Single‐step unimolecular non‐first‐order enzyme deactivation kinetics

Abstract

A two-parameter deactivation model is proposed to describe the kinetics of activity stabilization for some enzymes. The single-step unimolecular mechanism exhibits non-first-order deactivation kinetics since the final enzyme state, E(1) is not completely inactivated. The usefulness of the model is demonstrated by applying it to the inactivation of different enzymes. The influence of the concentration of active ester, ionic strength, and pH on the model parameters is examined during the inactivation of electric eel acetylcholinesterase.(25) In general, inactivators would decrease the level of activity stabilization, alpha(1), and increase the first-order inactivation rate constant, k(1). The effect of protecting agents would be to increase alpha(1) and to decrease k(1).

NANOBIOCATALYTIC SYSTEMS BASED ON LIPASE-Fe3O4 AND CONVENTIONAL SYSTEMS FOR ISONIAZID SYNTHESIS: A COMPARATIVE STUDY

“…The initial activity was taken as 100%. The deactivation constant and half-life (t1/2) for each immobilized derivative were calculated according to the Sadana and Henley model (Sadana and Henley, 1987;Sadana, 1988). With the exponential nonlinear decay model and its parameters, it was possible to determine the inactivation constant (kd) and the half-lives (t1/2) of the derivatives.…”

Stabilization of native penicillin G acylase by ionic liquids

“…25 In this way, a series-type deactivation model involving two firstorder steps with one active precursor and a final enzyme state with possible non-zero activity 26 was considered for analyzing PGA deactivation in ILs, as follows:…”

Chemical improvement of chitosan-modified beads for the immobilization of Enterococcus faecium DBFIQ E36 l-arabinose isomerase through multipoint covalent attachment approach

“…At different time gaps, samples were withdrawn, put into an ice bath and residual activities were properly assessed according to the methodologies proposed above. In addition, thermal stability experimental results were adjusted according to the singlestep non-first-order model proposed by Sadana and Henley [49].…”