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关于单旋阿尔法螺旋的稳定性:单旋与多旋变形问题
James P Snyder1, Ami S Lakdawala, Michael J Kelso
1Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA. snyder@euch4e.chem.emory.edu
Journal of the American Chemical Society
|January 16, 2003
概括
这项研究挑战了循环的单个α螺旋模型. 形态分析揭示了多个快速相互转换的结构,而不是单一的螺旋,从平均的NMR数据.
科学领域:
- 协调化学 协调化学
- 计算化学是一种计算化学.
- 生物物理化学 生物物理化学
背景情况:
- (Palladium) 的复合可以诱导特定的形状.
- 之前的研究表明,基于2DNMR和模拟化,为[Pd(en) ((peptide) ]2+提供单个α螺旋.
研究的目的:
- 重新评估轮化五 [Pd(en) ((peptide) ]2+ 的溶液构型.
- 为了调查从平均NMR数据中假设单个形状的假设.
主要方法:
- 对Pd2+离子的AMBER*参数的开发.
- 使用分子动力学模拟进行广泛的构造性搜索.
- 将平均的2DNMR数据分解成多种形状.
主要成果:
- [Pd () ]2+复合体存在于八种不同的形状的平衡中.
- 没有一个被识别的形状代表了正规的α-helix.
- 一个轻微的形状 (3%) 显示结构上的相似性与一个alpha-helix.
结论:
- 对于[Pd(en) ((peptide) ]2+的平均NMR数据的单个构造假设是不正确的.
- 符合性解卷对于准确解释NMR光谱至关重要.
- 帕拉介导的循环形成了一个动态的结构组合.
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