THE ROLE OF IRON IN ASCORBATE-DEPENDENT DEOXYRIBOSE DEGRADATION - EVIDENCE CONSISTENT WITH A SITE-SPECIFIC HYDROXYL RADICAL GENERATION CAUSED BY IRON IONS BOUND TO THE DEOXYRIBOSE MOLECULE
THE ROLE OF IRON IN ASCORBATE-DEPENDENT DEOXYRIBOSE DEGRADATION - EVIDENCE CONSISTENT WITH A SITE-SPECIFIC HYDROXYL RADICAL GENERATION CAUSED BY IRON IONS BOUND TO THE DEOXYRIBOSE MOLECULE
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DOI：
10.1016/0162-0134(87)80035-1
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发表时间：
1987-04-01
影响因子：
3.9
通讯作者：
HALLIWELL, B
中科院分区：
文献类型：
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作者：
ARUOMA, OI;GROOTVELD, M;HALLIWELL, B
在pH 7.4的H2O2、抗坏血酸盐和磷酸盐缓冲液存在下，脱氧核糖被降解。降解受到过氧化氢酶、甘露醇、脱铁转铁蛋白、脱乳铁蛋白或去铁胺的抑制。在存在足够的脱铁转铁蛋白以刚好抑制脱氧核糖降解的情况下，可以通过向反应混合物中加入更多的脱氧核糖而不是通过额外的磷酸盐或抗坏血酸盐来恢复反应。有人建议，在我们的反应条件下，脱氧核糖降解是通过使用铁离子结合到脱氧核糖分子的羟基自由基的位点特异性形成。分光光度法和动力学证据铁离子结合脱氧核糖。
In the presence of H2O2, ascorbate and phosphate buffer at pH 7.4, deoxyribose is degraded. Degradation is inhibited by catalase, and mannitol, apotransferrin, apolactoferrin, or desferrioxamine. In the presence of sufficient apotransferrin to just inhibit deoxyribose degradation, reaction can be restored by adding more deoxyribose to the reaction mixture, but not by additional phosphate or ascorbate. It is suggested that deoxyribose degradation under our reaction conditions is achieved by a site-specific formation of hydroxyl radical using iron ions bound to the deoxyribose molecule. Spectrophotometric and kinetic evidence for the binding of iron ions to deoxyribose is presented.