Affiliation:
1. Department of Microbiology, University of Guelph, Ontario, Canada.
Abstract
Vibrio ordalii and Vibrio anguillarum O2 express lipopolysaccharide (LPS) O antigens containing both specific and cross-reactive epitopes. The localization of these epitopes on the O antigen is not known. We have cloned and expressed the rfb gene cluster for O-antigen synthesis from V. anguillarum O2 (rfbVaO2) in Escherichia coli. E. coli DH5 alpha containing the recombinant plasmid pAM86 expressed O antigens which reacted with polyclonal antisera to V. ordalii and to V. anguillarum O2 LPS and with monoclonal antibody (MAb) 7B4, which is specific for V. anguillarum O2 O antigens. The recombinant strains were also protected from bactericidal killing by normal fish serum. Surprisingly, the LPS expressed from the cloned rfbVaO2 genes also reacted with MAb A16, which is specific for V. ordalii O antigens. Western immunoblot analysis revealed that MAb 7B4 reacted with recombinant LPS bearing shorter O-antigen repeat units, while MAb A16 reacted with the longer O antigens. Similar results were obtained when pAM86 was transformed into E. coli CLM4, which has a deletion spanning the sbcB-rfb region, indicating that the changes in antigenic profiles of O antigens from the recombinant strains were not due to genes within the E. coli rfb cluster. These data suggest that the epitope recognized by the MAb A16 is expressed by V. anguillarum O2 strains but it is apparently not accessible to the antibody in the native O polysaccharide. Cloning of the rfbVaO2 gene cluster resulted in expression of a novel O antigen. The modification(s) which leads to the alterations in antigenic profile of these recombinant LPS remains to be determined.
Publisher
American Society for Microbiology
Subject
Infectious Diseases,Immunology,Microbiology,Parasitology
Reference24 articles.
1. A different vibriosis problem in New Brunswick salmon rearing;Airdrie D. W.;Bull. Aquacult. Assoc. Can.,1989
2. Vibrio anguillarum som arsag til ulcussygdom hos torsk (Gardus callarias, Linne);Bagge J.;Nord Veterinaermed. Bb.,1956
3. Development of monoclonal antibodies that identify Vibrio species commonly isolated from infections of humans, fish, and shellfish;Chen D.;Appl. Environ. Microbiol.,1992
4. Hadfield C. 1987. Genomic library cloning with plasmid lambda and cosmid vectors p. 61-105. In G. J. Boulnois (ed.) Gene cloning and analysis: a laboratory guide. Blackwell Scientific Publications Oxford.
5. Morphological heterogeneity among Salmonella lipopolysaccharide chemotypes in silver-stained polyacrylamide gels;Hitchcock P. J.;J. Bacteriol.,1983
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