Strand breaks, base release, and postirradiation changes in DNA gamma-irradiated in dilute O2-saturated aqueous solution.
Strand breaks, base release, and postirradiation changes in DNA gamma-irradiated in dilute O2-saturated aqueous solution.
复制标题
稀 O2 饱和水溶液中经 γ 照射的 DNA 的链断裂、碱基释放和照射后变化。
DOI：
10.2307/3574453
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发表时间：
1976
影响因子：
3.4
通讯作者：
I. Kuo
中科院分区：
文献类型：
--
作者：
J. Ward;I. Kuo
..伽马.. -在稀释的O/sub 2/-饱和水溶液中照射DNA会从大分子中释放出游离碱基和受损碱基。经柱层析分离后测定这些产物的产率。对于双链DNA，碱基的直接产率从胞嘧啶的G = 0.012到腺嘌呤的G = 0.033不等。释放的碱的产率随辐射后时间增加（大部分增加发生在前2小时），产率在G = 0.07至± 0.012的范围内。两个释放的受损胸腺嘧啶辐射产物的产量从...伽马.. -照射后1h/sup 3/H胸腺嘧啶标记的DNA也随照射后时间的延长而增加。测量股线断裂。伽马.. -照射的单链DNA;初始产率G = 0.02低，但随时间增加至G = 0.07。链断裂的产生和低分子量产物的释放之间不可能有直接的相关性。研究结果进行了讨论，在体内的DNA损伤和酶修复。
..gamma..-Irradiation of DNA in dilute O/sub 2/-saturated aqueous solution releases free bases and damaged bases from the macromolecule. The yields of these products were measured after column chromatographic separation. For double-stranded DNA the immediate yield of bases varies from G = 0.012 for cytosine to G = 0.033 for adenine. The yields of released bases increase with postirradiation time (the majority of the increase occurs in the first 2 hr) to yields in the range of G = 0.07 to +-0.012. Yields of two released damaged thymine radiation products from ..gamma..-irradiated /sup 3/H thymine-labeled DNA also increased with postirradiation time. Strand breaks were measured in ..gamma..-irradiated single-stranded DNA; the initial yield G = 0.02 was low but increased with time to G = 0.07. No direct correlation between strand-break production and release of products of low molecular weight is possible. The findings are discussed in terms of damage to DNA in vivo and its enzymatic repair.