This Article Full Text Full Text (PDF) Supplemental material 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 HighWire Citing Articles via Google Scholar Google Scholar Articles by Tendolkar, P. M. Articles by Shankar, N. Search for Related Content PubMed PubMed Citation Articles by Tendolkar, P. M. Articles by Shankar, N.

Putative Surface Proteins Encoded within a Novel Transferable Locus Confer a High-Biofilm Phenotype to Enterococcus faecalis

Preeti M. Tendolkar, Arto S. Baghdayan, and Nathan Shankar^*

Department of Pharmaceutical Sciences, University of Oklahoma Health Sciences Center, P.O. Box 26901, Oklahoma City, Oklahoma 73190

Received 26 July 2005/ Accepted 4 January 2006

Enterococci are opportunistic pathogens and among the leading causes of nosocomial infections. Enterococcus faecalis, the dominant species among infection-derived isolates, has recently been recognized as capable of forming biofilms on abiotic surfaces in vitro as well as on indwelling medical devices. A few bacterial factors known to contribute to biofilm formation in E. faecalis have been characterized. To identify additional factors which may be important to this process, we utilized a Tn917-based insertional mutagenesis strategy to generate a mutant bank in a high-biofilm-forming E. faecalis strain, E99. The resulting mutant bank was screened for mutants exhibiting a significantly reduced ability to form biofilms. One mutant, P101D12, which showed greater than 70% reduction in its ability to form biofilms compared to the wild-type parent, was further characterized. The single Tn917 insertion in P101D12 was mapped to a gene, bee-2, encoding a probable cell wall-anchored protein. Sequence information for the region flanking bee-2 revealed that this gene was a member of a locus (termed the bee locus for biofilm enhancer in enterococcus) comprised of five genes encoding three putative cell wall-anchored proteins and two probable sortases. Contour-clamped homogeneous electric field gel and Southern hybridization analyses suggested that the bee locus is likely harbored on a large conjugative plasmid. Filter mating assays using wild-type E99 or mutant P101D12 as a donor confirmed that the bee locus could transfer conjugally at high frequency to recipient E. faecalis strains. This represents the first instance of the identification of a mobile genetic element conferring biofilm-forming property in E. faecalis.

These authors contributed equally to this work.

Supplemental material for this article may be found at http://jb.asm.org/.

This article has been cited by other articles:

• Kristich, C. J., Nguyen, V. T., Le, T., Barnes, A. M. T., Grindle, S., Dunny, G. M. (2008). Development and Use of an Efficient System for Random mariner Transposon Mutagenesis To Identify Novel Genetic Determinants of Biofilm Formation in the Core Enterococcus faecalis Genome. Appl. Environ. Microbiol. 74: 3377-3386 [Abstract] [Full Text]  
• Mohamed, J. A., Huang, D. B. (2007). Biofilm formation by enterococci. J Med Microbiol 56: 1581-1588 [Abstract] [Full Text]  
• Heikens, E., Bonten, M. J. M., Willems, R. J. L. (2007). Enterococcal Surface Protein Esp Is Important for Biofilm Formation of Enterococcus faecium E1162. J. Bacteriol. 189: 8233-8240 [Abstract] [Full Text]  
• Hendrickx, A. P. A., van Wamel, W. J. B., Posthuma, G., Bonten, M. J. M., Willems, R. J. L. (2007). Five Genes Encoding Surface-Exposed LPXTG Proteins Are Enriched in Hospital-Adapted Enterococcus faecium Clonal Complex 17 Isolates. J. Bacteriol. 189: 8321-8332 [Abstract] [Full Text]  
• Kemp, K. D., Singh, K. V., Nallapareddy, S. R., Murray, B. E. (2007). Relative Contributions of Enterococcus faecalis OG1RF Sortase-Encoding Genes, srtA and bps (srtC), to Biofilm Formation and a Murine Model of Urinary Tract Infection. Infect. Immun. 75: 5399-5404 [Abstract] [Full Text]  
• Bentley, M. L., Gaweska, H., Kielec, J. M., McCafferty, D. G. (2007). Engineering the Substrate Specificity of Staphylococcus aureus Sortase A: THE beta6/beta7 LOOP FROM SrtB CONFERS NPQTN RECOGNITION TO SrtA. J. Biol. Chem. 282: 6571-6581 [Abstract] [Full Text]  
• Van Wamel, W. J. B., Hendrickx, A. P. A., Bonten, M. J. M., Top, J., Posthuma, G., Willems, R. J. L. (2007). Growth Condition-Dependent Esp Expression by Enterococcus faecium Affects Initial Adherence and Biofilm Formation. Infect. Immun. 75: 924-931 [Abstract] [Full Text]  
• Tsigrelis, C., Singh, K. V., Coutinho, T. D., Murray, B. E., Baddour, L. M. (2007). Vancomycin-Resistant Enterococcus faecalis Endocarditis: Linezolid Failure and Strain Characterization of Virulence Factors. J. Clin. Microbiol. 45: 631-635 [Abstract] [Full Text]