对-π,-π和硫-π相互作用的比较分析以及对SAM依赖的甲基转移酶的相关性
Katherine I Albanese1, Andrew Leaver-Fay2, Joseph W Treacy3
1Department of Chemistry, CB 3290, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States.
Journal of the American Chemical Society
|February 2, 2022
概括
由于极化性和溶解效应,硫-π相互作用最强,超过-π相互作用. 这会影响生物系统中的辅助因子循环.
科学领域:
- 生物物理化学
- 计算化学
- 结构生物学
背景情况:
- 非共价相互作用对于生物系统中的分子识别至关重要.
- 含硫的功能组在生物化学过程中起着至关重要的作用.
- 了解涉及硫的相互作用是酶功能和药物设计的关键.
研究的目的:
- 量化和比较硫-π,-π和-π的相互作用.
- 研究影响这些非共价相互作用强度的因素.
- 分析蛋白质结构中这些相互作用的流行程度和重要性,特别是S- 腺甲 (SAM) 和S- 腺homocysteine (SAH).
主要方法:
- 在β-hairpin模型系统中测量相互作用能量.
- 对相互作用机制进行详细分析的计算化学方法.
- 分析蛋白质数据库 (PDB) 以研究酶中的辅因子-蛋白质相互作用.
主要成果:
- 在研究的相互作用中,硫-π相互作用被发现是最强烈的.
- 与-π相互作用相比,极化性和溶解效应对-π相互作用的强度有显著的贡献.
- 在蛋白质中,虽然SAM和SAH都与芳香残留物相互作用,但SAM表现出SAH无法实现的独特的甲基-π相互作用.
结论:
- 硫-π 相互作用的强度受电子和溶解因子的影响.
- 在SAM和SAH之间的相互作用形状的差异,特别是SAH中的子-π相互作用的丧失,可能会促进辅因子的循环.
- 这些发现为酶催化和辅因子动态的分子基础提供了洞察力.
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