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Updated: Jun 29, 2026

Hot Biological Catalysis: Isothermal Titration Calorimetry to Characterize Enzymatic Reactions
Published on: April 4, 2014
Calculating reaction rate constants and estimating the efficacy of selective enzyme inhibitors
Hilde Eikemo1, Tor Skomedal, Finn Olav Levy
1Department of Pharmacology and Center for Heart Failure Research, University of Oslo, N-0316 Oslo, Norway. hilde.eikemo@medisin.uio.no
Abstract:
The dynamic steady state of a pair of forward and backward enzymatic reactions is dependent on the balance between the enzymes catalyzing the reactions. By selectively inhibiting one or more of the enzymes involved, this balance is shifted into a new steady state, making it possible to calculate the reaction rate constants after measurement of the reactants. Ideally, the inhibitors should completely eliminate either reaction, but this is often not the case. Here we present and discuss a method for calculating the reaction rate constants and, thus, for evaluating the efficacy of one or more inhibitors when introduced to a forward-backward pair of enzymatic reactions.
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