title: Synthesis and characterization of β-peptide helices as transmembrane domains in lipid model membranes.
abstract: Aggregation, orientation and dynamics of transmembrane helices are of relevance for protein function and transmembrane signaling. To explore the interactions of transmembrane helices and the interdependence of peptide structure and lipid composition of the membranes, β-peptides were explored as model transmembrane domains. Various hydrophobic β-peptide sequences were synthesized by solid phase peptide synthesis. Conformational analyses of β-peptide helices were performed in organic solvents (methanol and 2,2,2-trifluoroethanol) and in large unilamellar liposomes (dimyristoylphosphatidylcholine, dipalmitoylphosphatidylcholine and dioleoylphosphatidylcholine) indicating 12- and 14-helix conformations, depending on β3-amino acid sequences. The intrinsic tryptophan fluorescence of β3-homotryptophan units inserted in the center or near the end of the sequence was used to verify the membrane insertion of the β-peptides. A characteristic blue shift with peripheral β3-homotryptophan compared with β-peptides with central tryptophan served as indication for a transmembrane orientation of the β-peptides within the lipid bilayer. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.
authors: Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstraße 2, 37077, Göttingen, Germany.
authors: Denis M
authors: DM
authors: Pahlke
authors: Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstraße 2, 37077, Göttingen, Germany. udieder@gwdg.de.
authors: Ulf
authors: U
authors: Diederichsen
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine; D000595:Amino Acid Sequence; D004134:Dimyristoylphosphatidylcholine; D057927:Hydrophobic and Hydrophilic Interactions; D008051:Lipid Bilayers / Q000737:chemistry*; D000432:Methanol / Q000737:chemistry; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry; D010713:Phosphatidylcholines; D017433:Protein Structure, Secondary; D060327:Solid-Phase Synthesis Techniques; D012997:Solvents / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D014270:Trifluoroethanol / Q000737:chemistry; D014364:Tryptophan / Q000737:chemistry*; D053835:Unilamellar Liposomes / Q000737:chemistry*
chemical_list: D008051:Lipid Bilayers; D010455:Peptides; D010713:Phosphatidylcholines; D012997:Solvents; D053835:Unilamellar Liposomes; D015060:1,2-Dipalmitoylphosphatidylcholine; D014270:Trifluoroethanol; D014364:Tryptophan; C017251:1,2-oleoylphosphatidylcholine; D004134:Dimyristoylphosphatidylcholine; D000432:Methanol
keywords: circular dichroism; liposomes; transmembrane domain; tryptophan fluorescence; β-peptides