title: Structure and membrane interactions of the antibiotic peptide dermadistinctin K by multidimensional solution and oriented 15N and 31P solid-state NMR spectroscopy.
abstract: DD K, a peptide first isolated from the skin secretion of the Phyllomedusa distincta frog, has been prepared by solid-phase chemical peptide synthesis and its conformation was studied in trifluoroethanol/water as well as in the presence of sodium dodecyl sulfate and dodecylphosphocholine micelles or small unilamellar vesicles. Multidimensional solution NMR spectroscopy indicates an alpha-helical conformation in membrane environments starting at residue 7 and extending to the C-terminal carboxyamide. Furthermore, DD K has been labeled with (15)N at a single alanine position that is located within the helical core region of the sequence. When reconstituted into oriented phosphatidylcholine membranes the resulting (15)N solid-state NMR spectrum shows a well-defined helix alignment parallel to the membrane surface in excellent agreement with the amphipathic character of DD K. Proton-decoupled (31)P solid-state NMR spectroscopy indicates that the peptide creates a high level of disorder at the level of the phospholipid headgroup suggesting that DD K partitions into the bilayer where it severely disrupts membrane packing.
authors.affiliation: Departamento de Química Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Rodrigo M
authors.initials: RM
authors.lastname: Verly
authors.forename: Cléria Mendonça
authors.initials: CM
authors.lastname: de Moraes
authors.forename: Jarbas M
authors.initials: JM
authors.lastname: Resende
authors.forename: Christopher
authors.initials: C
authors.lastname: Aisenbrey
authors.forename: Marcelo Porto
authors.initials: MP
authors.lastname: Bemquerer
authors.forename: Dorila
authors.initials: D
authors.lastname: Piló-Veloso
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Valente
authors.forename: Fábio C L
authors.initials: FC
authors.lastname: Almeida
authors.forename: Burkhard
authors.initials: B
authors.lastname: Bechinger
mesh_terms: D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry*; D001001:Anura; D002942:Circular Dichroism; D008051:Lipid Bilayers / Q000737:chemistry; D008823:Micelles; D008958:Models, Molecular; D009587:Nitrogen Isotopes; D019906:Nuclear Magnetic Resonance, Biomolecular; D010713:Phosphatidylcholines; D010759:Phosphorus Isotopes; D010767:Phosphorylcholine / Q000031:analogs & derivatives / Q000737:chemistry; D011487:Protein Conformation; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D014270:Trifluoroethanol / Q000737:chemistry; D053835:Unilamellar Liposomes / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D023181:Antimicrobial Cationic Peptides; D008051:Lipid Bilayers; D008823:Micelles; D009587:Nitrogen Isotopes; D010713:Phosphatidylcholines; D010759:Phosphorus Isotopes; D053835:Unilamellar Liposomes; C527843:dermadistinctin K, Phyllomedusa distincta; D014867:Water; D010767:Phosphorylcholine; D012967:Sodium Dodecyl Sulfate; C028810:dodecylphosphocholine; D014270:Trifluoroethanol; C028694:1-palmitoyl-2-oleoylphosphatidylcholine