COMPOSITIONAL CONSISTENCY OF A HETEROPOLYSACCHARIDE-7 PRODUCED BY BEIJERINCKIA-INDICA

The component sugars of heteropolysaccharide-7 (PS-7) produced by Beij erinckia indica were rhamnose and glucose (1.0:4.8, mol:mol) by gas ch romatographic analysis. Galacturonic acid, previously reported as a re peat unit of PS-7, was not found in purified PS-7. The yield of PS-7 v aried with physiological conditions, such as concentration of carbon s ource and initial pH of medium, but the molar ratio of rhamnose to glu cose stayed within 1.0 to 4.6-5.1. a. indica utilized glucose and some glucose analogs as carbon sources and produced exopolymers, although there was no direct incorporation of these sugars into PS-7. The molar ratio of rhamnose to glucose in each polymer synthesized from glucose -related sugars showed no significant variation (1.0 to 4.5-4.7)