G-quadruplex vs. duplex-DNA binding of nickel(II) and zinc(II) Schiff base complexes
- Authors: Bonsignore, R.; Terenzi, A.; Spinello, A.; Martorana, A.; Lauria, A.; Almerico, A.; Keppler, B.; Barone, G.
- Publication year: 2016
- Type: Articolo in rivista (Articolo in rivista)
- OA Link: http://hdl.handle.net/10447/214676
Abstract
Novel nickel(II) (1) and zinc(II) (2) complexes of a Salen-like ligand, carrying a pyrimidine ring on the N,N′ bridge, were synthesized and characterized. Their interaction with duplex and G-quadruplex DNA was investigated in aqueous solution through UV-visible absorption, circular dichroism and viscometry measurements. The results obtained point out that, while the zinc(II) complex does not interact with both duplex and G-quadruplex DNA, the nickel(II) complex 1 binds preferentially to G-quadruplex respect to duplex-DNA, with values of the DNA-binding constants, Kb, 2.6 × 105 M- 1 and 3.5 × 104 M- 1, respectively. Molecular dynamics simulations provided an atomic level model of the top-stacking binding occurring between 1 and hTelo (a 22-mer sequence oligonucleotide) in G-quadruplex conformation.