Chemical studies of partially hydrolysed lipopolysaccharides from four strains of Campylobacter jejuni and two strains of Campylobacter coli

Abstract

Lipopolysaccharides (LPS) from four strains of Campylobacter jejuni and two strains of C. coli were partially hydrolysed with 1% acetic acid. Subsequent chloroform extraction led to the formation of a polysaccharide-containing aqueous layer, an interfacial material and a lipid A-containing chloroform layer. The polysaccharides contained the neutral sugars, amino sugars, 2-keto-3-deoxy-octonic acid, and part of the phosphorus present in the undegraded LPS. The lipid As were made up of glucosamine, phosphorus, ester- and amide-linked 3-hydroxytetradecanoic acid, and ester-linked n-tetradecanoic and n-hexadecanoic acid. The interfacial material was made up of lipid A and undegraded LPS. When chromatographed on Bio-GEl P-60, the degraded polysaccharides were eluted as two incompletely separated peaks (strains NCTC 11168, NCTC 11351, 11041 and 11101) or as one peak (strains NCTC 11392 and E 8035). All peaks appeared close to the total volume of the column. When the different fractions were re-chromatographed on Bio-GEl P-10, the peaks still appeared close to the total volume of the column. These findings indicate that LPS from C. jejuni and C. coli are devoid of long O-antigenic side-chains.