Relating K, to Binding Energy

The Kd for inhibition (i.e., K, or aK,) can be directly related to the free energy of binding to the specific enzyme form as 

As noted in Chapter 2, the Gibbs free energy is composed of both an enthalpic and an entropic term. For reversible binding interactions, we can use the equality AG = AH - TAS, together with Equation (3.8) and a little algebra to obtain 

Source The plot was simulated based on data reported by Lai et al. (2000). 

4 Potential Advantages and Disadvantages of Different Inhibition Modalities In Vivo 

Chapter 3 Reversible Modes of Inhibitor Interactions with Enzymes 

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