[Study on the interaction of quercetin with beta-glucosidase by fluorescence spectroscopy and molecular docking].

Combined with molecular docking model, a fluorescence method was applied to investigate the interaction between quercetin and beta-glucosidase and the acting mechanism. The interaction between beta-glucosidase and quercetin, as well as the enzyme inhibitor 4-nitrophenyl-beta-D-thioglucoside, was studied by the AutoDock4.2 molecular docking model, respectively. The binding reaction was simultaneously studied using fluorescence quenching method. The results showed that these interactions result in the endogenous fluorescence quenching of beta-glucosidase, which belongs to a static quenching mechanism. The calculated binding constants were 4.36 X 10(4), 4.04 x 10(4) and 3.18 x 10(4) L mol(-1) at 17, 27 and 37 degrees C, respectively. The results revealed that quercetin tended to bind with beta-glucosidase mainly by hydrogen bond and hydrophobic interaction, as well as electrostatic forces. Both fluorescence spectroscopy and molecular docking are complementary to each other for the investigation of the interaction between beta-glucosidase and quercetin from the experimental and theoretical view.