Interaction of an antimicrobial peptide from Lactobacillus gasseri supernatant with lipid bilayers mimicking the bacterial outer membrane

A short peptide, composed of 12 amino acids (EFVFVAHAVPVM), presenting a strongly hydrophobic character, was recently isolated from Lactobacillus gasseri supernatant (AMP12). This peptide has shown antimicrobial activity and may also bind the TLR4 receptor or lipopolysaccharides (LPS), which can result in blocking the activation of the inflammatory pathway. AMP12 was also hypothesized to penetrate into the cell given its small size and its character strongly hydrophobic. We are interested in the characterization of the interaction between AMP12 and lipid bilayers as mimics of the bacterial membrane. NR measurements can provide unique information on the mechanism of action of AMP12. We propose to characterize asymmetric lipid bilayers containing LPS from Escherichia Coli to investigate the location of AMP12 with respect to the bilayer.

近期从格氏乳杆菌（Lactobacillus gasseri）上清液中分离得到一种由12个氨基酸组成的短肽，其序列为EFVFVAHAVPVM，具有强疏水性，命名为AMP12。该肽段不仅展现出抗菌活性，还可结合Toll样受体4（TLR4）或脂多糖（LPS），进而阻断炎症通路的激活。鉴于其分子量较小且疏水性较强，AMP12被推测可穿透细胞。本研究聚焦于AMP12与模拟细菌细胞膜的脂质双分子层之间相互作用的表征，中子反射（NR）测量可为阐明AMP12的作用机制提供独特的关键信息。本研究拟构建含有大肠杆菌（Escherichia coli）脂多糖（LPS）的不对称脂质双分子层，以探究AMP12在双分子层中的具体定位。