• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Nature >Watching DNA polymerase η make a phosphodiester bond
【24h】

Watching DNA polymerase η make a phosphodiester bond

机译：观看DNA聚合酶η形成磷酸二酯键

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

DNA synthesis has been extensively studied, but the chemical reaction itself has not been visualized. Here we follow the course of phosphodiester bond formation using time-resolved X-ray crystallography. Native human DNA polymerase η, DNA and dATP were co-crystallized at pH6.0 without Mg~(2+). The polymerization reaction was initiated by exposing crystals to 1 mM Mg~(2+) at pH7.0, and stopped by freezing at desired time points for structural analysis. The substrates and two Mg~(2+) ions are aligned within 40 s, but the bond formation is not evident until 80 s. From 80 to 300 s structures show a mixture of decreasing substrate and increasing product of the nucleotidyl-transfer reaction. Transient electron densities indicate that deprotonation and an accompanying C2'-endo to C3'-endo conversion of the nucleophile 3'-OH are rate limiting. A third Mg~(2+) ion, which arrives with the new bond and stabilizes the intermediate state, may be an unappreciated feature of the two-metal-ion mechanism.
机译：DNA合成已被广泛研究，但化学反应本身尚未显现。在这里，我们遵循使用时间分辨X射线晶体学形成磷酸二酯键的过程。天然人DNA聚合酶η，DNA和dATP在无Mg〜（2+）的pH6.0下共结晶。通过将晶体在pH7.0下暴露于1 mM Mg〜（2+）引发聚合反应，并在所需的时间点冻结​​以进行结构分析以终止聚合反应。基板和两个Mg〜（2+）离子在40 s内对齐，但直到80 s才形成键。从80到300 s的结构显示出底物减少和核苷酸转移反应产物增加的混合物。瞬态电子密度表明亲核体3'-OH的去质子化和伴随的C2'-内向C3'-内向转化是速率限制。带有新键并稳定中间状态的第三Mg〜（2+）离子可能是双金属离子机理的一个未知特征。

著录项

  • 来源
    《Nature》 |2012年第7406期|p.196-201|共6页
  • 作者

    Teruya Nakamura; Ye Zhao; Yuriko Yamagata; Yue-jin Hua; Wei Yang;

  • 作者单位

    Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto 862-0973, Japan;

    Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA, Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou 310029, China;

    Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto 862-0973, Japan;

    Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou 310029, China;

    Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA;

  • 收录信息 美国《科学引文索引》(SCI);美国《工程索引》(EI);美国《生物学医学文摘》(MEDLINE);美国《化学文摘》(CA);
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号