BIOTECHNOLOGY - V. H. Herasymenko - 2006

Part II. Special Biotechnologies

Chapter 7. BIOTECHNOLOGY FOR THE PRODUCTION AND APPLICATION OF IMMOBILIZED PREPARATIONS

7.6. PHYSICOCHEMICAL CHARACTERISTICS OF THE IMMOBILIZED ENZYME

A physicochemical characteristic of an immobilized enzyme is its stability. Enzyme stability refers to The ability to retain catalytic activity under given conditions. It is determined by The Structure of the enzyme itself, as well as The Nature of its interaction with surrounding particles in solution, On the surface, within the support, or throughout the polymer gel matrix.

A quantitative measure of enzyme stability is the monomolecular Enzyme inactivation rate constant (Кін). In practice, researchers either use the inactivation rate constant determined at a specific stage of inactivation (50% or 75%) or consider the time required for the enzyme activity to decrease by half (i.e., the half-life or half-inactivation time of the enzyme).

Enzyme stability is also evaluated by its residual activity following incubation for a set period at a specific Temperature or in the presence of a denaturing agent. Enzyme stabilization refers to a reduction in the enzyme inactivation rate constant.

The stabilization or destabilization effect is assessed by comparing the Кін of the initial (native) enzyme with that of its immobilized form at a given temperature.