Biofilm最新文献

{"title":"Cellulophaga algicola alginate lyase and Pseudomonas aeruginosa Psl glycoside hydrolase inhibit biofilm formation by Pseudomonas aeruginosa CF2843 on three-dimensional aggregates of lung epithelial cells","authors":"Neetu ,&nbsp;Shilpee Pal ,&nbsp;Srikrishna Subramanian ,&nbsp;T.N.C. Ramya","doi":"10.1016/j.bioflm.2025.100265","DOIUrl":"10.1016/j.bioflm.2025.100265","url":null,"abstract":"<div><div><em>Pseudomonas aeruginosa</em> is an opportunistic pathogen that produces a biofilm containing the polysaccharides, alginate, Psl, and Pel, and causes chronic lung infection in cystic fibrosis patients. Others and we have previously explored the use of alginate lyases in inhibiting <em>P. aeruginosa</em> biofilm formation on plastic and lung epithelial cell monolayers. We now employ a more physiologically representative model system, i.e., three-dimensional aggregates of A549 lung epithelial cells cultured under conditions of microgravity in a rotary cell culture system to mimic the natural lung environment, and a previously isolated clinical strain, <em>Pseudomonas aeruginosa</em> CF2843 that we engineered by transposon-mediated integration to express Green Fluorescent Protein and for which we also report the complete genome sequence. Immunostaining and lectin binding studies indicated that the three-dimensional cell aggregates harbored sialylated and fucosylated epitopes as well as Muc1, Muc5Ac, and β-catenin on their surfaces, suggestive of mucin secretion and the presence of tight junctions, hallmark features of lung epithelial tissue. Using this validated model system with confocal microscopy and viable bacterial counts as readouts, we demonstrated that <em>Cellulophaga algicola</em> alginate lyase and <em>Pseudomonas aeruginosa</em> Psl glycoside hydrolase, but not <em>Pseudomonas aeruginosa</em> Pel glycoside hydrolase, inhibit biofilm formation by <em>Pseudomonas aeruginosa</em> on three-dimensional lung epithelial cell aggregates.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"9 ","pages":"Article 100265"},"PeriodicalIF":5.9,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143478545","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":"Immune-based strategies for the treatment of biofilm infections","authors":"Zachary Van Roy,&nbsp;Tammy Kielian","doi":"10.1016/j.bioflm.2025.100264","DOIUrl":"10.1016/j.bioflm.2025.100264","url":null,"abstract":"<div><div>Biofilms are bacterial communities surrounded by a polymeric matrix that can form on implanted materials and biotic surfaces, resulting in chronic infection that is recalcitrant to immune- and antibiotic-mediated clearance. Therefore, biofilm infections present a substantial clinical challenge, as treatment often involves additional surgical interventions to remove the biofilm nidus, prolonged antimicrobial therapy to clear residual bacteria, and considerable risk of treatment failure or infection recurrence. These factors, combined with progressive increases in antimicrobial resistance, highlight the need for alternative therapeutic strategies to circumvent undue morbidity, mortality, and resource strain on the healthcare system resulting from biofilm infections. One promising option is reprogramming dysfunctional immune responses elicited by biofilm. Here, we review the literature describing immune responses to biofilm infection with a focus on targets or strategies ripe for clinical translation. This represents a complex and dynamic challenge, with context-dependent host-pathogen interactions that differ across infection models, microenvironments, and individuals. Nevertheless, consistencies among these variables exist, which could facilitate the development of immune-based strategies for the future treatment of biofilm infections.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"9 ","pages":"Article 100264"},"PeriodicalIF":5.9,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143509191","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":"A simulated microgravity biofilm reactor with integrated microfabricated sensors: Advancing biofilm studies in near-space conditions","authors":"Haley M. Ketteler ,&nbsp;Erick L. Johnson ,&nbsp;Matthew McGlennen ,&nbsp;Markus Dieser ,&nbsp;Christine M. Foreman ,&nbsp;Stephan Warnat","doi":"10.1016/j.bioflm.2025.100263","DOIUrl":"10.1016/j.bioflm.2025.100263","url":null,"abstract":"<div><div>Studying biofilms in a microgravity environment currently relies on one of two scenarios, collecting planktonic aggregates in rotating wall vessels or performing experiments in the microgravity environment of space on the International Space Station. While informative techniques, both have their limitations when studying surface-attached microbial communities. A simulated microgravity biofilm reactor (SMBR) was developed to study biofilms in microgravity, coupled with the integration of microfabricated sensors for internal system monitoring. The establishment of simulated microgravity was demonstrated through computational fluid dynamic modelling revealing low fluid shear stress conditions (&lt;1 mPa) throughout the reactor and on the wall surface. Microfabricated resistance temperature devices integrated in the reactor walls confirmed the capability for continuous sensor measurements during operation with the ability to perform traditional microbiology analyses on the sensor surface following an experiment. Microbiological analyses established that there were no significant differences in biofilm growth between sensor and wall surfaces within the reactor. With the integration of defined sampling surfaces, the SMBR allows for in-depth biofilm analysis in a repeatable and accessible manner allowing for a greater understanding of the effects of microgravity on biofilm.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"9 ","pages":"Article 100263"},"PeriodicalIF":5.9,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143454000","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":"In vivo efficacy of a refillable intrawound drug delivery device in a sheep model of biofilm-compromised open fracture-related infection","authors":"Dustin Williams ,&nbsp;David Rothberg ,&nbsp;Walker Kay ,&nbsp;Lisa Nehring ,&nbsp;Robert Falconer ,&nbsp;Richard Tyler Epperson ,&nbsp;Brooke Kawaguchi ,&nbsp;Carolyn Ardizzone ,&nbsp;Brian Barnum ,&nbsp;Nicholas Ashton","doi":"10.1016/j.bioflm.2025.100262","DOIUrl":"10.1016/j.bioflm.2025.100262","url":null,"abstract":"<div><div>Open fracture-related infection challenges persist in healthcare. From the time open fractures were defined ∼50 years ago, infection rates have gone essentially unchanged. Contributing factors include compromised vasculature, biofilm, and stalled innovations in treatment and prophylaxis. In this study, we engineered and tested the efficacy of a refillable drug delivery device, the Purgo Pouch (Pouch), that sustains local, high dose intrawound antibiotic concentrations in wound sites. We hypothesized that it would manage biofilm-compromised open fracture-related infection better than clinical standards of care. Therapies were tested in a unique sheep model of long bone open fracture-related infection with compromised tissue and biofilm inocula of methicillin-resistant <em>Staphylococcus aureus</em>. Sheep (n = 5/group) were treated with IV vancomycin (10 days), gentamicin-loaded CaSO₄ beads (single application), or the Pouch (10 days) loaded with gentamicin alone or a triple antibiotic combination. At 21 days, sheep were euthanized and microbiological and histological data collected. Results indicated that the Pouch managed infection more effectively, reducing bioburden to &lt;10⁵ colony forming units (CFU)/sample, which was statistically significant compared to clinical standards, which failed to reduce bioburden to below 10⁵ CFU. The hypothesis was supported. The Pouch received Breakthrough Device Designation by the FDA, is being transitioned toward clinical trials, and is a potential solution to the long-standing problem of open fracture-related infection.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"9 ","pages":"Article 100262"},"PeriodicalIF":5.9,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143453999","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":"Early fibrin biofilm development in cardiovascular infections","authors":"Safae Oukrich ,&nbsp;Jane Hong ,&nbsp;Mariël Leon-Grooters ,&nbsp;Wiggert A. van Cappellen ,&nbsp;Johan A. Slotman ,&nbsp;Gijsje H. Koenderink ,&nbsp;Willem J.B. van Wamel ,&nbsp;Moniek P.M. de Maat ,&nbsp;Klazina Kooiman ,&nbsp;Kirby R. Lattwein","doi":"10.1016/j.bioflm.2025.100261","DOIUrl":"10.1016/j.bioflm.2025.100261","url":null,"abstract":"<div><div>The single most common microbe causing cardiovascular infections is <em>Staphylococcus aureus</em> (<em>S. aureus</em>). <em>S. aureus</em> produces coagulase that converts fibrinogen to fibrin, which is incorporated into biofilms. This process aids in adherence to intravascular structures, defense against the host immune system, and resistance to antimicrobial treatment. Despite its significance, fibrin formation in <em>S. aureus</em> biofilms remains poorly understood. Therefore, this study aimed to elucidate the early development of cardiovascular biofilms. Clinically isolated coagulase-positive <em>S. aureus</em> and coagulase-negative <em>Staphylococcus lugdunensis</em> (<em>S. lugdunensis</em>) from patients with cardiovascular infections, and a coagulase mutant <em>S. aureus</em> Δcoa, were grown in tryptic soy broth (TSB), Iscove's Modified Dulbecco's Medium (IMDM), and pooled human plasma, with or without porcine heart valves. Bacterial growth, metabolic activity, and bacterial fibrinogen utilization were measured over 24 h at 37 °C. Time-lapse confocal microscopy was used to visualize and track biofilm development. <em>S. aureus</em> exhibited more growth in TSB and human plasma than <em>S. lugdunensis</em> and <em>S. aureus</em> Δcoa, but showed similar growth in IMDM after 24 h. Peak metabolic activity for all isolates was highest in TSB and lowest in human plasma. The presence of porcine valves caused strain-dependent alterations in time to peak metabolic activity. Confocal imaging revealed fibrin-based biofilm development exclusively in the coagulase-producing <em>S. aureus</em> strains. Between 2 and 6 h of biofilm development, 74.9 % (p = 0.034) of the fibrinogen from the medium was converted to fibrin. Variations in fibrin network porosity and density were observed among different coagulase-producing <em>S. aureus</em> strains. Fibrin formation is mediated by <em>S. aureus</em> coagulase and first strands occurred within 3 h for clinical strains after exposure to human plasma. This study stresses the importance of experimental design given the bacterial changes due to different media and substrates and provides insights into the early pathogenesis of <em>S. aureus</em> cardiovascular biofilms.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"9 ","pages":"Article 100261"},"PeriodicalIF":5.9,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143419270","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":"Decoding interactions between biofilms and DNA nanoparticles","authors":"Alexandra Sousa ,&nbsp;Rutuparna Kulkarni ,&nbsp;Mona Johannessen ,&nbsp;Thorsten Wohland ,&nbsp;Nataša Škalko-Basnet ,&nbsp;Sybil Obuobi","doi":"10.1016/j.bioflm.2025.100260","DOIUrl":"10.1016/j.bioflm.2025.100260","url":null,"abstract":"<div><div>Biofilms present a great challenge in antimicrobial therapy due to their inherent tolerance to conventional antibiotics, promoting the need for advanced drug delivery strategies that improve therapy. While various nanoparticles (NPs) have been reported for this purpose, DNA-based NPs remain a largely unexploited resource against biofilm-associated infections. To fill this gap and to lay the groundwork for their potential therapeutic exploitation, we investigated the diffusion, penetration, and retention behaviors of three DNA-based nanocarriers —plain or modified—within <em>P. aeruginosa</em> biofilms. Watson-Crick base pairing or hydrophobic interactions mediated the formation of the plain NPs whilst electrostatic interaction enabled optimization of coated NPs via microfluidic mixing. We assessed the interactions of the nanocarriers with biofilm structures via Single Plane Illumination Microscopy – Fluorescence Correlation Spectroscopy (SPIM-FCS) and Confocal Laser Scanning Microscopy (CLSM). We demonstrate the impact of microfluidic parameters on the physicochemical properties of the modified DNA NPs and their subsequent distinct behaviors in the biofilm. Our results show that single stranded DNA micelles (ssDNA micelle) and tetrahedral DNA nanostructures (TDN) had similar diffusion and penetration profiles, whereas chitosan-coated TDN (TDN-Chit) showed reduced diffusion and increased biofilm retention. This is attributable to the relatively larger size and positive surface charge of the TDN-Chit NPs. The study shows first and foremost that DNA can be used as building block in drug delivery for antibiofilm therapeutics. Moreover, the overall behavioral findings are pivotal for the strategic selection of therapeutic agents to be encapsulated within these structures, possibly affecting the treatment efficacy. This research not only highlights the underexplored potential of DNA-based NPs in antibiofilm therapy but also advocates for further studies using different optimization strategies to refine these nanocarrier systems for targeted treatments in biofilm-related infections.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"9 ","pages":"Article 100260"},"PeriodicalIF":5.9,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143387471","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":"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}