Metal Complexes with Amino Acids

In animals, free amino acids play an important role in the complexation of metal ions. The toxicity of such ions is decreased by chelation. Metals are often transported as amino acid complexes, which are generally governed by complex equilibria. The binding of metal ions changes the pK values of amino acids, which can in turn be used for activation.

 

Examples of simple chelate complexes with amino acids:

Glycine

[Ni(Glycinate)3]-: Anionic tris-complex with a pseudo-octahedral coordination environment for the metal (without H-atoms)

Cu(II)-
Complex

Ni(II)-
Complex 1

Ni(II)-
Complex 2

Zn(II)-
Complex

To the examples for: Cysteine, Histidine, Methionine