Inhibition of beta-glucosidase activity in Trichoderma reesei C30 cellulase by derivatives and isomers of glucose
The inhibition of Beta-glucosidase in Trichoderma reesei C30 cellulase by D-glucose, its isomers, and derivatives was studied using cellobiose and p-nitrophenyl-beta-glucoside (PNPG) as substrates for determining enzyme activity. The enzymatic hydrolysis of both substrates was inhibited competitively by glucose with approximate K1 values of 0.5mM and 8.7mM for cellobiose and PNPG as substrate, respectively. This inhibition by glucose was maximal at pH 4.8 and no inhibition was observed at pH 6.5 and above. The alpha anomer of glucose inhibited beta-glucosidase to a greater extent than did the beta form. Compared with D-glucose, L-glucose, D-glucose-6-phosphate, and D-glucose-1-phosphate inhibited the enzyme to a much lesser extent, unlike D-glucose-L-cysteine which was almost as inhibitory as glucose itself when cellobiose was used as substrate. Fructose (2-100mM) was found to be a poor inhibitor of the enzyme. It is suggested that high rates of cellobiose hydrolysis catalyzed by beta-glucosidase may be prolonged by converting the reaction product glucose to fructose using a suitable preparation of glucose isomerase.
- Research Organization:
- Bioprocess Research and Development Group, Chemical Tech. Div. Oak Ridge National Lab. Oak Ridge, Tennessee 37830
- OSTI ID:
- 5246348
- Journal Information:
- Biotechnol. Bioeng.; (United States), Vol. 23:7
- Country of Publication:
- United States
- Language:
- English
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09 BIOMASS FUELS
ENZYMATIC HYDROLYSIS
INHIBITION
GLUCOSIDASE
BIOCHEMICAL REACTION KINETICS
CELLOBIOSE
CELLULASE
ENZYME ACTIVITY
ENZYME INHIBITORS
FRUCTOSE
GLUCOSE
SUBSTRATES
TRICHODERMA VIRIDE
ALDEHYDES
CARBOHYDRATES
CHEMICAL REACTIONS
DECOMPOSITION
DISACCHARIDES
ENZYMES
FUNGI
GLYCOSYL HYDROLASES
HEXOSES
HYDROLASES
HYDROLYSIS
KETONES
KINETICS
LYSIS
MONOSACCHARIDES
O-GLYCOSYL HYDROLASES
OLIGOSACCHARIDES
ORGANIC COMPOUNDS
PLANTS
REACTION KINETICS
SACCHARIDES
SOLVOLYSIS
TRICHODERMA
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