title: [Circular dichroism of DNA--dye complexes. II. Anisotropy of the long-wave circular dichroism effect and structure of the complex].
abstract: Anisotropy of torsional strength of the splitted electronic transition in the case of chromophore-chromophore interaction of dye molecules situated on the helical matrix was considered theoretically and as analytical expression for the value Rperpendicular/Rparallel was obtained. These theoretical results were compared with the experimental data obtained with DNA-proflavine, DNA-pyronine and DNA-acridine orange complexes oriented in multicappilar flow-cell. Studies of the optical effects (optical density and CD changes) due to orientation of these complexes showed that the acridine chromophores are not perpendicular with respect to the DNA axis (alpha D = 19--22 degrees). The DNA base pairs in complexes as assumed also are not perpendicular to the DNA axis, the inclination angle of their transition moments (for the band near 260 nm) being bigger than that of dye chromophores (24 degrees). These results indicate that under experimental conditions used by us no intercalation can be observed.
mesh_terms: D000166:Acridines; D055598:Chemical Phenomena; D002621:Chemistry; D002942:Circular Dichroism; D004247:DNA; D004269:DNA, Bacterial; D004214:Distamycins; D004926:Escherichia coli / Q000032:analysis; D009690:Nucleic Acid Conformation; D011370:Proflavine; D011754:Pyronine; D011758:Pyrroles; D013057:Spectrum Analysis; D014966:Xanthenes
chemical_list: D000166:Acridines; D004269:DNA, Bacterial; D004214:Distamycins; D011758:Pyrroles; D014966:Xanthenes; D004247:DNA; D011370:Proflavine; D011754:Pyronine
vernacular_title: Krugovoĭ dikhroizm kompleksov krasiteleĭ s DNK. II. Anizotropiia dlinnovolnovogo éffekta krugovogo dikhroizma i struktura kompleksa.