REACTION OF FREE RADICAL METABOLITES WITH DNA

自由基代谢物与DNA的相互作用一直是一个重要的领域 引起人们的兴趣和猜测，但之前的电子自旋共振(ESR) 对这一地区的调查一直非常有限。他们的反应 羟基自由基，由Fenton体系与嘧啶生成 用自旋电子自旋共振技术研究脱氧核糖核苷酸 诱捕。利用自旋陷阱t-亚硝基丁烷捕获二次 由羟基自由基与这些化合物反应形成的自由基 核苷酸。这里给出的结果表明，羟基自由基对 胸苷、2-脱氧胞苷、5-单磷酸和2-脱氧尿苷 5-单磷酸产生核苷酸衍生的自由基。结果是 表明OH自由基的攻击主要发生在碳-碳键上 嘧啶碱基的双键。ESR研究表明， 与使用x射线或伽马射线的作者以前的工作的相关性 辐射产生羟基自由基。硫代巴比妥酸测定法 也被用来监测由 芬顿系统。这些结果显示与自旋定性一致。 诱捕研究。

The interaction of free radical metabolites with DNA has been a major area of interest and speculation, but previous electron spin resonance (ESR) investigations of this area have been very limited. The reaction of the hydroxyl radical, generated by a Fenton system, with pyrimidine deoxyribonucleotides was investigated using the ESR technique of spin trapping. The spin trap t-nitrosobutane was employed to trap secondary radicals formed by the reaction of the hydroxyl radical with these nucleotides. The results presented here show the hydroxyl radical attack on thymidine, 2-deoxycytidine 5-monophosphate and 2-deoxyuridine 5-monophosphate produced nucleotide-derived free radicals. The results indicate that OH radical attack occurs predominantly at the carbon-carbon double bond of the pyrimidine base. The ESR studies showed a good correlation with previous work produced by authors who used x- or gamma-ray irradiation to generate the hydroxyl radical. A thiobarbituric acid assay was also used to monitor the damage produced to the nucleotides by the Fenton system. These results showed qualitative agreement with the spin trapping studies.