title: Photochemical modulation of DNA conformation by organic dications.
abstract: A group of azobenzene derivatives containing two quaternary ammonium groups with various intercharge distances between them was synthesised and used to control photochemically the conformation of genomic DNA by switching the distance between cationic ammonium groups in the dications. It was found that isomerisation of either dication from the trans form to cis resulted in an increase in the dication's efficiency for DNA compaction; this is associated with a decrease in intercharge distance between ammonium groups and leads to a better match of the binder's cationic groups to adjacent phosphate groups of DNA. Ammonium dications have several important advantages over the photosensitive surfactant type of diazobenzene reported earlier: they can be used at significantly lower (>100-fold) concentrations than photosensitive surfactants, and DNA conformation control can be performed over a broader concentration range of dications. The influence of intercharge distance in photosensitive dications on photo-induced DNA binding discrimination is discussed, and the molecular mechanism is proposed.
authors: Graduate School of Environmental Studies, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Japan. zinchenko@urban.env.nagoya-u.ac.jp
authors: Anatoly A
authors: AA
authors: Zinchenko
authors: Mao
authors: M
authors: Tanahashi
authors: Shizuaki
authors: S
authors: Murata
mesh_terms: D001391:Azo Compounds / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D001435:Bacteriophages / Q000235:genetics; D002412:Cations / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D004279:DNA, Viral / Q000737:chemistry / Q000187:drug effects* / Q000235:genetics; D008958:Models, Molecular; D009690:Nucleic Acid Conformation / Q000187:drug effects*; D010636:Phenols / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D010777:Photochemistry; D017319:Photosensitizing Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D013329:Structure-Activity Relationship
chemical_list: D001391:Azo Compounds; D002412:Cations; D004279:DNA, Viral; D010636:Phenols; D017319:Photosensitizing Agents