Selection of Metal Ions for Complexation

1953) (zinc is less than copper, but its location is not clear in this list)  

On the other hand, many substrates and inhibitors bind to protein-bound metals by the formation of such rings. 

The actual binding of a metal ion to a ligand is governed, in aqueous solution, by its competition with protons. Breslow (1973) considered a ligand-binding site, L , a protein side chain, for example, that can interact with either a hydrogen ion, H, or a metal ion, 

Breslow dehned an apparent pH-dependent constant, K, which relates the number of binding sites carrying metal [LM ] to those not carrying metal, as 

Relative Affinities of Protons, Cvfll), and Zn(H) for Protein Side Chains  

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