Chiou S H
J Biochem. 1983 Oct;94(4):1259-67. doi: 10.1093/oxfordjournals.jbchem.a134471.
L-Ascorbic acid, when combined with either copper(II) ion or a copper(II)-tripeptide complex, extensively cleaved several viral DNAs and proteins under in vitro conditions. Neither ascorbate nor copper tripeptide (Cu2+-diglycyl-L-histidine) alone caused any apparent changes on these molecules. Various transition metal ions and reducing agents were examined under comparable conditions to determine the basic requirements for both DNA degradation and protein scission activities. Copper and iron are the two most effective transition metal ions examined that exhibit these activities in the presence of ascorbate. The addition of catalase, but not superoxide dismutase, can partially inhibit the scission of DNA in vitro, suggesting that H2O2 may be involved in these activities. Among the various reducing agents tested, ascorbate was most effective in causing DNA scission and protein cleavage, corroborating the possible role of H2O2 in the cleavage reactions. One of the products of the reactions of copper/ascorbate is probably the hydroxyl radical generated from H2O2, which can be formed from the oxidation of ascorbate.
在体外条件下，L-抗坏血酸与铜（II）离子或铜（II）-三肽复合物结合时，能广泛切割多种病毒DNA和蛋白质。单独的抗坏血酸盐或铜三肽（Cu2+-二甘氨酰-L-组氨酸）对这些分子均未引起任何明显变化。在可比条件下检测了各种过渡金属离子和还原剂，以确定DNA降解和蛋白质裂解活性的基本要求。铜和铁是所检测的两种最有效的过渡金属离子，在抗坏血酸盐存在下表现出这些活性。添加过氧化氢酶而非超氧化物歧化酶可部分抑制体外DNA的裂解，这表明H2O2可能参与了这些活性。在所测试的各种还原剂中，抗坏血酸盐在引起DNA裂解和蛋白质切割方面最有效，这证实了H2O2在裂解反应中可能起的作用。铜/抗坏血酸反应的产物之一可能是由H2O2产生的羟基自由基，它可由抗坏血酸的氧化形成。
