aN. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
bDepartment of Immunobiology of Bacteria, Institute of Microbiology and Immunology, University of Lodz, Poland
KEYWORDS: Providencia alcalifaciens, O-antigen, lipopolysaccharide, polysaccharide structure, isomuramic acid, C-13-NMR data, Proteus, classification
Carbohydrate Research, 2007, v. 342(2), pp. 268-273
The O-polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of Providencia alcalifaciens O32 and studied by sugar and methylation analyses, solvolysis with triflic acid, 1H and 13C NMR spectroscopy, including two-dimensional 1H,1H COSY, TOCSY, ROESY, H-detected 1H,13C HSQC and HMBC experiments. It was found that the polysaccharide has a branched tetrasaccharide repeating unit containing 2-acetamido-3-O+[(S)-1-carboxyethyl]-2-deoxy-D-glucose (D-Glc-NAc3Slac, N-acetylisomuramic acid) with the following structure:
bDGlcp S-Lac |4 |3 ->3)aLFucpNAc(1->3)aDGlcpNAc(1->6)aDGlcpNAc(1->
Serological studies with O-antisera showed antigenic relationships between P. alcalifaciens O32 and O29 as well as several other Providencia and Proteus strains sharing putative epitopes on the O-polysaccharides.