在溶液,玻璃和晶体状态下,烯维特里昂的动态
Josef Kapitán1, Vladimír Baumruk, Vladimír Kopecký
1Institute of Organic Chemistry and Biochemistry, Academy of Sciences, Flemingovo nam. 2, 16610, Prague 6, Czech Republic.
Journal of the American Chemical Society
|October 13, 2006
概括
拉曼光谱检测发现了proline.
科学领域:
- 频谱学是一种光谱学.
- 计算化学计算化学
- 生物物理学的生物物理.
背景情况:
- 氨酸是蛋白质结构和功能的关键氨基酸.
- 了解proline的结构灵活性是其生物作用的关键.
- 之前的研究已经探讨了proline的特性,但溶液中的详细分子动力学仍然难以捉摸.
研究的目的:
- 为了研究溶液中的L-和D-prolinezwitterions的分子运动和形状灵活性.
- 为了比较proline在溶液,玻璃和晶体状态中的行为.
- 为了阐明普林环和碳基团旋转之间的关系.
主要方法:
- 在H2O和D2O溶液中的普罗林的拉曼和拉曼光学活性光谱.
- 与玻璃性和晶体性普罗林的拉曼散射进行比较.
- 密度函数理论 (DFT) 用连续和显式溶剂模型进行计算.
- 用于动态平均计算的二维潜在能量表面的构建.
主要成果:
- 溶液和玻璃光谱显示了类似的带宽,表明了显著的内部分子运动.
- 在溶液和玻璃中存在两个同样拥挤的柔性适合体,与晶体中的单一,不那么柔性适合体形成鲜明对比.
- 氨酸环是与碳基团旋转强烈相关的,平均这些运动重现实验带宽.
- 分子环境通过与离子组的相互作用间接地影响了proline的疏水部分.
结论:
- 烯在溶液和玻璃中表现出显著的形状灵活性,具有两种不同的,同样拥挤的形式.
- 晶体普罗林在形状上受到限制,其灵活性降低.
- 环境的相互作用,特别是与离子组的相互作用,调节了proline的特性,可能会影响生物活动.
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