Structural studies on the hexose region of the Enterobacteriaceae type R3 core polysaccharide

The structure of the hexose region of the Enterobacteriaceae type R3 core polysaccharide, which is the common core in Shigella flexneri and some Escherichia coli lipopolysaccharides (LPS), has been investigated. The principal method used in these studies involved methylation analysis of the original and modified materials. The polysaccharide was modified by N-deacetylation-deamination and by Smith degradation. As a result of these studies, the following structure is proposed: alpha-D-Glcp-(1 leads to 2)-alpha-D-Glcp-(1 leads to 2)-[alpha-D-GlcNAcp-(1 leads to 3)]-alpha-D-Galp-(1 leads to 3)-alpha-D-Glcp-(1 leads to.