The essential trace element copper plays a key role in living systems. Its metalloproteins are involved in various reactions. The IT ononuclear blue copper type‐1 proteins take, part in electron transfer processes. Type‐2 proteins can either act as oxidases, oxygenases, dioxygenases, or superoxide dismutases, containing one copper core. Dinuclear copper centers of Type‐3 proteins are the oxygen transport system hemocyanin, oxidases and oxygenases. Due to this variety of functions copper deficiency and also abundance can cause severe damage of any life form.