Roxborough H E, Millar C A, McEneny J, Young I S
Department of Clinical Biochemistry, Queen's University of Belfast, Northern Ireland.
Biochem Biophys Res Commun. 1995 Sep 25;214(3):1073-8. doi: 10.1006/bbrc.1995.2395.
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.
铜蓝蛋白（EC 1.16.3.1）的亚铁氧化酶活性是人体重要的抗氧化防御机制。在慢性肾衰竭中，蛋白质会因与尿素衍生的氰酸盐反应而发生氨甲酰化。因此，我们研究了氨甲酰化对铜蓝蛋白亚铁氧化酶活性的影响。使用邻联茴香胺作为底物测定时，随着氨甲酰化程度的增加，亚铁氧化酶活性逐渐受损，并且铜蓝蛋白将亚铁离子加载到卵转铁蛋白上的能力降低。铜蓝蛋白的氨甲酰化可能导致肾衰竭患者抗氧化能力下降。
