Structure of the lipopolysaccharide O-chain of Yersinia enterocolitica serotype O:5,27

Abstract

The cellular lipopolysaccharide produced by Yersinia enterocolitica serotype O:5,27 was of the S-type and composed of an antigenic O-chain polysaccharide linked through a core oligosaccharide region, which in turn was linked through 3-deoxy-D-manno-octulonosyl units to a lipid A moiety. The O-chain polysaccharide was composed of equal molar amounts of L-rhamnose and D-xylulose. By partial hydrolysis, periodate oxidation, methylation, specific optical rotation, and 13C and 1H nuclear magnetic resonance studies, the structure of the O-chain was established as being a linear backbone of alternating 1,3-linked α-L-rhamnopyranosyl and β-L-rhamnopyranosyl units, to which 2,2-linked β-D-threo-pent-2-ulofuranoside (D-xylulofuranoside) units were present on every L-rhamnopyranosyl residue, as shown below.[Formula: see text]