Isolation and structure of an extracellular polysaccharide from streptomyces sp. FERM-P1185

A streptomycete strain (FERM-P1185), isolated from soil, secreted a slime on glucose-asparagine agar, and produced viscous growth in liquid media containing peptone as nitrogen source. A purified polysaccharide isolated from the culture broth was composed of glucose and mannose units (molar ratio 1-87:1). Periodate oxidation, Smith degradation, methylation analysis, infrared and 13c nuclear magnetic resonance spectra indicated that this mannoglucan had a linear structure consisting of alpha-1,3- and alpha-1,4-linked glucopyranose and mannopyranose units.