Two-dimensional ordered beta-sheet lipopeptide monolayers.
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.
Cavalli
Silvia
S
Contribution from the Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands.
Handgraaf
Jan-Willem
JW
Tellers
Emily E
EE
Popescu
Daniela C
DC
Overhand
Mark
M
Kjaer
Kristian
K
Vaiser
Vladimir
V
Sommerdijk
Nico A J M
NA
Rapaport
Hanna
H
Kros
Alexander
A
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
D008055:Lipids; D008074:Lipoproteins; D008567:Membranes, Artificial; D014867:Water