通过大肠杆菌RcnRRR传感的Ni (II) 和Co (II) 传感
Jeffrey S Iwig1, Sharon Leitch, Robert W Herbst
1Washington University School of Medicine, Department of Biochemistry and Molecular Biophysics, Saint Louis, Missouri 63110, USA.
Journal of the American Chemical Society
|May 29, 2008
概括
大肠杆菌的RcnR蛋白与和具有高度亲和力,揭示出不同的协调位点. 这项研究澄清了细菌如何感知不同水平,并确定了金属结合特异性的关键氨基酸指纹.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- 大肠杆菌RcnR和Mycobacterium结核病CsoR是关键的细菌金属响应DNA结合蛋白.
- RcnR调节金属流量蛋白RcnA,以应对 (Ni(II)) 和 (Co(II)) 离子.
研究的目的:
- 调查Ni (II) 和Co (II) 与RcnR的相互作用,以了解它们作为全效应剂的功能.
- 阐明RcnR.中的金属结合点的结构和化学特性.
主要方法:
- 射线吸收光谱学X射线吸收光谱学
- 电子偏磁共振 (EPR) 光谱学
- 生物化学试验和生物信息学分析.
主要成果:
- 两种Ni (II) 和Co (II) 结合RcnR具有纳米分子亲和力,稳定了蛋白质.
- 对两种金属都确定了含有硫酸盐连接体的六个坐标高旋转金属位点,具有共同的N端协调图案.
- 对Ni (II) 和Co (II) 观察到不同的协调环境和M-S距离,包括一种新的Co (II) - thiolate协调.
- 确定了四种氨基酸指纹,可能决定了RcnR/CsoR蛋白家族中的联结特异性.
结论:
- 该研究描述了RcnR中的Ni (II) -和Co (II) -结合位点,突出了与CsoR和其他Ni (II) 监管者 (如NikR.
- 这些发现提供了关于大肠杆菌如何感知不同度的见解.
- 鉴定到的指纹有助于了解RcnR/CsoR蛋白家族的特异性和演变.
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