Effects of pH and ion binding on biochemical reaction thermodynamics

The previous section illustrated how to calculate apparent equilibrium properties for biochemical reactions expressed in terms of biochemical reactants that are sums 

The impact of K+ and Mg2+ binding on the apparent equilibrium constant may be calculated by incorporating binding of these species into the binding polynomials for the reactants in a given reaction. For example, for the ATP hydrolysis reaction, the binding polynomials for the three reactants become  

When K+ and Mg2+ binding are considered, the apparent equilibrium free energy and equilibrium constant are computed as functions of the K+- and Mg2+-dependent binding polynomials. 

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