精确的电子核距离从偏磁放松增强
Henry W Orton1, Gottfried Otting1
1Research School of Chemistry , Australian National University , Canberra , Australian Capital Territory 2601 , Australia.
Journal of the American Chemical Society
|May 24, 2018
概括
这项研究引入了一种使用兰坦化物进行准确,无校准的蛋白质距离测量的新方法,该方法是通过对磁放松增强剂 (PREs) 来进行的. 这种方法有效地减去非特异性影响,改善长期结构洞察力.
科学领域:
- 结构生物学
- 核磁共振 (NMR) 光谱学
- 生物物理
背景情况:
- 在1H NMR光谱中,偏磁放松增强 (PREs) 对于确定蛋白质中的长距离至关重要.
- 对于PREs的定量解释往往受到非特异性的分子间效应的阻碍.
- 在蛋白质结构研究中,准确的无校准距离测量仍然是一个挑战.
研究的目的:
- 开发一种使用PREs的准确,无校准距离测量方法.
- 克服非特异性分子间PREs所造成的限制.
- 为了提高定量分析,利用具有异性磁性易感性的兰坦化物.
主要方法:
- 使用具有异性磁性易感性的兰坦化物产生PREs.
- 在单个蛋白质样本中测量了对磁和对磁状态的放松率.
- 使用伪接触转移同时标记蛋白质与磁性和二磁性化物离子.
主要成果:
- 证明了来自异型兰坦酸的PREs能够准确地进行无校准距离测量.
- 通过计算核放松率的差异成功减去非特异性分子间PREs.
- 在使用埃尔的分子内PRE测量中获得了前所未有的准确性,产生距离预测<0.9 Å RMSD.
结论:
- 具有异性磁性易感性的兰化物为蛋白质中准确,无校准的距离测量提供了可靠的途径.
- 开发的方法有效地减轻非特异性分子间PRE,提高定量解释.
- 这种技术为结构生物学中精确的远距离测定提供了强大的工具.
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