Question

What are all the proteins other than metallothioneins for binding of heavy metals?

Answer 1

Both essential (zinc and copper) and nonessential (cadmium and mercury) metals can induce the synthesis of metallothioneins and also constitute part of the molecule. Thus, these proteins have a role in the metabolism of essential metals and protection against the toxicity of metals.Heavy metals denature the biological activity of native, folded proteins through diverse modes of interaction; they may: bind to free thiols or other functional groups in proteins; displace essential metal ions in metalloproteins; catalyze oxidation of amino acid side chains.Metallothionein is a cytoplasmic protein, in an adult liver, it is localized mainly in the cytoplasm. In human fetus, metallothionein is localized in hepatocyte nuclei.