Carbamylation inhibits the ferroxidase activity of caeruloplasmin.
The ferroxidase activity of caeruloplasmin (EC 1.16.3.1) is an important antioxidant defence mechanism in man. In chronic renal failure proteins become carbamylated as a result of reactions with urea-derived cyanate. We have therefore investigated the effects of carbamylation on the ferroxidase activity of caeruloplasmin. Increasing degrees of carbamylation produce a progressive impairment of ferroxidase activity measured using o-dianisidine as substrate, and the ability of caeruloplasmin to load ferrous iron onto ovotransferrin is reduced. Carbamylation of caeruloplasmin may contribute to reduced antioxidant capacity in patients with renal failure.
Roxborough
H E
HE
Department of Clinical Biochemistry, Queen's University of Belfast, Northern Ireland.
Millar
C A
CA
McEneny
J
J
Young
I S
IS
D002570:Ceruloplasmin / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism*; D003207:Conalbumin / Q000378:metabolism; D003485:Cyanates / Q000378:metabolism / Q000494:pharmacology*; D006801:Humans; D007501:Iron / Q000378:metabolism; D007676:Kidney Failure, Chronic / Q000201:enzymology; D007700:Kinetics; D013997:Time Factors
D003485:Cyanates; D003207:Conalbumin; D007501:Iron; D002570:Ceruloplasmin