O-antigen variation in Salmonella spp.: rfb gene clusters of three strains.

Department of Microbiology, University of Sydney, New South Wales, Australia.
Journal of Bacteriology (Impact Factor: 2.69). 02/1988; 170(1):103-7.
Source: PubMed

ABSTRACT The O antigens of Salmonella serogroups A, B, and D differ structurally in their side-chain sugar residue. These genes encoding O-antigen biosynthesis are clustered in the rfb operon. We report here the molecular cloning and analysis of the rfb operons of Salmonella paratyphi A (serogroup A) and S. typhi (serogroup D). The regions of DNA nonhomology between the rfb operons of these serogroup A, B, and D representatives are identified, and the evolutionary derivation of serogroup A from a serogroup D progenitor is discussed.

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