title: Biofilm formation by multidrug resistant Escherichia coli ST131 is dependent on type 1 fimbriae and assay conditions.
abstract: Escherichia coli sequence type 131 (ST131) has emerged as a pandemic lineage of important multidrug resistant pathogens worldwide. Despite many studies examining the epidemiology of ST131, only a few studies to date have investigated the capacity of ST131 strains to form biofilms. Some of these studies have reported contrasting findings, with no specific ST131 biofilm-promoting factors identified. Here, we examined a diverse collection of ST131 isolates for in vitro biofilm formation in different media and assay conditions, including urine from healthy adult women. We found significant differences among strains and assay conditions, which offers an explanation for the contrasting findings reported by previous studies using a single condition. Importantly, we showed that expression of type 1 fimbriae is a critical determinant for biofilm formation by ST131 strains and that inhibition of the FimH adhesin significantly reduces biofilm formation. We also offer direct genetic evidence for the contribution of type 1 fimbriae in biofilm formation by the reference ST131 strain EC958, a representative of the clinically dominant H30-Rx ST131 subgroup. This is the first study of ST131 biofilm formation in biologically relevant conditions and paves the way for the application of FimH inhibitors in treating drug resistant ST131 biofilm infections.
authors.affiliation: School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland 4072, Australia Australian Infectious Disease Research Centre, University of Queensland, Brisbane, Queensland 4072, Australia Institute of Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove, Queensland 4059, Australia School of Biomedical Sciences, Queensland University of Technology, Kelvin Grove, Queensland 4059, Australia.
authors.forename: Sohinee
authors.initials: S
authors.lastname: Sarkar
authors.affiliation: Institute of Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove, Queensland 4059, Australia.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Vagenas
authors.affiliation: School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland 4072, Australia Australian Infectious Disease Research Centre, University of Queensland, Brisbane, Queensland 4072, Australia.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Schembri
authors.affiliation: Institute of Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove, Queensland 4059, Australia School of Biomedical Sciences, Queensland University of Technology, Kelvin Grove, Queensland 4059, Australia makrina.totsika@qut.edu.au.
authors.forename: Makrina
authors.initials: M
authors.lastname: Totsika
mesh_terms: D018830:Adhesins, Escherichia coli / Q000235:genetics / Q000378:metabolism; D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001437:Bacteriuria / Q000382:microbiology*; D018441:Biofilms / Q000254:growth & development*; D024901:Drug Resistance, Multiple, Bacterial; D004926:Escherichia coli / Q000145:classification / Q000187:drug effects* / Q000302:isolation & purification / Q000472:pathogenicity*; D004927:Escherichia coli Infections / Q000382:microbiology; D005260:Female; D036781:Fimbriae Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D010861:Fimbriae, Bacterial / Q000145:classification*; D006801:Humans; D014552:Urinary Tract Infections / Q000382:microbiology
chemical_list: D018830:Adhesins, Escherichia coli; D000900:Anti-Bacterial Agents; C058769:fimH protein, E coli; D036781:Fimbriae Proteins
keywords: FimH; UTI; flow cell; infection; urine; uropathogenic E. coli