title: Two-dimensional ordered beta-sheet lipopeptide monolayers.
abstract: A series of amphiphilic lipopeptides, ALPs, consisting of an alternating hydrophilic and hydrophobic amino acid residue sequence coupled to a phospholipid tail, was designed to form supramolecular assemblies composed of beta-sheet monolayers decorated by lipid tails at the air-water interface. A straightforward synthetic approach based on solid-phase synthesis, followed by an efficient purification protocol was used to prepare the lipid-peptide conjugates. Structural insight into the organization of monolayers was provided by surface pressure versus area isotherms, circular dichroism, Fourier transform infrared spectroscopy, and Brewster angle microscopy. In situ grazing-incidence X-ray diffraction (GIXD) revealed that lipopeptides six to eight amino acids in length form a new type of 2D self-organized monolayers that exhibit beta-sheet ribbons segregated by lipid tails. The conclusions drawn from the experimental findings were supported by a representative model based on molecular dynamics simulations of amphiphilic lipopeptides at the vacuum-water interface.
authors.affiliation: Contribution from the Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands.
authors.forename: Silvia
authors.initials: S
authors.lastname: Cavalli
authors.forename: Jan-Willem
authors.initials: JW
authors.lastname: Handgraaf
authors.forename: Emily E
authors.initials: EE
authors.lastname: Tellers
authors.forename: Daniela C
authors.initials: DC
authors.lastname: Popescu
authors.forename: Mark
authors.initials: M
authors.lastname: Overhand
authors.forename: Kristian
authors.initials: K
authors.lastname: Kjaer
authors.forename: Vladimir
authors.initials: V
authors.lastname: Vaiser
authors.forename: Nico A J M
authors.initials: NA
authors.lastname: Sommerdijk
authors.forename: Hanna
authors.initials: H
authors.lastname: Rapaport
authors.forename: Alexander
authors.initials: A
authors.lastname: Kros
mesh_terms: D000388:Air; D000595:Amino Acid Sequence; D002942:Circular Dichroism; D003198:Computer Simulation; D057927:Hydrophobic and Hydrophilic Interactions; D008055:Lipids / Q000737:chemistry*; D008074:Lipoproteins / Q000138:chemical synthesis*; D008567:Membranes, Artificial; D008956:Models, Chemical; D008969:Molecular Sequence Data; D017433:Protein Structure, Secondary; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D013816:Thermodynamics; D014867:Water / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: D008055:Lipids; D008074:Lipoproteins; D008567:Membranes, Artificial; D014867:Water