aN. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
bState Research Center for Applied Microbiology and Biotechnology, Obolensk, Russia
KEYWORDS: Yersinia rohdei; O-specific polysaccharide; O-antigen gene cluster; lipopolysaccharide; yersiniose; bacterial polysaccharide structure; NMR simulation
International Journal of Biological Macromolecules, 2018, submitted
A branched O-polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of Yersinia rohdei H274-36/78 and found to contain D-rhamnose, D-mannose, and 3,6-dideoxy-4-C-[(S)-1-hydroxyethyl]-D-xylo-hexose called yersiniose A (Yer). Partial acid hydrolysis of the O-polysaccharide eliminated Yer residues to give a modified linear polysaccharide. Studies by sugar analysis and 1H and 13C NMR spectroscopy, including computational NMR analysis, enabled structure elucidation of a hexasaccharide repeating unit of the O-polysaccharide having two Yer residues attached as monosaccharide side chains. The O-antigen gene cluster of Y. rohdei H274-36/78 located between JUMPStart and galF genes contained putative genes for synthesis of precursors of two O-antigen constituents, GDP-D-Man and GDP-D-Rha, whereas genes responsible for synthesis of CDP-Yer were within the chromosome outside the O-antigen gene cluster. Glycosyltransferase genes and ABC 2 transporter genes were present in the O-antigen gene cluster, and hence the structure established is consistent with the polysaccharide synthesis gene content of the genome.