title: alpha-Chymotrypsin deacylation: temperature dependence of hydrolysis and transesterification reactions.
abstract: The hydrolysis and transesterification reactions of furoyl-chymotrypsins display nonlinear Arrhenius plots with no apparent discontinuities. Of a number of models considered, the best explanation assumes a temperature-dependent rapid equilibrium between two forms of acyl-enzyme with differing reactivities. Rate constants for the transesterification of alpha-chymotrypsinyl 2-(5-n-propyl)furoate, after normalization for this equilibrium, display a linear free energy correlation with the Taft polarity constants sigma* and volumes of the attacking alcohols.
mesh_terms: D000215:Acylation; D002918:Chymotrypsin / Q000378:metabolism*; D006868:Hydrolysis; D007700:Kinetics; D013696:Temperature; D013816:Thermodynamics
chemical_list: D002918:Chymotrypsin