2022年 06期

氯离子通道膜蛋白内部离子输运的动力学模拟

Dynamic Simulation of Ion Transport in Chloride Ion Channel Membrane Protein


摘要(Abstract):

为了方便、直观地研究氯离子通道膜蛋白内部氯离子输运过程的动力学性质,利用全原子分子动力学模拟方法对大肠杆菌氯离子通道膜蛋白的蛋白质-膜-水溶液系统进行能量最小化和平衡模拟,并对氯离子在通道中输运过程的受力进行拉伸分子动力学模拟计算。结果表明:平衡模拟约40 ns后,膜蛋白结构逐步达到热力学平衡态;通道内部中间结合位点氯离子与周围氨基酸相互作用最强,稳定性最好;氯离子输运过程中主要受到通道尺寸影响,通道宽处受力小,通道窄处受力大,其中靠近外部结合位点处通道最窄,氯离子所受拉力最大,约为300 pN。

关键词(KeyWords): 氯离子通道膜蛋白;分子动力学模拟;拉伸分子动力学;离子输运

基金项目(Foundation): 国家自然科学基金项目(11804121);; 湖北省大学生创新训练计划项目(S202011072069);; 江汉大学学生学术科技项目(2020zd056,2021yb138,2022zd043);江汉大学校级科研项目(2021yb026)

作者(Author): 于涛,胡雄飞,王哲,向泽雨,王鑫

DOI: 10.13349/j.cnki.jdxbn.20220919.002

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