0000000000651391
AUTHOR
M. J. Fernandez
showing 2 related works from this author
Copper-mediated DNA photocleavage by a tetrapyridoacridine (tpac) ligand.
2008
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.
Synthesis and copper-mediated nuclease activity of a tetracationic tris(2,2′-bipyridine) ligand
2009
Abstract We report herein the synthesis of a novel tetracationic tris(2,2′-bipyridine) ligand 4 . We show that this ligand metalated with copper(II), and in the presence of ascorbate as a reducing agent, strongly damages pUC18 plasmid DNA. Copper complex formation was demonstrated by ESI-MS (electrospray ionization-mass spectrum) at a 1:3 ligand to metal ratio. Binding of both 4 and its copper(II) complex to CT-DNA (calf thymus DNA) was characterized by viscosimetry, thermal denaturation and fluorescence-based competition assays. The viscosimetric data indicated that 4 and its copper(II) complex bind DNA through partial intercalation and thermal denaturation studies revealed a significant i…