Experimental and theoretical investigation of bezafibrate binding to serum albumins

The purpose of this investigation was to provide insight into the possible mechanism of the intermolecular interactions between antilipemic agent bezafibrate and serum albumins (SAs) including human (HSA) and bovine (BSA). The aim was to indicate the most probable sight of these interactions. Both experimental (spectroscopic) and theoretical methods were applied. It was determined that bezafibrate binds to SAs in one specific binding site, the fatty acid binding site 6. The results obtained from the steady-state and time-resolved fluorescence experiments suggested that existing two distinct stable conformations of the proteins with different exposure to the quencher. The dominate conformer of HSA and BSA characterized by the Stern-Volmer quenching constant (from ratio F0/F) equal to 1.24·104 and 8.48·103 M−1 at 298 K, respectively. The docking results and calculated thermodynamics parameters may be suggested that the binding process is spontaneous and might involve van der Waals and hydrogen bonding forces.