title: N.m.r studies of internal mobility in a cyclic tetrapeptide.
abstract: The conformation of cyclo(D-Phe-D-Pro-Ala-Pro) is reported. Measurements of spin-lattice relaxation in the rotating frame indicate that this peptide is conformationally less mobile on the microsecond time scale than larger cyclic peptides previously studied. Libration of the Pro-Ala and Pro-Phe peptide bond planes is suggested as the source of the small exchange contributions to 1/T1p.
authors.forename: K D
authors.initials: KD
authors.lastname: Kopple
authors.forename: Y S
authors.initials: YS
authors.lastname: Wang
mesh_terms: D009682:Magnetic Resonance Spectroscopy; D009842:Oligopeptides / Q000032:analysis*; D010456:Peptides, Cyclic / Q000032:analysis*
chemical_list: D009842:Oligopeptides; D010456:Peptides, Cyclic