title: The structure of the membrane-binding 38 C-terminal residues from bovine PP3 determined by liquid- and solid-state NMR spectroscopy.
abstract: The secondary structure and membrane-associated conformation of a synthetic peptide corresponding to the putative membrane-binding C-terminal 38 residues of the bovine milk component PP3 was determined using 1H NMR in methanol, CD in methanol and SDS micelles, and 15N solid-state NMR in planar phospholipid bilayers. The solution NMR and CD spectra reveal that the PP3 peptide in methanol and SDS predominantly adopts an alpha-helical conformation extending over its entire length with a potential bend around residue 19. 15N solid-state NMR of two PP3 peptides 15N-labelled at the Gly7 and Ala32 positions, respectively, and dissolved in dimyristoylphosphatidylcholine/dimyristoylphosphatidylglycerol phospholipid bilayers shows that the peptide is associated to the membrane surface with the amphipathic helix axis oriented parallel to the bilayer surface.
authors.affiliation: Laboratory for Biomolecular NMR Spectroscopy, Department of Molecular and Structural Biology, Science Park, University of Aarhus, Denmark.
authors.forename: M
authors.initials: M
authors.lastname: Bak
authors.forename: M D
authors.initials: MD
authors.lastname: Sorensen
authors.forename: E S
authors.initials: ES
authors.lastname: Sorensen
authors.forename: L K
authors.initials: LK
authors.lastname: Rasmussen
authors.forename: O W
authors.initials: OW
authors.lastname: Sorensen
authors.forename: T E
authors.initials: TE
authors.lastname: Petersen
authors.forename: N C
authors.initials: NC
authors.lastname: Nielsen
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002364:Caseins / Q000737:chemistry* / Q000378:metabolism*; D002417:Cattle; D002462:Cell Membrane / Q000378:metabolism*; D002942:Circular Dichroism; D004134:Dimyristoylphosphatidylcholine / Q000378:metabolism; D006023:Glycoproteins / Q000737:chemistry* / Q000378:metabolism*; D006860:Hydrogen Bonding; D008051:Lipid Bilayers / Q000737:chemistry / Q000378:metabolism; D000432:Methanol / Q000378:metabolism; D008823:Micelles; D008958:Models, Molecular; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D010446:Peptide Fragments / Q000737:chemistry* / Q000378:metabolism*; D010715:Phosphatidylglycerols / Q000378:metabolism; D017433:Protein Structure, Secondary; D012967:Sodium Dodecyl Sulfate / Q000378:metabolism; D013816:Thermodynamics
chemical_list: D002364:Caseins; D006023:Glycoproteins; D008051:Lipid Bilayers; D008823:Micelles; C085522:PP3 protein, Bos taurus; D010446:Peptide Fragments; D010715:Phosphatidylglycerols; D012967:Sodium Dodecyl Sulfate; C002773:dimyristoylphosphatidylglycerol; D004134:Dimyristoylphosphatidylcholine; D000432:Methanol