title: Low temperature structures of dCpG-proflavine. Conformational and hydration effects.
abstract: The structure of the complex of dCpG with proflavine was determined using x-ray data taken at -130 degrees C (low temperature) and at -2 degrees C (cold temperature) and compared with the structure of the complex determined previously at room temperature (Shieh, H. S., H. M. Berman, M. Dabrow, and S. Neidle. 1980. Nucleic Acids Res. 8:85-97). Low temperature was refined with 5,125 reflections between 8.0 and 0.93 A, Anisotropically modeled temperature factors were used for DNA/drug atoms and isotropic ones for water oxygens to R factor of 12.2% in P2(1)2(1)2; a = 32.853, b = 21.760, c = 13.296 A. Cold temperature was refined isotropically with 2,846 reflections 8.0-0.89 A to R = 15.1% in P2(1)2(1)2; a = 32.867, b = 22.356, c = 13.461 A. Both structures are very similar to the room temperature one, though some important differences were observed: one guanine sugar moiety is disordered and additional water molecules have been located that give rise to infinite polyhedral hydration networks.
authors: Department of Chemistry, Rutgers, State University of New Jersey, New Brunswick 08903.
authors: B
authors: B
authors: Schneider
authors: S L
authors: SL
authors: Ginell
authors: H M
authors: HM
authors: Berman
mesh_terms: D055592:Biophysical Phenomena; D001703:Biophysics; D003080:Cold Temperature; D003845:Deoxycytosine Nucleotides / Q000737:chemistry*; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D015394:Molecular Structure; D011370:Proflavine / Q000737:chemistry*; D014867:Water; D014961:X-Ray Diffraction
chemical_list: D003845:Deoxycytosine Nucleotides; D014867:Water; C037781:deoxycytidylyl-(3'-5')-deoxyguanosine; D011370:Proflavine; D003849:Deoxyguanosine