title: Exploring the membrane mechanism of the bioactive peptaibol ampullosporin a using lipid monolayers and supported biomimetic membranes.
abstract: Ampullosporin A is an antimicrobial, neuroleptic peptaibol, the behavior of which was investigated in different membrane mimetic environments made of egg yolk L-α-phosphatidylcholine. In monolayers, the peptaibol adopted a mixed α/3(10)-helical structure with an in-plane orientation. The binding step was followed by the peptide insertion into the lipid monolayer core. The relevance of the inner lipid leaflet nature was studied by comparing ampullosporin binding on a hybrid bilayer, in which this leaflet was a rigid alkane layer, and on supported fluid lipid bilayers. The membrane binding was examined by surface plasmon resonance spectroscopy and the effect on lipid dynamics was explored using fluorescence recovery after photobleaching. In the absence of voltage and at low concentration, ampullosporin A substantially adsorbed onto lipid surfaces and its interaction with biomimetic models was strongly modified depending on the inner leaflet structure. At high concentration, ampullosporin A addition led to the lipid bilayers disruption.
authors.affiliation: UMR 6022 CNRS Génie Enzymatique et Cellulaire, Université de Technologie de Compiègne, BP 20529, 60205 Compiègne Cedex, France.
authors.forename: Marguerita
authors.initials: M
authors.lastname: Eid
authors.forename: Sonia
authors.initials: S
authors.lastname: Rippa
authors.forename: Sabine
authors.initials: S
authors.lastname: Castano
authors.forename: Bernard
authors.initials: B
authors.lastname: Desbat
authors.forename: Joël
authors.initials: J
authors.lastname: Chopineau
authors.forename: Claire
authors.initials: C
authors.lastname: Rossi
authors.forename: Laure
authors.initials: L
authors.lastname: Béven