Biofilm最新文献

{"title":"A comprehensive analysis of the effect of quorum-sensing molecule 3-oxo-C12-homoserine lactone on Candida auris and Candida albicans","authors":"Fruzsina Kovács ,&nbsp;Ágnes Jakab ,&nbsp;Noémi Balla ,&nbsp;Zoltán Tóth ,&nbsp;Dávid Balázsi ,&nbsp;Lajos Forgács ,&nbsp;Andrea Harmath ,&nbsp;Aliz Bozó ,&nbsp;Ágota Ragyák ,&nbsp;László Majoros ,&nbsp;Renátó Kovács","doi":"10.1016/j.bioflm.2025.100259","DOIUrl":"10.1016/j.bioflm.2025.100259","url":null,"abstract":"<div><div><em>Candida auris</em> occupies similar niches in various infections as <em>Pseudomonas aeruginosa</em>; however, the details of their interspecies communication remain largely unknown. To gain deeper insights into this relationship, phenotypic and transcriptomic analyses were conducted in the presence of the primary <em>P. aeruginosa</em> quorum-sensing molecule, N-(3-oxododecanoyl)-<span>l</span>-homoserine lactone (HSL), against <em>C. auris</em>, with the results compared to those of <em>C. albicans</em>. Our findings indicate that HSL-induced effects are not specific to <em>C. albicans</em>; additionally, several characteristics are present in <em>C. auris</em> but not in <em>C. albicans</em> following HSL exposure. Significant HSL-induced reduction was observed in growth and adhesion of <em>C. auris</em> cells in time -and concentration-dependent way (<em>p</em> &lt; 0.01-0.001). Moreover, HSL reduced intracellular iron and zinc levels (<em>p</em> &lt; 0.05-0.001); furthermore, it modulated <em>C. auris</em> metabolism toward beta-oxidation, which may be associated with the observed reduction in <em>in vivo</em> virulence at lower HSL concentrations compared with <em>C. albicans</em>. RNA-sequencing transcriptome analysis of <em>C. auris</em> revealed 67 and 306 upregulated genes, as well as 111 and 168 downregulated genes, in response to 100 and 200-μM HSL, respectively. We identified 45 overlapping upregulated and 25 overlapping downregulated genes between the two HSL concentrations. Similar to other <em>Candida</em>-derived C12 compounds (e.g., farnesol), HSL reduces several <em>C. auris</em> survival strategies, which may significantly influence the nature of <em>P. aeruginosa–C. auris</em> co-habitation. In conclusion, the obtained findings on <em>C. auris</em> do not provide clear evidence that HSL mediated effects have any favourable consequences in terms of <em>P. aeruginosa</em>-<em>C. auris</em> co-colonisation and/or co-infections.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"9 ","pages":"Article 100259"},"PeriodicalIF":5.9,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143101123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Co-culture biofilm patterns among different Pseudomonas aeruginosa clones from cystic fibrosis patients","authors":"Irene Cadenas-Jiménez ,&nbsp;Morten Levin Rybtke ,&nbsp;Doaa Higazy ,&nbsp;Sara Martí-Martí ,&nbsp;Tim Tolker-Nielsen ,&nbsp;Oana Ciofu ,&nbsp;Niels Høiby","doi":"10.1016/j.bioflm.2025.100257","DOIUrl":"10.1016/j.bioflm.2025.100257","url":null,"abstract":"<div><h3>Background</h3><div><em>Pseudomonas aeruginosa</em> chronic lung infection is the leading cause of death in the cystic fibrosis (CF) population. The high genome versatility of this microorganism allows it to adapt to the hostile CF lung where the same clone can persist for decades. Paranasal sinuses serve as a reservoir for bacterial adaptation before lung infection. Our study investigates biofilm compatibility among identical and different <em>P. aeruginosa</em> genotypes from sinus and lungs of CF patients. Strains were further characterized by whole genome sequencing and motility assays were performed.</div></div><div><h3>Methodology</h3><div>Motility, gentamicin susceptibility and growth rates were assessed in four strains coming from three CF patients. The strains were subjected to whole genome sequencing with the Illumina MiSeq platform.</div><div>Conjugation assays using the mini Tn7 transposon were performed in order to tag bacteria with the fluorescent proteins YFP (yellow) and CFP (cyan). Biofilm experiments were carried out in a flow cell system and images were acquired using a confocal laser microscope (CLSM) on days 3 and 5. Four experiments were performed: Experiment 1 with two clonal isolates from sinus and lungs from patient P01 (CF430-142, CF430-11621); experiments 2 (CF430-11621 + 75885-B) and 3 (CF430-11621 + 80271-B) with two lung isolates belonging to two different clones from different patients (P02, P03) and experiment 4 with one lung strain (CF430-11621) and <em>P. aeruginosa</em> PAO1 reference strain.</div></div><div><h3>Results</h3><div><em>P. aeruginosa</em> clonal isolates coming from paranasal sinuses and lungs from the same patient were able to form mixed biofilm. When different clones were employed no mixed biofilms were observed. Similar results were observed when combining the lung strain and the reference strain PAO1. Biofilms of both strains were observed in the flow-cell channels but no mixed biofilms of them were observed, with the exception of strain 75887-B which did not appear to form any biofilm when mixed with strain CF430-11621. All strains performed swarming while strains CF430-142 and 75887B lacked twitching motility. An aminoacidic change in SadB was observed in the strain 75887B.</div></div><div><h3>Conclusion</h3><div>Mixed biofilms were only observed when identical clones from the same patient were cultured together. Our experiments indicate that twitching motility does not significantly affect biofilm formation or architecture in our isolates.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"9 ","pages":"Article 100257"},"PeriodicalIF":5.9,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143101122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Legionella pneumophila response to shifts in biofilm structure mediated by hydrodynamics","authors":"Ana Rosa Silva ,&nbsp;C. William Keevil ,&nbsp;Ana Pereira","doi":"10.1016/j.bioflm.2025.100258","DOIUrl":"10.1016/j.bioflm.2025.100258","url":null,"abstract":"<div><div>Preventing legionellosis in water systems demands effective hydrodynamic management and biofilm mitigation. This study investigates the complex relationship between hydrodynamics (80 RPM and stagnation), biofilm mesoscale structure and <em>Legionella pneumophila</em> colonization, by addressing three key questions: (1) How do low flow <em>vs</em> stagnation conditions affect biofilm response to <em>L. pneumophila</em> colonization?, (2) How do biofilm structural variations mediate <em>L. pneumophila</em> migration across the biofilm?, and (3) Can specific hydrodynamic conditions trigger <em>L. pneumophila</em> entrance in a viable but nonculturable (VBNC) state? It was found that <em>Pseudomonas fluorescens</em> biofilms exhibit different responses to <em>L. pneumophila</em> based on the prevailing hydrodynamic conditions. While biofilm thickness and porosity decreased under shear (80 RPM), thickness tends to significantly increase when pre-established 80 RPM-grown biofilms are set to stagnation upon <em>L. pneumophila</em> spiking. Imposing stagnation after the spiking also seemed to accelerate <em>Legionella</em> migration towards the bottom of the biofilm. Water structures in the biofilm seem to be key to <em>Legionella</em> migration across the biofilm. Finally, shear conditions favoured the transition of <em>L. pneumophila</em> to VBNC states (∼94 %), despite the high viable cell counts (∼8 log₁₀ CFU/cm²) found throughout the experiments. This research highlights the increased risk posed by biofilms and stagnation, emphasizing the importance of understanding the mechanisms that govern <em>Legionella</em> behaviour in diverse biofilm environments. These insights are crucial for developing more effective monitoring and prevention strategies in water systems.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"9 ","pages":"Article 100258"},"PeriodicalIF":5.9,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143100621","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integration of BrfS into the biofilm-controlling cascade promotes sessile Salmonella growth at low temperatures","authors":"Gonzalo Tulin ,&nbsp;Andrea A.E. Méndez ,&nbsp;Nicolás R. Figueroa ,&nbsp;Carol Smith ,&nbsp;María P. Folmer ,&nbsp;Diego Serra ,&nbsp;Joseph T. Wade ,&nbsp;Susana K. Checa ,&nbsp;Fernando C. Soncini","doi":"10.1016/j.bioflm.2025.100254","DOIUrl":"10.1016/j.bioflm.2025.100254","url":null,"abstract":"<div><div>Biofilm formation is stimulated by different stress-related physiological and environmental conditions. In <em>Salmonella</em> and <em>Escherichia coli</em>, curli fibers and phosphoethanolamine-cellulose are the major extracellular components of biofilms. The production of both is under the control of CsgD, a transcriptional regulator whose expression is modulated by a number of factors responding to different signals. The atypical MerR-like regulator MlrA is key in the activation of <em>csgD</em> transcription in both <em>Salmonella</em> and <em>E. coli</em>. Recently, MlrB, a SPI-2-encoded MlrA-like regulator that counteracts MlrA by repressing <em>csgD</em> transcription and biofilm formation inside macrophages was identified. Here, we characterize STM1266, a <em>Salmonella</em>-specific MlrA-like regulator, recently renamed BrfS. In contrast to <em>mlrA</em>, <em>brfS</em> transcription increases in minimal growth media and at 20 °C, a temperature not commonly tested in laboratories. Under these conditions, as well as in salt-limited rich medium, deletion or overexpression of <em>brfS</em> affects extracellular matrix production. Using transcriptomics, we uncovered genes under BrfS control relevant for biofilm formation such as <em>csgB</em> and <em>bapA</em>. Transcriptional analysis of these genes in mutants lacking <em>brfS</em>, <em>csgD</em> or both, indicates that BrfS controls curli biosynthesis both in a CsgD-dependent and independent manner. By contrast, at low temperatures, <em>bapA</em> transcription depends only on BrfS, and neither deletion of <em>csgD</em> nor of <em>mlrA</em> modify its expression. Based on these results, we propose that BrfS contributes to <em>Salmonella</em> persistence in the environment, where the pathogen encounters low temperatures and nutrient limitation.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"9 ","pages":"Article 100254"},"PeriodicalIF":5.9,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143100620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Role of SMF-1 and cbl pili in Stenotrophomonas maltophilia biofilm formation","authors":"Radhika Bhaumik ,&nbsp;Alli Beard ,&nbsp;Oliver Harrigan ,&nbsp;Layla Ramos-Hegazy ,&nbsp;Seema Mattoo ,&nbsp;Gregory G. Anderson","doi":"10.1016/j.bioflm.2025.100253","DOIUrl":"10.1016/j.bioflm.2025.100253","url":null,"abstract":"<div><div><em>Stenotrophomonas maltophilia</em> is an emerging multidrug-resistant, Gram-negative opportunistic pathogen. It causes many healthcare-associated infections such as sepsis, endocarditis, meningitis, and catheter-related urinary tract infections. It also affects individuals with cystic fibrosis, exacerbating their lung condition. <em>S. maltophilia</em> often causes pathogenesis through the formation of biofilms. However, the molecular mechanisms <em>S. maltophilia</em> uses to carry out these pathogenic steps are unclear. The SMF-1 chaperone/usher pilus has been thought to mediate <em>S. maltophilia</em> attachment. To confirm this role, we created an isogenic deletion of the <em>smf-1</em> pilin gene and observed a defect in biofilm compared to wild type. We also discovered an additional chaperone/usher pilus gene cluster: <em>cbl</em>. Mutation of <em>cbl</em> also affects biofilm levels. Intriguingly, through transmission electron microscopy studies, we found suggestive evidence that the mutation of one pilus (<em>e.g. smf</em>) is not phenotypically compensated by another (<em>e.g. cbl</em>). Additionally, infection of <em>Galleria mellonella</em> larvae revealed increased virulence of an <em>smf-1</em> deletion mutant and an <em>smf-1 cbl</em> double deletion mutant. Together, these studies show that pili have an important role in switching between acute and chronic infections in conducting <em>S. maltophilia</em> virulence. Understanding their activity may help identify therapeutic targets for this pathogen.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"9 ","pages":"Article 100253"},"PeriodicalIF":5.9,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143101634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a tri-species wound model for studying fungal-bacterial interactions and antimicrobial therapies","authors":"Stine Sørensen ,&nbsp;Lasse Kvich ,&nbsp;Yijuan Xu ,&nbsp;Trine R. Thomsen ,&nbsp;Thomas Bjarnsholt ,&nbsp;Ida Thaarup","doi":"10.1016/j.bioflm.2025.100256","DOIUrl":"10.1016/j.bioflm.2025.100256","url":null,"abstract":"<div><div>Chronic wounds are increasing in numbers and biofilm-producing bacteria are highly prevalent in these wounds and often create resilient polymicrobial infections. Moreover, estimates suggest that up to 23 % of wounds contain fungi, particularly <em>Candida albicans</em>. Currently, inter-kingdom chronic wound models are scarce; thus, this study presents one of the few <em>in vitro</em> models that incorporate both bacterial and fungal species in a wound-relevant environment, addressing a critical gap in current biofilm research. The newly developed model contained the commonly isolated wound bacteria <em>Pseudomonas aeruginosa</em> and <em>Staphylococcus aureus</em>, and the fungus <em>Candida albicans</em>. Inter-species interactions were investigated through selective plate counting and pH and oxygen measurements, as well as confocal microscopy. Investigations were carried out before and after exposure to commonly used clinical antimicrobial treatments, including silver-infused bandages. When grown in a tri-species consortium, <em>P. aeruginosa</em> and <em>S. aureus</em> exhibited a higher tolerance towards silver-infused bandages than when they were grown individually. This suggests that <em>C. albicans</em> plays a protective role for the bacteria. In addition, the treatment also caused a shift in species ratios, moving from a <em>P. aeruginosa</em>-dominated consortium to a <em>S. aureus</em>-dominated consortium. Moreover, confocal microscopy revealed a change in biofilm architecture when comparing single-species models to tri-species models. Finally, we observed that silver-infused bandages increased the pH in the tri-species model as well as partially restoring the oxygenation within the wound model. In conclusion, our novel model exemplifies how inter-kingdom interactions in fungal-bacterial infections can complicate both the microenvironment and treatment efficacy.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"9 ","pages":"Article 100256"},"PeriodicalIF":5.9,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143100579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Examining the impact of probiotic Lactiplantibacillus pentosus 6MMI on inhibiting biofilm formation, adhesion, and virulence gene expression in Listeria monocytogenes ATCC 19115","authors":"Behrooz Alizadeh Behbahani ,&nbsp;Mostafa Rahmati-Joneidabad ,&nbsp;Morteza Taki","doi":"10.1016/j.bioflm.2025.100255","DOIUrl":"10.1016/j.bioflm.2025.100255","url":null,"abstract":"<div><div>Probiotic bacteria improve human health by secreting pro-microbial substances, balancing intestinal flora, binding to the mucous membrane and epithelium, strengthening the intestinal epithelial barrier, and creating interactions between the gastrointestinal microbiota and the immune system. This study aimed to investigate the probiotic potential, biofilm-related gene expression and anti-biofilm capabilities of <em>Lactiplantibacillus pentosus</em> 6MMI. The strain exhibited remarkable resilience to challenging conditions, including acidic environments, gastrointestinal settings, and bile salts. Notably, <em>Lpb. pentosus</em> demonstrated significant hydrophobicity (71.89 %), auto-aggregation (42.39 %), co-aggregation (51.28 %), antioxidant activity (ranging from 42.29 % to 64.61 %), and a cholesterol reduction capacity of 50.31 %. Its competitive abilities against <em>Listeria monocytogenes</em> were quantified, showing a competition rate of 54.51 %, displacement rate of 48.57 %, and inhibition of adhesion at 27.71 %. Also, <em>Lpb. pentosus</em> resulted an adhesion rate of 12.91 % to epithelial cells and showed no DNase or hemolytic activity. The strain exhibited the highest resistance to nalidixic acid, with an inhibition zone measuring 15.20 mm, while it was least resistant to chloramphenicol, which had an inhibition zone of 27.30 mm. Treatment with cell-free supernatant (CFS) from <em>Lpb. pentosus</em> significantly reduced biofilm formation by 91.25 % and 24.50 % and diminished mature biofilm formation by 83.82 % and 21.80 % on <em>L. monocytogenes</em>. Additionally, the CFS inhibited the transcription of the <em>plcB</em>, <em>hly</em>, and <em>prfA</em> genes in <em>L. monocytogenes</em>, suggesting a potential reduction in bacterial virulence through decreased hemolysin release and modulation of phospholipase activity. In the next step of the study, the Gaussian Process Regression (GPR) model accurately predicted bile tolerance and acid parameters with a high R² of 0.99 and minimal Mean Absolute Percentage Error (MAPE) values of 0.33 % and 0.21 %, respectively. The residual errors showed a normal distribution, indicating reliable and consistent predictions. Overall, <em>Lpb. pentosus</em> 6MMI represents a valuable candidate for further investigation in probiotic development and biofilm management strategies.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"9 ","pages":"Article 100255"},"PeriodicalIF":5.9,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143100578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aqueous extracts of Moringa oleifera and Cinnamomum cassia as promising sources of antibiofilm compounds against mucoid and small colony variants of Pseudomonas aeruginosa and Staphylococcus aureus","authors":"Eduarda Silva ,&nbsp;Pedro Ferreira-Santos ,&nbsp;José A. Teixeira ,&nbsp;Maria Olivia Pereira ,&nbsp;Cristina M.R. Rocha ,&nbsp;Ana Margarida Sousa","doi":"10.1016/j.bioflm.2024.100250","DOIUrl":"10.1016/j.bioflm.2024.100250","url":null,"abstract":"<div><div>Bacterial biofilms formed by <em>Staphylococcus aureus</em> and <em>Pseudomonas aeruginosa</em> pose significant challenges in treating cystic fibrosis (CF) airway infections due to their resistance to antibiotics. New therapeutic approaches are urgently needed to treat these chronic infections. This study aimed to investigate the antibiofilm potential of various plant extracts, specifically targeting mucoid and small colony variants of <em>P. aeruginosa</em> and <em>S. aureus</em> and strains. Moreover, it aimed to gain insights into the mechanisms of action and the potential phytochemicals responsible for antibiofilm activity. Solid-liquid extractions were performed on seven biomasses using water and ethanol (70 and 96 %) under controlled conditions, resulting in 21 distinct plant extracts. These extracts were evaluated for extraction yield, antioxidant activity, phenolic content, chemical composition by HPLC-TOF-MS, and antibiofilm activity using a 96-well plate assay, followed by crystal violet staining, bacterial adhesion assessment, and brightfield microscopy. Our findings revealed that aqueous extracts exhibited the highest inhibition of biofilm formation, with cinnamon bark and moringa seeds showing strong antibiofilm activity against both bacterial species. Brightfield microscopy confirmed that these extracts effectively inhibited biofilm formation. Chemical analysis identified key bioactive compounds, including moringin, benzaldehyde, coumarin, and quinic acid, which likely contribute to the observed antibiofilm effects. Recognizing that the antibiofilm properties of moringin, a common compound in both moringa seed and cinnamon bark extracts, remain underexplored, we conducted potential target identification via PharmMapper and molecular docking analyses to provide a foundation for future research. Computational analyses indicated that moringin might inhibit aspartate-semialdehyde dehydrogenase in <em>P. aeruginosa</em> and potentially interact with an unknown target in <em>S. aureus</em>. In conclusion, moringa seed and cinnamon bark extracts demonstrated significant potential for developing new therapies targeting biofilm-associated infections in CF. Further studies are needed to validate the computational predictions, identify the bacterial targets, and elucidate the precise mechanisms behind moringin's antibiofilm activity, which is likely the potential key contributor to the observed activity of the moringa and cinnamon bark extracts.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"9 ","pages":"Article 100250"},"PeriodicalIF":5.9,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11772965/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143061676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Key bacterial vaginosis-associated bacteria influence each other's growth in biofilms in rich media and media simulating vaginal tract secretions","authors":"Lúcia G.V. Sousa ,&nbsp;Christina A. Muzny ,&nbsp;Nuno Cerca","doi":"10.1016/j.bioflm.2024.100247","DOIUrl":"10.1016/j.bioflm.2024.100247","url":null,"abstract":"<div><div>Bacterial vaginosis (BV) is a very common gynaecologic condition affecting women of reproductive age worldwide. BV is characterized by a depletion of lactic acid-producing <em>Lactobacillus</em> species and an increase in strict and facultative anaerobic bacteria that develop a polymicrobial biofilm on the vaginal epithelium. Despite multiple decades of research, the etiology of this infection is still not clear. However, some BV-associated bacteria (BVAB) may play a key role in the development of this infection, namely <em>Gardnerella</em> species, <em>Prevotella bivia</em>, and <em>Fannyhessea vaginae</em>. In this work, we aimed to characterize the growth of these three species in a rich medium and in a medium simulating vaginal tract secretions (mGTS). We first assessed planktonic growth in New York City (NYCIII) medium and mGTS and observed that the three species showed distinct capacities to grow in the two media. Surprisingly, despite the ability of all three species to grow in single-species in NYCIII, in a triple-species consortium <em>P. bivia</em> was not able to increase its concentration after 48 h, as assessed by qPCR. Furthermore, when using the more restrictive mGTS media, <em>G. vaginalis</em> was the only BVAB able to grow in the triple-species consortia. Interestingly, we found that <em>P. bivia</em> growth in NYCIII was influenced by the cell-free supernatant (CFS) of <em>F. vaginae</em> and by the CFS of <em>G. vaginalis</em> in mGTS. This antimicrobial activity appears to happen due to the acidification of the media. Single- and triple-species biofilms were then formed, and the growth of each species was further quantified by qPCR. While <em>G. vaginalis</em> had a high capacity to form biofilms in both media, <em>F. vaginae</em> and <em>P. bivia</em> biofilm growth was favored when cultured in rich media. Differences were also found in the structure of triple-species biofilms formed in both media, as assessed by confocal laser scanning microscopy. In conclusion, while all three species were able to grow in single-species biofilms in rich media, in mGTS the growth of <em>G. vaginalis</em> was essential for incorporation of the other species in the biofilm.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"9 ","pages":"Article 100247"},"PeriodicalIF":5.9,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11773214/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143061677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aspartic acid unveils as antibiofilm agent and tobramycin adjuvant against mucoid and small colony variants of Pseudomonas aeruginosa isolates in vitro within cystic fibrosis airway mucus","authors":"Rosana Monteiro ,&nbsp;Ana Margarida Sousa ,&nbsp;Maria Olívia Pereira","doi":"10.1016/j.bioflm.2024.100252","DOIUrl":"10.1016/j.bioflm.2024.100252","url":null,"abstract":"<div><div>Antibiotics are central to managing airway infections in cystic fibrosis (CF), yet current treatments often fail due to the presence of <em>Pseudomonas aeruginosa</em> biofilms, settling down the need for seeking therapies targeting biofilms. This study aimed to investigate the antibiofilm activity of aspartic acid and its potential as an adjuvant to tobramycin against <em>P. aeruginosa</em> biofilms formed by mucoid and small colony variant (SCV) tobramycin tolerant strain. We assessed the effect of aspartic acid on both surface-attached and suspended <em>P. aeruginosa</em> biofilms within CF artificial mucus and investigated the synergistic impact of combining it with non-lethal tobramycin concentrations. Our findings showed that aspartic acid inhibited planktonic <em>P. aeruginosa</em> without affecting its viability and prevented biofilm formation by hindering bacterial adhesion or interfering with EPS production, depending on the experimental conditions. In CF mucus, aspartic acid significantly reduced bacterial growth, with the highest inhibition observed when combined with tobramycin, showing notable effects against the mucoid and tolerant SCV strain. Despite these reductions, <em>P. aeruginosa</em> repopulated the mucus within 24 h of stress withdrawal. Additional strategies, including delayed tobramycin application and a second dose of co-application of aspartic acid and tobramycin were explored to address bacterial survival and recovery. Although none of the strategies eradicated <em>P. aeruginosa</em>, the second co-application resulted in slower bacterial recovery rates.</div><div>In conclusion, this study highlighted aspartic acid as an effective antibiofilm agent and demonstrated for the first time its potential as an adjuvant to tobramycin. The combined use of aspartic acid and tobramycin offers a promising advancement in CF therapeutics, particularly against <em>P. aeruginosa</em> biofilms formed by mucoid and SCV strains, mitigating their antibiotic resistance.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"9 ","pages":"Article 100252"},"PeriodicalIF":5.9,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11759549/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143048929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}