Abstract
An acetic acid bacterium which produces a new type of extracellular soluble polysaccharide was isolated from vinegar mash. The isolated strain, NBI 1022, was tentatively identified as Acetobacter aceti subsp. xylinum. The polysaccharide, named AM-2, was composed of D-glucose, L-rhamnose, D-mannose, D-glucuronic acid, and O-acetyl in a molar ratio of approximately 4:1:1:1:1. From the results of methylation, Smith degradation, and partial acid hydrolysis of the polysaccharide and its derivatives, the polysaccharide AM-2 may have a branched structure containing a backbone chain of β-(1→4)-linked D-glucose residues and a side chain shown as L-rhamnosyl-(1→6)-β-D-glucosyl-(1→6)-D-glucosyl-(1→4)-D-glucuronosyl-(1→2)-D-mannose.
