Molecular Modeling Study for the Evaluation of Natural Compounds as Potential Lanosterol 14α-demethylase Inhibitors

Abstract

Background: Candida albicans is one of the most important causes of fatal fungal infections. Ergosterol, the main sterol in the fungal cell membrane, is the resultant product of Lanosterol in the presence of the enzyme Lanosterolα-demethylase (Cytochrome P450DM). This enzyme is the target enzyme of azole antifungal agents. Aim: To evaluate the antifungal potency of some of the natural compounds via molecular modeling and Absorption, Distribution, Metabolism and Excretion (ADME) study. Method: The study involved the selection and modeling of the target enzyme, followed by the refinement of the model using molecular dynamic simulation. The modelled structure of the enzyme was validated using the Ramachandran plot and Sequence determination technique. A series of natural compounds was evaluated for cytochrome P450 inhibitory activity using molecular docking studies. The structures of compounds were prepared using a Chem sketch, and molecular docking was performed using Molergo Virtual Docker (MVD) program. Results: The docking study indicated that all the natural compounds have interactivity with protein residue of 14α-demethylase, and the heme prosthetic group and water molecules are present at the active site. The data were also correlated with the synthetic compounds that were experimentally inactive against the fungus and had a low docking score. The compounds with a high dock score were further screened for Absorption, Distribution, Metabolism, Excretion and Toxicity (ADMET) profile, and it was predicted that these compounds can be used as lead with a good ADME profile and low toxicity. Conclusion: The natural compound, i.e., curcumin, can easily be used further for lead optimization.