...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Proceedings of the National Academy of Sciences of the United States of America >The Mo-Se active site of nicotinate dehydrogenase
【24h】

The Mo-Se active site of nicotinate dehydrogenase

机译：烟酸脱氢酶的Mo-Se活性位点

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

Nicotinate dehydrogenase (NDH) from Eubacterium barkeri is a molybdoenzyme catalyzing the hydroxylation of nicotinate to 6-hydroxynicotinate. Reactivity of NDH critically depends on the presence of labile (nonselenocysteine) selenium with an as-yet-unidentified form and function. We have determined the crystal structure of NDH and analyzed its active site by multiple wavelengths anomalous dispersion methods. We show that selenium is bound as a terminal Mo=Se ligand to molybdenum and that it occupies the position of the terminal sulfido ligand in other molybdenum hydroxylases. The role of selenium in catalysis has been assessed by model calculations, which indicate an acceleration of the critical hydride transfer from the substrate to the selenido ligand in the course of substrate hydroxylation when compared with an active site containing a sulfido ligand. The MoO(OH)Se active site of NDH shows a novel type of utilization and reactivity of selenium in nature.
机译：来自巴氏真细菌的烟酸脱氢酶（NDH）是一种钼酸酶，催化烟酸羟基化为6-羟基烟酸。 NDH的反应性主要取决于不稳定形式（非硒代半胱氨酸）硒的存在，其形式和功能尚未确定。我们已经确定了NDH的晶体结构，并通过多种波长异常分散方法分析了其活性位点。我们表明，硒被绑定为钼的末端Mo = Se配体，并且它在其他钼羟化酶中占据末端硫基配体的位置。硒在催化中的作用已通过模型计算进行了评估，与包含硫代配体的活性位点相比，该计算表明在底物羟基化过程中，临界氢化物从底物向硒代配体的临界氢化物转移加速。 NDH的MoO（OH）Se活性位点显示出自然界中硒的一种新型利用和反应性。

著录项

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