A theoretical analysis of cellulase product inhibition: Effect of cellulase binding constant, enzyme/substrate ratio, and β‐glucosidase activity on the inhibition pattern

Theoretical analysis of cellulase product inhibition (by cellobiose and glucose) has been performed in terms of the mathematical model for enzymatic cellulose hydrolysis. The analysis showed that even in those cases when consideration of multienzyme cellulase system as one enzyme (cellulase) or two enzymes (cellulase and β‐glucosidase) is valid, double‐reciprocal plots, usually used in a product inhibition study, may be nonlinear, and different inhibition patterns (noncompetitive, competitive, or mixed type) may be observed. Inhibition pattern depends on the cellulase binding constant, enzyme concentration, maximum adsorption of the enzyme (cellulose surface area accessible to the enzyme), the range in which substrate concentration is varied, and β‐glucosidase activity. A limitation of cellulase adsorption by cellulose surface area that may occur at high enzyme/substrate ratio is the main reason for nonlinearity of double‐reciprocal plots. Also, the results of calculations showed that material balance by substrate, which is usually neglected by researchers studying cellulase product inhibition, must be taken into account in kinetic analysis even in those cases when the enzyme concentration is rather low. © 1992 John Wiley & Sons, Inc.

[1]  A. Converse,et al.  Adsorption of cellulase from Trichoderma reesei on cellulose and lignacious residue in wood pretreated by dilute sulfuric acid with explosive decompression , 1990, Biotechnology and bioengineering.

[2]  F. Rombouts,et al.  The cellulase of Trichoderma viride , 1985 .

[3]  Michael R. Ladisch,et al.  Process considerations in the enzymatic hydrolysis of biomass , 1983 .

[4]  M. Holtzapple,et al.  Determining the inhibition constants in the HCH‐1 model of cellulose hydrolysis , 1984, Biotechnology and bioengineering.

[5]  L. Fan,et al.  Kinetic studies of enzymatic hydrolysis of insoluble cellulose: (II). Analysis of extended hydrolysis times , 1983, Biotechnology and bioengineering.

[6]  A. Gusakov,et al.  Enzymatic saccharification of industrial and agricultural lignocellulosic wastes , 1992 .

[7]  A. Gusakov,et al.  Kinetics of the enzymatic hydrolysis of cellulose: 1. A mathematical model for a batch reactor process , 1985 .

[8]  T. Wood,et al.  Purification and some properties of a (1→4)-β-d-glucan glucohydrolase associated with the cellulase from the fungus Penicillium funiculosum , 1982 .

[9]  H. van Tilbeurgh,et al.  Limited proteolysis of the cellobiohydrolase I from Trichoderma reesei , 1986 .

[10]  Alexander V. Gusakov,et al.  Effect of structural and physico-chemical features of cellulosic substrates on the efficiency of enzymatic hydrolysis , 1991 .

[11]  J. Vandekerckhove,et al.  Studies of the cellulolytic system of Trichoderma reesei QM 9414. Analysis of domain function in two cellobiohydrolases by limited proteolysis. , 1988, European journal of biochemistry.

[12]  D. Wilson,et al.  Cloning of the Thermomonospora fusca Endoglucanase E2 Gene in Streptomyces lividans: Affinity Purification and Functional Domains of the Cloned Gene Product , 1988, Applied and environmental microbiology.

[13]  A. Gusakov,et al.  A product inhibition study of cellulases from Trichoderma longibrachiatum using dyed cellulose , 1985 .

[14]  Mark Holtzapple,et al.  Inhibition of Trichoderma reesei cellulase by sugars and solvents , 1990, Biotechnology and bioengineering.

[15]  S. Shoemaker,et al.  Characterization and Properties of Cellulases Purified from Trichoderma Reesei Strain L27 , 1983, Bio/Technology.

[16]  A. Klyosov,et al.  Adsorption of high-purity endo-1,4-β-glucanases from Trichoderma reesei on components of lignocellulosic materials: Cellulose, lignin, and xylan , 1988 .

[17]  M. Mandels,et al.  Cellulases: Biosynthesis and applications , 1980 .

[18]  T. K. Ghose.  Measurement of cellulase activities , 1987 .

[19]  The Comparative Role of Exoglucosidase and Cellobiase in Glucose Formation from Cellulose , 1980 .

[20]  R. Patil,et al.  β-d-glucosidases of Sclerotium rolfsii. Substrate specificity and mode of action , 1983 .

[21]  L. Fan,et al.  Mechanism of the enzymatic hydrolysis of cellulose: Effects of major structural features of cellulose on enzymatic hydrolysis , 1980 .