Screening methods of SARS-CoV-2 main protease inhibitors and current applications / 药学学报

COVID-19 epidemic continues to spread around the world till these days, and it is urgent to develop more safe and effective new drugs. Due to the limited P3 biosafety laboratories for directly screening inhibitors of virulent viruses with high infectivity, it is necessary to develop rapid and efficient screening methods for viral proteases and other related targets. The main protease (Mpro), which plays a key role in the replication cycle of SARS-CoV-2, is highly conserved and has no homologous proteases in humans, making it an ideal target for drug development. From two different levels, namely, molecular level and cellular level, this paper summarizes the reported screening methods of SARS-CoV-2 Mpro inhibitors through a variety of representative examples, expecting to provide references for further development of SARS-CoV-2 Mpro inhibitors.

Research progress of SARS-CoV-2 main protease inhibitors / 药学学报

As a common protease with high similarity among coronavirus species, the main protease (Mpro) of SARS-CoV-2 is responsible for the catalytic hydrolysis of viral precursor proteins into functional proteins, which is essential for coronavirus replication and is one of the ideal targets for the development of broad-spectrum antiviral drugs. This paper reviews the main protease inhibitors of SARS-CoV-2, including their molecular structures, potencies and drug-like profiles, binding modes and structure-activity relationships, etc.

Multi-level scoring approach to discover multi-targeting potency of medicinal plant phytochemicals against protein targets in SARS-CoV-2 and human ACE-2 receptor

SARS-CoV-2 pandemic has become a major threat to human healthcare and world economy. Due to the rapid spreading and deadly nature of infection, we are in a situation to develop quick therapeutics to combat SARS-CoV-2. In this study, we have adopted a multi-level scoring approach to identify multi-targeting potency of bioactive compounds in selected medicinal plants and compared its efficacy with two reference drugs, Nafamostat and Acalabrutinib which are under clinical trials to treat SARS-CoV-2. In particular, we employ molecular docking and implicit solvent free energy calculations (as implemented in the Molecular Mechanics -Generalized Born Surface Area approach) and QM fragmentation approach for validating the potency of bioactive compounds from the selected medicinal plants against four di?erent viral targets and one human receptor (Angiotensin-converting enzyme 2 -ACE-2) which facilitates the SARS-CoV-2entry into the cell. The protein targets considered for the study are viral 3CL main protease (3CLpro), papain-like protease (PLpro), RNA dependent RNA polymerase (RdRp), and viral spike protein-human hACE-2 complex (Spike:hACE2)including human protein target (hACE-2). Herein, thereliable multi-level scoring approach was used to validate the mechanism behind the multi-targeting potency of selected phytochemicals from medicinal plants. The present study evidenced that the phytochemicals Chebulagic acid, Stigmosterol, Repandusinic acid and Geranin exhibited efficient inhibitory activity against PLpro while Chebulagic acid was highly active against 3CLpro. Chebulagic acid andGeranin also showed excellent target specific activity against RdRp.Luteolin, Quercetin, Chrysoeriol and Repandusinic acid inhibited the interaction of viral spike protein with human ACE-2 receptor. Moreover Piperlonguminine and Piperine displayed significant inhibitory activity against human ACE-2 receptor. Therefore, the identified compounds namely Chebulagic acid, Geranin and Repandusinic acid can serve as potent multi-targeting phytomedicine for treating COVID-19

Computational evaluation of 2-arylbenzofurans for their potential use against SARS-CoV-2: A DFT, molecular docking, molecular dynamics simulation study

Natural compounds obtained from various sources have been used in the treatment of many diseases for many years and are very important compounds for drug development studies. They can also be an option to treat COVID-19, which is affecting the whole world and not curable with medication, yet. In this study, two 2-arylbenzofuran derivatives from Sesbania cannabina which are newly entered the literature were investigated computationally with the assistance of computational techniques including DFT calculations, molecular docking calculation and molecular dynamics simulations. The study consists of four parts, in the first part of the study DFT calculations were performed on the 2-arylbenzofurans, and geometry optimizations, vibrational analyses, molecular electrostatic potential (MEP) map calculations, frontier molecular orbital (FMO) calculations and Mulliken charge analyses were carried out.In the second part, molecular docking calculations were performed to investigate the interactions between the molecules and two potential target, SARS-CoV-2 main protease (SARS-CoV-2 Mpro) and SARS-CoV-2 spike receptor binding domain – human angiotensin converting enzyme 2 complex (SARS-CoV-2 SRBD – hACE2). In the third part, MD simulations were performed on the top-scoring ligand – receptor complexes to investigate the stability of the complex and the interactions between ligands and receptors in more detail. Finally, drug-likeness analyses and ADME (adsorption, desorption, metabolism, excretion) predictions were performed on the investigated compounds. Results showed that investigated natural compounds effectively interacted with the target receptors and gave comparable results to the reference drug molecules.

An overview of the anti-SARS-CoV-2 properties of Artemisia annua, its antiviral action, protein-associated mechanisms, and repurposing for COVID-19 treatment / 中西医结合学报

Artemisia annua and its phytocompounds have a rich history in the research and treatment of malaria, rheumatoid arthritis, systemic lupus erythematosus, and other diseases. Currently, the World Health Organization recommends artemisinin-based combination therapy as the first-line treatment for multi-drug-resistant malaria. Due to the various research articles on the use of antimalarial drugs to treat coronaviruses, a question is raised: would A. annua and its compounds provide anti-severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) properties? PubMed/MEDLINE, Scopus, and Google Scholar were searched for peer-reviewed articles that investigated the antiviral effects and mechanisms of A. annua and its phytochemicals against SARS-CoVs. Particularly, articles that evidenced the herb's role in inhibiting the coronavirus-host proteins were favored. Nineteen studies were retrieved. From these, fourteen in silico molecular docking studies demonstrated potential inhibitory properties of artemisinins against coronavirus-host proteins including 3CL

Optimization of expression conditions and determination the proteolytic activity of codon-optimized SARS-CoV-2 main protease in Escherichia coli / 生物工程学报

The main protease (Mpro) of SARS-CoV-2 is a highly conserved and mutation-resistant coronaviral enzyme, which plays a pivotal role in viral replication, making it an ideal target for the development of novel broad-spectrum anti-coronaviral drugs. In this study, a codon-optimized Mpro gene was cloned into pET-21a and pET-28a expression vectors. The recombinant plasmids were transformed into E. coli Rosetta(DE3) competent cells and the expression conditions were optimized. The highly expressed recombinant proteins, Mpro and Mpro-28, were purified by HisTrapTM chelating column and its proteolytic activity was determined by a fluorescence resonance energy transfer (FRET) assay. The FRET assay showed that Mpro exhibits a desirable proteolytic activity (25 000 U/mg), with Km and kcat values of 11.68 μmol/L and 0.037/s, respectively. The specific activity of Mpro is 25 times that of Mpro-28, a fusion protein carrying a polyhistidine tag at the N and C termini, indicating additional residues at the N terminus of Mpro, but not at the C terminus, are detrimental to its proteolytic activity. The preparation of active SARS-CoV-2 Mpro through codon-optimization strategy might facilitate the development of the rapid screening assays for the discovery of broad-spectrum anti-coronaviral drugs targeting Mpro.

Mutations in Main Protease of SARS CoV-2 Decreased Boceprevir Affinity

Abstract The coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a global health emergency. The main protease (Mpro) is crucial for the life cycle of coronaviruses. Boceprevir is a potential inhibitor and drug candidate for the Mpro of SARS-CoV-2. In this study, changes in the protein structure of the Mpro due to mutations in SARS-CoV-2 and the effects of these changes on boceprevir affinity, an important potential therapeutic agent, were investigated. The mutations were analyzed with RDP4 and MegaX. A three-dimensional model of mutant Mpro was generated by ProMod3. Qualitative Model Energy Analysis, ProSA, and MolProbity tools were used for structural validation and modeling of the wild-type and mutant Mpro proteins. Topological differences of the wild-type and mutant Mpro were calculated with the i-Tasser TM-Score. Molecular docking was performed using AutoDock 4.2. Functional dynamic structure models were created with DynOmics. Seven mutations (L89F, K90R, P108S, A191V, T224A, A234V and S254F) were detected in the Mpro of SARS-CoV-2. The mutations caused a decrease in the affinity of boceprevir, a potential protease inhibitor. The boceprevir was docked to the active site of Mpro, and the binding energies were −10.34 and −9.41 kcal.mol-1 for the wild-type and the mutant, respectively. The Debye-Waller factors calculated by elastic network model analysis were 0.58 and 0.64 Å2 for the wild-type Mpro and mutant Mpro, respectively. Mutations in structures that are important drug targets for SARS-CoV-2 may render existing therapeutics ineffective in its treatment.

Dual inhibition of COVID-19 spike glycoprotein and main protease 3CLpro by Withanone from Withania somnifera / 中草药·英文版

Objective: To identify the safe and effective natural inhibitors of spike glycoprotein and main protease 3CLpro using potential natural antiviral compounds which are studied under various animal models and viral cell lines. Methods: First, compounds were retrieved from the PubChem database and predicted for their druggability using the MolSoft web server, and compounds having drug-like property were predicted for major adverse drug reactions like cardiotoxicity, hepatotoxicity, arrhythmia, myocardial infarction, and nephrotoxicity using ADVERpred. Docking of nontoxic antiviral compounds with spike glycoprotein and main protease 3CLpro was performed using AutoDock vina by PyRx 0.8 version. The stability of compound-protein interactions was checked by molecular dynamic (MD) simulation using Schrodinger Desmond software. Results: Based on the druggable and nontoxic profile, nine compounds were selected. Among them, Withanone from Withania somnifera showed the highest binding affinity and best fit at active sites 1 of spike glycoprotein (glycosylation site) and main protease 3CLpro via interacting with active site amino acid residues before and after MD simulation at 50 ns. Withanone, which may reduce the glycosylation of SARS-CoV-2 via interacting with Asn343 and inhibit viral replication. Conclusion: The current study reports Withanone as a non-toxic antiviral against SARS-CoV-2 and serve as a potential lead hit for further experimental validation.