Purification and Characterization of two Extracellular β‐Glucosidases from Trichoderma viride ITCC 1433

Abstract

SumiiiaryT. viride ITCC 1433 synthesizes a two component system for the hydrolysis of cellobiose and cellooligodextrins. 80% of the total activity are solubilized during growth. The large protein (A), mol. weight 98000 d, is glycosylated and slightly acidic (pH = 6.1). The smaller protein (B), mol. weight 70000 d, is unglycosylated and neutral (pH = 7.2). Both proteins form a two-step system where P-glucosidase A is active a t low substrate concentrations (KSlf = 2.3 x M cellobiose) while P-glucosidase B covers the range of 10-fold higher cellobiose concentrations (KJf = 1.8x 31). The enzymes are fiiirly stable with a residual activity of 70% a t 50°C after 24 h.

Affinity chromatography of 1,4‐β‐glucosidase from trichoderma reesei QM 9414

“…This enzyme of molecular weight around 76 kD was moderately active on CM-cellulose, crystaline cellulose and xylan. WILHELM and SAHM[32] obtained after chromatography and gel filtration two protein fractions…”