Biochemical and proteomic characterization of a novel extracellular β-glucosidase from Trichoderma citrinoviride.

β-Glucosidases are of pivotal importance in bioconversion of carbonic biomass into fermentable and other useful metabolites, food industry, biotransformation, glyco-trimming of metabolome, etc. Trichoderma citrinoviride when grown on delignified Lantana camara produced a β-glucosidase and secreted it out in the medium. The extracellularly secreted β-glucosidase of T. citrinoviride was homogeneity purified and then characterized for its kinetic properties and proteomic characteristics. The 90 kDa enzyme was monomeric in nature, optimally active at pH 5.5 and the catalytic reaction rate was highest at 55°C. Uniquely, the enzyme was insensitive to inhibition by glucose (up to 5 mM). It also possessed catalytic ability of transglycosylation, as it could catalyze conversion of geraniol into its glucoside. MALDI-TOF assisted proteomic analysis revealed its high degree of sequence similarity with family 3 glycoside hydrolases.