Ru(L)2(3-tppp)]2 + (L = bpy, phen) stabilizes two different forms of the human telomeric G-quadruplex DNA

Abstract

The binding properties of new complexes [Ru(L)2(3-tppp)]2+ (L=bpy, phen) towards two different forms of the human telomeric G-quadruplexes DNA have been investigated by UV–Vis spectroscopy, fluorescent indicator displacement (FID) assays, fluorescence resonance energy transfer (FRET) melting assays and molecular docking studies. The molecular docking studies indicated that both complexes interacted with 22AG with the stoichiometric ratio of 1:1, but the two complexes showed different G-quadruplexed DNA binding affinity. Complex 2 bound to the G-quadruplexes DNA more tightly than complex 1 did. Moreover, the FRET melting assay revealed that both complexes could be potential stabilizers for G-quadruplex architectures. These studies are useful not only for better understanding of the interaction between the target G-quadruplexes DNA and metal complexes but also valuable in defining the best strategy to prepare metal complexes as potential anticancer drugs.