructuring. In many species, the heme nitric oxide/oxygen binding proteins (H-NOX) play an important role in this process, although the signaling mechanisms and pathways in which they participate are quite diverse and largely unknown. In Paracoccus denitrificans, deletion of the hnox gene results in a severe biofilm-deficient phenotype. Quantitative proteomics was used to assemble a comprehensive data set of P. denitrificans proteins showing altered abundance of those involved in several important metabolic pathways. Further, decreased levels of pyruvate and elevated levels of C16 homoserine lactone were detected for the Δhnox strain, associating the biofilm deficiency with altered central carbon metabolism and quorum sensing, respectively. These results expand our knowledge of the important role of H-NOX signaling in biofilm formation.},
}

@article {pmid39369508,
year = {2024},
author = {Jang, Y and Lee, SH and Kim, NK and Park, HD},
title = {Metagenomic analysis reveals abundance of mixotrophic, heterotrophic, and homoacetogenic bacteria in a hydrogen-based membrane biofilm reactor.},
journal = {Water research},
volume = {267},
number = {},
pages = {122564},
doi = {10.1016/j.watres.2024.122564},
pmid = {39369508},
issn = {1879-2448},
abstract = {Heterotrophic microorganisms are frequently observed in hydrogenotrophic denitrification systems and are presumed to contribute to their improved performance. However, their roles and metabolic pathways in the hydrogen-based membrane biofilm reactor (H2-MBfR) system remain unclear. The objective of this study was to elucidate the underlying mechanisms driving heterotrophic denitrification. For this purpose, metagenomic analysis was conducted on an H2-MBfR showing higher denitrification performance, focusing on the metabolic function of the microbial community. Functional genes related to H2 oxidation, organic carbon metabolism, and denitrification were the major targets of interest. This analysis revealed a substantial number of genes associated with the oxidation of organic carbon compounds in the biofilm, suggesting its potential for heterotrophic denitrification. Investigation of the genes of interest in metagenome-assembled genomes (MAGs) has demonstrated a predominance of mixotrophs or heterotrophs rather than obligate autotrophs. Notably, MAGs exhibiting the highest abundance of genes of interest were affiliated with Hydrogenophaga and Thauera, implying their significant role in denitrifying the H2-MBfR as mixotrophs utilizing both H2 and organic substrates. The identification of 11 MAGs, presumed to originate from homoacetogens suggested that acetate might contribute to the proliferation of heterotrophs. Based on these metagenomic findings, possible metabolic pathways were identified to explain heterotrophic denitrification within the H2-MBfR biofilms.},
}

@article {pmid39369013,
year = {2024},
author = {Klein, EM and Heintz, H and Wurst, R and Schuldt, S and Hähl, H and Jacobs, K and Gescher, J},
title = {Comparative analysis of the influence of BpfA and BpfG on biofilm development and current density in Shewanella oneidensis under oxic, fumarate- and anode-respiring conditions.},
journal = {Scientific reports},
volume = {14},
number = {1},
pages = {23174},
pmid = {39369013},
issn = {2045-2322},
mesh = {*Shewanella/genetics/physiology/metabolism ; *Biofilms/growth & development ; *Fumarates/metabolism ; *Electrodes ; Bacterial Proteins/genetics/metabolism ; Bioelectric Energy Sources/microbiology ; Oxygen/metabolism ; },
abstract = {Biofilm formation by Shewanella oneidensis has been extensively studied under oxic conditions; however, relatively little is known about biofilm formation under anoxic conditions and how biofilm architecture and composition can positively influence current generation in bioelectrochemical systems. In this study, we utilized a recently developed microfluidic biofilm analysis setup with automated 3D imaging to investigate the effects of extracellular electron acceptors and synthetic modifications to the extracellular polymeric matrix on biofilm formation. Our results with the wild type strain demonstrate robust biofilm formation even under anoxic conditions when fumarate is used as the electron acceptor. However, this pattern shifts when a graphite electrode is employed as the electron acceptor, resulting in biofilm formation falling below the detection limit of the optical coherence tomography imaging system. To manipulate biofilm formation, we aimed to express BpfG with a single amino acid substitution in the catalytic center (C116S) and to overexpress bpfA. Our analyses indicate that, under oxic conditions, overarching mechanisms predominantly influence biofilm development, rather than the specific mutations we investigated. Under anoxic conditions, the bpfG mutation led to a quantitative increase in biofilm formation, but both strains exhibited significant qualitative changes in biofilm architecture compared to the controls. When an anode was used as the sole electron acceptor, both the bpfA and bpfG mutations positively impacted mean current density, yielding a 1.8-fold increase for each mutation.},
}

*Shewanella/genetics/physiology/metabolism
*Biofilms/growth & development
*Fumarates/metabolism
*Electrodes
Bacterial Proteins/genetics/metabolism
Bioelectric Energy Sources/microbiology
Oxygen/metabolism

@article {pmid39368992,
year = {2024},
author = {Margot, C and Rhoads, W and Gabrielli, M and Olive, M and Hammes, F},
title = {Dynamics of drinking water biofilm formation associated with Legionella spp. colonization.},
journal = {NPJ biofilms and microbiomes},
volume = {10},
number = {1},
pages = {101},
pmid = {39368992},
issn = {2055-5008},
support = {Aramis nr.:4.20.01//Bundesamt für Lebensmittelsicherheit und Veterinärwesen (Federal Food Safety and Veterinary Office)/ ; },
mesh = {*Biofilms/growth & development ; *Legionella/physiology/classification/growth & development/genetics ; *Drinking Water/microbiology ; *RNA, Ribosomal, 18S/genetics ; Water Microbiology ; Sequence Analysis, DNA ; },
abstract = {Understanding how Legionella spp. proliferate in multispecies biofilms is essential to develop strategies to control their presence in building plumbing. Here, we analyzed biofilm formation and Legionella spp. colonization on new plumbing material during 8 weeks. Biofilm formation was characterized by an initial increase in intact cell concentrations up to 9.5 × 10[5] cells/cm[2], followed by a steady decrease. We identified Comamonas, Caulobacter, Schlegella, Blastomonas and Methyloversatilis as pioneer genera in the biofilm formation process. Importantly, L. pneumophila was the dominant Legionella spp. and rapidly colonized the biofilms, with culturable cell concentrations peaking at 3.1 × 10[4] MPN/cm[2] after 4 weeks already. Moreover, several Legionella species co-occurred and had distinct dynamics of biofilm colonization. Vermamoeba vermiformis (V. vermiformis) was the dominant protist identified with 18S rRNA gene amplicon sequencing. Together our results highlight that biofilm formation upon introduction of new building plumbing material is a dynamic process where pathogenic Legionella species can be part of the earliest colonizers.},
}

*Biofilms/growth & development
*Legionella/physiology/classification/growth & development/genetics
*Drinking Water/microbiology
*RNA, Ribosomal, 18S/genetics
Water Microbiology
Sequence Analysis, DNA

@article {pmid39368846,
year = {2024},
author = {Hartono Adji, RP and Anshori, I and Manurung, RV and Taufiqqurrachman, and Mahmudin, D and Daud, P and Kurniadi, DP and Pristianto, EJ and Rahman, AN and Desvasari, W and Sulistyaningsih, and Mandasari, RD and Hiskia, and Wiranto, G},
title = {Retraction notice to "A comprehensive study on transparent conducting oxides in compact microbial fuel cells: Integrated spectroscopic and electrochemical analyses for monitoring biofilm growth" [Biosens. Bioelectron. 250 (2024) 116067].},
journal = {Biosensors & bioelectronics},
volume = {},
number = {},
pages = {116812},
doi = {10.1016/j.bios.2024.116812},
pmid = {39368846},
issn = {1873-4235},
}

@article {pmid39368628,
year = {2024},
author = {Mei, N and Jia, F and Wang, H and Hu, Z and Han, B and Chen, Y and Zhao, X and Han, X and Zhang, J and Li, D and Yao, H and Guo, J},
title = {Partitioned granular sludge coupling with membrane-aerated biofilm reactor for efficient autotrophic nitrogen removal.},
journal = {Bioresource technology},
volume = {},
number = {},
pages = {131570},
doi = {10.1016/j.biortech.2024.131570},
pmid = {39368628},
issn = {1873-2976},
abstract = {The partial nitritation-anammox process based on a membrane-aerated biofilm reactor (MABR) faces several challenges, such as difficulty in suppressing nitrite-oxidizing bacteria (NOB), excessive effluent nitrate, and ineffective synergy between denitrification and anammox bacteria. Therefore, a novel partitioned granular sludge coupling with MABR (G-MABR) was constructed. The chemical oxygen demand (COD) and nitrogen removal efficiency were 88.8 ± 1.8 %-92.6 ± 1.2 % and 88.8 ± 1.5 %-93.6 ± 0.7 %, respectively. The COD was mainly lowered in the lower granular sludge-zone, while nitrogen was removed in the upper MABR-zone. NOB was significantly suppressed in the MABR-zone due to competition for substrate with denitrifying bacteria and anammox bacteria. This partitioned configuration reduced the C/N ratio in the MABR-zone, thus facilitating autotrophic nitrogen removal. Both partial nitrification and denitrification provided nitrite for anammox bacteria in granular sludge, whereas partial nitrification mainly supplied nitrite to the anammox bacteria in membrane biofilms.},
}

@article {pmid39368567,
year = {2024},
author = {Ofori, P and Zemliana, N and Zaffran, I and Etzion, T and Sionov, RV and Steinberg, D and Mechoulam, R and Kogan, NM and Levi-Schaffer, F},
title = {Antifungal properties of Abnormal Cannabinoid derivatives: Disruption of Biofilm Formation and Gene Expression in Candida Species.},
journal = {Pharmacological research},
volume = {},
number = {},
pages = {107441},
doi = {10.1016/j.phrs.2024.107441},
pmid = {39368567},
issn = {1096-1186},
abstract = {Abnormal cannabinoids (including comp 3) are a class of synthetic lipid compounds with non-psychoactive properties and regioisomer configurations, but distinct from traditional cannabinoids since they do not interact with the established CB1 and CB2 receptors. Previous research showed the cardioprotective and anti-inflammatory potentials of comp 3 and more recently its antimicrobial effect on methicillin-resistant Staphylococcus aureus (MRSA). Given the escalating challenges posed by Candida infections and the rise of antifungal drug resistance, the exploration of novel therapeutic avenues is crucial. This study aimed to assess the anti-Candida properties of newly synthesized AbnCBD derivatives. AbnCBD derivatives were synthesized by acid catalysis-induced coupling and further derivatized. We evaluated the potential of the AbnCBD derivatives to inhibit the growth stages of various Candida species. By in vitro colorimetric assays and in vivo mice experiments, we have shown that AbnCBD derivatives induce differential inhibition of Candida growth. The AbnCBD derivatives, especially comp 3, comp 10, and comp 9 significantly reduced the growth of C. albicans, including FLC-resistant strains, and of C. tropicalis and C. parapsilosis but not of C auris compared to their controls (FLC and 0.5% DMSO). Comp 3 also disrupted C. albicans biofilm formation and eradicated mature biofilms. Notably, other derivatives of AbnCBD disrupted the biofilm formation and maturation of C. albicans but did not affect yeast growth. In a murine model of VVC, comp 3 demonstrated significant fungal clearance and reduced C. albicans burden compared to vehicle and FLC controls. These findings highlight the potential of AbnCBDs as promising antifungal agents against Candida infections.},
}

@article {pmid39368563,
year = {2024},
author = {Manna, T and Chandra Guchhait, K and Jana, D and Dey, S and Karmakar, M and Hazra, S and Manna, M and Jana, P and Panda, AK and Ghosh, C},
title = {Wastewater-based surveillance of Vibrio cholerae: Molecular insights on biofilm regulatory diguanylate cyclases, virulence factors and antibiotic resistance patterns.},
journal = {Microbial pathogenesis},
volume = {196},
number = {},
pages = {106995},
doi = {10.1016/j.micpath.2024.106995},
pmid = {39368563},
issn = {1096-1208},
abstract = {Vibrio cholerae is an inherent inhabitant of aquatic ecosystems. The Indian state of West Bengal, especially the Gangetic delta region is the highest cholera affected region and is considered as the hub of Asiatic cholera. V. cholerae were isolated from publicly accessible wastewater of Midnapore, West Bengal, India. Serotyping determined all isolates to be of non-O1/non-O139 serogroups. Moderate biofilm-forming abilities were noticed in most of the isolates (74.7 %) while, high biofilm formation was recorded for only 6.3 % isolates and 19 % of isolates exhibited low/non-biofilm-forming abilities. PCR-based screening of crucial diguanylate cyclases (DGCs) involved in cyclic-di-GMP-mediated biofilm signaling was performed. cdgH and cdgM were the most abundant DGCs among 93.7 % and 91.5 % of isolates, respectively. Other important DGCs, i.e., cdgK, cdgA, cdgL, and vpvC were present in 84 %, 75.5 %, 72 % and 68 % of isolates, respectively. Besides, the non-O1/non-O139 isolates were screened for the occurrence of virulence factor encoding genes. Moreover, among these non-O1/non-O139 isolates, two strains (3.17 %) harbored both ctxA and ctxB genes, which encode the cholera toxin associated with epidemic cholera. ompU was the most prevalent virulence factor, present in 24.8 % of isolates. Other virulence factors like, zot and st were found in 4.7 % and 9.5 % of isolates. Genes encoding tcp and ace were found to be PCR-negative for the isolates. Additionally, crucial virulence factor regulators, toxT, toxR and hapR were found to be PCR-positive in all the isolates. Antibiotic resistance patterns displayed further vulnerabilities with decreased sensitivity towards commonly used antibiotics with multiple antibiotic resistance index ranging between 0.37 and 0.62. The presence of cholera toxin-encoding multi-drug resistant (MDR) V. cholerae strains in environmental settings is alarming. High occurrence of DGCs are considered to encourage further investigations to use them as alternative therapeutic targets against MDR cholera pathogen due to their unique presence in bacterial systems.},
}

@article {pmid39367886,
year = {2024},
author = {Zhang, J and Hao, J and Wang, J and Li, H and Zhao, D},
title = {Strategic manipulation of biofilm dispersion for controlling Listeria monocytogenes infections.},
journal = {Critical reviews in food science and nutrition},
volume = {},
number = {},
pages = {1-10},
doi = {10.1080/10408398.2024.2409340},
pmid = {39367886},
issn = {1549-7852},
abstract = {Listeria monocytogenes (L. monocytogenes), a gram-positive foodborne pathogen that can easily cause listeriosis. It secretes extracellular polymers and forms biofilms that are highly resistant to disinfection methods, such as UV light and germicides, posing risks to food processing equipment and food quality. Dispersion of biofilm is the cycle of its formation in which the bacteria return to planktonic state and become susceptible to antimicrobials, the strategic manipulation of biofilm dispersion is thus heralded as a novel and promising approach for the effective control of biofilm-related infections. Compared to the traditional methods, it is more effective to start with the composition of biofilms, cut off the production of their constituent substances, and genetically reduce the probability of biofilm formation. Meanwhile, the dispersion of bacteria can be supplemented with exogenous substances, making long-term control possible. This paper provides a brief but comprehensive overview of the mechanisms of L. monocytogenes biofilms or cross-contamination and their resistance properties, and facilitates our understanding and control of the prevention and containment of L. monocytogenes biofilm contamination based on the biofilm's active and passive diffusion strategies. This work provides practical guidelines for the food industry to guard against the enduring threat to food safety due to L. monocytogenes biofilms.},
}

@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.},
}