Docking studies on monoamine oxidase-B inhibitors: Estimation of inhibition constants (Ki) of a series of experimentally tested compounds

Monoamine oxidase (EC1.4.3.4; MAO) is a mitochondrial outer membrane flavoenzyme that catalyzes the oxidation of biogenic amines. It has two distinct isozymic forms designated MAO-A and MAO-B, each displaying different substrate and inhibitor specificities. They are the well-known targets for antidepressant and neuroprotective drugs. Elucidation of the X-ray crystallographic structure of MAO-B has opened the way for molecular modeling studies. A series of experimentally tested (1–10) model compounds has been docked computationally to the active site of the MAO-B enzyme. The AutoDock 3.0.5 program was employed to perform automated molecular docking. The free energies of binding (ΔG) and inhibition constants (Ki) of the docked compounds were calculated by the Lamarckian Genetic Algorithm (LGA) of AutoDock 3.0.5. Excellent to good correlations between the calculated and experimental Ki values were obtained.