如何通过同核核核磁共振检测内部运动
Jürgen Schleucher1, Sybren S Wijmenga
1Department of Medical Biochemistry and Biophysics, and Department of Organic Chemistry, Umeå University, S-90187 Umeå, Sweden. jurgen@rabbit.chem.umu.se
Journal of the American Chemical Society
|May 16, 2002
概括
这项研究引入了一种非共振ROESY方法,通过分析交叉峰值强度来测量分子内部运动. 该技术揭示了对蛋白质动态的详细见解,适用于不需要同位素标记的高达15kDa的分子.
科学领域:
- 结构生物学 结构生物学
- 生物物理化学 生物物理化学
- 核磁共振光谱学 核磁共振光谱学
背景情况:
- 核重复效应光谱 (NOESY) 和旋重复效应光谱 (ROESY) 的交叉峰强度受核间距离和分子运动的影响.
- 内部分子运动经常被忽视,NOESY数据仅被解释为核间距离.
研究的目的:
- 开发和验证一种使用异共振 ROESY 来量化分子内部运动的方法.
- 评估该方法对分析蛋白质动态及其适用于高达15kDa的分子的实用性.
主要方法:
- 使用非共振ROESY实验来测量NOE和ROE的加权平均值,由角theta控制.
- 开发了一个协议来测量theta;(0) 从一系列的异共振ROESY光谱,分析个别的交叉峰值,以评估特定的H,H向量的内部运动.
- 将该方法应用于蛋白质BPTI,分析了75个交叉峰,以确定theta;(0) 值及其精度.
主要成果:
- 场外共振ROESY方法成功确定了theta;(0) 值,反映了整体和内部分子运动.
- 在100-300 ps的时间尺度上,内部运动显示了theta的最大减少;(0).
- 对BPTI的分析显示,刚性区域的theta;(0) 定义很好,在灵活区域和甲基组中确定了动态,与已知的时间尺度一致.
结论:
- 非共振ROESY提供了一种监测内部分子运动的敏感方法,特别适用于结构计算中的H,H接触.
- 该技术适用于大约15kDa的分子,不需要同位素标记,将其应用扩展到天然产品.
- 该方法提供了精确的分子动力学的测量,补充了现有的结构生物学技术.
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