This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Struve, C.
Right arrow Articles by Krogfelt, K. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Struve, C.
Right arrow Articles by Krogfelt, K. A.

 Previous Article  |  Next Article 

Infection and Immunity, September 2008, p. 4055-4065, Vol. 76, No. 9
0019-9567/08/$08.00+0     doi:10.1128/IAI.00494-08
Copyright © 2008, American Society for Microbiology. All Rights Reserved.

Characterization of Klebsiella pneumoniae Type 1 Fimbriae by Detection of Phase Variation during Colonization and Infection and Impact on Virulence{triangledown}

Carsten Struve,* Martin Bojer, and Karen Angeliki Krogfelt

Department of Bacteriology, Mycology and Parasitology, Statens Serum Institut, 2300 Copenhagen S, Denmark

Received 22 April 2008/ Returned for modification 27 May 2008/ Accepted 4 June 2008

Klebsiella pneumoniae is recognized as an important gram-negative opportunistic pathogen. The ability of bacteria to adhere to host structures is considered essential for the development of infections; however, few studies have examined the influence of adhesion factors on K. pneumoniae virulence. In this study, we cloned and characterized the type 1 fimbria gene cluster of a clinical K. pneumoniae isolate. Although this cluster was not identical to the Escherichia coli type 1 fimbria gene cluster, an overall high degree of structural resemblance was demonstrated. Unique to the K. pneumoniae fim gene cluster is the fimK gene, whose product contains an EAL domain, suggesting that it has a role in regulation of fimbrial expression. Like expression of type 1 fimbriae in E. coli, expression of type 1 fimbriae in K. pneumoniae was found to be phase variable, and an invertible DNA element (fim switch) was characterized. An isogenic type 1 fimbria mutant was constructed and used to evaluate the influence of type 1 fimbriae in different infection models. Type 1 fimbriae did not influence the ability of K. pneumoniae to colonize the intestine or infect the lungs, but they were determined to be a significant virulence factor in K. pneumoniae urinary tract infection. By use of a PCR-based assay, the orientation of the fim switch during colonization and infection was investigated and was found to be all "off" in the intestine and lungs but all "on" in the urinary tract. Our results suggest that during colonization and infection, there is pronounced selective pressure in different host environments for selection of either the type 1 fimbriated or nonfimbriated phenotype of K. pneumoniae.

* Corresponding author. Mailing address: Department of Bacteriology, Mycology and Parasitology, Statens Serum Institut, Artillerivej 5, 2300S Copenhagen, Denmark. Phone: 45 3268 8173. Fax: 45 3268 3147. E-mail: cas{at}ssi.dk

{triangledown} Published ahead of print on 16 June 2008.

Editor: B. A. McCormick

Infection and Immunity, September 2008, p. 4055-4065, Vol. 76, No. 9
0019-9567/08/$08.00+0     doi:10.1128/IAI.00494-08
Copyright © 2008, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Struve, C., Bojer, M., Krogfelt, K. A. (2009). Identification of a Conserved Chromosomal Region Encoding Klebsiella pneumoniae Type 1 and Type 3 Fimbriae and Assessment of the Role of Fimbriae in Pathogenicity. Infect. Immun. 77: 5016-5024 [Abstract] [Full Text]  
  • Stahlhut, S. G., Tchesnokova, V., Struve, C., Weissman, S. J., Chattopadhyay, S., Yakovenko, O., Aprikian, P., Sokurenko, E. V., Krogfelt, K. A. (2009). Comparative Structure-Function Analysis of Mannose-Specific FimH Adhesins from Klebsiella pneumoniae and Escherichia coli. J. Bacteriol. 191: 6592-6601 [Abstract] [Full Text]  
  • Tu, Y.-C., Lu, M.-C., Chiang, M.-K., Huang, S.-P., Peng, H.-L., Chang, H.-Y., Jan, M.-S., Lai, Y.-C. (2009). Genetic Requirements for Klebsiella pneumoniae-Induced Liver Abscess in an Oral Infection Model. Infect. Immun. 77: 2657-2671 [Abstract] [Full Text]  
  • Stahlhut, S. G., Chattopadhyay, S., Struve, C., Weissman, S. J., Aprikian, P., Libby, S. J., Fang, F. C., Krogfelt, K. A., Sokurenko, E. V. (2009). Population Variability of the FimH Type 1 Fimbrial Adhesin in Klebsiella pneumoniae. J. Bacteriol. 191: 1941-1950 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»