title: [Mechanism of AT base pairs recognition by molecules of dye "Hoechst 33258"].
abstract: Experimental studies are reported on the binding of the dye "Hoechst 33 258" to DNA and synthetic polynucleotides. A stereochemical model of binding of the dye to DNA is proposed. According to the model, the molecules of the dye are located in the minor groove of DNA, each covering 4 base pairs. The benzimidazole backbone of the dye tends to form a helix isogeometric to that of DNA in the B form. The specifisity of "Hoechst 33 258" binding to At pairs involves hydrogen bonding of two NH-groups of benzimidazole rings and CH3N+H group of the piperazine ring to O2 oxygenes of thymines and N3 nitrogens of adenines facing the minor groove of the DNA double helix.
mesh_terms: D000225:Adenine; D001482:Base Composition; D001562:Benzimidazoles; D006690:Bisbenzimidazole; D055598:Chemical Phenomena; D002621:Chemistry; D004247:DNA; D006860:Hydrogen Bonding; D008433:Mathematics; D008958:Models, Molecular; D008968:Molecular Conformation; D009690:Nucleic Acid Conformation; D013053:Spectrophotometry; D013941:Thymine
chemical_list: D001562:Benzimidazoles; D004247:DNA; D000225:Adenine; D006690:Bisbenzimidazole; D013941:Thymine
vernacular_title: Mekhanizm "uznavaniia" AT-par v DNK molekulami krasitelia "Hoechst 33258".