建模CH3SOH-芳香复合物,以探测蛋白质中的硫酸氨酸-芳香相互作用
Esam A Orabi1,2, Ann M English1
1Center for Research in Molecular Modeling (CERMM), Quebec Network for Research on Protein Function, Engineering, and Applications (PROTEO), and Department of Chemistry and Biochemistry, Concordia University, 7141 Sherbrooke Street West, Montreal, Quebec H4B 1R6, Canada. ann.english@concordia.ca.
Physical chemistry chemical physics : PCCP
|September 25, 2025
概括
囊硫酸 (CysOH) 与芳香残留物的相互作用是抗氧化酶和氧化还原信号的关键. 量子力学计算揭示了蛋白质如何稳定CysOH,影响其反应性和生物作用.
科学领域:
- 生物化学和分子生物学
- 计算化学的计算化学
- 化学物理 化学物理
背景情况:
- 囊硫酸 (CysOH) 是抗氧化酶催化和氧化还原信号的关键中间体.
- 蛋白质环境,特别是芳香残留物,调节了CysOH的反应性和稳定性.
- 了解这些相互作用对于破译氧化应激机制和酶功能至关重要.
研究的目的:
- 使用计算方法来描述CysOH和各种芳香氨基酸侧链之间的相互作用.
- 研究这些相互作用对气相和水相环境中的CysOH稳定性和反应性的影响.
- 提供关于蛋白质结构在CysOH形成和稳定中的作用的见解.
主要方法:
- 在模型复合体上进行了广泛的量子力学计算 (MP2 (全) / 6-311++G (d,p)).
- 使用了氨酸,氨酸,氨酸/氨酸和氨酸/氨酸的侧链模型.
- 进行了分子动力学 (MD) 模拟,以研究水复合物的行为,并对CH3SOH.优化的潜在模型进行了模拟.
主要成果:
- 气相复合体显示出显著的结合能 (-5到-25 kcal mol-1),氧化中心根据H-键捐赠和电离潜力而变化.
- 在水溶液中,CysOH复合物表现出优选的结合几何形状,自由能量范围从-0.6到- 5 kcal mol-1 .
- CysOH复合物在气相中通常比它们的CysH对应物更稳定,但在水中不那么稳定,有着显著的例外,如酸盐复合物.
结论:
- 芳香残留物在稳定CysOH方面发挥着重要作用,影响其反应性和生物功能.
- 该研究提供了有关蛋白质系统的CysOH-芳香相互作用的详细分子层面的理解.
- 这些发现有助于更广泛地了解生物系统中的氧化还原调节,氧化应激和酶机制.
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