Mechanisms and Products of Photosensitized Degradation of Nucleic Acids and Related Model Compounds

摘要: The mechanisms and products of photosensitized singlet oxygen oxidation nucleic acid model compounds have been investigated using kinetics analysis product isolation identification. A competitive is presented as a simple yet quantitative method for the determination role in homogeneous chemical reactions. This compared to other techniques that used past including solvent isotope effect quenchers variations substrate concentration. results experiments indicate photooxidation dGuo (2′-deoxyguanosine) at pH 7–10 buffered aqueous solution sensitized by Rose Bengal, Methylene Blue, Thionine or several dyes proceeds predominantly pathway requiring intermediate formation oxygen. In contrast, under same conditions flavin pterin derivatives pathways do not involve Most primary are very unstable consequently difficult, if impossible, isolate characterize. However, two now isolated correspond addition single molecule purine ring guanine with system still intact. Some formed 2′-deoxyguanosine appear be different than some reactions agreement kinetic proceed intermediacy If unique nature can firmly established it may possible detect vivo analysis.