Bisabolangelone, a gastric H+/K+-ATPase inhibitor: homology modeling and docking study

The homology model of human gastric H+/K+-ATPase has been produced based on the template provided by pig gastric H+/K+-ATPase (PDB code: 3IXZ). After molecular mechanics optimization, induced-fit docking simulation between gastric H+/K+-ATPase and bisabolangelone that has significantly inhibition activity of H+/K+-ATPase was performed. The results of ligand docking showed that the binding pocket involves the amino acid residues Asp101, Asp102, Tyr105, Leu106, Val296, Phe297, Met299, Ala300, Tyr764, Tyr767, Leu774, Gly777, Cys778, Ile779, Gln889, Tyr893, and Ile952. The hydrogen bonds are formed between bisabolangelone and the amino acid residues Cys778, Gln889, and Tyr893.