Structure of the terminal reducing heptasaccharide of polysaccharide 1 isolated from the Bordetella pertussis endotoxin

Abstract

The tetrasaccharide beta-D-glucopyranosyl-(1,3)-beta-D-glucopyranuronyl-(1, 2)-L-glycero-alpha-D-manno-heptopyranosyl-(1,5)-3-deoxy-D-manno-2- octulosonic acid was isolated after treatment of polysaccharide 1 of Bordetella pertussis endotoxin with nitrous acid. Taking into account previously identified di- and trisaccharide fragments and analytical data obtained for the intact polysaccharide 1, we present the structure of a heptasaccharide that is thought to represent the region immediately adjacent to the hydrophobic (lipid A) moiety of lipopolysaccharide 1 of the B. pertussis endotoxin. This heptasaccharide represents 50 to 60% of the complete polysaccharide structure.