Computational Studies on the Interaction of Arctiin and Liquiritin With β-lactoglobulin

摘要

The study of the interaction of drugs purified from natural sources and a transport protein, such as β-lactoglobulin (BLG), at the atomic level could be a valuable factor to control their transport to biological sites. In the present study, molecular docking and molecular dynamics simulation methods were used to study the interaction of arctiin and liquiritin as natural drugs and BLG as the transport protein. The molecular docking results indicated that these drugs bind in the internal cavity of BLG and the BLG affinity for binding the liquiritin is greater than arctiin. The docking results also indicated that the hydrogen bond interactions have a dominant role in the BLG-drug complex stability. The analysis of MD simulation trajectories showed that the root mean square deviation (RMSD) of BLG-liquiritin, unliganded BLG, and BLG-arctiin reached equilibrium and fluctuated around the mean value at about 1000, 3500, and 4000 ps, respectively. The time evolution of the radius of gyration and total solvent accessible surface of the protein showed that BLG-arctiin and BLG-liquiritin complexes became stable around 2500 and 5000 ps, respectively. Also, the profiles of atomic fluctuations during the simulation showed the rigidity of the ligand binding sites.