The structure of the carbohydrate backbone of the core-lipid A region of the lipopolysaccharide from Proteus mirabilis serotype O28.

The following structure of the lipid A-core region of the lipopolysaccharide (LPS) from Proteus mirabilis serotype O28 was determined using NMR, MS, and chemical analysis of the core oligosaccharide, obtained by mild acid hydrolysis of LPS, and of the products of alkaline deacylation of the LPS: carbohydrate sequence [see text] where S = beta-GalALys (amide of beta-D-galactopyranosyluronic acid with the alpha-amino group of L-lysine) or beta-GalALys4PEtN are present in the ratio of approximately 1:1. beta-GalA and Ara4N (indicated by bold italics) are present in non stoichometric amount. All sugars are present in the pyranose form and all except L-Ara4N have the D configuration.