乌米亚宁的活性部位结构,是根根中的星素
Christopher Dennison1, Mark D Harrison
1School of Natural Sciences, Bedson Building, University of Newcastle upon Tyne, Newcastle upon Tyne, NE1 7RU, UK. christopher.dennison@ncl.ac.uk
Journal of the American Chemical Society
|February 26, 2004
概括
这项研究使用了偏磁性NMR来分析铜蛋白质乌米亚宁. 结果显示,它有一个典型的1型铜位点,轴性谷氨胺连接体通过其胺氧协调.
科学领域:
- 生物化学 生物化学
- 生物有机化学 生物有机化学
- 结构生物学 结构生物学
背景情况:
- 素具有1型铜位点与His(2) Cys赤道连接体和轴向Met,通常导致扭曲的四面体几何形状.
- 乌米亚宁 (UMC) 是一种带有轴性谷氨胺 (Gln) 连接体的恒星亚宁变体,与常见的氨 (Met) 连接体不同.
研究的目的:
- 为了研究乌米亚宁 (UMC) 的活性位结构,特别是其1型铜位的协调环境.
- 在UMC中使用偏磁性NMR光谱学来确定轴性Gln配体的协调模式.
- 为了比较UMC与其他铜素的活性部位结构,并了解结构变化的影响.
主要方法:
- 参磁性 (1) H 核磁共振光谱学被用来研究乌米 ([Ni(II) UMC]) 的铜(II) 和(II) 衍生物.
- 进行了光谱分配,以识别和分析来自活性位点连接体的共振.
- 研究了性过渡对蛋白质结构和连接物协调的影响.
主要成果:
- 分配的NMR光谱证实了Cu(II) UMC的His(2) Cys赤道协调集,与典型的1型铜位相一致.
- 在Cu(II) UMC中没有观察到来自轴联体的偏磁转移共振,这表明它与单独占用的分子轨道 (SOMO) 不具有显著的相互作用.
- Ni(II) UMC 的偏磁性核磁共振显示,轴向的 Gln 连接体通过其侧链胺氧原子单坐标.
- 性过渡影响了结合残留物,但没有改变 Gln 结合物的协调模式.
结论:
- 乌米亚宁具有经典的1型铜位点,尽管其轴联体与其他恒星亚宁相比有差异.
- 在UMC中,轴性Gln连接体通过其胺氧来协调,并且不会显著地影响铜中心的电子结构.
- 与其他星氨酸相比,UMC的结构差异不会显著改变其1型铜位点的磁性 NMR 光谱特征.
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