Does oxidative damage enhance or hinder antimicrobial peptide insertion into model bacterial lipid monolayers?

A number of antimicrobial agents work, at least in part, by interacting with the lipid layers of microbial cells, the composition of which differs in significant ways from that of mammalian cells. For instance, the antibacterial peptide protegrin is known to interact preferentially with bacterial membranes, which contain large amounts of anionic lipids, such as phosphoglycerol, PG, lipids, rather than mammalian cell membranes which are richer in phosphocholine, PC, lipids. The lipids layers of both microbial and mammalian cells are subject to continuous oxidative attack. In this proposal we wish to explore how the presence of oxidized lipids within model bacterial lipid monolayers changes the extend and nature of the interaction with protegrin. The results will lead to a better understanding of how antimicrobial peptides interact with more realistic models of bacterial membranes.

若干抗菌剂（antimicrobial agents）的作用机制至少部分在于与微生物细胞的脂质层相互作用，而微生物细胞脂质层的组成与哺乳动物细胞存在显著差异。例如，抗菌肽（antibacterial peptide）protegrin已知优先与细菌膜相互作用，后者含有大量阴离子脂质（anionic lipids），如磷酸甘油（phosphoglycerol，PG），而非富含磷酸胆碱（phosphocholine，PC）的哺乳动物细胞膜。微生物和哺乳动物细胞的脂质层均持续遭受氧化攻击。本研究计划旨在探究模型细菌脂质单分子层中氧化脂质的存在如何改变其与protegrin相互作用的程度及性质。研究结果将有助于更深入地理解抗菌肽与更接近真实情况的细菌膜模型之间的相互作用机制。