Structural studies of the enterotoxigenic Escherichia coli (ETEC) O153 O-antigenic polysaccharide

The O-specific side-chain of the lipopolysaccharide from Escherichia coli O153 has been investigated using methylation analysis, Smith degradation, partial hydrolysis, FABMS, and NMR spectroscopy as the principal methods. It is concluded that the polysaccharide is composed of pentasaccharide repeating-units having the following structure.