The cellulolytic system of Talaromyces emersonii

Abstract

The thermophyllic fungus Talaromyces emersonii produces three extracellular and one intracellular enzymes exhibiting β-glucosidase (1,4-(1,3;1,4)-β-d-glucan 4-glucanohydrolase, EC 3.2.1.21) activity. Two of the extracellular forms β-glucosidase I and β-glucosidase III have been purified as has the intracellular, β-glucosidase IV. The pH and temperature, optima, stability, kinetic parameters and substrate specificity of each has been determined. We conclude that β-glucosidase I and β-glucosidase IV are true cellobiases while β-glucosidase III is an exo-β-1,4-glucose hydrolase.