IAI FigSearch
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
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 Arora, S. K.
Right arrow Articles by Ramphal, R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Arora, S. K.
Right arrow Articles by Ramphal, R.

 Previous Article  |  Next Article 

Infection and Immunity, March 2000, p. 1474-1479, Vol. 68, No. 3
0019-9567/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.

Identification of Two Distinct Types of Flagellar Cap Proteins, FliD, in Pseudomonas aeruginosa

Shiwani K. Arora,1 Nandini Dasgupta,1 Stephen Lory,2 and Reuben Ramphal1,*

Department of Medicine/Infectious Diseases, University of Florida, Gainesville, Florida 32610,1 and Department of Microbiology, University of Washington, Seattle, Washington 981452

Received  Received 15 October 1999/Returned for modification 17 November 1999/Accepted 7 December 1999

Binding of Pseudomonas aeruginosa strain PAK to mucin has been shown to be mediated by the flagellar cap protein, product of the fliD gene. Since the flagellar cap is very likely an exposed structure, the FliD polypeptide should be recognized by the host immune system, analogous to the recognition of dominant epitopes located in the exposed parts of the flagellin polypeptide within the assembled flagellum. In P. aeruginosa, a number of distinct flagellin variants are made, and these variable sequences presumably allow the newly infected P. aeruginosa to escape recognition by the antibody induced during a previous infection. Since similar mechanisms may direct the selection of FliD variants, we examined the extent of sequence heterogeneity among various FliD sequences among a selected group of P. aeruginosa. The results of PCR and nucleotide sequencing of the fliD region of eight different P. aeruginosa strains (laboratory strains PAK, PAO1, and PA103; clinical strains 1244, CS2, and CS32; cystic fibrosis strains CS29 and MDR) suggested that there were two distinct types of FliD in P. aeruginosa, which we named A type and B type. The results of Western blotting using the polyclonal antibodies raised against the purified FliD of A type (PAK) or B type (PAO1) further confirmed the existence of two distinct antigenic types of FliD proteins, with no cross-reactivity between the two serotypes. Further Western immunoblot analysis of the same strains using polyclonal FliC antibody showed that the strains with A-type FliD possessed a-type FliC and those with B-type FliD had b-type FliC. Similar Western blot analyses of 50 more P. aeruginosa strains obtained from varied sources revealed that all strains contained either A-type or B-type FliD, suggesting the existence of only two types of FliD in P. aeruginosa and indicating that fliC and fliD were coinherited. This limited diversity of FliC and FliD serotypes seems to be a unique feature of flagellar proteins. A chromosomal mutant having an insertion in the fliD gene of P. aeruginosa PAO1 was constructed. The motility defect of this mutant and a previously constructed PAK fliD mutant was better complemented with the fliD gene of the homologous types.

* Corresponding author. Mailing address: Department of Medicine/Infectious Diseases, P.O. Box 100277, JHMHC, University of Florida, Gainesville, FL 32610. Phone: (352) 392-2932. Fax: (352) 392-6481. E-mail: RAMPHR{at}medmac.ufl.edu.

Infection and Immunity, March 2000, p. 1474-1479, Vol. 68, No. 3
0019-9567/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
J. Bacteriol. J. Virol. Eukaryot. Cell
Microbiol. Mol. Biol. Rev. Clin. Vaccine Immunol. All ASM Journals

Copyright © 2000 by the American Society for Microbiology. All rights reserved.