PRODUCTION OF DNA STRAND BREAKS BY HYDROXYL RADICAL
PRODUCTION OF DNA STRAND BREAKS BY HYDROXYL RADICAL
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DOI：
10.1080/09553007414550791
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发表时间：
1974-01-01
影响因子：
2.6
通讯作者：
DURYEA, H
中科院分区：
文献类型：
--
作者：
ACHEY, P;DURYEA, H
将ϕx174DNA合成的环状共价闭合双链复制中间体(Replicative Form I，RFI)在氮气饱和水溶液中照射。在此条件下，OH·和EAQ−是主要的初级自由基，H·的产率约为其他两种的五分之一。羟基自由基清除剂亚铁氰化钾和碘化钾保护DNA免受辐射损伤。加入高锰酸钾，它与电子和氢自由基反应，提供的保护作用很小。硝酸钾是一种有效的电子自由基清除剂，对链断裂几乎没有保护作用。羟基自由基显然是水辐射分解的重要物种，参与了DNA的二次辐射损伤，表现为链断裂。这项研究的一个重要特点是，对辐射损伤的分析是在没有将DNA暴露于广泛的化学处理或未知的细胞酶的情况下进行的。
The circular covalently-closed double-stranded replicative intermediate of ϕX174 DNA synthesis (replicative form I, RFI) was irradiated in nitrogen-saturated aqueous solution. Under these conditions, OH· and eaq−are the main primary radicals and the yield of H· is approximately one-fifth of the other two species. The DNA was protected from radiation-induced strand breaks by the hydroxyl radical scavengers, potassium ferrocyanide and potassium iodide. Addition of potassium permanganate, which reacts with the electron and the hydrogen radical, afforded little protection. Potassium nitrate, which is an efficient electron radical scavenger, produced little protection against strand breaks. The hydroxyl radical is apparently the important species of water radiolysis involved in secondary radiation damage to DNA expressed as strand breaks. An important feature of this study was that the analysis for radiation damage was performed without exposure of the DNA to extensive chemical treatment or unknown cellular enzymes.