title: Kinetic modeling of cellulose hydrolysis with first order inactivation of adsorbed cellulase.
abstract: Enzymatic hydrolysis involves complex interaction between enzyme, substrate, and the reaction environment, and the complete mechanism is still unknown. Further, glucose release slows significantly as the reaction proceeds. A model based on Langmuir binding kinetics that incorporates inactivation of adsorbed cellulase was developed that predicts product formation within 10% of experimental results for two substrates. A key premise of the model, with experimental validation, suggests that V(max) decreases as a function of time due to loss of total available enzyme as adsorbed cellulases become inactivated. Rate constants for product formation and enzyme inactivation were comparable to values reported elsewhere. A value of k(2)/K(m) that is several orders of magnitude lower than the rate constant for the diffusion-controlled encounter of enzyme and substrate, along with similar parameter values between substrates, implies a common but undefined rate-limiting step associated with loss of enzyme activity likely exists in the pathway of cellulose hydrolysis.
authors: Department of Chemical Engineering, University of Louisville, Louisville, KY 40292, USA.
authors: Zhuoliang
authors: Z
authors: Ye
authors: R Eric
authors: RE
authors: Berson
mesh_terms: D000327:Adsorption; D002480:Cellulase / Q000378:metabolism*; D002482:Cellulose / Q000378:metabolism*; D005427:Flocculation; D005947:Glucose / Q000032:analysis; D006868:Hydrolysis; D007700:Kinetics; D008954:Models, Biological; D012044:Regression Analysis; D013997:Time Factors
chemical_list: D002482:Cellulose; D002480:Cellulase; D005947:Glucose