Title: | "Membrane defects enhance the interaction of antimicrobial peptides, aurein 1.2 versus caerin 1.1" |
Author(s): | Fernandez DI; Sani MA; Miles AJ; Wallace BA; Separovic F; |
Address: | "School of Chemistry, University of Melbourne, VIC 3010, Australia" |
DOI: | 10.1016/j.bbamem.2013.03.010 |
ISSN/ISBN: | 0006-3002 (Print) 0006-3002 (Linking) |
Abstract: | "The membrane interactions of the antimicrobial peptides aurein 1.2 and caerin 1.1 were observed by (31)P and (2)H solid-state NMR and circular dichroism spectroscopy. Both peptides were relatively unstructured in water. In the presence of dimyristoylphosphatidylcholine (DMPC) and mixed DMPC and dimyristoylphosphatidylglycerol (DMPG) vesicles, both peptides displayed a considerable increase in helical content with the shorter aurein peptide having a higher alpha-helix content in both lipid systems. In fluid phase DMPC vesicles, the peptides displayed differential interactions: aurein 1.2 interacted primarily with the bilayer surface, while the longer caerin 1.1 was able to penetrate into the bilayer interior. Both peptides displayed a preferential interaction with the DMPG component in DMPC/DMPG bilayers, with aurein 1.2 limited to interaction with the surface and caerin 1.1 able to penetrate into the bilayer and promote formation of a mixture of lipid phases or domains. In gel phase DMPC vesicles, aurein 1.2 disrupted the bilayer apparently through a carpet mechanism, while no additional interaction was seen with caerin 1.1. Although a lamellar bilayer was retained with the mixed DMPC/DMPG vesicles below the phase transition, both caerin 1.1 and aurein 1.2 promoted disruption of the bilayer and formation of an isotropic phase. The peptide interaction was enhanced relative to the fluid phase and was likely driven by co-existence of membrane defects. This study thus demonstrates that the effects of the lipid phase and domains need to be considered when studying membrane interactions of antimicrobial peptides" |
Keywords: | Anti-Infective Agents/*pharmacology Antimicrobial Cationic Peptides/*metabolism Cell Membrane/drug effects/*pathology Circular Dichroism Lipid Bilayers/*metabolism Magnetic Resonance Spectroscopy Peptide Fragments/chemistry/*metabolism Phase Transition Se; |
Notes: | "MedlineFernandez, David I Sani, Marc-Antoine Miles, Andrew J Wallace, B A Separovic, Frances eng Biotechnology and Biological Sciences Research Council/United Kingdom Research Support, Non-U.S. Gov't Netherlands 2013/03/20 Biochim Biophys Acta. 2013 Aug; 1828(8):1863-72. doi: 10.1016/j.bbamem.2013.03.010. Epub 2013 Mar 15" |