在异构化过程中,在二的两侧诱导金字塔化的内部和分子间相互作用:在明确的水中进行一项ab initio QM/MM分子动力学模拟研究
Yasushige Yonezawa1, Kazuto Nakata, Kota Sakakura
1Institute for Protein Research, Osaka University, 3-2 Yamada-oka, Suita, Osaka 565-0871, Japan. yasuyon33@protein.osaka-u.ac.jp
Journal of the American Chemical Society
|March 10, 2009
概括
在氨酸残留之前,键的cis-trans异构化对蛋白质折叠至关重要. 这项研究揭示了一种新的过渡状态机制,涉及金字塔构造和键延伸,澄清了异构化过程.
科学领域:
- 生物化学 生物化学
- 计算化学计算化学
- 分子生物学分子生物学
背景情况:
- 键的cis-trans异构化,特别是前面的proline,对于蛋白质的折叠和功能至关重要.
- 尽管进行了广泛的研究,但这种异构化的确切机制仍然不完全理解.
研究的目的:
- 为了阐明明明确水中的二的cis-trans异体化分子机制.
- 描述异构化过程的过渡状态和自由能景观.
主要方法:
- 分子动力学模拟利用一个结合的ab initio量子力学/实证分子力学潜力.
- 雨抽样方法来确定自由能源景观.
主要成果:
- 自由能源格局与现有的实验和理论数据保持一致.
- 确定了一个过渡状态,其中prolyl采用过渡的金字塔形状,C-N键扩展.
- 这些几何变化有助于在prolyl中从sp(2) 转向sp(3) 杂交,降低旋转障碍.
结论:
- 这项研究阐明了proline二酸的cis-trans异构化机制.
- 金字塔式体构造和C-N键延伸是过渡状态的关键特征.
- 和分子内相互作用影响不同金字塔形状的稳定性.
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