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. 1989 Oct;171(10):5694–5701. doi: 10.1128/jb.171.10.5694-5701.1989

Identification and sequence of rfbS and rfbE, which determine antigenic specificity of group A and group D salmonellae.

N Verma 1, P Reeves 1
PMCID: PMC210416  PMID: 2793833

Abstract

Salmonella group A, group B, and group D strains have paratose, abequose, and tyvelose, respectively, as the immunodominant sugar in their O antigens, which are otherwise identical; only the final steps differ in the biosynthetic pathways of these sugars. The gene rfbJ from a group B strain, encoding abequose synthase, the final and only unique step in the biosynthesis of CDP-abequose, has been cloned and sequenced (P. Wyk and P. Reeves, J. Bacteriol. 171:5687-5693, 1989). In this study, we locate and sequence rfbS and rfbE from serovars typhi and paratyphi, representative of groups A and D. Gene rfbS is present in both groups and encodes paratose synthase, which carries out a step parallel to that of abequose synthase, but the product is CDP-paratose. The DNA and inferred amino acid sequences are compared with those of rfbJ. We conclude that the genes are homologous, but the divergence is extremely ancient. Gene rfbE encodes CDP-tyvelose epimerase, which converts CDP-paratose to CDP-tyvelose in group D strains; the gene is active in group D strains, and we find it to be present in a mutant form in group A strains. These two genes encode the steps unique to groups A and D and, like rfbJ of group B, are of low G+C content, suggesting transfer from outside of salmonellae. The evolutionary origin of these genes is discussed.

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Selected References

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  1. Brahmbhatt H. N., Wyk P., Quigley N. B., Reeves P. R. Complete physical map of the rfb gene cluster encoding biosynthetic enzymes for the O antigen of Salmonella typhimurium LT2. J Bacteriol. 1988 Jan;170(1):98–102. doi: 10.1128/jb.170.1.98-102.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Frazer A. C., Curtiss R., 3rd Production, properties and utility of bacterial minicells. Curr Top Microbiol Immunol. 1975;69:1–84. doi: 10.1007/978-3-642-50112-8_1. [DOI] [PubMed] [Google Scholar]
  3. Germanier R., Füer E. Isolation and characterization of Gal E mutant Ty 21a of Salmonella typhi: a candidate strain for a live, oral typhoid vaccine. J Infect Dis. 1975 May;131(5):553–558. doi: 10.1093/infdis/131.5.553. [DOI] [PubMed] [Google Scholar]
  4. Kanehisa M. I. Los Alamos sequence analysis package for nucleic acids and proteins. Nucleic Acids Res. 1982 Jan 11;10(1):183–196. doi: 10.1093/nar/10.1.183. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Lemaire H. G., Müller-Hill B. Nucleotide sequences of the gal E gene and the gal T gene of E. coli. Nucleic Acids Res. 1986 Oct 10;14(19):7705–7711. doi: 10.1093/nar/14.19.7705. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Matsuhashi S. Enzymatic synthesis of cytidine diphosphate 3,6-dideoxyhexoses. II. Reversible 2-epimerization of cytidine diphosphate paratose. J Biol Chem. 1966 Sep 25;241(18):4275–4282. [PubMed] [Google Scholar]
  7. Nikaido H., Levinthal M., Nikaido K., Nakane K. Extended deletions in the histidine-rough-B region of the Salmonella chromosome. Proc Natl Acad Sci U S A. 1967 Jun;57(6):1825–1832. doi: 10.1073/pnas.57.6.1825. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Ornellas E. P., Stocker B. A. Relation of lipopolysaccharide character to P1 sensitivity in Salmonella typhimurium. Virology. 1974 Aug;60(2):491–502. doi: 10.1016/0042-6822(74)90343-2. [DOI] [PubMed] [Google Scholar]
  9. Poustka A., Rackwitz H. R., Frischauf A. M., Hohn B., Lehrach H. Selective isolation of cosmid clones by homologous recombination in Escherichia coli. Proc Natl Acad Sci U S A. 1984 Jul;81(13):4129–4133. doi: 10.1073/pnas.81.13.4129. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Sasaki T., Uchida T. Mutants of group D1 Salmonella carrying the somatic antigen of group A organisms: evidence for the lack of cytidine diphosphate paratose-2-epimerase activity. J Bacteriol. 1974 Jan;117(1):13–18. doi: 10.1128/jb.117.1.13-18.1974. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Verma N. K., Quigley N. B., Reeves P. R. O-antigen variation in Salmonella spp.: rfb gene clusters of three strains. J Bacteriol. 1988 Jan;170(1):103–107. doi: 10.1128/jb.170.1.103-107.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Wyk P., Reeves P. Identification and sequence of the gene for abequose synthase, which confers antigenic specificity on group B salmonellae: homology with galactose epimerase. J Bacteriol. 1989 Oct;171(10):5687–5693. doi: 10.1128/jb.171.10.5687-5693.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]

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