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 Hanna, A. Articles by Razatos, A. Search for Related Content PubMed PubMed Citation Articles by Hanna, A. Articles by Razatos, A. Agricola Articles by Hanna, A. Articles by Razatos, A.

Role of Capsular Colanic Acid in Adhesion of Uropathogenic Escherichia coli

Andrea Hanna,^1, Michael Berg,^2,3 Valerie Stout,^2,3 and Anneta Razatos^1,3*

Department of Chemical and Materials Engineering,¹ Department of Microbiology,² The Molecular and Cellular Biology Program, Arizona State University, Tempe, Arizona³

Received 16 January 2003/ Accepted 6 May 2003

Urinary tract infections are the most common urologic disease in the United States and one of the most common bacterial infections of any organ system. Biofilms persist in the urinary tract and on catheter surfaces because biofilm microorganisms are resistant to host defense mechanisms and antibiotic therapy. The first step in the establishment of biofilm infections is bacterial adhesion; preventing bacterial adhesion represents a promising method of controlling biofilms. Evidence suggests that capsular polysaccharides play a role in adhesion and pathogenicity. This study focuses on the role of physiochemical and specific binding interactions during adhesion of colanic acid exopolysaccharide mutant strains. Bacterial adhesion was evaluated for isogenic uropathogenic Escherichia coli strains that differed in colanic acid expression. The atomic force microscope (AFM) was used to directly measure the reversible physiochemical and specific binding interactions between bacterial strains and various substrates as bacteria initially approach the interface. AFM results indicate that electrostatic interactions were not solely responsible for the repulsive forces between the colanic acid mutant strains and hydrophilic substrates. Moreover, hydrophobic interactions were not found to play a significant role in adhesion of the colanic acid mutant strains. Adhesion was also evaluated by parallel-plate flow cell studies in comparison to AFM force measurements to demonstrate that prolonged incubation times alter bacterial adhesion. Results from this study demonstrate that the capsular polysaccharide colanic acid does not enhance bacterial adhesion but rather blocks the establishment of specific binding as well as time-dependent interactions between uropathogenic E. coli and inert substrates.

Present address: Intel Corporation, Santa Clara, CA 95052.

This article has been cited by other articles:

• Linares, J. F., Gustafsson, I., Baquero, F., Martinez, J. L. (2006). Antibiotics as intermicrobial signaling agents instead of weapons. Proc. Natl. Acad. Sci. USA 103: 19484-19489 [Abstract] [Full Text]  
• Beloin, C., Michaelis, K., Lindner, K., Landini, P., Hacker, J., Ghigo, J.-M., Dobrindt, U. (2006). The Transcriptional Antiterminator RfaH Represses Biofilm Formation in Escherichia coli. J. Bacteriol. 188: 1316-1331 [Abstract] [Full Text]  
• Reid, A. N., Whitfield, C. (2005). Functional Analysis of Conserved Gene Products Involved in Assembly of Escherichia coli Capsules and Exopolysaccharides: Evidence for Molecular Recognition between Wza and Wzc for Colanic Acid Biosynthesis. J. Bacteriol. 187: 5470-5481 [Abstract] [Full Text]  
• Li, G., Laturnus, C., Ewers, C., Wieler, L. H. (2005). Identification of Genes Required for Avian Escherichia coli Septicemia by Signature-Tagged Mutagenesis. Infect. Immun. 73: 2818-2827 [Abstract] [Full Text]  
• Chain, P. S. G., Carniel, E., Larimer, F. W., Lamerdin, J., Stoutland, P. O., Regala, W. M., Georgescu, A. M., Vergez, L. M., Land, M. L., Motin, V. L., Brubaker, R. R., Fowler, J., Hinnebusch, J., Marceau, M., Medigue, C., Simonet, M., Chenal-Francisque, V., Souza, B., Dacheux, D., Elliott, J. M., Derbise, A., Hauser, L. J., Garcia, E. (2004). Insights into the evolution of Yersinia pestis through whole-genome comparison with Yersinia pseudotuberculosis. Proc. Natl. Acad. Sci. USA 101: 13826-13831 [Abstract] [Full Text]  
• Newman, K. L., Almeida, R. P. P., Purcell, A. H., Lindow, S. E. (2004). Cell-cell signaling controls Xylella fastidiosa interactions with both insects and plants. Proc. Natl. Acad. Sci. USA 101: 1737-1742 [Abstract] [Full Text]