title: Solution conformation of c-[Gln-Trp-Phe-Gly-Leu-Met], a NK-2 tachykinin antagonist.
abstract: The conformation of cyclo-[Gln-Trp-Phe-Gly-Leu-Met], a potent tachykinin antagonist selective for the NK-2 receptor, has been studied by 1H NMR spectroscopy in DMSO-d6 and in a DMSO-d6/H2O cryoprotective mixture in the temperature range 280-320 K. The NMR data cannot be interpreted on the basis of a single ordered conformation. An exhaustive search, based mainly on missing NOEs among skeleton protons, yields a description of the conformational state in solution consisting of a few interconverting structures that can explain all observed NMR parameters. The relative position of the side chains of key residues may be interpreted in terms of bioactive conformations.
authors.affiliation: Department of Chemistry, University of Naples Federico II, Naples, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Amodeo
authors.forename: P
authors.initials: P
authors.lastname: Rovero
authors.forename: G
authors.initials: G
authors.lastname: Saviano
authors.forename: P A
authors.initials: PA
authors.lastname: Temussi
mesh_terms: D000595:Amino Acid Sequence; D004121:Dimethyl Sulfoxide; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D010456:Peptides, Cyclic / Q000737:chemistry*; D011487:Protein Conformation; D018041:Receptors, Neurokinin-2 / Q000037:antagonists & inhibitors*; D012996:Solutions
chemical_list: D010456:Peptides, Cyclic; D018041:Receptors, Neurokinin-2; D012996:Solutions; C073361:cyclo(Gln-Trp-Phe-Gly-Leu-Met); D004121:Dimethyl Sulfoxide