AN INDUCIBLE SYSTEM FOR THE HYDROLYSIS AND TRANSPORT OF BETA-GLUCOSIDES IN YEAST. I. CHARACTERISTICS OF THE BETA-GLUCOSIDASE ACTIVITY OF INTACT AND OF LYSED CELLS.
A strain of bakers' yeast was isolated which could utilize cellobiose and other beta-D-glucosides quantitatively as carbon and energy sources for growth. Cellobiose-grown cells contained a largely cryptic enzyme active against the chromogenic substrate p-nitrophenyl-beta-D-glucoside. The patent (intact cell) activity of such cells was inhibited by azide and, competitively, by cellobiose; neither agent inhibited the beta-glucosidase activity of lysed cells or of extracts. The enzyme induced by growth in cellobiose medium had no affinity for cellobiose as either substrate or inhibitor; its substrate specificity classifies it as an aryl-beta-glucosidase. It was concluded that growth in cellobiose also induced the formation of a stereospecific and energy-dependent system whose function determined the rate at which intact cells could hydrolyze substrates of the intracellular beta-glucosidase.
D001386:Azides; D001692:Biological Transport; D050260:Carbohydrate Metabolism; D002475:Cellobiose; D044602:Cellulases; D005949:Glucose Oxidase; D005959:Glucosidases; D005960:Glucosides; D006027:Glycosides; D006868:Hydrolysis; D008660:Metabolism; D010600:Pharmacology; D012106:Research; D012440:Saccharomyces; D012441:Saccharomyces cerevisiae; D013379:Substrate Specificity; D013696:Temperature; D001617:beta-Glucosidase
D001386:Azides; D005960:Glucosides; D006027:Glycosides; D002475:Cellobiose; D005949:Glucose Oxidase; D044602:Cellulases; D005959:Glucosidases; D001617:beta-Glucosidase
AZIDES; CARBOHYDRATE METABOLISM; EXPERIMENTAL LAB STUDY; GLUCOSE OXIDASE; GLUCOSIDASE; GLYCOSIDES; METABOLISM; PHARMACOLOGY; SACCHAROMYCES; TEMPERATURE