title: Microscopic visualization of alamethicin incorporation into model membrane monolayers.
abstract: Lipid interactions and cooperative assembly properties are fundamental determinants for the action of antimicrobial membrane-active peptides. Here we analyze the interactions and aggregation properties of alamethicin, an antimicrobial pore-forming peptide, with films formed at the air/water interface. Surface-area/pressure isotherms, Brewster angle microscopy, and fluorescence-confocal microscopy provided detailed information on the morphologies and structural properties of the peptide and its effect on the film components. The pressure-area analysis and microscopy experiments facilitated unprecedented visualization of the structural consequences of alamethicin association at the air/water interface, with pure phospholipid films, and within mixed phospholipid/polydiacetylene (PDA) films. The analysis exposed the kinetic features and the interplay between the peptide aggregates and film constituents. In particular, the results demonstrate the use of phospholipid/PDA film assemblies for studying membrane-peptide association and interactions within two-dimensional films.
authors.affiliation: Ilse Katz Center for Nano- and Mesoscience and Technology, Department of Chemistry, and Department of Biotechnology Engineering, Ben Gurion University of the Negev, Beer-Sheva 84105, Israel.
authors.forename: Roman
authors.initials: R
authors.lastname: Volinsky
authors.forename: Sofiya
authors.initials: S
authors.lastname: Kolusheva
authors.forename: Amir
authors.initials: A
authors.lastname: Berman
authors.forename: Raz
authors.initials: R
authors.lastname: Jelinek
mesh_terms: D000114:Acetylene / Q000031:analogs & derivatives / Q000737:chemistry; D000388:Air; D000408:Alamethicin / Q000737:chemistry*; D008567:Membranes, Artificial; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D008956:Models, Chemical; D010316:Particle Size; D010743:Phospholipids / Q000737:chemistry; D000078789:Polyacetylene Polymer; D011108:Polymers / Q000737:chemistry; D053279:Polyynes; D013499:Surface Properties; D014867:Water / Q000737:chemistry
chemical_list: D008567:Membranes, Artificial; D010743:Phospholipids; D000078789:Polyacetylene Polymer; D011108:Polymers; D014867:Water; D053279:Polyynes; D000408:Alamethicin; C082361:polydiacetylene; D000114:Acetylene