title: Copper-mediated DNA photocleavage by a tetrapyridoacridine (tpac) ligand.
abstract: We have focused our interest on the tetrapyridoacridine ligand tetrapyrido[3,2-a:2',3'-c:3'',2''-h: 2''',3'''-j]acridine (tpac), as a model system for the preparation of novel copper-based artificial nucleases. The complex of copper(II)-tpac cleaves supercoiled pUC18 plasmid DNA in an oxidative manner by photoactivation with visible light, exhibiting maximum cleaving efficiency at 1:2 metal-ligand stoichiometric ratio. We propose an interaction of the copper-tpac complex with DNA through both major and minor grooves and a photocleavage mechanism via the formation of hydroxyl radicals and singlet oxygen or singlet oxygen-like species.
authors.affiliation: Departamento de Química Inorgánica, Universidad de Valencia, 46100-Burjassot, Valencia, Spain.
authors.lastname: Marta González-Alvarez
authors.forename: María-Selma
authors.initials: MS
authors.lastname: Arias
authors.forename: María-José
authors.initials: MJ
authors.lastname: Fernández
authors.forename: Lourdes
authors.initials: L
authors.lastname: Gude
authors.forename: Antonio
authors.initials: A
authors.lastname: Lorente
authors.forename: Gloria
authors.initials: G
authors.lastname: Alzuet
authors.forename: Joaquín
authors.initials: J
authors.lastname: Borrás
mesh_terms: D000166:Acridines / Q000737:chemistry*; D003300:Copper / Q000737:chemistry* / Q000378:metabolism; D004247:DNA / Q000378:metabolism* / Q000528:radiation effects*; D003851:Deoxyribonucleases / Q000378:metabolism*; D008024:Ligands; D008027:Light; D008958:Models, Molecular; D015394:Molecular Structure; D010618:Phenanthrolines / Q000737:chemistry*; D010777:Photochemistry; D026082:Singlet Oxygen / Q000737:chemistry
chemical_list: D000166:Acridines; D008024:Ligands; D010618:Phenanthrolines; C529854:tetrapyridoacridine; D026082:Singlet Oxygen; D003300:Copper; D004247:DNA; D003851:Deoxyribonucleases