A kinetic approach to the evaluation of alkaline phosphatase inactivation by urea

A kinetic approach is described which enables the measurement of the enzyme inactivation rate constant during the reaction course. A mathematical analysis is presented and it is shown that a time-dependent step may be postulated to exist. Reaction kinetics follow an exponential rule with time as the independent variable and enzymatic activity as the dependent variable. A simple procedure of graphical analysis is reported and the influence on the inactivation rate constant of various conditions (temperature and inhibitor concentration) is evaluated. The method is illustrated by an experimental model: the inactivation of bovine kidney alkaline phosphatase by urea.