title: Membrane lysis by gramicidin S visualized in red blood cells and giant vesicles.
abstract: The cationic amphiphilic antimicrobial peptide gramicidin S (GS) is an effective antibiotic. Its applicability is however restricted to topical infections due to its hemolytic activity. In this study, the process of GS induced hemolysis was investigated in detail for the first time. The morphological changes of red blood cells (RBCs) inflicted by GS were visualized and explained in terms of a physical model. The observed fast rupture events were further investigated with giant unilamellar vesicles (GUVs) as model systems for RBCs. Measurements of membrane fluctuations in GUVs revealed that the membrane surface tension was increased after incubation with GS. These findings are in agreement with the hypothesis that amphiphilic peptides induce membrane rupture by an increase in membrane tension.
authors.affiliation: Physics of Life Processes, Leiden Institute of Physics, Leiden University, Leiden, The Netherlands. semrau@physics.leidenuniv.nl
authors.forename: S
authors.initials: S
authors.lastname: Semrau
authors.forename: M W L
authors.initials: MW
authors.lastname: Monster
authors.forename: M
authors.initials: M
authors.lastname: van der Knaap
authors.forename: B I
authors.initials: BI
authors.lastname: Florea
authors.forename: T
authors.initials: T
authors.lastname: Schmidt
authors.forename: M
authors.initials: M
authors.lastname: Overhand
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004910:Erythrocyte Membrane / Q000187:drug effects*; D006096:Gramicidin / Q000494:pharmacology*; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D053835:Unilamellar Liposomes
chemical_list: D000900:Anti-Bacterial Agents; D053835:Unilamellar Liposomes; D006096:Gramicidin