title: Control of beta-glucosidase synthesis in Mucor racemosus.
abstract: The beta-glucosidase of Mucor racemosus was shown to be synthesized when the organism was grown in the presence of such diverse carbon sources as glycerol, lactate, xylose, ribose, alpha-methylglucoside, alpha-phenylglucoside, maltose, and cellobiose. Enzyme synthesis was strongly repressed in the presence of hexoses. In addition, exogenous cyclic adenosine 3',5'-monophosphate (cAMP) resulted in enzyme repression. When cAMP was added exogenously after enzyme activity had accumulated, a reversible enzyme inactivation occurred. Growth on disaccharides (maltose or cellobiose) was severely retarded in the presence of cAMP, whereas that on glucose remained unaffected. The results indicate a probable role for cAMP in control of glucosidase synthesis in Mucor.
mesh_terms: D002244:Carbon / Q000378:metabolism; D000242:Cyclic AMP / Q000032:analysis / Q000494:pharmacology; D003513:Cycloheximide / Q000494:pharmacology; D003609:Dactinomycin / Q000494:pharmacology; D005696:Galactosidases / Q000096:biosynthesis*; D005947:Glucose / Q000494:pharmacology; D009089:Mucor / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development; D001616:beta-Galactosidase / Q000037:antagonists & inhibitors / Q000096:biosynthesis*
chemical_list: D003609:Dactinomycin; D002244:Carbon; D003513:Cycloheximide; D000242:Cyclic AMP; D005696:Galactosidases; D001616:beta-Galactosidase; D005947:Glucose