title: Membrane topologies of the PGLa antimicrobial peptide and a transmembrane anchor sequence by Dynamic Nuclear Polarization/solid-state NMR spectroscopy.
abstract: Dynamic Nuclear Polarization (DNP) has been introduced to overcome the sensitivity limitations of nuclear magnetic resonance (NMR) spectroscopy also of supported lipid bilayers. When investigated by solid-state NMR techniques the approach typically involves doping the samples with biradicals and their investigation at cryo-temperatures. Here we investigated the effects of temperature and membrane hydration on the topology of amphipathic and hydrophobic membrane polypeptides. Although the antimicrobial PGLa peptide in dimyristoyl phospholipids is particularly sensitive to topological alterations, the DNP conditions represent well its membrane alignment also found in bacterial lipids at ambient temperature. With a novel membrane-anchored biradical and purpose-built hardware a 17-fold enhancement in NMR signal intensity is obtained by DNP which is one of the best obtained for a truly static matrix-free system. Furthermore, a membrane anchor sequence encompassing 19 hydrophobic amino acid residues was investigated. Although at cryotemperatures the transmembrane domain adjusts it membrane tilt angle by about 10 degrees, the temperature dependence of two-dimensional separated field spectra show that freezing the motions can have beneficial effects for the structural analysis of this sequence.
authors.affiliation: University of Strasbourg/CNRS, UMR7177, Chemistry Institute, 67070 Strasbourg, France.
authors.forename: Evgeniy Sergeevich
authors.initials: ES
authors.lastname: Salnikov
authors.affiliation: University of Strasbourg/CNRS, UMR7177, Chemistry Institute, 67070 Strasbourg, France.
authors.forename: Christopher
authors.initials: C
authors.lastname: Aisenbrey
authors.affiliation: Bruker BioSpin, 34, rue de l'Industrie, 67166 Wissembourg, France.
authors.forename: Fabien
authors.initials: F
authors.lastname: Aussenac
authors.affiliation: Aix-Marseille University, Institut de Chimie Radicalaire, UMR 7273, Faculté des Sciences, 13397 Marseille, Cédex 20, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Ouari
authors.affiliation: University of Strasbourg/CNRS, UMR7177, Chemistry Institute, 67070 Strasbourg, France.|Bruker BioSpin, Silberstreifen, 76287 Rheinstetten, Germany.
authors.forename: Hiba
authors.initials: H
authors.lastname: Sarrouj
authors.affiliation: Bruker BioSpin, Silberstreifen, 76287 Rheinstetten, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Reiter
authors.affiliation: Aix-Marseille University, Institut de Chimie Radicalaire, UMR 7273, Faculté des Sciences, 13397 Marseille, Cédex 20, France.
authors.forename: Paul
authors.initials: P
authors.lastname: Tordo
authors.affiliation: Bruker BioSpin, Silberstreifen, 76287 Rheinstetten, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Engelke
authors.affiliation: University of Strasbourg/CNRS, UMR7177, Chemistry Institute, 67070 Strasbourg, France.
authors.forename: Burkhard
authors.initials: B
authors.lastname: Bechinger
mesh_terms: D000595:Amino Acid Sequence; D000890:Anti-Infective Agents / Q000737:chemistry*; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry*; D003080:Cold Temperature; D004134:Dimyristoylphosphatidylcholine / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D008051:Lipid Bilayers / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000295:instrumentation / Q000379:methods*; D010713:Phosphatidylcholines / Q000737:chemistry*; D010715:Phosphatidylglycerols / Q000737:chemistry
chemical_list: D000890:Anti-Infective Agents; D023181:Antimicrobial Cationic Peptides; D008051:Lipid Bilayers; D010713:Phosphatidylcholines; D010715:Phosphatidylglycerols; C045866:peptide-Gly-Leu-amide; C002773:dimyristoylphosphatidylglycerol; C028694:1-palmitoyl-2-oleoylphosphatidylcholine; D004134:Dimyristoylphosphatidylcholine