基于R9抗菌肽与非对称磷脂膜的相互作用分析抗菌肽浓度对磷脂膜穿透的影响

Effects of Peptide Concentrations on Membrane Penetration from the Interaction of R9 Peptides with Asymmetric Lipid Bilayer

了解穿膜肽与细胞膜的相互作用在生物医学中具有重要意义。本文我们用粗粒化分子动力学模拟的方法研究了R9抗菌肽与非对称细胞膜之间的相互作用,发现单个抗菌肽自发穿透磷脂膜十分困难,只有当抗菌肽的浓度达到一个阈值,非对称膜形成一个亲水性的环形孔,随后抗菌肽沿此孔道穿过磷脂膜。这是由于抗菌肽协同效应及其与磷脂膜之间静电相互作用增强所致。随着抗菌肽浓度的增加,抗菌肽穿过的个数也随之增加。该研究能够帮助理解抗菌肽穿透细胞膜的机制,并对药物设计和药物传递有一定的意义。

Understanding how cell-penetrating peptides interact with membrane is significant in biomedi-cine. In this article, we study the interactions between R9 peptides with asymmetric membranes by using coarse-grained molecular dynamics simulations. We find that it is very difficult for one peptide to cross over the lipid bilayer spontaneously. Only when the concentration of antibacterial peptide reaches a threshold can the asymmetric membrane form a hydrophilic circular pore, and the antibacterial peptide pass through the porous membrane along the pore channel, due to the synergistic effect of antimicrobial peptides and the enhancement of the electrostatic interaction between the antimicrobial peptides and the phospholipid membrane. With the increase of peptide concentration, the number of penetrating peptides also increases. Our research can better help to understand the mechanism of antimicrobial peptides penetrating the cell membrane and provide some help for the delivery of drugs.