Structure of the Acetobacter methanolicus MB 129 capsular polysaccharide, and of oligosaccharides resulting from degradation by bacteriophage Acm7

Abstract

The capsular polysaccharide of Acetobacter methanolicus MB 129 consists of D-Glc, D-Gal, L-Rha, and L-glyceric acid in the molar ratios 1:1:1:0.3. Periodate oxidation, methylation analysis, solvolysis with HF, and detailed 1H and 13C NMR analysis resulted in the structure of the repeating unit shown below. [formula: see text] Bacteriophage Acm7-associated end-alpha-L-rhamnopyranoside hydrolase depolymerizes the CPS even in the presence of the O-acyl group, to give the respective hexa-, nona-, and dodeca-saccharides.