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Updated: Oct 16, 2025

Unraveling Entropic Rate Acceleration Induced by Solvent Dynamics in Membrane Enzymes
Published on: January 16, 2016
Mathematical Description of the Enzymatic Activity of Proteins with Ionizable Groups Exhibiting Deviations from the
Luis Fernando Mercier Franco1, Pedro de Alcantara Pessoa Filho2
1Chemical Engineering School, University of Campinas, Av. Albert Einstein, 500, Campinas, SP, 13083-852, Brazil.
Abstract:
The ionization equilibrium implied in the calculation of the specific activity is classically described through the Henderson-Hasselbalch equation. An extension for the description of anomalous ionization profiles using the Hill equation is presented in this communication. The proposed framework was applied to the description of the specific enzymatic activity curve as a function of pH of five enzymes presenting different ionization states in their active site. The developed equation improves the description of relative enzymatic curves that deviate from the bell curve predicted by the application of the Henderson-Hasselbalch equation, regardless of the ionization scheme related to the active site.
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