Biofilm最新文献

{"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}

{"title":"Surfactin accelerates Bacillus subtilis pellicle biofilm development","authors":"Rune Overlund Stannius ,&nbsp;Sarah Fusco ,&nbsp;Michael S. Cowled ,&nbsp;Ákos T. Kovács","doi":"10.1016/j.bioflm.2024.100249","DOIUrl":"10.1016/j.bioflm.2024.100249","url":null,"abstract":"<div><div>Surfactin is a biosurfactant produced by many <em>B. subtilis</em> strains with a wide variety of functions from lowering surface tension to allowing motility of bacterial swarms, acting as a signaling molecule, and even exhibiting antimicrobial activities. However, the impact of surfactin during biofilm formation has been debated with variable findings between studies depending on the experimental conditions.</div><div>B. subtilis is known to form biofilms at the solid-air, the solid-medium, and the liquid-air interfaces, the latter of which is known as a pellicle biofilm. Pellicle formation is a complex process requiring coordinated movement to the liquid-air interface and subsequent cooperative production of biofilm matrix components to allow robust pellicle biofilm formation. This makes pellicle formation a promising model system for assaying factors in biofilm formation and regulation.</div><div>Here, we assayed the influence of surfactin and additional metabolites on the timing of pellicle biofilm formation. Using time-lapse imaging, we assayed pellicle formation timing in 12 <em>B. subtilis</em> isolates and found that one, MB9_B4, was significantly delayed in pellicle formation by approximately 10 h. MB9_B4 was previously noted to lack robust surfactin production. Indeed, deletion of surfactin synthesis in the other isolates delayed pellicle formation. Further, pellicle delay was rescued by addition of exogeneous surfactin. Testing reporters of biofilm-related gene expression revealed that induction of pellicle formation was caused by a combination of increased gene expression of one of the biofilm components and promotion of growth.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"9 ","pages":"Article 100249"},"PeriodicalIF":5.9,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11754971/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143030291","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":"Eicosapentaenoic acid as an antibiofilm agent disrupts mature biofilms of Candida albicans","authors":"Shuai Wang ,&nbsp;Shiwang Xie ,&nbsp;Tianmeng Li ,&nbsp;Jun Liu ,&nbsp;Peng Wang ,&nbsp;Yu Wang ,&nbsp;Li Gu ,&nbsp;Dan Luo ,&nbsp;Ming Wei","doi":"10.1016/j.bioflm.2024.100251","DOIUrl":"10.1016/j.bioflm.2024.100251","url":null,"abstract":"<div><div>The biofilm formation of <em>Candida albicans</em>, a major human fungal pathogen, represents a crucial virulence factor during candidiasis. Eicosapentaenoic acid (EPA), a polyunsaturated fatty acid, has emerged as a potential antibiofilm agent against <em>C</em>. <em>albicans</em>. Herein, we aim to investigate the antifungal effect of EPA (1 mM) on the mature biofilm of <em>C. albicans</em> and explore the underlying mechanism. Crystal violet and XTT assays showed that EPA exerted a strong inhibitory efficacy on preformed biofilms in <em>C. albicans</em>. Biofilm architecture and cell viability were observed using scanning electron microscopy and confocal laser scanning microscopy, indicating that EPA could block the yeast-to-hypha transition and damage the structure, thereby exhibiting antibiofilm activity. RNA sequencing analysis revealed that EPA treatment led to the downregulation of genes associated with hyphal formation and biofilm development. From the signaling pathway perspective, EPA regulated the <em>C. albicans</em> biofilms involving two signaling pathways, namely, Ras1-cAMP-PKA and Cek-MAPK pathways. Additionally, the EPA could effectively reduce the production of key messenger cAMP in the Ras1-cAMP-PKA pathway. Interestingly, in response to EPA, ergosterol biosynthesis-related genes were down-regulated, indicating EPA as antifungal agent might reduce the risk of developing drug resistance. The findings of this study highlight the potential of EPA as an alternative or adjunctive antibiofilm agent against <em>C. albicans</em>-related infections.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"9 ","pages":"Article 100251"},"PeriodicalIF":5.9,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11751545/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143025687","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":"Multipronged impact of environmental temperature on Staphylococcus aureus infection by phage Kayvirus rodi: Implications for biofilm control","authors":"Lucía Fernández ,&nbsp;Ana Catarina Duarte ,&nbsp;Andrea Jurado ,&nbsp;Laura Bueres ,&nbsp;Ana Rodríguez ,&nbsp;Pilar García","doi":"10.1016/j.bioflm.2024.100248","DOIUrl":"10.1016/j.bioflm.2024.100248","url":null,"abstract":"<div><div>Environmental cues sometimes have a direct impact on phage particle stability, as well as bacterial physiology and metabolism, having a profound effect on phage infection outcome. Here, we explore the impact of temperature on the interplay between phage <em>Kayvirus rodi</em> (phiIPLA-RODI) and its host, <em>Staphylococcus aureus</em>. Our results show that phiIPLA-RODI is a more effective predator at room (25 °C) compared to body temperature (37 °C) against planktonic cultures of several strains with varying degrees of phage susceptibility. This result differs from most known examples of temperature-dependent phage infection, in which optimum infection is correlated with the host growth rate. Further characterization of this phenomenon was carried out with strains IPLA15 and IPLA16, whose respective MICs were 7 log units and a 1-log unit higher at 37 °C than at 25 °C. Our results demonstrated that the phage also had a greater impact at room temperature during biofilm development and for the treatment of preformed biofilms. There was no difference in phage adsorption between the two temperatures for strain IPLA16. Conversely, adsorption of phiIPLA-RODI to IPLA15 was reduced at 37 °C compared to 25 °C. Moreover, confocal microscopy analysis indicated that the biofilm matrix of both strains has a greater content of PIA/PNAG at 37 °C than at 25 °C. Regarding infection parameters, we observed longer duration of the lytic cycle at 25 °C for both strains, and infection of IPLA15 by phiIPLA-RODI resulted in a smaller burst size at 37 °C than at 25 °C. Finally, we also found that the rate of phage resistant mutant selection was higher at 37 °C for both strains. Altogether, this information highlights the impact that bacterial responses to environmental factors have on phage-host interactions. Moreover, phage phiIPLA-RODI appears to be a highly effective candidate for biofilm disinfection at room temperature, while its efficacy in biofilm-related infections will require combination with other antimicrobials.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"9 ","pages":"Article 100248"},"PeriodicalIF":5.9,"publicationDate":"2024-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11751508/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143025710","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":"Cystic fibrosis and the clinical biofilm revolution A survey of the Danish CF Center's contribution","authors":"Niels Høiby","doi":"10.1016/j.bioflm.2024.100246","DOIUrl":"10.1016/j.bioflm.2024.100246","url":null,"abstract":"<div><h3>Background</h3><div>Biofilm infections are chronic infections which are difficult to diagnose. Biofilm infections are tolerant to antibiotics and the defense mechanisms of the host. Patients with the genetic disease cystic fibrosis (CF) produce viscid mucus in the respiratory tract and therefore suffer from chronic biofilm infections in their lungs and paranasal sinuses.</div><div>The most important microorganism is the mucoid phenotype of <em>Pseudomonas aeruginosa</em> which causes chronic biofilm infections in the lungs of CF patients and untreated patients succumb as children if they contact this biofilm infection.</div><div>Since CF patients are treated in CF Centers all over the world, it is possible to do longitudinal studies on epidemiology, pathophysiology, diagnosis, prevention and treatment of <em>P. aeruginosa</em> biofilm infection which is not possible if such patients are not followed in specialized centers.</div><div>This survey describes the research through several decades in the Danish CF Center in Copenhagen which have changed the epidemiology, treatment, prophylaxis and prognosis of CF patients worldwide. Based on these results ESCMID Guidelines for diagnosis and treatment of biofilm infections were published which have influenced biofilm research and treatment in other areas.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"9 ","pages":"Article 100246"},"PeriodicalIF":5.9,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11732244/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142985525","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}