不同类型的小振幅平面动力学在残余二极合的蛋白质中
Pau Bernadó1, Martin Blackledge
1Institut de Biologie Structurale Jean-Pierre Ebel, UJF-CNRS-CEA, 41 rue Jules Horowitz, 38027 Grenoble Cedex, France.
Journal of the American Chemical Society
|April 15, 2004
概括
小幅度蛋白质动态显著影响剩余二极合 (RDC). 纳入高斯轴波动 (GAF) 运动可以改善对齐张量分析,并揭示其他NMR方法无法轻松检测到的骨干动力学.
科学领域:
- 结构生物学 结构生物学
- 核磁共振 (NMR) 光谱学 核磁共振 (NMR) 光谱学
- 计算生物物理学的计算生物物理学
背景情况:
- 剩余二极合 (RDCs) 对蛋白质动态非常敏感.
- 非同位素平面运动可以影响RDC测量.
- 高斯轴的波动 (GAF) 描述了蛋白质的骨干动力学.
研究的目的:
- 为了研究小振幅异性质平面运动对RDCs的影响.
- 开发一种分析方法,将GAF运动纳入RDC分析.
- 为了确定蛋白质二次结构和循环中的GAF平均幅度.
主要方法:
- 开发了包括GAF运动在内的平均N-(N) H RDCs的分析描述.
- 纳入运动幅度 (sigma) 作为对齐张量分析中的附加参数.
- 将该方法应用于来自五种蛋白质和酶结构的实验N-(N) H RDC数据.
主要成果:
- GAF运动显著影响RDC的平均值,取决于平面的方向和运动幅度.
- 二次结构的平均GAF幅度 (sigma ((av)) 从14.4到17.0度不等.
- 循环区域在lyszyme中显示出更高的20度的sigma (av),在不同的晶体分辨率中获得了强大的结果.
结论:
- 该GAF模型提供了一个更准确的对齐张量大小的定义.
- 该方法使用可访问的NMR数据检测平均小幅度蛋白质骨干运动.
- GAF运动分析提供了对蛋白质动态的洞察,其时间尺度不易通过其他技术取样.
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