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研究领域。 主要领域的兴趣和猜测，但以前的电子自旋 共振（ESR）研究这一领域已经非常有限。 通过芬顿系统产生的羟基自由基的反应， 与嘧啶脱氧核糖核苷酸的ESR研究 自旋捕获技术。 自旋阱t-亚硝基丁烷是 用于捕获由反应形成的次级自由基， 羟基与这些核苷酸。 呈现的结果 这里显示羟基自由基攻击胸苷，2-脱氧胞苷 5-产生的2-脱氧尿苷5-单磷酸和2-脱氧尿苷5-单磷酸 核苷酸衍生的自由基。 结果表明， 自由基攻击主要发生在碳-碳双键上 嘧啶碱基的键。 ESR研究显示， 与使用x- or的作者以前的工作的相关性 γ射线照射产生羟基自由基。 一 硫代巴比妥酸法检测损伤程度 通过芬顿系统生成核苷酸。 这些结果 与自旋捕获研究定性一致。

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.