Biofilm最新文献

{"title":"Transient cyanobacteria drive hydrostatic photogranulation but disappear during microbial succession","authors":"Sandra Galea-Outón ,&nbsp;Jérôme Hamelin,&nbsp;Kim Milferstedt","doi":"10.1016/j.bioflm.2025.100339","DOIUrl":"10.1016/j.bioflm.2025.100339","url":null,"abstract":"<div><div>Photogranulation transforms activated sludge into spatially organized photogranules, yet the role and fate of cyanobacterial strains that trigger this process remain poorly understood. Here, we tested the ability of seven strains of filamentous cyanobacteria to induce photogranule or mat morphotypes in replicated hydrostatic incubations. Despite successful granulation in all replicates when granule-forming strains were added, sequencing revealed that these keystone cyanobacteria responsible for photogranulation were outcompeted during community succession and absent from mature photogranules. A time-series experiment demonstrated that the added granule-forming strain <em>Geitlerinema</em> sp. A4 dominated the cyanobacterial community early on but was gradually replaced by mat-forming taxa, such as <em>Tychonema</em> and <em>Planktothrix</em>. Nevertheless, the granule morphotype persisted even after the founder strain vanished. These findings highlight that transiently dominant organisms can act as microbial engineers, steering ecosystem trajectories without remaining in the final community. This study refines our understanding of microbial succession and has practical implications for selecting the inoculum in biotechnological processes using photogranules.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"11 ","pages":"Article 100339"},"PeriodicalIF":4.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145665719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bioelectrochemical detection of viable but non-culturable bacterial cells on screen-printed carbon electrodes","authors":"Opeyemi Temitope Otemoye ,&nbsp;Sadia Nawab ,&nbsp;Feifeng Zhong ,&nbsp;Junyan Liu ,&nbsp;Alessandro Mattedi ,&nbsp;Paulo Debiagi ,&nbsp;Loh Teng-Hern Tan ,&nbsp;Kim R. Hardie ,&nbsp;Zhenbo Xu ,&nbsp;Enrico Marsili","doi":"10.1016/j.bioflm.2026.100354","DOIUrl":"10.1016/j.bioflm.2026.100354","url":null,"abstract":"<div><div>Bacterial cells in a viable but non-culturable (VBNC) state are metabolically active, but cannot be cultivated using a routine growth medium, which poses a challenge to identifying VBNC contamination in food and the health sector. Non-growth assays for VBNC identification based on membrane integrity and metabolic monitoring are either costly or lead to ambiguous results. Nucleic acid (DNA and RNA) amplification techniques are effective, but their higher cost and complexity prevent routine applications. Bioelectrochemical assays might be a viable alternative for VBNC detection, due to their low cost and rapid analysis time. However, conventional bioelectrochemical methods, in which electrodes are polarized at constant electrochemical potential, are not suitable for monitoring planktonic non-growing cells like VBNC.</div><div>To circumvent this issue, culturable and VBNC <em>Pseudomonas aeruginosa</em> cells were embedded in hydroxyethyl cellulose (HEC) coating and exposed to alternated cathodic and anodic potentials for a short-time. The resulting current output was interpreted in terms of charge/discharge of the bacterial membrane at the polarized electrode, which is a proxy for bacterial viability. <em>P. aeruginosa</em> cells were induced into the VBNC state by either UV-C or NaOCl. In the presence of 5 mM K₃[Fe(CN)₆] and 20 mM glucose, the current output correlates inversely with the VBNC cells concentration. For cells inactivated by heat or 4% paraformaldehyde, the current output was not significantly different from the blank electrode, indicating the ability of the proposed bioelectrochemical method to detect changes in cellular viability before the loss of culturability.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"11 ","pages":"Article 100354"},"PeriodicalIF":4.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146173561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SET-M33 loaded biosynthesized cellulose as effective protection against S. aureus biofilm formation","authors":"Sajad Mohammadi ,&nbsp;Alessia Maranesi ,&nbsp;Adrianus C.J.M. de Bruijn ,&nbsp;Ismael Castañon ,&nbsp;Piotr Gierlich ,&nbsp;Chiara Falciani ,&nbsp;Alessandro Pini ,&nbsp;Heleen M.M. van Beusekom ,&nbsp;Aldo Ferrari ,&nbsp;Wendy W.J. Unger","doi":"10.1016/j.bioflm.2026.100351","DOIUrl":"10.1016/j.bioflm.2026.100351","url":null,"abstract":"<div><div><em>Staphylococcus aureus</em> is the most common pathogen responsible for postoperative infections associated with cardiac implantable electronic devices (CIEDs), primarily due to its biofilm-forming capability on implant substrates<em>.</em> Protective envelopes, which sustain the local elution of antibiotics, significantly reduce the risk of CIED infection and biofilm formation. However, they are not equipped to counteract emerging bacterial resistance to antibiotics. Antimicrobial peptides (AMPs) can effectively erase contaminating bacteria, without eliciting resistance.</div><div>Here, we explored the antimicrobial efficacy of biosynthesized cellulose (BC), a natural biopolymer used in protective envelopes, in combination with two synthetic AMPs: SET-M33D and Mastoparan X (MPX). The BC/AMPs combination inhibited bacterial attachment and subsequent biofilm formation significantly better than native BC or AMP coated titanium substrates, as revealed by full factorial design (FFD) experiments. The outcomes of FFD were used to develop a regression model that estimates the interaction between influential parameters and their impacts on response value. Furthermore, SEM imaging confirmed the superior antibiofilm activity of BC/SET-M33D compared to BC/MPX. We demonstrated that the protective function against <em>S. aureus</em> ATCC29213 may be linked to the downregulation of the biofilm associated gene <em>icaA</em>.</div><div>The results reported demonstrate the feasibility of exploiting BC as AMP carrier for inhibiting biofilm formation in conditions relevant to deployment of CIEDs. While further in vivo evaluation is needed, this approach may offer a promising path to address antimicrobial resistance in the management of post-operative infections associated with CIED implant.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"11 ","pages":"Article 100351"},"PeriodicalIF":4.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146173634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental evolution in the cystic fibrosis chemical environment reveals early TCA cycle flux as a central regulator of Mycobacterium abscessus biofilm formation","authors":"Yu-Hao Wang ,&nbsp;Isabelle D'Amico ,&nbsp;Jocelyn Whalen ,&nbsp;Steven J. Mullett ,&nbsp;Stacy L. Gelhaus ,&nbsp;Vaughn S. Cooper ,&nbsp;Catherine R. Armbruster ,&nbsp;William H. DePas","doi":"10.1016/j.bioflm.2025.100343","DOIUrl":"10.1016/j.bioflm.2025.100343","url":null,"abstract":"<div><div><em>Mycobacterium abscessus</em> (MAB) is an emerging opportunistic pathogen that can cause severe, recalcitrant pulmonary infections in susceptible groups, including people with cystic fibrosis (CF). MAB forms biofilms during human infection and in environmental reservoirs such as household plumbing systems, and biofilm formation renders MAB more drug tolerant. However, our limited understanding of the regulatory systems governing mycobacterial biofilm formation undercuts our ability to disperse MAB biofilms and potentially increase treatment efficacy. Using experimental evolution, we demonstrate that selective pressure from synthetic cystic fibrosis sputum medium (SCFM1) drives the emergence of evolved MAB lineages that more readily aggregate in different environmental conditions. Whole-genome sequencing identified mutations in genes coding for two putative IclR family transcriptional regulators, which we named MraA and MraB, as responsible for the increase in aggregation. Using RNA-seq, we revealed that MraA and MraB share a regulon composed largely of genes involved in the early tricarboxylic acid (TCA) cycle and glutamate metabolism. Targeted metabolomic analysis confirmed that both mutants had increased levels of TCA cycle intermediates citrate/isocitrate and α-ketoglutarate (AKG), suggesting that in WT both MraA and MraB suppress flux through those metabolites. We found we could increase both citrate/isocitrate and AKG pools in WT MAB by supplementing SCFM1 with acetate, thereby increasing biofilm formation without increasing expression of the MraA/B regulon and demonstrating a specific causal relationship between those metabolites and biofilm formation. Finally, we show that acetate-induced, agar-suspended biofilms confer antibiotic tolerance. Altogether, we demonstrate how MAB carbon flux can be redirected by selective pressures in a CF sputum-like chemical environment to increase biofilm formation and drug tolerance. We propose a model in which MraA and MraB control flux of citrate/isocitrate/AKG and thereby feed into a metabolism-based biofilm regulatory system in MAB.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"11 ","pages":"Article 100343"},"PeriodicalIF":4.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145926550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a high-resolution multiplex qPCR method to profile microbial consortia in spaceflight water recovery systems","authors":"Amber Dowell Busboom ,&nbsp;Jiseon Yang ,&nbsp;Taylor M. Ranson ,&nbsp;Cheryl A. Nickerson ,&nbsp;Evan G. Ortiz ,&nbsp;Robert J.C. McLean","doi":"10.1016/j.bioflm.2026.100349","DOIUrl":"10.1016/j.bioflm.2026.100349","url":null,"abstract":"<div><div>A key component of life support on the International Space Station (ISS) is the Water Recovery System (WRS), which recycles and disinfects urine, other wastewater, and humidity condensate for use as potable water. A resident mixed-species bacterial population has persisted in the WRS, upstream from the disinfection components, despite various microbial control methods. Five bacterial species (<em>Pseudomonas aeruginosa, Burkholderia contaminans</em>, <em>Methylobacterium fujisawaense, Ralstonia insidiosa,</em> and <em>Cupriavidus metallidurans</em>) have been regularly isolated from the WRS and have a propensity to form biofilms, which can reduce susceptibility to antimicrobial treatments. WRS organisms have been associated with biofouling and potential corrosion of valves and filtration components. Currently, microbial monitoring on the ISS requires samples to be collected and sent back to Earth for culture-based analysis, a process that can take months, given the constraints of spacecraft scheduling. Culture-independent monitoring could be established on the ISS and other spacecraft, thereby enabling rapid estimates of microbial population density and individual species’ susceptibility to disinfection. This technology will be critical in future missions beyond low Earth orbit, when access to reference labs is not possible. Here, we report on the development and validation of a multiplex quantitative Polymerase Chain Reaction (qPCR) method to identify and quantify members of a five species model biofilm community acquired from the ISS. Species-specific primers and probes detect organisms to an estimated detection limit of 10⁴–10⁶ CFU and detect the specific targeting of <em>C. metallidurans</em> by ampicillin when overall population levels were not significantly changed.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"11 ","pages":"Article 100349"},"PeriodicalIF":4.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146173636","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Staphylococcal persistence and biofilm resistance in bone-anchored hearing systems: Clinical impact","authors":"Marsel Ganeyev ,&nbsp;Liliana Morales-Laverde ,&nbsp;Maria Hoffman ,&nbsp;Malou Hultcrantz ,&nbsp;Anders Palmquist ,&nbsp;Peter Thomsen ,&nbsp;Martin L. Johansson ,&nbsp;Margarita Trobos","doi":"10.1016/j.bioflm.2025.100342","DOIUrl":"10.1016/j.bioflm.2025.100342","url":null,"abstract":"<div><div>Persistent inflammation and infection, often linked to staphylococcal colonization, affect bone-anchored hearing system (BAHS) outcomes. Although antibiotics are often used to treat skin complications, the roles of biofilms and antimicrobial resistance (AMR) in clinical success remain unclear. This clinical prospective study characterized biofilm formation and antibiotic resistance in <em>Staphylococcus</em> spp. from BAHS patients, and examined associations with inflammation, pain, and hygiene. Adults eligible for BAHS were prospectively enrolled at a tertiary university hospital in Sweden during 2014–2015. Fifteen patients were followed clinically and microbiologically at surgery, 3- and 12- months. Abutment, peri-abutment exudate and soft-tissue samples were cultured. Fifty-seven <em>Staphylococcus</em> spp. isolates underwent biofilm phenotyping (Crystal Violet, Congo Red), antimicrobial susceptibility testing (minimum inhibitory concentration [MIC], minimum biofilm eradication concentration [MBEC]) and whole-genome sequencing (lineage, AMR and virulence genes). Clinical status was scored (Holgers, pain, debris). Individual patients harbored the same staphylococcal clone on abutment, exudate, and tissue for 12 months. <em>S. aureus</em> was more prevalent in patients with inflammation (Holgers score &gt;0), <em>S. epidermidis</em> correlated with pain, and slime production was associated with debris accumulation. Overall, 56 % of isolates showed resistance to fusidic acid, and 11–34 % carried tetracycline resistance genes. <em>S. epidermidis</em> carried multidrug resistance genes (beta-lactams, tetracycline, sulfamethoxazole, fosfomycin), and resistance increased under biofilm conditions (MBEC &gt; MIC). The <em>ica</em> operon was detected in all <em>S. aureus</em> and <em>S. epidermidis</em> ST7, ST297, ST749 and ST278. These findings indicate that staphylococci from BAHS exhibit persistent colonization, diverse clonal lineages, and high biofilm-associated AMR. Early microbial diagnostics and biofilm-targeted strategies, alongside cautious use of topical antibiotics, may improve outcomes.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"11 ","pages":"Article 100342"},"PeriodicalIF":4.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145791266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inactivation of Cysteine Synthase CysK-A enhances flocculation, biofilm formation, and sensitivity to oxidative stress in Azospirillum brasilense Sp7","authors":"Job Herrera-Galindo ,&nbsp;Clara Andrea Alcantara-Rosales ,&nbsp;Oscar Mateo Ojeda Jr. ,&nbsp;María Luisa Xiqui-Vázquez ,&nbsp;Claudia Mancilla-Simbro ,&nbsp;Sandra Reyes-Carmona ,&nbsp;Beatriz Eugenia Baca ,&nbsp;Alberto Ramírez-Mata","doi":"10.1016/j.bioflm.2025.100335","DOIUrl":"10.1016/j.bioflm.2025.100335","url":null,"abstract":"<div><div>Cysteine biosynthesis is a critical metabolic pathway for bacterial physiology. However, the full impact on the lifestyle of the plant-beneficial bacterium <em>Azospirillum brasilense</em> Sp7 is not completely understood. Our previous work identified a cysteine synthase A (CysK-A) as a key enzyme in cysteine synthesis in <em>A. brasilense</em> Sp7, but its inactivation did not lead to cysteine auxotrophy, suggesting functional redundancy in this type of enzyme. Here, we comprehensively characterized an <em>A. brasilense</em> AR <em>cysK</em>-A mutant, revealing a multifaceted phenotype that highlights the indispensable role of CysK-A. The <em>cysK</em>-A mutant exhibited a growth defect that was rescued by genetic and chemical complementation, underscoring the importance of <em>de novo</em> cysteine synthesis for optimal metabolic fitness. Furthermore, the <em>cysK</em>-A mutant displayed a striking hyper-aggregative behavior, characterized by significantly enhanced flocculation, biofilm formation, and exopolysaccharide production. Confocal microscopy revealed an abundance of ovoid, cyst-like cells. This transition toward a sessile lifestyle, induced by cysteine limitation stress, correlated with the intracellular accumulation of cyclic-di-GMP, as determined by a c-di-GMP biosensor assay. Additionally, the <em>cysK</em>-A mutant exhibited increased sensitivity to exogenous hydrogen peroxide stress, a deficiency that was restored by <em>cysK</em>-A complementation. The mutation also led to enhanced adhesion to radish seeds; however, it did not result in statistically significant differences in overall radish seedling colonization after seven days, possibly due to compensatory mechanisms. Collectively, our findings establish CysK-A as crucial for optimal growth, stress tolerance, and the regulation of aggregative behaviors in <em>A. brasilense</em> Sp7, providing insights into the adaptive strategies employed by this important plant-associating bacterium.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"11 ","pages":"Article 100335"},"PeriodicalIF":4.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145926549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Amino acid starvation and iron limitation facilitate the biofilm formation of Klebsiella pneumoniae within urine","authors":"Xinming Pan ,&nbsp;Yinchu Zhu ,&nbsp;Yan Zhang ,&nbsp;Jie Zhao ,&nbsp;Xing Gao ,&nbsp;Caiying Li ,&nbsp;Yong Yu ,&nbsp;Jiale Ma","doi":"10.1016/j.bioflm.2026.100347","DOIUrl":"10.1016/j.bioflm.2026.100347","url":null,"abstract":"<div><div>Biofilm formation is a critical virulence mechanism in pathogens such as <em>Klebsiella pneumoniae</em>, a Gram-negative, encapsulated bacterium that has emerged as a zoonotic threat capable of infecting both humans and animals. Its biofilm-forming ability is closely associated with catheter-related and urinary tract infections. Given its potential to cross species barriers and cause significant public health concern, elucidating the environmental cues and conserved molecular pathways driving biofilm formation is essential for developing cross-species prevention strategies. Here we found that <em>K. pneumoniae</em> exhibited significantly greater biofilm-forming efficiency in urine than in nutrient-rich medium under comparable biomass conditions. Transposon-insertion sequencing (Tn-seq) identified 19 fitness genes essential for optimal growth in urine, most involved in the <em>de novo</em> biosynthesis of amino acids, particularly arginine, methionine, and isoleucine. Urine represents an amino acid-starved (AAS) environment for <em>K. pneumoniae</em>, modulating c-di-GMP signaling to promote biofilm formation. Eight diguanylate cyclase (DGC, c-di-GMP synthesis) genes, four phosphodiesterase (PDE, c-di-GMP degradation) genes, and four DGC + PDE genes were significantly regulated in response to urine. Furthermore, transcriptomic analysis comparing <em>K. pneumoniae</em> grown in urine with that grown in M9 medium revealed significant activation of genes associated with exopolysaccharide (EPS) biosynthesis, including those encoding lipopolysaccharides (LPS), capsules, peptidoglycan, and enterobacterial common antigen (ECA). Notably, <em>K. pneumoniae</em> increases EPS biosynthesis under the iron-limited conditions in urine, further promoting biofilm development. In conclusion, AAS-mediated c-di-GMP signaling and iron limitation are key drivers of biofilm formation by <em>K. pneumoniae</em> in urine, providing mechanistic insights that may guide strategies to disrupt biofilm formation.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"11 ","pages":"Article 100347"},"PeriodicalIF":4.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146022653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Directed evolution of phage Romulus in biofilm-embedded Staphylococcus aureus: mutations in baseplate proteins enhanced its antibiofilm activity","authors":"Claudia Campobasso ,&nbsp;Pauline Henderix ,&nbsp;Ekaterina Jalomo-Khayrova ,&nbsp;Sara Bolognini ,&nbsp;Gert Bange ,&nbsp;Rob Lavigne ,&nbsp;Arianna Tavanti ,&nbsp;Jeroen Wagemans ,&nbsp;Mariagrazia Di Luca","doi":"10.1016/j.bioflm.2026.100345","DOIUrl":"10.1016/j.bioflm.2026.100345","url":null,"abstract":"<div><div>The ability of <em>Staphylococcus aureus</em> to form biofilm and the emergence of multidrug-resistant strains make staphylococcal infections often chronic and difficult to treat. To face these challenges, alternative or adjunct strategies to antibiotics are urgently required. In this context, phage therapy gained renewed interest as promising approach to target multidrug-resistant bacteria. To enhance their efficacy as natural phages, they can undergo directed evolution via serial host passages. To date, most protocols focus on planktonic cultures, while the effects towards biofilm-targeted evolution remain poorly explored.</div><div>Our study aims at investigating the potential of a new directed evolution protocol designed to specifically enhance the efficacy of phage Romulus to target staphylococcal sessile communities and to identify whether specific phage proteins are involved in this process.</div><div>The method involved 31 serial passages with a two-step incubation: 1 h for phage adsorption and infection, followed by 8 h for its amplification. Mutant phages were isolated, sequenced, and phenotypically characterised.</div><div>Mutations emerged in two baseplate proteins (gp54 and gp58), involved in host adsorption. Three mutants (R31, R31p2, R31p5) showed enhanced bactericidal activity against planktonic cells and improved efficacy against biofilm, achieving up to a 4-log₁₀ reduction. While their host range remained consistent with the wildtype, phage Romulus mutants exhibited higher efficiency of plating against the nine out of 21 sensitive <em>S. aureus</em> strains.</div><div>Overall, our results underscore the potential of biofilm-adapted phages to improve phage efficacy towards both planktonic and sessile cells, without impacting on the phage host range. The analysis of mutations suggested that the baseplate plays a crucial role in targeting biofilm-embedded cells, even if further investigation is necessary to explain the molecular basis responsible for the enhanced lytic efficacy.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"11 ","pages":"Article 100345"},"PeriodicalIF":4.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146022654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fluorene derivatives as potent antifungal and antibiofilm agents against fluconazole-resistant Candida albicans","authors":"Oluwatosin Oluwaseun Faleye ,&nbsp;Amra Yunus ,&nbsp;Jin-Hyung Lee,&nbsp;Jintae Lee","doi":"10.1016/j.bioflm.2025.100319","DOIUrl":"10.1016/j.bioflm.2025.100319","url":null,"abstract":"<div><div><em>Candida albicans</em> ranks as one of the most common causes of fungal sepsis in hospitalized patients around the world with an increasing mortality rate. The current antifungal drugs in use face several limitations including fungal resistance due to biofilm formation. This has complicated the treatment landscape, necessitating the need for continued search for effective therapeutic options against drug-resistant <em>C. albicans</em> threats. Therefore, this study investigated eighteen fluorene derivatives for their antifungal and antibiofilm potential against <em>C. albicans</em>. Two fluorene derivatives namely: 9,9-bis(4-hydroxyphenyl) fluorene (BHPF) and fluorene-9-acetic acid (FAA) were identified as potential inhibitors of <em>Candida</em> biofilms, achieving 97 % and 89 % inhibition at 10 μg/mL. Microscopic studies also confirmed their antibiofilm efficacy, with BHPF demonstrating activities comparable to amphotericin B. Furthermore, BHPF inhibited planktonic cell growth at concentration as low as 5 μg/mL. Both BHPF and FAA exhibited fungicidal activity and also inhibited <em>C. albicans</em> virulence factors such as cell aggregation and hyphal formation. Notably, neither compound showed propensity for resistance development over 15 passages. Additionally, toxicity evaluations in both plant and <em>Caenorhabditis elegans</em> model revealed non-to mild toxicity, and the ADMET prediction also satisfied the criteria for drug-likeliness. The results of this multifaceted investigation highlight the potential of BHPF and FAA as novel antifungal agents targeting <em>C. albicans</em> infections and biofilm-related challenges.</div></div>","PeriodicalId":55844,"journal":{"name":"Biofilm","volume":"10 ","pages":"Article 100319"},"PeriodicalIF":4.9,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145219001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}