title: [Bent dsDNA with defined geometric characteristics in terms of complexes of bridged oligonucleotides].
abstract: An opportunity of designing nontypical double-stranded DNA structures containing nonnatural inserts in a regular nucleotide DNA sequence has been investigated. The looped nucleotide inserts on the basis of adenylates and thymidilates, and nonnucleotide inserts on the basis of phosphodiesters of diethyleneglycol, 1,10-decanediol, and 3-hydroxy-2-hudroxymethyltetrahydrofuran were introduced into the backbone of a 32-mer native DNA duplex. These inserts formed the internal loops in the modified double-stranded DNA fragments which were shown to lead to bending of the linear duplex structure by 16 to 83 degrees. The dependencies of the bend angle of dsDNA on the composition and the length of the looped regions were determined. It was established that the bend of the irregular region of dsDNA depended on the electrostatic interaction of the phosphate residues. The tension in the complex structure could be reduced by the introduction of additional nucleotide units opposite the loop, which led to some relaxation of the bent helix. The resulting parameters of the bend values were shown to be in a good agreement with the published data obtained by NMR spectroscopy. It was demonstrated that the variation of the nature or the length of the insert allowed one to regulate the level of the local perturbation of the duplex structure and, thereby, influence both the bend level of the double helix and the destabilization of the modified complex.
authors.affiliation: Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, pr. Lavrent' eva 8, Novosibirsk, 630090 Russia.
authors.forename: O A
authors.initials: OA
authors.lastname: Vinogradova
authors.forename: E V
authors.initials: EV
authors.lastname: Eremeeva
authors.forename: A A
authors.initials: AA
authors.lastname: Lomzov
authors.forename: I A
authors.initials: IA
authors.lastname: Pyshnaia
authors.forename: D V
authors.initials: DV
authors.lastname: Pyshnyĭ
mesh_terms: D004247:DNA / Q000138:chemical synthesis / Q000737:chemistry*; D004591:Electrophoresis, Polyacrylamide Gel; D005026:Ethylene Glycols / Q000737:chemistry; D005233:Fatty Alcohols / Q000737:chemistry; D005663:Furans / Q000737:chemistry; D009690:Nucleic Acid Conformation; D009691:Nucleic Acid Denaturation; D009692:Nucleic Acid Heteroduplexes / Q000737:chemistry; D009841:Oligonucleotides / Q000737:chemistry*; D010755:Organophosphates / Q000737:chemistry
chemical_list: D005026:Ethylene Glycols; D005233:Fatty Alcohols; D005663:Furans; D009692:Nucleic Acid Heteroduplexes; D009841:Oligonucleotides; D010755:Organophosphates; C018674:tetrahydrofuran; C118975:1,10-decanediol; C013484:diethylene glycol; D004247:DNA