在最短的时间内进行蛋白质NMR动力学研究的极端不均采样
Gregory Jameson1,2, Alexandar L Hansen3, Dawei Li3
1Department of Chemistry and Biochemistry , The Ohio State University , Columbus , Ohio 43210 , United States.
Journal of the American Chemical Society
|September 28, 2019
概括
这项研究引入了一种加速15N化学交换和转移 (CEST) NMR实验的新方法,使用优化非均采样 (NUS). 这种方法显著加快了蛋白质动态测量,同时最大限度地减少了人工物.
科学领域:
- 核磁共振 (NMR) 光谱学
- 蛋白质动力学
- 生物物理化学
背景情况:
- 通过自旋放松或化学交换和转移 (CEST),NMR光谱为蛋白质动力学提供了定量见解.
- 标准的15N-CEST测量由于长时间的伪3DHSQC实验而耗时.
- 非统一采样 (NUS) 可以加快这些实验,但往往会引入缺陷,优化仍然是一个挑战.
研究的目的:
- 为15N-CEST实验优化NUS时间表制定和验证一个系统方法.
- 显著减少量化多维NMR研究的测量时间.
- 尽量减少与加速NMR数据采集相关的文物.
主要方法:
- 使用2DHSQC参考实验中的装配交叉峰作为"足迹"来重建伪3DCEST数据.
- 采用线性最小正方形适配来确定交叉峰幅作为射频偏移 (Δω) 的函数.
- 实施基于克拉默-拉奥下界度的频谱优化非统一采样方案 (SONUS).
主要成果:
- 在获取Im7蛋白质的高度准确的CEST配置文件方面实现了20-30倍的速度.
- 证明使用参考实验交叉峰值来重建不足样本数据的有效性.
- 通过SONUS确定最佳采样计划的一般性质.
结论:
- 开发的方法可显著加快定量多维NMR测量.
- 这种针对15N-CEST的NUS时间表的系统优化可以最大限度地减少错误和错误.
- 这些发现为在溶液中更有效的蛋白质动态研究铺平了道路.
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