POLYHYDRIC ALCOHOL PRODUCTION BY OSMOPHILIC YEASTS: STUDIES WITH C14-LABELED GLUCOSE

Abstract

D-Glucose was dis-similated aerobically by a strain of osmophilic yeast producing glycerol, D-arabitol, ethanol, carbon dioxide, and a small amount of succinic acid. Glucose-1-Cl4 gave glycerol labeled in the terminal carbons, D-arabitol labeled in carbon-1 and carbon-5, methyl labeled ethanol, and succinic acid with 30% of the labeling in the carboxyl carbons and 70% in the methylene carbons. Glucose-2-C14 gave glycerol labeled in carbon-2, D-arabitol labeled in carbon-1, carbon-2, and carbon-4, carbinol labeled ethanoly and succinic acid having 70% of the labeling in the carboxyl carbons and 39% in the methylene carbons. Labeled carbon dioxide was produced from both carbon-1 and carbon-2 labeled glucose but the specific activity of carbon dioxide from glucose-1-C14 was higher than that from glucose-2-C14. The distribution of radioactive carbon in the products is explained by assuming that glucose is dissimilated via a combination of the Embden-Meyerhof and the phosphogluconate oxidation pathways, with transketolase-catalyzed reactions playing an important part in D-arabitol formation.