In order to obtain the fundamental informations on cellulase of Trichoderma viride QM 9414 for its production and utilization, some physico-chemical properties of the enzyme were reviewed.
When T. viride QM 9414 was cultured on wheat bran medium, filter paper-disintegrating and carboxymethyl cellulose(CMC)-saccharifying activity were incresed with the cell growth, and thereafter CMC-saccharifying activity was kept on almost the same leved while filter-paper disintegrating activity was decreased sharply. And β-glucosidase was formed maximally on the late stationary phase of growth.
The crude cellulase of cell-free extracts was purified by (NH_4)_2SO, fractionation, Sephadex-G 200 column chromatography and DEAE Sephadex A-50 column chromatography.
Filter paper-disintegrating, CMC-saccharifying and β-glucosidase activity were purified 10-fold, 47-fold and 38-fold, respectively. The crude enzyme was proved to be a complex of three different enzyme proteins which were showing filter paper-disintegrating, CMC-saccharifying and β-glucosidase activity.
The optimal pH of the three enzyme components was alike pH 4.0, and the optimal temperature for CMC-saccharifying, filter paper-disintegrating and β-glucosidase activity were 40℃, 45℃ and 50℃ respectively.
The Km and Vmax values of CMC saccharifying activity for CMC were 0.485% and 3.10(μmole/min·㎖), and the Km and Vmax values of β-glucosidase for ONPG(o-nitrophenol glucopyranoside) were 0.944×10 exp (-3)M and 0.097(μmole/min·㎖), respectively.
The Km and Vmax values of filter paper-disintegrating activity for Avicel were determined to be 0.09% and 0.178(μmole/min·㎖), respectively. β-Glucosidase activity was competitively inhibited by glucose, and the Ki value for this enzyme was 3.54×10 exp (-3)M, CMC saccharifying activity was found to be greatly inhibited by cellobiose.
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