title: Is biofilm formation related to the hypermutator phenotype in clinical Enterobacteriaceae isolates?
abstract: In bacteria, complex adaptive processes are involved during transition from the planktonic to the biofilm mode of growth, and mutator strains are more prone to producing biofilms. Enterobacteriaceae species were isolated from urinary tract infections (UTIs; 222 strains) and from bloodstream infections (BSIs; 213 strains). Relationship between the hypermutable phenotype and biofilm forming capacity was investigated in these clinical strains. Mutation frequencies were estimated by monitoring the capacity of each strain to generate mutations that conferred rifampicin resistance on supplemented medium. Initiation of biofilm formation was assayed by determining the ability of the cells to adhere to a 96-well polystyrene microtitre plate. UTI Enterobacteriaceae strains showed significantly higher biofilm-forming capacity: 63.1% (54.0% for E. coli strains) vs. 42.3% for BSI strains (47.7% for E. coli). Strains isolated from UTIs did not present higher mutation frequencies than those from BSIs: contrary to what has been widely described for P. aeruginosa strains, isolated from pulmonary samples in patients suffering from cystic fibrosis, no relationship was found between the hypermutator phenotype in Enterobacteriaceae and the ability to initiate a biofilm.
authors.affiliation: Department of Urology, Jahn Ferenc South-Pest Hospital, Budapest, Hungary.
authors.forename: Bela
authors.initials: B
authors.lastname: Kovacs
authors.forename: Sandrine
authors.initials: S
authors.lastname: Le Gall-David
authors.forename: Pascal
authors.initials: P
authors.lastname: Vincent
authors.forename: Hervé
authors.initials: H
authors.lastname: Le Bars
authors.forename: Sylvie
authors.initials: S
authors.lastname: Buffet-Bataillon
authors.forename: Martine
authors.initials: M
authors.lastname: Bonnaure-Mallet
authors.forename: Anne
authors.initials: A
authors.lastname: Jolivet-Gougeon
mesh_terms: D018441:Biofilms; D004755:Enterobacteriaceae / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D004756:Enterobacteriaceae Infections / Q000382:microbiology*; D006801:Humans; D009154:Mutation / Q000235:genetics; D012293:Rifampin / Q000494:pharmacology
chemical_list: D012293:Rifampin
keywords: bloodstream infection; hypermutation; mutation frequencies; urinary tract infection