The present study examined the structure and dynamics of the most active and thermostable carbonic anhydrase, SazCA, probed using molecular dynamics simulations. The molecular system was described by widely used biological force‐fields (AMBER, CHARMM22, CHARMM36, and OPLS‐AA) in conjunction with TIP3P water model. The comparison of molecular dynamics simulation results suggested AMBER to be a suitable choice to describe the structure and dynamics of SazCA. In addition to this, we also addressed the effect of temperature on the stability of SazCA. We performed molecular dynamics simulations at 313, 333, 353, 373, and 393 K to study the relationship between thermostability and flexibility in SazCA. The amino acid residues VAL98, ASN99, GLY100, LYS101, GLU145, and HIS207 were identified as the most flexible residues from root‐mean‐square fluctuations. The salt bridge analysis showed that ion‐pairs ASP113‐LYS81, ASP115‐LYS81, ASP115‐LYS114, GLU144‐LYS143, and GLU144‐LYS206, were responsible for the compromised thermal stability of SazCA.

中文翻译：

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分子动力学模拟确定了 SazCA 中热稳定性受损的区域

本研究检查了使用分子动力学模拟探测的最具活性和热稳定性的碳酸酐酶 SazCA 的结构和动力学。分子系统由广泛使用的生物力场（AMBER、CHARMM22、CHARMM36 和 OPLS-AA）结合 TIP3P 水模型进行描述。分子动力学模拟结果的比较表明 AMBER 是描述 SazCA 结构和动力学的合适选择。除此之外，我们还解决了温度对 SazCA 稳定性的影响。我们在 313、333、353、373 和 393 K 下进行了分子动力学模拟，以研究 SazCA 中热稳定性和柔韧性之间的关系。氨基酸残基 VAL98、ASN99、GLY100、LYS101、GLU145 和 HIS207 被鉴定为均方根波动中最灵活的残基。