Molecular analysis of the rfb gene cluster of a group D2 Salmonella enterica strain: Evidence for its origin from an insertion sequence-mediated recombination event between group E and D1 strains

S. H. Xiang, M. Hobbs, P. R. Reeves

Research output: Contribution to journalArticle

77 Scopus citations

Abstract

The Salmonella enterica O antigen is a highly variable surface polysaccharide composed of a repeated oligosaccharide (the O unit). The O unit produced by serogroup D2 has structural features in common with those of groups D1 and E1, and hybridization studies had previously suggested that the D2 rfb gene cluster responsible for O-unit biosynthesis is indeed a hybrid of the two. In this study, the rfb gene cluster was cloned from a group D2 strain of S. enterica sv. Strasbourg. Mapping, hybridization, and DNA sequencing showed that the organization of the D2 rfb genes is similar to that of group D1, with the α-mannosyl transferase gene rfbU replaced by rfbO, the E1-specific β-mannosyl transferase gene. The E1-specific polymerase gene (rfc) has also been acquired. Interestingly, the D1-like and E1-like rfb regions are separated by an additional sequence closely related to an element (Hinc repeat [H-rpt]) associated with the Rhs loci of Escherichia coli. The H-rpt resembles an insertion sequence and possibly mediated the intraspecific recombination events which produced the group D2 rfb gene organization.

Original languageEnglish (US)
Pages (from-to)4357-4365
Number of pages9
JournalJournal of bacteriology
Volume176
Issue number14
DOIs
StatePublished - 1994

ASJC Scopus subject areas

  • Microbiology
  • Molecular Biology

Fingerprint Dive into the research topics of 'Molecular analysis of the rfb gene cluster of a group D2 Salmonella enterica strain: Evidence for its origin from an insertion sequence-mediated recombination event between group E and D1 strains'. Together they form a unique fingerprint.

  • Cite this