title: Non-intercalative binding mode of bridged binuclear chiral Ru(II) complexes to native duplex DNA.
abstract: A pair of chiral binuclear ruthenium(II) complexes were prepared and their binding affinities towards double stranded native DNA were assessed by observing isotropic absorption, polarized light spectra - circular and linear dichroism (CD and LD), fluorescence quenching and DNA thermal denaturation. Upon binding to DNA, the complexes produced LD signals consisting of positive and negative signals in the absorption region, although they exhibited red shift and hypochromism in the absorption spectrum. These contrasting observations indicated that the binding modes of the complexes are largely deviated from classical intercalative binding. Groove binding of the complexes to DNA was found to be more likely than intercalative binding. The small increase of DNA melting temperature in the presence of the complexes indicated a predominance of DNA groove binding. The absence of "molecular light switch effect" further supported non-intercalative binding. The groove binding propensity of complexes was also supported by comparison of the resulting data with the [Ru(phen)(2)(dppz)](2+).
authors: Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, Buk-gu, Daegu-city, Republic of Korea.
authors: Nataraj
authors: N
authors: Chitrapriya
authors: Yoon Jung
authors: YJ
authors: Jang
authors: Seog K
authors: SK
authors: Kim
authors: Hyosun
authors: H
authors: Lee
mesh_terms: D001667:Binding, Competitive; D002942:Circular Dichroism; D056831:Coordination Complexes / Q000138:chemical synthesis / Q000737:chemistry*; D004247:DNA / Q000737:chemistry*; D004996:Ethidium / Q000737:chemistry; D007364:Intercalating Agents / Q000737:chemistry; D009690:Nucleic Acid Conformation; D012428:Ruthenium; D013050:Spectrometry, Fluorescence; D013237:Stereoisomerism; D044366:Transition Temperature
chemical_list: D056831:Coordination Complexes; D007364:Intercalating Agents; D012428:Ruthenium; D004247:DNA; C427203:calf thymus DNA; D004996:Ethidium