自相一致的3J合的卡普勒斯参数化取决于聚酸侧链扭矩 chi1
1Institut für Biophysikalische Chemie, Johann Wolfgang Goethe-Universität, Biozentrum N230, Marie-Curie-Strasse 9, D-60439 Frankfurt am Main, Germany.
Journal of the American Chemical Society
|July 19, 2001
概括
这项研究通过自相一致的3J合分析对氨基酸侧链的Karplus参数进行校准. 该方法完善了蛋白质结构的确定,并有助于在不依赖X射线坐标的情况下进行立体特定的分配.
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:
- 卡普勒斯参数在经验上将3J合常数与氨基酸侧链中的二面角联系起来.
- 准确的Karplus参数对于使用NMR数据来确定蛋白质结构至关重要.
研究的目的:
- 为了校准卡普勒斯对氨基酸侧链的参数,使用一种新的自相一致的3J合分析.
- 开发一种独立于X射线坐标的蛋白质结构确定和立体特异赋值方法.
主要方法:
- 同时优化6组卡普勒斯系数的最小平方,用于15N,13C标记蛋白中的6种3J合类型.
- 应用基本和增量组件合概念来考虑替代效应.
- 使用重组Desulfovibrio vulgaris flavodoxin的示例,分析了749个实验合常量.
主要成果:
- 衍生氨基酸拓特定的Karplus参数适用于其他蛋白质.
- 与以前的方法相比,通过与X射线扭转角度的交叉验证证明了更好的准确性.
- 获得了扭角度和局部角移动性参数,有助于蛋白质结构的确定.
结论:
- 自相一致的3J合分析为卡普勒斯参数校准提供了一个强大的方法,独立于晶体结构.
- 衍生的参数增强了蛋白质结构的确定,并使化学转移的自动立体特异性赋值成为可能.
- 核磁共振和X射线数据之间的差异突出显示了潜在的晶体包装效应和形状平衡.
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