CELLULOSE-SPLITTING ENZYMES

Abstract

Crystalline cellulase is prepd. from the culture medium by fractional acetone pptns. The enzyme is active on carboxymethyl cellulose and p-nitrophenyl [beta]-cellobioside but not on salicin, cellobioside and starch. With p-nitrophenyl [beta]-cellobioside, both agluconic and holosidic bonds are split but the rate of the latter bond hydrolysis declines rapidly due to inhibition by reaction product, while the former one is split readily. The Michaelis consts. (Km) for cleavage of agluconic and holosidic bonds are 0.04 and 0.004 [image]/l, respectively. Inhibition of the enzyme by glucose, cellobiose and p-nitrophenyl [beta]-glucoside is exhibited, showing dissociation consts. of enzyme-inhibitor of 0.001, 0.0025 and 0.0024[image]/1., respectively.