THE POLYSACGHARIDES OF CRYPTOCOCCUS LAURENTII (Y1401): PART II. BIOSYNTHESIS OF THE CARBOHYDRATES FOUND IN THE ACIDIC POLYSACCHARIDE

Abstract

Cryptococcuslaurentii was grown on media which contained D-glucose-1-C14, D-glucose-6-C14, D-mannose-1-C14D-galactose-1-C14, D-xylose-1-C14, and L-arabinose-1-C14. The radioactive polysaccharides were isolated and hydrolyzed. The distribution of the radioactivity in D-mannose, D-xylose, and D-glucuronic acid isolated from the polysaccharides was determined.The results show that (A) D-mannose and D-glucuronic acids are formed from the hexoses without any appreciable breakdown of the hexose skeleton; (B) D-xylose is formed from the hexoses mainly by a process involving loss of carbon-6; (C) D-xylose and L-arabinose are both converted to D-mannose, D-xylose, and D-glucuronic acid with rearrangement of the pentose skeleton that may involve the action of transaldolase and transketolase.