ISOLATION AND CHARACTERIZATION OF LIPOPOLYSACCHARIDE OF THIOCAPSA-ROSEOPERSICINA

The lipopolysaccharide from Thiocapsa roseopersicina was isolated by phenol/water, being found in the water phase. It is cleaved into a polysaccharide moiety (degraded polysaccharide) and lipid A by hydrolysis with 10% acetic acid (100°C, 3h). d‐Mannose, l‐rhamnose, 3‐amino‐3,6‐dideoxy‐d‐galactose and d‐glucose are the major constituents of the degraded polysaccharide. 2‐O‐Methyl‐l‐rhamnose, 3‐O‐methyl‐d‐mannose, d‐galactose, glucosamine and quinovosamine are minor constituents. d‐Glycero‐d‐manno‐heptose (tentatively identified) and 3‐deoxy‐d‐manno‐octulosonic acid were detected in only small amounts. Conspicuously, lipid A from T. roseopersicina contains a neutral sugar, d‐mannose, in addition to d‐glucosamine, as had been observed with lipid A from Chromatium vinosum D. Major fatty acids are β‐hydroxymyristic and lauric acids. Only trace amounts of phosphorus were found indicating this lipid A to be free of phosphate. The lipopolysaccharide of T. roseopersicina represents the O‐antigen of the strain. It reacts with antisera prepared against living or heat‐killed cells in passive hemagglutination. Copyright © 1978, Wiley Blackwell. All rights reserved