THE EFFECT OF PH ON ENZYME ACTIVITY

Abstract

This article provides a comprehensive biochemical and physicochemical analysis of the effect of pH on enzyme activity. The properties of enzymes as protein-based biological catalysts, the structure of their active centers, and the dependence of ionizable functional groups on the acidity of the medium are discussed. The pH value is explained as the negative logarithm of hydrogen ion concentration according to the equation pH = −log [H+], and the ionization equilibrium of water is described by the reaction H₂O ↔ H+ + OH−. The mechanism of enzyme–substrate complex formation is presented through the scheme E + S ↔ ES → E + P, and the influence of pH changes on the protonation and deprotonation states of amino acid side chains is clarified. Furthermore, the concepts of optimal pH, enzyme denaturation, the role of buffer solutions, and mechanisms maintaining pH stability in biological systems are scientifically substantiated. The results demonstrate the high sensitivity of enzymes to pH changes and confirm that environmental stability is a crucial factor in cellular life processes.