An unlikely DNA cleaving agent: A photo-active trinuclear Cu(II) complex based on hexaazatriphenylene.

An unlikely DNA cleaving agent: A photo-active trinuclear Cu(II) complex based on hexaazatriphenylene.
J Inorg Biochem. 2016 Dec 15;168:55-66
Authors: Williams DE, Fischer CM, Kassai M, Gude L, Fernández MJ, Lorente A, Grant KB
Abstract
This paper describes the synthesis of a trinuclear Cu(II) complex (4) containing a central 1,4,5,8,9,12-hexaazatriphenylene-hexacarboxylate (hat) core (3). Low, micromolar concentrations of the negatively charged parent ligand 3 and the neutral trinuclear complex 4 were found to photocleave negatively charged pUC19 plasmid DNA with high efficiency at neutral pH (350nm, 50min, 22°C). The interactions of complex 4 with double-helical DNA were studied in detail. Scavenger and colorimetric assays pointed to the formation of Cu(I), superoxide anion radicals, hydrogen peroxide, and hydroxyl radicals during photocleavage reactions. UV-visible absorption, circular dichroism, DNA thermal denaturation, and fluorescence data suggested that the Cu(II) complex contacts double-stranded DNA in an external fashion. The persistent association of ligand 3 and complex 4 with Na(I) and/or other cations in aqueous solution might facilitate electrostatic DNA interactions.
PMID: 28013065 [PubMed - as supplied by publisher]

Source: Journal of Inorganic Biochemistry - December 14, 2016 Category: Biochemistry Authors: Williams DE, Fischer CM, Kassai M, Gude L, Fernández MJ, Lorente A, Grant KB Tags: J Inorg Biochem Source Type: research