Ultraviolet irradiation of nucleic acids: formation, purification, and solution conformational analyses of the cis-syn and trans-syn photodimers of UpU.
Uridylyl(3'-5')uridine (UpU) is subjected to aqueous acetone photosensitized radiation with sunlamps. These irradiation conditions form only cyclobutane-type photodimers. Purification of a specific configurational photodimer is accomplished by using C-18 reverse-phase high-performance liquid chromatography. Multinuclear NMR analysis is used to analyze photoproduct formation and to determine conformational features of these photodimers. Four photodimers are identified, with the cis-syn isomer predominant. The cis-syn and trans-syn photodimers of UpU exhibit markedly different furanose and exocyclic bond conformations. A comparison of the properties of the cis-syn dimers of UpU with those of dTpdT reveal many similar conformational features but also some that are different.
Rycyna
R E
RE
Biophysics Department, Roswell Park Memorial Institute, Buffalo, New York 14263.
Alderfer
J L
JL
D015226:Dinucleoside Phosphates; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D009690:Nucleic Acid Conformation; D010777:Photochemistry; D014466:Ultraviolet Rays; D014500:Uracil Nucleotides / Q000528:radiation effects*; D014529:Uridine / Q000031:analogs & derivatives* / Q000528:radiation effects; D014542:Uridine Monophosphate / Q000031:analogs & derivatives / Q000528:radiation effects*
D015226:Dinucleoside Phosphates; D014500:Uracil Nucleotides; C026519:uridine monophosphate-uridine; D014542:Uridine Monophosphate; D014529:Uridine