本科生毕业论文（设计）
题 目抗菌肽段FK-13与膜相互作用的分子动力学模拟研究
姓专
名 业
年级、班级 系、部(院) 指导教师姓名 专业技术职务
2017年6月10日
目 录
摘 要 ............................................................................................................................... 1 英文摘要 ............................................................................................................................... 2 引 言 ............................................................................................................................... 3 正 文 ............................................................................................................................... 4 1实验平台概述 .................................................................................................................... 4 1.1 MD simulation简介 .................................................................................................... 4 1.2 力场与分子模拟软件的选择 .................................................................................... 5 1.2.1经验立场简述 ...................................................................................................... 5 1.2.2常用的分子模拟软件 .......................................................................................... 6 2 实验设计 ........................................................................................................................... 8 2.1模拟对象的选择 ......................................................................................................... 8 2.2 膜平衡的模拟 ............................................................................................................ 8 2.3 肽-膜体系的模拟 ....................................................................................................... 9 3 实验结果与分析 ............................................................................................................. 11 3.1 MD simulation收敛性 .............................................................................................. 11 3.2 抗菌肽段 LL-37 与POPC 、POPG的作用 ........................................................ 12 3.2.1 肽-膜间氢键形成 .............................................................................................. 12 3.3抗菌肽段的组成特点 ............................................................................................... 13 3.3.1 LL-37抗菌肽段FK-13蛋白质回旋半径变化 ................................................ 13 结 论 ............................................................................................................................. 15 参考文献 ............................................................................................................................. 16 综 述 ............................................................................................................................. 19
致 谢 ............................................................................................................................. 21
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摘 要
抗菌肽是一类小的宿主防御蛋白，能保护动物、植物等多细胞机体免于感染。LL-37是Cathelicidin家族中唯一的存在于人体中的抗菌肽，它能发挥抗菌、抗病毒、抗肿瘤以及免疫调节等方面的重要的作用。尽管对LL-37已经开展了较为广泛的研究，但是有关LL-37发挥抗菌活性的分子机制和作用过程有待于进一步研究。因此，研究抗菌肽LL-37与细胞膜的相互作用对于认识LL-37的细胞毒性机理以及了解其抗菌机制有重要的意义。课题用的是分子动力学模拟方法，研究抗菌肽LL-37的核心抗菌肽段FK-13与细菌细胞膜和哺乳动物细胞膜的作用情况。选用GROMOACS软件包，GROMOS 96 53A力场和充分含水模型进行常规分子动力学模拟，用POPG和 POPC分别模拟哺乳动物细胞膜和细菌细胞膜。通过模拟研究来探索LL-37的抗菌机理，从分子水平进一步揭示不同的膜环境对LL-37抗菌肽段活性的影响。
关键词：免疫调节；抗菌肽；LL-37；分子动力学模拟
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Abstract
Antimicrobial peptides are a small class of host defense proteins. It can protect plants, animals and other multicellular organisms from infection. LL-37 is the only Cathelicidin antimicrobial peptide in the human body,which is very important in antibacterial, anti-virus,anti-tumor and immune regulation and so on. Although LL-37 has been studied, the molecular mechanism and process of LL-37 play an active role in the process of antibacterial activity need to be further studied. Studying on the interaction of LL-37 and cell membrane for the understanding of the cellular toxicity mechanism of LL-37 and its antibacterial mechanism is important. The molecular dynamics simulation method was used to investigate the role of the core antimicrobial peptide FK-13 of antibacterial peptide LL-37 in bacterial cell membrane and mammalian cell membrane. GROMOACS software package, GROMOS96 53A6 force field and full water cut model were used to perform the conventional molecular dynamics simulation, and POPG and POPC were used to simulate the mammalian cell membrane and bacterial cell membrane respectively. The antibacterial mechanism of LL-37 was investigated by simulation, and the effects of different membrane environments on the activity of LL-37 antibacterial peptides were further revealed at the molecular level.
Key words:Immunoregulation; Antimicrobial Peptide; LL-37; Molecular Dynamics Simulation
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抗菌肽段FK-13与膜相互作用的分子动力学模拟研究毕业论文
