title: Transfer on hydrophobic substrates and AFM imaging of membrane proteins reconstituted in planar lipid bilayers.
abstract: The lipid-layer technique allows reconstituting transmembrane proteins at a high density in microns size planar membranes and suspended to a lipid monolayer at the air/water interface. In this paper, we transferred these membranes onto two hydrophobic substrates for further structural analysis of reconstituted proteins by Atomic Force Microscopy (AFM). We used a mica sheet covered by a lipid monolayer or a sheet of highly oriented pyrolytic graphite (HOPG) to trap the lipid monolayer at the interface and the suspended membranes. In both cases, we succeeded in the transfer of large membrane patches containing densely packed or 2D-crystallized proteins. As a proof of concept, we transferred and imaged the soluble Shiga toxin bound to its lipid ligand and the ATP-binding cassette (ABC) transporter BmrA reconstituted into a planar bilayer. AFM imaging with a lateral resolution in the nanometer range was achieved. Potential applications of this technique in structural biology and nanobiotechnology are discussed.
authors.affiliation: Centre de Biochimie Structurale, CNRS UMR 5048, INSERM U554, UM1, UM2, Montpellier, France.
authors.forename: Bastien
authors.initials: B
authors.lastname: Seantier
authors.forename: Manuela
authors.initials: M
authors.lastname: Dezi
authors.forename: Francesca
authors.initials: F
authors.lastname: Gubellini
authors.forename: Alexandre
authors.initials: A
authors.lastname: Berquand
authors.forename: Cédric
authors.initials: C
authors.lastname: Godefroy
authors.forename: Patrice
authors.initials: P
authors.lastname: Dosset
authors.forename: Daniel
authors.initials: D
authors.lastname: Lévy
authors.forename: Pierre-Emmanuel
authors.initials: PE
authors.lastname: Milhiet
mesh_terms: D008051:Lipid Bilayers / Q000737:chemistry*; D008565:Membrane Proteins / Q000737:chemistry*; D018625:Microscopy, Atomic Force / Q000379:methods*
chemical_list: D008051:Lipid Bilayers; D008565:Membrane Proteins