Interaction of a Vanadyl Schiff Base Complex with DNA and BSA: A Combination of Experimental and Computational Studies

Background and Purpose: Cancer is the primary cause of death in the world. Vanadium (IV) is a metal ion complex which has been proposed as a suitable candidate for cancer treatment. In this study, the interaction of the oxido-vanadium (IV) complex [VOL(bipy)] with salmon sperm DNA and Bovine Serum Albumin (BSA) was investigated through experimental and computational approaches. With the results of this experimental study, the mechanism and parameters related to the interaction of [VOL(bipy)] with DNA and BSA were determined. Materials and Methods: The kinetic interaction of DNA and BSA with [VOL(bipy)] was determined using absorption titration and fluorescence quenching, respectively. Moreover, the possible interactions were calculated by molecular docking prediction using the available software. Results: The binding constant (Kb) of the complex-DNA interaction was calculated to be 2.34×10⁴ M^-1, indicating a relatively strong interaction between the complex and DNA. It was found that the V(IV) complex interacted with DNA through the groove binding mode followed by partial intercalation into the DNA helix. The Kb values obtained for [VOL(bipy)]-BSA interaction were in the range of 1.07×10³-5.82×10⁴ M^-1. The V(IV) complex was found to prefer the domain I binding pocket of BSA with the ΔGb value of -7.52 kcal/mol. Conclusion: Both experimental and computational analyses confirmed the interaction of the vanadium complex with DNA and BSA. The moderate affinity of [VOL(bipy)] for BSA indicates that this protein is a good candidate for transferring the complex.