Sensitized photomodification of DNA with binary systems of oligonucleotide conjugates. III. Double-quantum sensitization
Dobrikov, M.I.; Gaĭdamakov, S.A.; Shishkin, G.V.; Vlasov, V.V.
Bioorganicheskaia Khimiia 24(11): 831-838
1998
ISSN/ISBN: 0132-3423 PMID: 10079940 Document Number: 492928
Site-specific modification of single-stranded DNA by oligonucleotide derivatives of p-azido-O-(4-aminobutyl)tetrafluorobenzaldoxime sensitized by an oligonucleotide derivative of pyrenylethylamine was studied. Upon irradiation with the long-wave UV light (365-390 nm) of a DNA target-oligonucleotide reagent complementary complex, a considerable increase in the rate of sensitized photomodification at the G11 residue of the target relative to the direct photomodification was observed owing to the singlet-single energy transfer from the sensitizer onto the photoreagent. Upon simultaneous irradiation of the complex with UV and visible light in the region of the triplet-triplet absorption of pyrene (360-580 nm), an additional increase in the modification rate and a change in its site-direction (from the G11 to T13 residue) occurred through the two-photon triplet-triplet sensitization. The total extent of the structure photomodification amounted to 80%.