Physico-Chemical nanomaterials science
Mechanisms of the Interaction of Bovine Serum Albumin 
with Quercetin

Goncharova O. O.1, Dmytrenko O. P.1, Lesiuk A. I. 1, Kulish M. P.1,
Pavlenko O. L.1, Kanyuk M.I.2
1Physics Faculty, National Taras Shevchenko University of Kyiv, Glushkova prosp., 4, Kyiv-03039, Ukraine. 
E-mail: lesyuk.andrey@gmail.com
2 Palladin Institute of Biochemistry of the National Academy of Sciences of Ukraine, Leontovycha str, 9, Kyiv-01601, Ukraine.

The peculiarities of the complexation of the macromolecule of bovine serum albumin (BSA) and quercetin (Quer) were investigated. The obtained experimental data of the fluorescence spectra of aqueous BSA-Quer solutions indicated a static mechanism of the fluorescence quenching with the formation of molecular complexes. The established values ​​of the binding constant  and the number  of binding sites allowed to determine the thermodynamic parameters  and  of the interaction of molecules. Their values ​​indicated the hydrophobic nature of the binding in the complex, which was confirmed by the results of modeling by molecular dynamics. The binding energy  was calculated by the molecular docking method, which agrees well with the results obtained from the fluorescence spectra. The distance from Quer to the fluorescent tryptophan amino acid residues of the BSA molecule determined from the spectra by Forster theory corresponds to the simulation results. By the molecular dynamics of the BSA-Quer complex the temporal stability of the binding mode was shown and the conformational changes of the immediate amino acid environment of Quer as a result of the interaction were analyzed.