title: Does a 2----5 beta-turn structure exist in enkephalins? Study of a fully protected Leu-enkephalin in organic solution by 17O-NMR.
abstract: The 17O chemical shifts of the Gly-2 and Gly-3 oxygens of a fully protected Leu-enkephalin were measured to be identical in acetone solution. This allows the conclusion that neither of these peptide oxygens is hydrogen bonded and that no specific 2----5 beta-turn structure exists to an appreciable extent.
authors.affiliation: Institut de Chimie Organique, Université de Lausanne, Switzerland.
authors.forename: E
authors.initials: E
authors.lastname: Moret
authors.forename: I P
authors.initials: IP
authors.lastname: Gerothanassis
authors.forename: R N
authors.initials: RN
authors.lastname: Hunston
authors.forename: J
authors.initials: J
authors.lastname: Lauterwein
mesh_terms: D055598:Chemical Phenomena; D002621:Chemistry; D004743:Enkephalin, Leucine; D005998:Glycine; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D010103:Oxygen Isotopes; D011487:Protein Conformation
chemical_list: D010103:Oxygen Isotopes; D004743:Enkephalin, Leucine; D005998:Glycine