Structure modeling and docking study of HCV NS5B-3a RNA polymerase for the identification of potent inhibitors

Homology modeling in combination with molecular docking studies has been applied to predict the binding modes of the Hepatitis C virus (HCV) NS5B-3a inhibitors within the pocket of NS5B polymerase of HCV genotype 3a. Structure modeling and docking using Genetic Optimization for Ligand Docking (GOLD) were carried out to understand the ligand binding properties of NS5B-3a and to identify a potent inhibitor against it. The three-dimensional homology model of Pakistani strain is not available and was built based on the HCV-J4 NS5B polymerase structure. Compound 1 possessing high GOLD fitness score of 62.17 with IC50 value of 0.04 μM was selected as the potent inhibitor. The docking analysis depicted that hydrogen bonding, ionic and hydrophobic interactions contributed significantly for its ligand binding and the amino acid residues Arg442 and His403 seemed to be the anchor residues for receptor recognition. For developing a connection between the experimental bioactivities and GOLD fitness scores, a squared correlation coefficient was calculated and found as acceptable with the value of r ² = 0.67. These findings may act as potent lead in designing effective NS5B-3a inhibitors.