Title
Effect of conformation of the Arylamine-DNA adduct on the sensitivity of [Ru(phen)2(dppz)]2 + complex
Author
T. Nandhini, V.G. Vaidyanathan, B.U. Nair
Year
2016
Journal
Inorganic Chemistry Communications
Abstract
DNA damage by endogenous/exogenous chemicals and ionizing radiation results in the formation of abasic sites, alkylation products, oxidative lesions and covalent-DNA adducts. The covalent DNA adducts adopt different conformations that might lead to various types of mutations. In the present study, we investigated the interaction of different Ru(II) polypyridyl complex, [Ru(phen)2(dppz)]2 + (phen: 1,10-phenanthroline; dppz: dipyrido[3,2-a:2′,3′-c]phenazine) with oligonucleotide sequences containing either [N-(2′-deoxyguanosin-8-yl)-2-aminofluorene] (AF-dG) or [N-(2′-deoxyguanosin-8-yl)-2-acetylaminofluorene] (AAF-dG) adduct. The modification of the oligonucleotides with the arylamines was characterized by UV–visible and MALDI-TOF spectroscopy. The results of thermal denaturation studies of oligonucleotide with Ru(II) complex indicate that Ru(II) complex stabilize the arylamine adducts better than control oligonucleotide. The integrated luminescence intensity of the Ru(II) complex was increased two-fold in AAF-dG adduct compared to control while a reverse trend was observed with AF-dG adduct. The addition of quencher enhanced the luminescence ratio between AF-modified and control duplex by 1.5 fold compared to 3.6 to 6-fold in AAF-dG adduct. The results from this study demonstrate the role of conformational heterogeneity of the arylamine-dG adduct in the binding of the Ru(II) complex and also provides us insight on the development of new probes.
Instrument
J-815
Keywords
Circular dichroism, Coordination chemistry, Stereochemistry, Inorganic chemistry, Materials, Biochemistry