Determination of specificities of rabbit antisera against the O-antigenic polysaccharide from Escherichia coli O126

Abstract Rabbit polyclonal antibodies against the lipopolysaccharide of Escherichia coli O126 were serologically characterized by ELISA. The antibody specificities were determined by studying the inhibitory effects of the methyl glycosides of both anomeric configurations of the constituent monosaccharides and the oligosaccharides derived from the O-antigenic polysaccharides of E. coli O126. It was found that, amongst the monosaccharides, β- d -N-acetyl glucosamine was the most effective inhibitory sugar in the O126 polysaccharide and the major specificity of the polyclonal antibodies was found to be directed against the trisaccharide having the structure α- D -Gal p (1 → 3)-β- D -Glc pNAc(1→2)- D -Man p.