Alkhatabi Heba A, Alhashmi Mohammad, Alkhatabi Hind Ali, Altayb Hisham N
Faculty of Applied Medical Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia.
Hematology Research Unit (HRU), King Fahd Medical Research Center, King Abdulaziz University, Jeddah 22254, Saudi Arabia.
Animals (Basel). 2025 Jan 28;15(3):381. doi: 10.3390/ani15030381.
Cytochrome c is a critical protein in energy metabolism, and its structural adaptations to different temperatures play a key role in enabling species like the wild () and the () to thrive in their respective cold and hot environments. This study investigates the structural, thermodynamic, and dynamic properties of cytochrome c at different temperatures. Thermal Titration Molecular Dynamics (TTMD) simulations, which involve analyzing protein behaviour across a range of temperatures, were carried out using GROMACS, with each simulation running for 100 nanoseconds, at 245 K, 280 K, 303 K, 308 K, and 320 K, to evaluate stability and flexibility. Structural alterations were indicated by an increase in root mean square deviations (RMSDs) to 0.4 nm at 320 K, as opposed to lower RMSD values (0.1-0.2 nm) at 245 K and 280 K. Root mean square fluctuation (RMSF) analyses revealed modest flexibility at 245 K and 280 K (0.1-0.2 nm) but considerable flexibility (0.3-0.4 nm) at 303 K and 320 K. Principal component analysis (PCA) found that the formational space was constrained at lower temperatures but expanded at higher temperatures. Entropy peaked at 280 K (13,816 J/mol) and then fell substantially at 320 K (451.765 J/mol), indicating diminished stability. These findings highlight cytochrome c adaptations for cold stability in and thermal resilience in , showing evolutionary strategies for harsh conditions.
细胞色素c是能量代谢中的一种关键蛋白质,其对不同温度的结构适应性在使诸如野生()和()等物种能够在各自的寒冷和炎热环境中繁衍生息方面发挥着关键作用。本研究调查了细胞色素c在不同温度下的结构、热力学和动力学性质。使用GROMACS进行了热滴定分子动力学(TTMD)模拟,该模拟涉及分析蛋白质在一系列温度下的行为,每个模拟在245 K、280 K、303 K、308 K和320 K下运行100纳秒,以评估稳定性和灵活性。结构变化表现为在320 K时均方根偏差(RMSD)增加到0.4 nm,而在245 K和280 K时RMSD值较低(0.1 - 0.2 nm)。均方根波动(RMSF)分析显示,在245 K和280 K时灵活性适中(0.1 - 0.2 nm),但在303 K和320 K时灵活性相当大(0.3 - 0.4 nm)。主成分分析(PCA)发现,构象空间在较低温度下受到限制,但在较高温度下扩大。熵在280 K时达到峰值(13,816 J/mol),然后在320 K时大幅下降(451.765 J/mol),表明稳定性降低。这些发现突出了细胞色素c在(物种名缺失)中对寒冷稳定性的适应性以及在(物种名缺失)中对热弹性的适应性,展示了针对恶劣条件的进化策略。