COPPER
Transition metal; two oxidation states, Cu+ and Cu2+; in enzymic activity, may move between the two states.
Discovered to be essential in animals in the 1920s.
The human body contains 70-150 mg, of which 30-40% is in the muscles, 15% in the liver, 10% in the brain and 6% in the blood.
90% of copper in the serum is bound to ceruloplasmin. Copper concentration in serum varies with age, sex, use of contraceptive pill, infections.
Copper is absorbed through the intestinal mucosa and transported – bound to albumin, transcuprein and low MW ligands (amino acids, esp. his, gln, thr, cys) – to the liver, where it is incorporated into ceruloplasmin (CP).
This is released into the blood, and is transported to cells with CP-receptors; Cu is released and enters the cells.
Linus Pauling Institute (LPI) has an extensive information center on micronutrients. The e-lectures link to useful sources on many micronutrients:
Functions of copper
Co-factor in many enzymes (e.g. tyrosinase, cytochrome oxidase, superoxide dismutase, monoamine oxidase). Essential for energy metabolism, production of connective tissue, metabolism of neuropeptides. Takes part in glucose and cholesterol metabolism. SOD is important in antioxidant defence. Involved catalytically in formation of haemoglobin.