在H2O中对胺-胺和胺-碳化合物相互作用进行原子对原子剖析的实验
Xian Cheng1, Irina A Shkel1, Kevin O'Connor1
1Program in Biophysics and ‡Departments of Biochemistry and §Chemistry University of Wisconsin-Madison , Madison, Wisconsin 53706, United States.
Journal of the American Chemical Society
|July 6, 2017
概括
这项研究使用度和可溶性量化了水中的胺相互作用. 它揭示了氨基酸,尿素和碳化合物之间的有利和不利相互作用,对于理解蛋白质折叠和水性过程至关重要.
科学领域:
- 生物物理化学
- 化学物理
- 分子相互作用
背景情况:
- 对水中的胺相互作用的定量理解对于蛋白质折叠和水性过程至关重要.
- 与计算模拟进行比较需要对这些相互作用进行准确的实验数据.
研究的目的:
- 量化水中的胺相互作用,包括与各种原子中心的尿素和基化尿素.
- 在水溶液中确定胺-芳香碳化合物相互作用.
- 为预测和解释生物和化学系统中的胺和碳化合物效应提供基础.
主要方法:
- 利用度测量测量水中的尿素和氨酸相互作用.
- 使用可溶性测量来量化胺-芳香碳化合物相互作用.
- 分析了与水中的特定原子中心 (sp2O,sp2N,sp3C,sp2C) 的相互作用强度.
主要成果:
- 胺sp2O与尿素和甲的相互作用是有利的,但与基尿素的相互作用是不利的,随着化而恶化.
- 观察到有利的氨基 sp2O-氨基 sp2N (键) 和 sp2O-芳香 sp2C (π-π*) 相互作用.
- 不良的氨基酸sp2O-sp3C相互作用与良好的尿素-sp3C和尿素-氨基酸sp2N相互作用形成对比,随着化而增加.
结论:
- 该研究提供了水中的胺,尿素和碳化合物的定量相互作用强度.
- 这些发现可以预测和解释生物聚合物和水性过程中的化物和碳化合物部分相互作用.
- 结果可以与模拟进行比较,并确定蛋白质折叠中埋藏的表面积.
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