Structural and antigenic heterogeneity of lipopolysaccharides of Campylobacter jejuni and Campylobacter coli.

The techniques of sodium dodecyl sulfate-polyacrylamide gel electrophoresis, silver staining, and immunoblotting were used to analyze the lipopolysaccharide (LPS) structure of 20 strains of Campylobacter jejuni and 4 strains of Campylobacter coli belonging to more than 22 thermostable serotypes. The LPSs of all strains examined were shown to be of a low-molecular-weight type, and these low-molecular-weight LPSs conferred heat-stable serospecificity. High-molecular-weight banding observed with both in vivo LPS in proteinase K digests of whole cell lysates and purified LPS was shown to be due to the ready ability of Campylobacter lipopolysaccharide to form aggregates rather than to the presence of O polysaccharide chains. Purified LPSs from two strains of C. jejuni were also subjected to gross chemical analysis. The high-lipid A to low-neutral sugar ratio of both LPSs was typical of LPSs lacking O polysaccharide chains.