Structural studies of the extracellular polysaccharide produced by Butyrivibrio fibrisolvens strain H10b

摘要

The extracellular polysaccharide produced by Butyrivibrio fibrisolvents strain H10b, when grown under strictly anaerobic conditions with glucose as carbohydrate source, has been studied by chemical and spectroscopic techniques. The results demonstrate that the polysaccharide consists of hexasaccharide repeating units with the following structure: [->4)-alpha-D-Galp-(1->4)-beta-D-Glcp-(1->4)-3-O-[(S)-1-carboxyethyl]-beta-D-Glcp-(1->4)-alpha-D-Galp-(1->4)-6-(O)-[(R)-1-carboxyethyl]-alpha-D-Galp-(1] The isolated polysaccharide was found to be approx 65% acetlated at 0-2 of the 3-O-[(S)-1-carboxyethyl]-beta-D-Glcp residue. The absolute configuration of the 1-carboxyethyl groups was determined by circular dichroism.