This Article Full Text Full Text (PDF) 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.

 Previous Article  |  Next Article 

Journal of Bacteriology, September 2005, p. 6213-6222, Vol. 187, No. 17
0021-9193/05/$08.00+0     doi:10.1128/JB.187.17.6213-6222.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.

The N-Terminal Domain of Enterococcal Surface Protein, Esp, Is Sufficient for Esp-Mediated Biofilm Enhancement in Enterococcus faecalis

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

Received 14 March 2005/ Accepted 2 June 2005

Enterococci have emerged as one of the leading causes of nosocomial bloodstream, surgical site, and urinary tract infections. More recently, enterococci have been associated with biofilms, which are bacterial communities attached to a surface and encased in an extracellular polymeric matrix. The enterococcal cell surface-associated protein, Esp, enhances biofilm formation by Enterococcus faecalis in a glucose-dependent manner. Mature Esp consists of a nonrepeat N-terminal domain and a central region made up of two types of tandem repeats followed by a C-terminal membrane-spanning and anchor domain. This study was undertaken to localize the specific domain(s) of Esp that plays a role in Esp-mediated biofilm enhancement. To achieve this objective, we constructed in-frame deletion mutants expressing truncated forms of Esp in an isogenic background. By comparing strains expressing the mutant forms of Esp to those expressing wild-type Esp, we found that the strain expressing Esp lacking the N-terminal domain formed biofilms that were quantitatively less in biovolume than the strain expressing wild-type Esp. Furthermore, an E. faecalis strain expressing only the N-terminal domain of Esp fused to a heterologous protein anchor formed biofilms that were quantitatively similar to those formed by a strain expressing full-length Esp. This suggested that the minimal region contributing to Esp-mediated biofilm enhancement in E. faecalis was confined to the nonrepeat N-terminal domain. Expression of full-length E. faecalis Esp in heterologous host systems of esp-deficient Lactococcus lactis and Enterococcus faecium did not enhance biofilm formation as was observed for E. faecalis. These results suggest that Esp may require interaction with an additional E. faecalis-specific factor(s) to result in biofilm enhancement.

This article has been cited by other articles:

• 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]  
• 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]