Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 9 de 9
Filter
1.
Cell Rep ; 39(5): 110770, 2022 05 03.
Article in English | MEDLINE | ID: covidwho-1859379

ABSTRACT

The emergence of the SARS-CoV-2 Omicron variant is dominant in many countries worldwide. The high number of spike mutations is responsible for the broad immune evasion from existing vaccines and antibody drugs. To understand this, we first present the cryo-electron microscopy structure of ACE2-bound SARS-CoV-2 Omicron spike. Comparison to previous spike antibody structures explains how Omicron escapes these therapeutics. Secondly, we report structures of Omicron, Delta, and wild-type spikes bound to a patient-derived Fab antibody fragment (510A5), which provides direct evidence where antibody binding is greatly attenuated by the Omicron mutations, freeing spike to bind ACE2. Together with biochemical binding and 510A5 neutralization assays, our work establishes principles of binding required for neutralization and clearly illustrates how the mutations lead to antibody evasion yet retain strong ACE2 interactions. Structural information on spike with both bound and unbound antibodies collectively elucidates potential strategies for generation of therapeutic antibodies.


Subject(s)
COVID-19 , SARS-CoV-2 , Angiotensin-Converting Enzyme 2 , Antibodies, Neutralizing , Antibodies, Viral , Cryoelectron Microscopy , Humans , Immunoglobulin Fab Fragments , Spike Glycoprotein, Coronavirus
2.
Proc Natl Acad Sci U S A ; 119(16): e2117142119, 2022 04 19.
Article in English | MEDLINE | ID: covidwho-1774040

ABSTRACT

The main protease (Mpro) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a key enzyme, which extensively digests CoV replicase polyproteins essential for viral replication and transcription, making it an attractive target for antiviral drug development. However, the molecular mechanism of how Mpro of SARS-CoV-2 digests replicase polyproteins, releasing the nonstructural proteins (nsps), and its substrate specificity remain largely unknown. Here, we determine the high-resolution structures of SARS-CoV-2 Mpro in its resting state, precleavage state, and postcleavage state, constituting a full cycle of substrate cleavage. The structures show the delicate conformational changes that occur during polyprotein processing. Further, we solve the structures of the SARS-CoV-2 Mpro mutant (H41A) in complex with six native cleavage substrates from replicase polyproteins, and demonstrate that SARS-CoV-2 Mpro can recognize sequences as long as 10 residues but only have special selectivity for four subsites. These structural data provide a basis to develop potent new inhibitors against SARS-CoV-2.


Subject(s)
Coronavirus 3C Proteases , Coronavirus RNA-Dependent RNA Polymerase , SARS-CoV-2 , Antiviral Agents/chemistry , Coronavirus 3C Proteases/chemistry , Coronavirus RNA-Dependent RNA Polymerase/chemistry , Coronavirus RNA-Dependent RNA Polymerase/genetics , Polyproteins/chemistry , Protein Conformation , Proteolysis , SARS-CoV-2/enzymology , Substrate Specificity/genetics
4.
Protein Cell ; 12(11): 877-888, 2021 11.
Article in English | MEDLINE | ID: covidwho-1188202

ABSTRACT

A new coronavirus (SARS-CoV-2) has been identified as the etiologic agent for the COVID-19 outbreak. Currently, effective treatment options remain very limited for this disease; therefore, there is an urgent need to identify new anti-COVID-19 agents. In this study, we screened over 6,000 compounds that included approved drugs, drug candidates in clinical trials, and pharmacologically active compounds to identify leads that target the SARS-CoV-2 papain-like protease (PLpro). Together with main protease (Mpro), PLpro is responsible for processing the viral replicase polyprotein into functional units. Therefore, it is an attractive target for antiviral drug development. Here we discovered four compounds, YM155, cryptotanshinone, tanshinone I and GRL0617 that inhibit SARS-CoV-2 PLpro with IC50 values ranging from 1.39 to 5.63 µmol/L. These compounds also exhibit strong antiviral activities in cell-based assays. YM155, an anticancer drug candidate in clinical trials, has the most potent antiviral activity with an EC50 value of 170 nmol/L. In addition, we have determined the crystal structures of this enzyme and its complex with YM155, revealing a unique binding mode. YM155 simultaneously targets three "hot" spots on PLpro, including the substrate-binding pocket, the interferon stimulating gene product 15 (ISG15) binding site and zinc finger motif. Our results demonstrate the efficacy of this screening and repurposing strategy, which has led to the discovery of new drug leads with clinical potential for COVID-19 treatments.


Subject(s)
Coronavirus Papain-Like Proteases/chemistry , High-Throughput Screening Assays/methods , Protease Inhibitors/chemistry , Antiviral Agents/chemistry , Antiviral Agents/metabolism , Antiviral Agents/therapeutic use , Binding Sites , COVID-19/drug therapy , COVID-19/virology , Coronavirus Papain-Like Proteases/genetics , Coronavirus Papain-Like Proteases/metabolism , Crystallography, X-Ray , Drug Evaluation, Preclinical , Drug Repositioning , Humans , Imidazoles/chemistry , Imidazoles/metabolism , Imidazoles/therapeutic use , Inhibitory Concentration 50 , Molecular Dynamics Simulation , Mutagenesis, Site-Directed , Naphthoquinones/chemistry , Naphthoquinones/metabolism , Naphthoquinones/therapeutic use , Protease Inhibitors/metabolism , Protease Inhibitors/therapeutic use , Protein Structure, Tertiary , Recombinant Proteins/biosynthesis , Recombinant Proteins/chemistry , Recombinant Proteins/isolation & purification , SARS-CoV-2/isolation & purification
5.
Nature ; 582(7811): 289-293, 2020 06.
Article in English | MEDLINE | ID: covidwho-608904

ABSTRACT

A new coronavirus, known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is the aetiological agent responsible for the 2019-2020 viral pneumonia outbreak of coronavirus disease 2019 (COVID-19)1-4. Currently, there are no targeted therapeutic agents for the treatment of this disease, and effective treatment options remain very limited. Here we describe the results of a programme that aimed to rapidly discover lead compounds for clinical use, by combining structure-assisted drug design, virtual drug screening and high-throughput screening. This programme focused on identifying drug leads that target main protease (Mpro) of SARS-CoV-2: Mpro is a key enzyme of coronaviruses and has a pivotal role in mediating viral replication and transcription, making it an attractive drug target for SARS-CoV-25,6. We identified a mechanism-based inhibitor (N3) by computer-aided drug design, and then determined the crystal structure of Mpro of SARS-CoV-2 in complex with this compound. Through a combination of structure-based virtual and high-throughput screening, we assayed more than 10,000 compounds-including approved drugs, drug candidates in clinical trials and other pharmacologically active compounds-as inhibitors of Mpro. Six of these compounds inhibited Mpro, showing half-maximal inhibitory concentration values that ranged from 0.67 to 21.4 µM. One of these compounds (ebselen) also exhibited promising antiviral activity in cell-based assays. Our results demonstrate the efficacy of our screening strategy, which can lead to the rapid discovery of drug leads with clinical potential in response to new infectious diseases for which no specific drugs or vaccines are available.


Subject(s)
Betacoronavirus/chemistry , Cysteine Endopeptidases/chemistry , Drug Discovery/methods , Models, Molecular , Protease Inhibitors/chemistry , Viral Nonstructural Proteins/antagonists & inhibitors , Viral Nonstructural Proteins/chemistry , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Betacoronavirus/drug effects , COVID-19 , Cells, Cultured/virology , Coronavirus 3C Proteases , Coronavirus Infections/enzymology , Coronavirus Infections/virology , Drug Design , Drug Evaluation, Preclinical , Humans , Pandemics , Pneumonia, Viral/enzymology , Pneumonia, Viral/virology , Protease Inhibitors/pharmacology , Protein Structure, Tertiary , SARS-CoV-2
6.
Cell ; 182(2): 417-428.e13, 2020 07 23.
Article in English | MEDLINE | ID: covidwho-342735

ABSTRACT

Nucleotide analog inhibitors, including broad-spectrum remdesivir and favipiravir, have shown promise in in vitro assays and some clinical studies for COVID-19 treatment, this despite an incomplete mechanistic understanding of the viral RNA-dependent RNA polymerase nsp12 drug interactions. Here, we examine the molecular basis of SARS-CoV-2 RNA replication by determining the cryo-EM structures of the stalled pre- and post- translocated polymerase complexes. Compared with the apo complex, the structures show notable structural rearrangements happening to nsp12 and its co-factors nsp7 and nsp8 to accommodate the nucleic acid, whereas there are highly conserved residues in nsp12, positioning the template and primer for an in-line attack on the incoming nucleotide. Furthermore, we investigate the inhibition mechanism of the triphosphate metabolite of remdesivir through structural and kinetic analyses. A transition model from the nsp7-nsp8 hexadecameric primase complex to the nsp12-nsp7-nsp8 polymerase complex is also proposed to provide clues for the understanding of the coronavirus transcription and replication machinery.


Subject(s)
Betacoronavirus/chemistry , Betacoronavirus/enzymology , RNA-Dependent RNA Polymerase/chemistry , Viral Nonstructural Proteins/chemistry , Adenosine Monophosphate/analogs & derivatives , Adenosine Monophosphate/chemistry , Adenosine Monophosphate/metabolism , Adenosine Monophosphate/pharmacology , Alanine/analogs & derivatives , Alanine/chemistry , Alanine/metabolism , Alanine/pharmacology , Antiviral Agents/chemistry , Antiviral Agents/metabolism , Antiviral Agents/pharmacology , Catalytic Domain , Coronavirus RNA-Dependent RNA Polymerase , Cryoelectron Microscopy , Models, Chemical , Models, Molecular , RNA, Viral/metabolism , SARS-CoV-2 , Transcription, Genetic , Virus Replication
7.
Nat Struct Mol Biol ; 27(6): 529-532, 2020 06.
Article in English | MEDLINE | ID: covidwho-222247

ABSTRACT

The antineoplastic drug carmofur is shown to inhibit the SARS-CoV-2 main protease (Mpro). Here, the X-ray crystal structure of Mpro in complex with carmofur reveals that the carbonyl reactive group of carmofur is covalently bound to catalytic Cys145, whereas its fatty acid tail occupies the hydrophobic S2 subsite. Carmofur inhibits viral replication in cells (EC50 = 24.30 µM) and is a promising lead compound to develop new antiviral treatment for COVID-19.


Subject(s)
Betacoronavirus/enzymology , Cysteine Endopeptidases/chemistry , Fluorouracil/analogs & derivatives , Viral Nonstructural Proteins/antagonists & inhibitors , Viral Nonstructural Proteins/chemistry , Animals , Betacoronavirus/drug effects , COVID-19 , Chlorocebus aethiops , Coronavirus 3C Proteases , Coronavirus Infections/virology , Cysteine Endopeptidases/genetics , Cysteine Endopeptidases/metabolism , Fluorouracil/chemistry , Fluorouracil/pharmacology , Models, Molecular , Pandemics , Pneumonia, Viral/virology , SARS-CoV-2 , Vero Cells , Viral Nonstructural Proteins/genetics , Viral Nonstructural Proteins/metabolism
8.
Science ; 368(6497): 1331-1335, 2020 06 19.
Article in English | MEDLINE | ID: covidwho-108792

ABSTRACT

SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) is the etiological agent responsible for the global COVID-19 (coronavirus disease 2019) outbreak. The main protease of SARS-CoV-2, Mpro, is a key enzyme that plays a pivotal role in mediating viral replication and transcription. We designed and synthesized two lead compounds (11a and 11b) targeting Mpro Both exhibited excellent inhibitory activity and potent anti-SARS-CoV-2 infection activity. The x-ray crystal structures of SARS-CoV-2 Mpro in complex with 11a or 11b, both determined at a resolution of 1.5 angstroms, showed that the aldehyde groups of 11a and 11b are covalently bound to cysteine 145 of Mpro Both compounds showed good pharmacokinetic properties in vivo, and 11a also exhibited low toxicity, which suggests that these compounds are promising drug candidates.


Subject(s)
Antiviral Agents/chemistry , Betacoronavirus/enzymology , Drug Design , Viral Nonstructural Proteins/antagonists & inhibitors , Animals , Antiviral Agents/pharmacology , Betacoronavirus/drug effects , COVID-19 , Catalytic Domain , Chlorocebus aethiops , Coronavirus 3C Proteases , Coronavirus Infections/drug therapy , Cysteine Endopeptidases , Dogs , Drug Evaluation, Preclinical , Female , Humans , Male , Mice , Molecular Structure , Pandemics , Pneumonia, Viral/drug therapy , Protein Structure, Tertiary , Rats, Sprague-Dawley , SARS-CoV-2 , Toxicity Tests , Vero Cells
9.
Science ; 368(6492): 779-782, 2020 05 15.
Article in English | MEDLINE | ID: covidwho-47347

ABSTRACT

A novel coronavirus [severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2)] outbreak has caused a global coronavirus disease 2019 (COVID-19) pandemic, resulting in tens of thousands of infections and thousands of deaths worldwide. The RNA-dependent RNA polymerase [(RdRp), also named nsp12] is the central component of coronaviral replication and transcription machinery, and it appears to be a primary target for the antiviral drug remdesivir. We report the cryo-electron microscopy structure of COVID-19 virus full-length nsp12 in complex with cofactors nsp7 and nsp8 at 2.9-angstrom resolution. In addition to the conserved architecture of the polymerase core of the viral polymerase family, nsp12 possesses a newly identified ß-hairpin domain at its N terminus. A comparative analysis model shows how remdesivir binds to this polymerase. The structure provides a basis for the design of new antiviral therapeutics that target viral RdRp.


Subject(s)
Betacoronavirus/enzymology , RNA-Dependent RNA Polymerase/chemistry , RNA-Dependent RNA Polymerase/ultrastructure , Viral Nonstructural Proteins/chemistry , Viral Nonstructural Proteins/ultrastructure , Adenosine Monophosphate/analogs & derivatives , Adenosine Monophosphate/metabolism , Adenosine Monophosphate/pharmacology , Alanine/analogs & derivatives , Alanine/metabolism , Alanine/pharmacology , Antiviral Agents/metabolism , Antiviral Agents/pharmacology , Catalytic Domain , Coronavirus RNA-Dependent RNA Polymerase , Cryoelectron Microscopy , Drug Design , Models, Molecular , Multiprotein Complexes/chemistry , Multiprotein Complexes/metabolism , Multiprotein Complexes/ultrastructure , Protein Conformation, beta-Strand , Protein Domains , RNA-Dependent RNA Polymerase/antagonists & inhibitors , RNA-Dependent RNA Polymerase/metabolism , SARS-CoV-2 , Viral Nonstructural Proteins/antagonists & inhibitors , Viral Nonstructural Proteins/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL