Spectroscopic and molecular modeling studies of binding interaction between the new complex of yttrium and 1,10-phenanthroline derivatives with DNA and BSA.

In this study, the 4,9 diazafluoren-9-one ligand and [Y(Daf)2Cl3.OH2] complex were synthesized. The interaction of this complex with DNA and bovine serum albumin (BSA) was investigated by UV-vis and fluorescence spectroscopy. The molecular docking method was used to confirm the experimental results, investigate the type of interaction, and determine the binding site. The binding constant and Stern-Volmer constant were calculated using spectroscopy techniques. The binding constant of the Y-complex with DNA and BSA obtained using the UV-vis technique was 1.61 × 105 M-1 and 0.49 × 105 M-1, while that obtained using the fluorescence method was 3.39 × 105 M-1 and 3.63 × 105 M-1, respectively. The results of experimental and theoretical data showed that the interaction between the yttrium complex and DNA and BSA is driven by the hydrogen bond and van der Waals interaction, respectively. The yttrium complex communicates with DNA via the groove interaction. This complex has high binding energy with bovine serum albumin. In addition, the molecular docking results showed that the complex binds to the IIA subdomain of BSA (site I). Finally, anticancer activity of the yttrium complex was studied on MCF-7 and A549 cell lines by using the MTT method. The IC50 values obtained showed that the yttrium complex possesses anticancer activity.

An insight into the interaction between malachite green oxalate with human serum albumin: Molecular dynamic simulation and spectroscopic approaches.

Cationic triarylmethane dyes such as malachite green are aromatic xenobiotic compounds causing environmental pollution. The affinity between hazardous materials and biomolecules makes it important to understand the properties of such compounds. Accordingly, in this study, the possible molecular interaction between this pollutant and the human serum albumin (HSA) was investigated using a combination of molecular docking, molecular dynamic simulation and multi-spectroscopic approaches. The docking results illustrated that malachite green oxalate (MGO) could bind to some of the HSA amino acids with the estimated free energy = -32.93 kJ/mol. Further, the results of the dynamic simulation revealed that MGO had a steady interaction with the protein though increasing flexibility and decreasing the HSA compactness. These results were, therefore, in agreement with those obtained by spectroscopic techniques. The MGO concentration of 0.0005 mM could quench the HSA's intrinsic fluorescence by %16.88. The protein structural changes also revealed that the binding interaction of MGO-HSA was accompanied by an increase in the α-helix and a decrease in the ß-sheet of the protein. Overall, this study indicated the suitable molecular modeling interaction of MGO and HSA.