胺和胺的相互作用:对蛋白质稳定性的影响
Robert W Newberry1, Brett VanVeller, Ilia A Guzei
1Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
Journal of the American Chemical Society
|May 14, 2013
概括
蛋白质骨干胺碳酸通过n→π*相互作用稳定结构. 提奥胺的加入增强了这种效果,这表明了一种稳定蛋白质结构的方法.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 计算化学计算化学
背景情况:
- 蛋白质中相邻的脊柱胺基对结构稳定性至关重要.
- 建议碳-碳相互作用在这种稳定性中发挥作用.
研究的目的:
- 研究相邻的骨干胺基之间的碳基-碳基相互作用的性质和能量贡献.
- 为了比较这些相互作用在oxoamides与thioamides中的强度.
- 为了确定这些相互作用是否更好地被描述为轨道或双极-双极相互作用.
主要方法:
- 结合实验和计算方法.
- 量子化学计算以确定相互作用能量和轨道相互作用.
- 对n→π*捐赠者-接受者相互作用的分析.
主要成果:
- 氨基碳基团通过n→π*的捐赠者-受体相互作用与至少0.27kcal/mol的能量结合在一起.
- 与oxoamides相比,thioamides中的n→π*相互作用是3倍强的.
- 这种差异归因于轨道重叠的增加和胺基的能量差异的减少.
- 碳烯相互作用比双极-双极相互作用更准确地被建模为轨道相互作用.
结论:
- n→π* 相互作用对蛋白质骨架的结构稳定性有显著的贡献.
- 在蛋白质骨干中加入胺胺可以增强结构稳定性.
- 轨道相互作用可以更准确地描述蛋白质中的碳-碳联结.
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