Computational Determination of Potential Inhibitors of SARS-CoV‑2 Main Protease

• Published in: Journal of chemical information and modeling 2020-12, Vol.60 (12), p.5771-5780
• Main Authors: Ngo, Son Tung, Quynh Anh Pham, Ngoc, Thi Le, Ly, Pham, Duc-Hung, Vu, Van V
• Format: Article
• Language: English
• Subjects: Alanine; Amino Acid Sequence; Antiviral Agents - chemistry; Antiviral Agents - metabolism; Antiviral Agents - pharmacology; Binding; Binding energy; Binding Sites; Biological Products - chemistry; Biological Products - pharmacology; Computational Chemistry; COVID-19 - drug therapy; Darunavir - chemistry; Darunavir - pharmacology; Databases, Factual; Drug Design; Drugs; Free energy; Glucosides - chemistry; Glucosides - pharmacology; HIV Protease - metabolism; HIV Protease Inhibitors - chemistry; HIV Protease Inhibitors - metabolism; HIV Protease Inhibitors - pharmacology; Humans; Molecular docking; Molecular Docking Simulation; Peptides - chemistry; Perturbation; Phenols - chemistry; Phenols - pharmacology; Protease; Protease inhibitors; Protein Binding; SARS-CoV-2 - drug effects; Severe acute respiratory syndrome coronavirus 2; Structure-Activity Relationship; Thermodynamics; Viral diseases
• ISSN: 1549-9596; 1549-960X
• DOI: 10.1021/acs.jcim.0c00491

The novel coronavirus (SARS-CoV-2) has infected several million people and caused thousands of deaths worldwide since December 2019. As the disease is spreading rapidly all over the world, it is urgent to find effective drugs to treat the virus. The main protease (Mpro) of SARS-CoV-2 is one of the potential drug targets. Therefore, in this context, we used rigorous computational methods, including molecular docking, fast pulling of ligand (FPL), and free energy perturbation (FEP), to investigate potential inhibitors of SARS-CoV-2 Mpro. We first tested our approach with three reported inhibitors of SARS-CoV-2 Mpro, and our computational results are in good agreement with the respective experimental data. Subsequently, we applied our approach on a database of ∼4600 natural compounds, as well as 8 available HIV-1 protease (PR) inhibitors and an aza-peptide epoxide. Molecular docking resulted in a short list of 35 natural compounds, which was subsequently refined using the FPL scheme. FPL simulations resulted in five potential inhibitors, including three natural compounds and two available HIV-1 PR inhibitors. Finally, FEP, the most accurate and precise method, was used to determine the absolute binding free energy of these five compounds. FEP results indicate that two natural compounds, cannabisin A and isoacteoside, and an HIV-1 PR inhibitor, darunavir, exhibit a large binding free energy to SARS-CoV-2 Mpro, which is larger than that of 13b, the most reliable SARS-CoV-2 Mpro inhibitor recently reported. The binding free energy largely arises from van der Waals interaction. We also found that Glu166 forms H-bonds to all of the inhibitors. Replacing Glu166 by an alanine residue leads to ∼2.0 kcal/mol decreases in the affinity of darunavir to SARS-CoV-2 Mpro. Our results could contribute to the development of potential drugs inhibiting SARS-CoV-2.