Induction and Catabolite Repression of β-Glucosidase Synthesis in Myceliophthora thermophila D-14 (= ATCC 48104)

Abstract

β-Glucosidase activity in Myceliophthora thermophila D-14 (= ATCC 48104) was inducible and was produced in culture filtrate during growth with various inducers, of which PNPG ( p -nitrophenyl-β- d -glucoside) was the most efficient. Induction of β-glucosidase also occurred when the organism was grown in medium supplemented with different carbon sources. Carboxymethyl cellulose, cellobiose, and Solka-Floc were found effective for induction of enzyme biosynthesis. The addition of glucose to the culture medium severely repressed β-glucosidase synthesis, which could not be reversed by exogenous cyclic AMP or dibutyryl cyclic AMP.