Structure of the O-polysaccharide and serological cross-reactivity of the lipopolysaccharide of Providencia alcalifaciens O32 containing N-acetylisomuramic acid

摘要

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, H-1 and C-13 NMR spectroscopy, including two-dimensional H-1,H-1 COSY, TOCSY, ROESY, H-detected H-1, C 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: [GRAPHICS] 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. (c) 2006 Elsevier Ltd. All rights reserved.