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The Enterococcus faecalis fsr two-component system controls biofilm development through production of gelatinase.

Lynn E Hancock·Marta Perego
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Abstract

Bacterial growth as a biofilm on solid surfaces is strongly associated with the development of human infections. Biofilms on native heart valves (infective endocarditis) is a life-threatening disease as a consequence of bacterial resistance to antimicrobials in such a state. Enterococci have emerged as a cause of endocarditis and nosocomial infections despite being normal commensals of the gastrointestinal and female genital tracts. We examined the role of two-component signal transduction systems in biofilm formation by the Enterococcus faecalis V583 clinical isolate and identified the fsr regulatory locus as the sole two-component system affecting this unique mode of bacterial growth. Insertion mutations in the fsr operon affected biofilm formation on two distinct abiotic surfaces. Inactivation of the fsr-controlled gene gelE encoding the zinc-metalloprotease gelatinase was found to prevent biofilm formation, suggesting that this enzyme may present a unique target for therapeutic intervention in enterococcal endocarditis.

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Adaptation, PhysiologicalBacterial ProteinsBiofilmsEnterococcus faecalisGelatinasesGene Expression Regulation, BacterialGene OrderGenes, BacterialGenes, RegulatorHistidine KinaseMutagenesis, InsertionalMutationOperonProtein KinasesSerine EndopeptidasesSignal TransductionJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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Lynn E Hancock, Marta Perego. 2004. The Enterococcus faecalis fsr two-component system controls biofilm development through production of gelatinase.. https://doi.org/10.1128/jb.186.17.5629-5639.2004

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