STRUCTURAL INVESTIGATION OF THE CAPSULAR POLYSACCHARIDE OF ESCHERICHIA-COLI O101-K103-H- USING BACTERIOPHAGE DEGRADATION AND NMR-SPECTROSCOPY

NMR spectroscopy was performed on the depyruvated capsular antigen of E. coli K103 and on the oligosaccharide obtained by depolymerisation o f the native polysaccharide with a viral-borne endoglycanase. This cap sular polysaccharide is the only one to be co-expressed with O group 1 01 and joins a small group of unusual capsular polysaccharides which p ossess pyruvic acid as the only acidic function. The primary structure was shown to be composed of the repeating unit:[GRAPHICS]