title: Mechanisms of peptide-induced pore formation in lipid bilayers investigated by oriented 31P solid-state NMR spectroscopy.
abstract: There is a considerable interest in understanding the function of antimicrobial peptides (AMPs), but the details of their mode of action is not fully understood. This motivates extensive efforts in determining structural and mechanistic parameters for AMP's interaction with lipid membranes. In this study we show that oriented-sample (31)P solid-state NMR spectroscopy can be used to probe the membrane perturbations and disruption by AMPs. For two AMPs, alamethicin and novicidin, we observe that the majority of the lipids remain in a planar bilayer conformation but that a number of lipids are involved in the peptide anchoring. These lipids display reduced dynamics. Our study supports previous studies showing that alamethicin adopts a transmembrane arrangement without significant disturbance of the surrounding lipids, while novicidin forms toroidal pores at high concentrations leading to more extensive membrane disturbance.
authors.affiliation: Center for Insoluble Protein Structures (inSPIN), Department of Chemistry, University of Aarhus, Aarhus, Denmark.
authors.forename: Kresten
authors.initials: K
authors.lastname: Bertelsen
authors.forename: Jerzy
authors.initials: J
authors.lastname: Dorosz
authors.forename: Sara Krogh
authors.initials: SK
authors.lastname: Hansen
authors.forename: Niels Chr
authors.initials: NC
authors.lastname: Nielsen
authors.forename: Thomas
authors.initials: T
authors.lastname: Vosegaard
mesh_terms: D000408:Alamethicin / Q000737:chemistry*; D000890:Anti-Infective Agents / Q000737:chemistry*; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry*; D004134:Dimyristoylphosphatidylcholine / Q000737:chemistry; D008051:Lipid Bilayers / Q000737:chemistry*; D008956:Models, Chemical; D008968:Molecular Conformation; D019906:Nuclear Magnetic Resonance, Biomolecular
chemical_list: D000890:Anti-Infective Agents; D023181:Antimicrobial Cationic Peptides; D008051:Lipid Bilayers; C554278:novicidin; D000408:Alamethicin; D004134:Dimyristoylphosphatidylcholine