THE ROLE OF SUPEROXIDE AND HYDROXYL RADICALS IN THE DEGRADATION OF DNA AND DEOXYRIBOSE INDUCED BY A COPPER-PHENANTHROLINE COMPLEX
THE ROLE OF SUPEROXIDE AND HYDROXYL RADICALS IN THE DEGRADATION OF DNA AND DEOXYRIBOSE INDUCED BY A COPPER-PHENANTHROLINE COMPLEX
复制标题
DOI：
10.1016/0006-2952(82)90136-8
复制
发表时间：
1982-01-01
影响因子：
5.8
通讯作者：
HALLIWELL, B
中科院分区：
文献类型：
--
作者：
GUTTERIDGE, JMC;HALLIWELL, B
研究了在NADH、2-巯基乙醇或次黄嘌呤和黄嘌呤氧化酶的混合物存在下，Cu ~（2+）邻菲咯啉络合物对DNA的降解作用。在所有情况下，降解被防止过氧化氢酶，但不是由羟基自由基，OH的清除剂。然而，仍然有可能是OH。它与DNA紧密结合，因此在它发生反应之前，清道夫无法将其清除。超氧化物歧化酶抑制DNA降解在低浓度的Cu 2 +-菲咯啉在NADH或次黄嘌呤-黄嘌呤氧化酶的存在下，但在更高的复杂浓度。超氧化物歧化酶在2-巯基乙醇存在下对DNA降解的影响很小。探讨了O2自由基在Cu ~（2+）-邻菲咯啉诱导DNA降解中的作用。[DNA通过Cu 2 +-菲咯啉的降解是令人感兴趣的，因为它可以解释为什么菲咯啉抑制DNA和RNA聚合酶的作用，并且因为它的作用机制可以代表由药物博来霉素和他利霉素产生的[脊椎动物] DNA断裂的简单模型。
DNA degradation by a Cu2+ phenanthroline complex was studied in the presence of NADH, 2-mercaptoethanol or a mixture of hypoxanthine and xanthine oxidase, which generates the superoxide radical, O2.-. In all cases degradation was prevented by catalase but not by scavengers of the hydroxyl radical, OH.. It remains possible, however, that OH. was generated in close association with DNA so that the scavengers could not remove it before it reacted. Superoxide dismutase inhibited DNA degradation at low Cu2+-phenanthroline concentrations in the presence of NADH or hypoxanthine-xanthine oxidase, but not at higher complex concentrations. Superoxide dismutase had little effect on DNA degradation in the presence of 2-mercaptoethanol. The role of O2 radicals in the DNA degradation induced by Cu2+-phenanthroline is discussed. [DNA degradation by Cu2+-phenanthroline is of interest because it may explain why phenanthroline inhibits the action of DNA and RNA polymerases and because its mechanism of action may represent a simple model for the [vertebrate] DNA scission produced by the antineoplastic drugs bleomycin and talisomycin.].