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Ubiquitin Chain Analysis by Parallel Reaction Monitoring
Published on: June 17, 2020
从 (3) J 合常量和残余双极合中得到的尿素脱的乌比奎和蛋白质G 的侧链形状
Navratna Vajpai1, Martin Gentner, Jie-Rong Huang
1Biozentrum, University of Basel, Klingelbergstrasse 50/70, 4056 Basel, Switzerland.
Journal of the American Chemical Society
|February 17, 2010
概括
这项研究引入了新的NMR方法,以精确测量未折叠蛋白质的侧链构造,揭示序列特异性相互作用并改进结构模型.
科学领域:
- 生物物理学的生物物理.
- 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
背景情况:
- 在未折叠的蛋白质中表征侧链形状是具有挑战性的,因为NMR中的共振分散性差.
- 关于无序状态中蛋白质侧链的动态和结构细节的信息有限.
研究的目的:
- 开发和验证优化的NMR方案,用于检测未折叠蛋白质中的标尺合和残余二极合 (RDC).
- 精确确定侧链 (chi () 1) 角度) 构造,并探索尿素变质蛋白中的序列特异相互作用.
主要方法:
- 优化了NMR脉冲序列,用于检测 (3) J ((HalphaHbeta), (3) J ((NHbeta), (3) J ((C'Hbeta) 的标量合和 (1) D ((CbetaHbeta) 的RDC.
- 适用于尿素脱的乌比奎和蛋白质G.
- 使用混合分层 chi(1) 旋转机模型解释合器.
主要成果:
- 检测最多6个 (3) J-合到 (1) H ((β),以高精度定义 chi ((1) 角度 (大多数残留物<2%).
- 从线圈平均值显著偏差的识别,表明序列和残留特异性相互作用,特别是对于氨酸和三氨酸.
- 测量 (1) D ((CbetaHbeta) RDC 与线圈模型之间的良好相关性,支持其作为第一个近似值的有效性.
结论:
- 开发的NMR方法使得在未折叠的蛋白质中严格表征侧链和脊柱形状.
- 序列特异性相互作用显著影响侧链形状,超出了简单的线圈模型.
- RDC数据可以在未折叠状态下完善本地骨干形态描述.
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