This Article Full Text Full Text (PDF) Other Versions of this Article: JB.01205-07v1 189/22/8233    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Heikens, E. Articles by Willems, R. J. L. Search for Related Content PubMed PubMed Citation Articles by Heikens, E. Articles by Willems, R. J. L.

Enterococcal Surface Protein Esp Is Important for Biofilm Formation of Enterococcus faecium E1162

Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands

Received 27 July 2007/ Accepted 31 August 2007

Enterococci have emerged as important nosocomial pathogens with resistance to multiple antibiotics. Adhesion to abiotic materials and biofilm formation on medical devices are considered important virulence properties. A single clonal lineage of Enterococcus faecium, complex 17 (CC17), appears to be a successful nosocomial pathogen, and most CC17 isolates harbor the enterococcal surface protein gene, esp. In this study, we constructed an esp insertion-deletion mutant in a clinical E. faecium CC17 isolate. In addition, initial adherence and biofilm assays were performed. Compared to the wild-type strain, the esp insertion-deletion mutant no longer produced Esp on the cell surface and had significantly lower initial adherence to polystyrene and significantly less biofilm formation, resulting in levels of biofilm comparable to those of an esp-negative isolate. Capacities for initial adherence and biofilm formation were restored in the insertion-deletion mutant by in trans complementation with esp. These results identify Esp as the first documented determinant in E. faecium CC17 with an important role in biofilm formation, which is an essential factor in infection pathogenesis.

Published ahead of print on 7 September 2007.