title: Synthesis of spin-labeled RNAs for long range distance measurements by peldor.
abstract: Site directed spin labeled RNA duplexes with different interspin distances were synthesized. The radical 2,2,5,5-tetramethyl-pyrrolin- 1-yloxyl-3-acetylene (TPA) was introduced during the solid-phase synthesis through a Sonogashira cross-coupling with 5-iodo-uridine. Tm and CD studies showed that the spin label does not to disturb significantly the A-form of these duplexes. 4-Pulse Electron Double Resonance (PELDOR) was then used to measure intramolecular spin-spin distances of 19.3, 33.0 and 40.9 A, which are in very good agreement with the calculated values of 17.6, 32.1 and 39.1 A, obtained from Molecular Dynamics (MD) simulations.
authors.affiliation: Institut für Organische Chemie und Chemische Biologie (OCCB), Johann Wolfgang Goethe-Universität, Frankfurt am Main, Germany.
authors.forename: Nelly
authors.initials: N
authors.lastname: Piton
authors.forename: Olav
authors.initials: O
authors.lastname: Schiemann
authors.forename: Yuguang
authors.initials: Y
authors.lastname: Mu
authors.forename: Gerhard
authors.initials: G
authors.lastname: Stock
authors.forename: Thomas
authors.initials: T
authors.lastname: Prisner
authors.forename: Joachim W
authors.initials: JW
authors.lastname: Engels
mesh_terms: D001671:Biochemistry / Q000379:methods; D002942:Circular Dichroism; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D004583:Electrons; D008024:Ligands; D008956:Models, Chemical; D008967:Molecular Biology / Q000379:methods; D008968:Molecular Conformation; D009690:Nucleic Acid Conformation; D012313:RNA / Q000737:chemistry*; D012984:Software; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013113:Spin Labels; D013696:Temperature
chemical_list: D008024:Ligands; D013113:Spin Labels; D012313:RNA