title: [Sensitized photomodification of DNA with binary systems of oligonucleotide conjugates. V. Effect of the structure of the target DNA. Quantitative photomodification].
abstract: A sensitized photomodification of several single-stranded target DNAs by binary systems of oligonucleotide conjugates complementary to the adjacent regions of DNA was performed. One of the conjugates contained a sensitizer (pyrene, anthracene, or 1,2-benzanthracene), and another conjugate contained a photoreagent 4-azidotetrafluorobenzalhydrazone. The sensitized photomodification is initiated by irradiation at 365-580 nm due to effective energy transfer from the excited sensitizer to the photoreagent in a complementary complex of the binary system with the target DNA where the sensitizer and photoreagent are brought sterically together. Conditions for the quantitative photomodification of a single-stranded DNA by the binary system of oligonucleotide conjugates were found. The maximum degree of photomodification depends on the number of guanosine residues in the (pG)n sequence of the target DNA at the modification site: at n = 1 the yield of covalent adducts was 62-68%, at n = 2, 75-82%, and at n = 4, 98-99%.
authors.affiliation: Novosibirsk Institute of Bioorganic Chemistry, Siberian Division, Russian Academy of Sciences, Russia.
authors.forename: M I
authors.initials: MI
authors.lastname: Dobrikov
authors.forename: S A
authors.initials: SA
authors.lastname: Gaĭdamakov
authors.forename: T I
authors.initials: TI
authors.lastname: Gaĭnutdinov
authors.forename: T M
authors.initials: TM
authors.lastname: Ivanova
authors.forename: V V
authors.initials: VV
authors.lastname: Vlasov
mesh_terms: D001483:Base Sequence; D004247:DNA / Q000737:chemistry / Q000528:radiation effects*; D004735:Energy Transfer; D010777:Photochemistry; D017319:Photosensitizing Agents / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet
chemical_list: D017319:Photosensitizing Agents; D004247:DNA