对固态二极合和溶液放松数据的比较为我们提供了对蛋白质骨干动态的洞察
Veniamin Chevelkov1, Yi Xue, Rasmus Linser
1Forschunginstitut fur Molekulare Pharmakologie (FMP), Robert-Rossle-Strasse 10, 13125 Berlin, Germany.
Journal of the American Chemical Society
|March 20, 2010
概括
蛋白质动态揭示了阿尔法谱SH3域骨干中最小的纳秒到微秒运动. 然而,灵活的循环和终点表现出ns-mus动态,在溶液和固态分析中一致.
科学领域:
- 生物物理学的生物物理.
- 结构生物学 结构生物学
- 蛋白质动力学 蛋白质动力学
背景情况:
- 了解蛋白质动态对于阐明蛋白质功能至关重要.
- 纳米秒到微秒 (ns-mus) 运动在蛋白质的功能和稳定性中起着重要作用.
- 阿尔法谱SH3域是研究蛋白质动态的一个模型系统.
研究的目的:
- 调查阿尔法谱SH3域中ns-mus动态的存在和程度.
- 通过不同的实验技术和计算方法观察到的蛋白质动态进行比较.
- 为了提供一个全面的图片的蛋白质动态在一个小球状蛋白质.
主要方法:
- 溶液的分析 (15) N放松数据.
- 测量固态二极合器的测量 (1)H(N) - ((15) N.
- 在水合晶体和溶液环境中的分子动力学 (MD) 模拟.
主要成果:
- 解决方案 (15) N放松和固态 (1) H (((N) - ((15) N双极合产生类似的顺序参数模式.
- 在大多数α谱SH3域序列中观察到很少或没有ns-mus动态,特别是在结构化骨干中.
- 在蛋白质的柔性环和端子中检测到NS-mus运动的证据.
- MD模拟证实了实验结果,显示了在不同环境中的一致性.
结论:
- 阿尔法谱SH3域在其结构区域中表现出受限的ns-mus动态.
- 灵活的区域,如循环和终点,是ns-mus运动的关键地点.
- 结合溶液和固态NMR,以及MD模拟,提供了蛋白质动态的强有力的特征.
- 这些发现与最近的蛋白质动态模型相一致,这些模型来自残余二极合研究.
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