...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Inorganic Chemistry: A Research Journal that Includes Bioinorganic, Catalytic, Organometallic, Solid-State, and Synthetic Chemistry and Reaction Dynamics >Geometric and electrostatic study of the [4Fe-4S] cluster of adenosine-5′-phosphosulfate reductase from broken symmetry density functional calculations and extended X-ray absorption fine structure spectroscopy
【24h】

Geometric and electrostatic study of the [4Fe-4S] cluster of adenosine-5′-phosphosulfate reductase from broken symmetry density functional calculations and extended X-ray absorption fine structure spectroscopy

机译：通过破坏对称性密度泛函计算和扩展的X射线吸收精细结构光谱研究[4Fe-4S]团的5'-磷酸腺苷还原酶[4Fe-4S]簇

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

Adenosine-5′-phosphosulfate reductase (APSR) is an iron-sulfur protein that catalyzes the reduction of adenosine-5′-phosphosulfate (APS) to sulfite. APSR coordinates to a [4Fe-4S] cluster via a conserved CC-X _(～80)-CXXC motif, and the cluster is essential for catalysis. Despite extensive functional, structural, and spectroscopic studies, the exact role of the iron-sulfur cluster in APS reduction remains unknown. To gain an understanding into the role of the cluster, density functional theory (DFT) analysis and extended X-ray fine structure spectroscopy (EXAFS) have been performed to reveal insights into the coordination, geometry, and electrostatics of the [4Fe-4S] cluster. X-ray absorption near-edge structure (XANES) data confirms that the cluster is in the [4Fe-4S]2+ state in both native and substrate-bound APSR while EXAFS data recorded at ～0.1 ? resolution indicates that there is no significant change in the structure of the [4Fe-4S] cluster between the native and substrate-bound forms of the protein. On the other hand, DFT calculations provide an insight into the subtle differences between the geometry of the cluster in the native and APS-bound forms of APSR. A comparison between models with and without the tandem cysteine pair coordination of the cluster suggests a role for the unique coordination in facilitating a compact geometric structure and "fine-tuning" the electronic structure to prevent reduction of the cluster. Further, calculations using models in which residue Lys144 is mutated to Ala confirm the finding that Lys144 serves as a crucial link in the interactions involving the [4Fe-4S] cluster and APS.
机译：腺苷5'-磷酸硫酸盐还原酶（APSR）是一种铁硫蛋白，可催化腺苷5'-磷酸硫酸盐（APS）还原为亚硫酸盐。 APSR通过保守的CC-X _（〜80）-CXXC基序与[4Fe-4S]簇协调，该簇对于催化是必不可少的。尽管进行了广泛的功能，结构和光谱学研究，铁硫簇在降低APS中的确切作用仍然未知。为了了解簇的作用，已经进行了密度泛函理论（DFT）分析和扩展的X射线精细结构光谱（EXAFS），以揭示对[4Fe-4S]的配位，几何和静电的见解。簇。 X射线吸收近边缘结构（XANES）数据证实，在天然和受衬底约束的APSR中，团簇均处于[4Fe-4S] 2+状态，而EXAFS数据记录为〜0.1？分离度表明，[4Fe-4S]簇在蛋白质的天然形式和底物结合形式之间没有显着变化。另一方面，DFT计算提供了对APSR本地和APS绑定形式的群集几何之间细微差异的深入了解。具有和不具有串联半胱氨酸对配位的簇的模型之间的比较表明，独特的协调在促进紧凑的几何结构和“微调”电子结构以防止簇减少方面具有重要作用。此外，使用其中残基Lys144突变为Ala的模型进行的计算证实了这一发现，即Lys144在涉及[4Fe-4S]簇与APS的相互作用中起着至关重要的作用。

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