Composition of Lipopolysaccharides from Myxococcus fulvus and Other Fruiting and Non-Fruiting Myxobacteria

Abstract

From vegetative cells of Myxococcus fulvus the lipopolysaccharide was isolated by the phenolwater procedure and its composition studied. Mannose, d-galactose, d-glucose, rhamnose, glucos-amine and galactosamine were found to be the main sugar constituents. Smaller amounts of ribose, xylose, arabinose, 3-O-methyl-d-xylose and 2-keto-3-deoxyoetonate were also found. Heptose was absent. Among the fatty acids iso-branched fatty acids were predominant, i.e. 13-methyl-tetradecanoic acid, 3-hydroxy-13-methyltetradecanoic acid, and 3-hydroxy-15-methyl-hexadecanoic acid. In addition non-branched fatty acids were present in small amounts, like dode-canoic, tetradecanoic, hexadecanoic and octadecanoic acid as well as 3-hydroxy-tetradecanoic and 3-hydroxy-hexadecanoic acid. The 2,3- and 3,4-unsaturated fatty acids detected in hydroly-sates were shown to be artifacts formed from 3-hydroxy fatty acids during hydrolysis. By gentle acidic treatment of the lipopolysaccharide lipid A was obtained containing glucosamine, fatty acids and phosphate as the main constituents. Ester-bound and amide-bound fatty acids were differentiated. Similar sugar and fatty acid compositions were found in the lipopolysaccharides of 5 fruiting and non-fruiting strains of myxobacteria. However, heptose which was absent in the other strains occurred in the lipopolysaccharide of Flexibacter Sp Fx 1/2.