一个恒定的pH分子动力学和不同的pH对Sporosarcina pasteurii的尿酶结构的影响的实验研究
Yifei Zheng1,2, Lingling Wu1,2, Qiucai Zhang1,2
1School of Resources, Environment and Safety Engineering, University of South China, Zhengxiang, Hengyang, 421001, China.
Journal of molecular modeling
|May 19, 2025
概括
这项研究显示,在微生物诱导的碳酸沉 (MICP) 中,尿酶活性的最佳pH值为7-8. 极端的pH值会破坏尿酶的结构和功能,影响MICP在恶劣环境中的应用.
科学领域:
- 酶学 是一种酶学.
- 生物化学 生物化学
- 环境科学 环境科学
背景情况:
- 尿酸对于微生物诱导的碳酸沉 (MICP) 是至关重要的.
- 了解极端pH的尿酶稳定性对于MICP在矿井排水等具有挑战性的环境中的应用至关重要.
- 这项研究研究了Sporosarcina pasteurii尿酶在pH范围3-11的行为.
研究的目的:
- 为了确定pH值变化对Sporosarcina pasteurii尿酶的结构稳定性和催化活性的影响.
- 在MICP中确定尿酶功能的最佳pH条件.
- 为增强地质技术和环境修复中的MICP提供见解.
主要方法:
- 组合实验室实验测量尿酶活性通过导电性变化与恒定pH分子动力学 (CpHMD) 模拟.
- 在不同的pH条件下分析了尿酸酶α子单元 (PDB: 4CEU) 的结构稳定性 (RMSD),活性位点动态和质子化状态 (3-11).
- 使用GROMACS,CHARMM36力场,PCA和λ-动力学进行计算分析.
主要成果:
- 在pH7-8下观察到最佳的尿酶活性和结构稳定性,通过最小的RMSD和稳定的质子化状态得到证实.
- 极端的pH值条件 (3,4,11) 导致活动部位中断,电荷波动和催化功能受损.
- CpHMD模拟表明,尿酶α子单元在pH 7-8下保持结构完整性,这表明有可能重新组装.
结论:
- 该研究确立了pH7-8为Sporosarcina pasteurii尿酶活性和结构完整性的最佳值.
- 极端的pH值显著损害尿酶功能,限制其在恶劣环境中的应用.
- 这些发现为优化环境修复和地质工程中的MICP战略提供了关键数据.
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