作为传统抗生素有力的候选者,抗菌肽是先天免疫体系中的重要组成成分.抗菌肽从起初的接触至随后稳定地吸附到细菌CC的质膜之上,是抗菌肽发挥其抗菌功能的关键初始事件.为揭示这一尚未明了的过程,文中使用分子动力学模拟方法,通过构建抗菌肽HP(2-20)与POPE脂双层的体系,模拟了HP(2-20)与POPE脂膜间的非特异相互作用.结果表明:抗菌肽的N端最先与脂膜接触,随后抗菌肽将维持一种倾斜的姿态,经历一个旋动插入脂膜的过程;同时,抗菌肽将束缚膜上与其邻近的磷脂分子的运动,导致膜的不均匀性,增强脂膜磷脂分子的无序波动,为其它自由的抗菌肽分子更深的插入提供了机会.
As one of the most likely substitutes for conventional antibiotics, antimicrobial peptides (AMPs) are ancient players in innate immunity. In the antimicrobial action of AMPs, an initial key event is that AMPs firstly contact with and then closely adhere to the bacterial membrane. In order to reveal this unknown process, a molecu- lar dynamic (MD) simulation is performed to examine the nonspecific interaction of AMP HP(2-20) with the cell membrane, which is modeled by a POPE bilayer. The results show that the N-terminal of the peptide firstly contacts with the membrane, and then, companying with a rotation movement, the peptide slowly inclines toward and slightly inserts into the membrane; at the same time, the AMP limits the movements of the lipids adjacent to the peptide, which induces the membrane to become non-uniform and enhances the irregular fluctuation of the lipids, so that other peptides may find their chances of deeply inserting into the membrane.