title: [The nature of stabilization of the tandem DNA duplex pTGGAGCTG (pCAGC + (Phn-NH-(CH2)3-NH)pTCCA) based on the UV-, CD-, and two-dimensional NMR spectroscopy data].
abstract: Properties and three-dimensional structure of the tandem DNA duplex pTGGAGCTG.(pCAGC+(PhnL)pTCCA) in aqueous solution, where L is an amino linker and Phn is an N-(2-hydroxyethyl)phenazinium residue, were studied spectrophotometrically and by two-dimensional 1H NMR spectroscopy (COSY and NOESY). When a tandem complex involving a Phn residue-bearing oligonucleotide is formed, the dye aromatic system intercalates into the double helix at the nick site and takes part in two stacking interactions: a strong one (3.5-4 A) with the T5-A12 base pair of its own duplex moiety and a weak one (4-5 A) with the C4-G13 pair of the adjoining duplex (mainly with the C4 base). This arrangement of the dye residue, providing a cross-interaction of the phenazinium moiety with the base pairs of the adjacent duplex structures, results in the stabilization of the whole tandem complex.
authors.affiliation: Novosibirsk Institute of Bioorganic Chemistry, Siberian Division, Russian Academy of Sciences, Russia.
authors.forename: A Iu
authors.initials: AIu
authors.lastname: Denisov
authors.forename: D V
authors.initials: DV
authors.lastname: Pyshnyĭ
authors.forename: E M
authors.initials: EM
authors.lastname: Ivanova
mesh_terms: D004247:DNA / Q000737:chemistry*; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D010619:Phenazines; D013057:Spectrum Analysis
chemical_list: D010619:Phenazines; C076555:10-(2-hydroxyethyl)phenazine; D004247:DNA