Mechanism of action of the peptide antibiotic nisin in liposomes and cytochrome c oxidase-containing proteoliposomes

作者：F H Gao, Tjakko Abee, Wilhelmus N. Konings · 发表于：Applied and Environmental Microbiology · 年份：1991 · DOI：10.1128/aem.57.8.2164-2170.1991 · 被引用次数：208 · 研究领域：Antimicrobial Peptides and Activities、Lipid Membrane Structure and Behavior、Biochemical and Structural Characterization

The interaction of the peptide antibiotic nisin with liposomes has been studied. The effect of this interaction was analyzed on the membrane potential (inside negative) and the pH gradient (inside alkaline) in liposomes made from Escherichia coli phosphatidylethanolamine and egg phosphatidylcholine (9:1, wt/wt). The membrane potential and pH gradient were generated by artificial ion gradients or by the oxidation of ascorbate, N,N,N',N'-tetramethyl-p-phenylenediamine, and cytochrome c by the beef heart cytochrome c oxidase incorporated in the liposomal membranes. Nisin dissipated the membrane potential and the pH gradient in both types of liposomes and inhibited oxygen consumption by cytochrome c oxidase in proteoliposomes. The dissipation of the proton motive force in proteoliposomes was only to a minor extent due to a decrease of the oxidase activity by nisin. The results in these model systems show that a membrane potential and/or a pH gradient across the membrane enhances the activity of nisin. Nisin incorporates into the membrane and makes the membrane permeable for ions. As a result, both the membrane potential and pH gradient are dissipated. The activity of nisin was found to be influenced by the phospholipid composition of the liposomal membrane.