title: Rhenium-labeled somatostatin analog RC-160. 1H NMR and computer modeling conformational analysis.
abstract: The solution conformations of RC-160, cyclic D-Phe1-Cys2-Tyr3-D-Trp4-Lys5-Val6-Cys7+ ++-Trp8-NH2, an analog of the tumor antiproliferatory neuropeptide somatostatin, and RC-160 labeled with rhenium (Re-RC-160), have been determined by using two-dimensional 1H NMR spectroscopy (600 MHz) and restrained molecular dynamics simulations. Re-RC-160 yields the same average solution conformation as does the apo form with an antiparallel beta-sheet fold and a type II' beta-turn centered at D-Trp4-Lys5. These results indicate that the spatial topography of the side chains essential for somatostatin receptor binding is maintained in Re-RC-160.
authors.affiliation: Jefferson Cancer Institute, Department of Pharmacology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107.
authors.forename: J M
authors.initials: JM
authors.lastname: Varnum
authors.forename: M L
authors.initials: ML
authors.lastname: Thakur
authors.forename: A V
authors.initials: AV
authors.lastname: Schally
authors.forename: S
authors.initials: S
authors.lastname: Jansen
authors.forename: K H
authors.initials: KH
authors.lastname: Mayo
mesh_terms: D000595:Amino Acid Sequence; D000970:Antineoplastic Agents / Q000737:chemistry*; D003198:Computer Simulation; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008969:Molecular Sequence Data; D012211:Rhenium / Q000737:chemistry*; D013004:Somatostatin / Q000031:analogs & derivatives* / Q000737:chemistry
chemical_list: D000970:Antineoplastic Agents; C051458:vapreotide; D013004:Somatostatin; D012211:Rhenium