Berlin 2005 – wissenschaftliches Programm
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CPP: Chemische Physik und Polymerphysik
CPP 29: POSTER: Polymer physics
CPP 29.2: Poster
Dienstag, 8. März 2005, 16:30–18:30, Poster TU D
The Antibiotic Peptide KLA1 Induces Fluctuating Membrane Pores — •Dennis Kim1,2, Margitta Dathe3, Sergej Bezrukov4, Thomas Hauss5, Silvia Dante5, and Beate Klösgen2 — 1La Jolla Bioengineering Institute, La Jolla, USA — 2University of Southern Denmark, Odense, Denmark — 3Institute of Molecular Pharmacology, Berlin, Germany — 4NICHD, Bethesda MD, USA — 5Hahn-Meitner Institute, Berlin, Germany
Antimicrobial peptides constitute the first natural line of defense against pathogens in animals and plants. During the last decade, thousands of these AMPs have been isolated from their natural sources or designed de novo with the goal of creating another generation of antibiotics to counter increasingly resistant bacteria. The effect of a synthetic antimicrobial peptide, KLA1, on a lipid model bilayer was studied by a combination of methods including cryo-TEM, SANS, conductivity experiments, and micromechanical deformation studies by micropipet aspiration. Experiments were done on small unilamellar vesicles (SUVs), planar membrane stacks, black lipid membranes (BLMs), and giant unilamellar vesicles (GUVs). Results are presented and discussed with respect on different models for induction of membrane lysis. Our system seems to represent an example for the toroidal pore model that involves the spontaneous formation of transitory membrane holes. Such pores fluctuate, and their formation and stability are governed by local defect induced modulations of the elsehow continuous bending elastic properties of the membrane.