在HIV-1状蛋白组件的NMR中以快速魔力角度旋转的动态核极化
Manman Lu1,2,3, Mingzhang Wang1,2, Ivan V Sergeyev4
1Department of Chemistry and Biochemistry , University of Delaware , Newark , Delaware 19716 , United States.
Journal of the American Chemical Society
|March 16, 2019
概括
动态核极化 (DNP) 显著提高了HIV-1囊蛋白组合的19F魔角旋转 (MAS) NMR灵敏度. 这一突破使得大型生物分子的结构分析成为可能.
科学领域:
- 生物物理
- 结构生物学
- 核磁共振光谱学
背景情况:
- 艾滋病毒-1囊蛋白 (CA) 组件对病毒结构和功能至关重要.
- 确定像HIV-1 CA这样的大型生物分子组件的结构是常规NMR的挑战.
- 对于研究生物分子而言,NMR具有独特的优势,但敏感性可能是有限的.
研究的目的:
- 研究19F动态核极化 (DNP) 魔术角度旋转 (MAS) NMR在HIV-1 CA组件中增强信号灵敏性的实用性.
- 探索DNP增强的F MAS NMR在获取远程结构信息方面的潜力.
- 系统地优化DNP参数以最大化信号增强.
主要方法:
- 19F动态核极化 (DNP) 魔力旋转角度 (MAS) 核磁共振光谱在14.1 T.
- 在20kHz以上的MAS频率获取2DF-13HETCOR频谱.
- 对DNP增强剂的系统定量,可变化二基度,MAS频率,温度和微波功率.
主要成果:
- 在HIV-1 CA组合的F DNP MAS光谱中实现了多达100倍的信号增强.
- 观察到的绝对灵敏度比为12-29,相当于H信号.
- 记录了2D F-C HETCOR光谱,揭示了长距离的分子内和分子间相关性.
- 在不同的实验条件下提供了DNP增强因子的系统数据.
结论:
- 用DNP增强的F MAS NMR为HIV-1 CA组件提供了显著的灵敏度改善.
- 这种技术为蛋白质结构的确定提供了独特的长距离限制.
- 这种方法对各种大型生物分子系统的结构特征非常有希望.
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