ABSTRACT
Understanding the effects of metabolism on the rational design of novel and more effective drugs is still a considerable challenge. To the best of our knowledge, there are no entirely computational strategies that make it possible to predict these effects. From this perspective, the development of such methodologies could contribute to significantly reduce the side effects of medicines, leading to the emergence of more effective and safer drugs. Thereby, in this study, our strategy is based on simulating the electron ionization mass spectrometry (EI-MS) fragmentation of the drug molecules and combined with molecular docking and ADMET models in two different situations. In the first model, the drug is docked without considering the possible metabolic effects. In the second model, each of the intermediates from the EI-MS results is docked, and metabolism occurs before the drug accesses the biological target. As a proof of concept, in this work, we investigate the main antiviral drugs used in clinical research to treat COVID-19. As a result, our strategy made it possible to assess the biological activity and toxicity of all potential by-products. We believed that our findings provide new chemical insights that can benefit the rational development of novel drugs in the future.
Subject(s)
Antiviral Agents/metabolism , COVID-19 Drug Treatment , Drug Discovery , SARS-CoV-2/drug effects , Adenine/adverse effects , Adenine/analogs & derivatives , Adenine/metabolism , Adenine/pharmacology , Adenosine/adverse effects , Adenosine/analogs & derivatives , Adenosine/metabolism , Adenosine/pharmacology , Adenosine Monophosphate/adverse effects , Adenosine Monophosphate/analogs & derivatives , Adenosine Monophosphate/metabolism , Adenosine Monophosphate/pharmacology , Alanine/adverse effects , Alanine/analogs & derivatives , Alanine/metabolism , Alanine/pharmacology , Amides/adverse effects , Amides/metabolism , Amides/pharmacology , Antiviral Agents/adverse effects , Antiviral Agents/pharmacology , COVID-19/metabolism , Chloroquine/adverse effects , Chloroquine/analogs & derivatives , Chloroquine/metabolism , Chloroquine/pharmacology , Drug Design , Humans , Metabolic Networks and Pathways , Molecular Docking Simulation , Nitro Compounds/adverse effects , Nitro Compounds/metabolism , Nitro Compounds/pharmacology , Pyrazines/adverse effects , Pyrazines/metabolism , Pyrazines/pharmacology , Pyrrolidines/adverse effects , Pyrrolidines/metabolism , Pyrrolidines/pharmacology , Ribavirin/adverse effects , Ribavirin/metabolism , Ribavirin/pharmacology , SARS-CoV-2/metabolism , Thiazoles/adverse effects , Thiazoles/metabolism , Thiazoles/pharmacologyABSTRACT
Replication of SARS-CoV-2, the coronavirus causing COVID-19, requires a main protease (Mpro) to cleave viral proteins. Consequently, Mpro is a target for antiviral agents. We and others previously demonstrated that GC376, a bisulfite prodrug with efficacy as an anti-coronaviral agent in animals, is an effective inhibitor of Mpro in SARS-CoV-2. Here, we report structure-activity studies of improved GC376 derivatives with nanomolar affinities and therapeutic indices >200. Crystallographic structures of inhibitor-Mpro complexes reveal that an alternative binding pocket in Mpro, S4, accommodates the P3 position. Alternative binding is induced by polar P3 groups or a nearby methyl. NMR and solubility studies with GC376 show that it exists as a mixture of stereoisomers and forms colloids in aqueous media at higher concentrations, a property not previously reported. Replacement of its Na+ counter ion with choline greatly increases solubility. The physical, biochemical, crystallographic, and cellular data reveal new avenues for Mpro inhibitor design.
Subject(s)
Antiviral Agents/pharmacology , Coronavirus 3C Proteases/antagonists & inhibitors , Cysteine Proteinase Inhibitors/pharmacology , Pyrrolidines/pharmacology , SARS-CoV-2/drug effects , Sulfonic Acids/pharmacology , Animals , Antiviral Agents/chemical synthesis , Antiviral Agents/metabolism , Binding Sites , Chlorocebus aethiops , Coronavirus 3C Proteases/chemistry , Coronavirus 3C Proteases/metabolism , Crystallography, X-Ray , Cysteine Proteinase Inhibitors/chemical synthesis , Cysteine Proteinase Inhibitors/metabolism , Humans , Micelles , Microbial Sensitivity Tests , Molecular Structure , Protein Binding , Pyrrolidines/chemical synthesis , Pyrrolidines/metabolism , SARS-CoV-2/enzymology , Solubility , Structure-Activity Relationship , Sulfonic Acids/chemical synthesis , Sulfonic Acids/metabolism , Vero CellsABSTRACT
Coronavirus disease 2019 (COVID-19) is an infectious disease, caused by a newly emerged highly pathogenic virus called novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Targeting the main protease (Mpro, 3CLpro) of SARS-CoV-2 is an appealing approach for drug development because this enzyme plays a significant role in the viral replication and transcription. The available crystal structures of SARS-CoV-2 Mpro determined in the presence of different ligands and inhibitor-like compounds provide a platform for the quick development of selective inhibitors of SARS-CoV-2 Mpro. In this study, we utilized the structural information of co-crystallized SARS-CoV-2 Mpro for the structure-guided drug discovery of high-affinity inhibitors from the PubChem database. The screened compounds were selected on the basis of their physicochemical properties, drug-likeliness, and strength of affinity to the SARS-CoV-2 Mpro. Finally, we have identified 6-Deaminosinefungin (PubChem ID: 10428963) and UNII-O9H5KY11SV (PubChem ID: 71481120) as potential inhibitors of SARS-CoV-2 Mpro which may be further exploited in drug development to address SARS-CoV-2 pathogenesis. Both compounds are structural analogs of known antivirals, having considerable protease inhibitory potential with improved pharmacological properties. All-atom molecular dynamics simulations suggested SARS-CoV-2 Mpro in complex with these compounds is stable during the simulation period with minimal structural changes. This work provides enough evidence for further implementation of the identified compounds in the development of effective therapeutics of COVID-19.
Subject(s)
Aminoglycosides/chemistry , Antiviral Agents/chemistry , Betacoronavirus/chemistry , Protease Inhibitors/chemistry , Pyrrolidines/chemistry , Viral Nonstructural Proteins/antagonists & inhibitors , Aminoglycosides/metabolism , Antiviral Agents/metabolism , Betacoronavirus/enzymology , COVID-19 , Catalytic Domain , Coronavirus 3C Proteases , Coronavirus Infections/drug therapy , Cysteine Endopeptidases/chemistry , Cysteine Endopeptidases/genetics , Cysteine Endopeptidases/metabolism , Drug Discovery , Gene Expression , Humans , Molecular Docking Simulation , Molecular Dynamics Simulation , Pandemics , Pneumonia, Viral/drug therapy , Protease Inhibitors/metabolism , Protein Binding , Protein Conformation, alpha-Helical , Protein Conformation, beta-Strand , Protein Interaction Domains and Motifs , Pyrrolidines/metabolism , SARS-CoV-2 , Substrate Specificity , Sulfonic Acids , Thermodynamics , User-Computer Interface , Viral Nonstructural Proteins/chemistry , Viral Nonstructural Proteins/genetics , Viral Nonstructural Proteins/metabolismABSTRACT
Porcine epidemic diarrhea virus (PEDV), being highly virulent and contagious in piglets, has caused significant damage to the pork industries of many countries worldwide. There are no commercial drugs targeting coronaviruses (CoVs), and few studies on anti-PEDV inhibitors. The coronavirus 3C-like protease (3CLpro) has a conserved structure and catalytic mechanism and plays a key role during viral polyprotein processing, thus serving as an appealing antiviral drug target. Here, we report the anti-PEDV effect of the broad-spectrum inhibitor GC376 (targeting 3Cpro or 3CLpro of viruses in the picornavirus-like supercluster). GC376 was highly effective against the PEDV 3CLpro and exerted similar inhibitory effects on two PEDV strains. Furthermore, the structure of the PEDV 3CLpro in complex with GC376 was determined at 1.65 Å. We elucidated structural details and analyzed the differences between GC376 binding with the PEDV 3CLpro and GC376 binding with the transmissible gastroenteritis virus (TGEV) 3CLpro. Finally, we explored the substrate specificity of PEDV 3CLpro at the P2 site and analyzed the effects of Leu group modification in GC376 on inhibiting PEDV infection. This study helps us to understand better the PEDV 3CLpro substrate specificity, providing information on the optimization of GC376 for development as an antiviral therapeutic against coronaviruses.
Subject(s)
Antiviral Agents/pharmacology , Peptide Hydrolases/chemistry , Porcine epidemic diarrhea virus/drug effects , Protease Inhibitors/pharmacology , Pyrrolidines/pharmacology , Animals , Antiviral Agents/chemistry , Antiviral Agents/metabolism , Catalytic Domain , Chlorocebus aethiops , Crystallography, X-Ray , Models, Molecular , Peptide Hydrolases/metabolism , Porcine epidemic diarrhea virus/enzymology , Porcine epidemic diarrhea virus/physiology , Protease Inhibitors/chemistry , Protease Inhibitors/metabolism , Pyrrolidines/chemistry , Pyrrolidines/metabolism , Substrate Specificity , Sulfonic Acids , Transmissible gastroenteritis virus/enzymology , Vero Cells , Virus Replication/drug effectsABSTRACT
The pandemic outbreak of a new coronavirus (CoV), SARS-CoV-2, has captured the world's attention, demonstrating that CoVs represent a continuous global threat. As this is a highly contagious virus, it is imperative to understand RNA-dependent-RNA-polymerase (RdRp), the key component in virus replication. Although the SARS-CoV-2 genome shares 80% sequence identity with severe acute respiratory syndrome SARS-CoV, their RdRps and nucleotidyl-transferases (NiRAN) share 98.1% and 93.2% identity, respectively. Sequence alignment of six coronaviruses demonstrated higher identity among their RdRps (60.9%-98.1%) and lower identity among their Spike proteins (27%-77%). Thus, a 3D structural model of RdRp, NiRAN, non-structural protein 7 (nsp7), and nsp8 of SARS-CoV-2 was generated by modeling starting from the SARS counterpart structures. Furthermore, we demonstrate the binding poses of three viral RdRp inhibitors (Galidesivir, Favipiravir, and Penciclovir), which were recently reported to have clinical significance for SARS-CoV-2. The network of interactions established by these drug molecules affirms their efficacy to inhibit viral RNA replication and provides an insight into their structure-based rational optimization for SARS-CoV-2 inhibition.