The papain-like protease(PLpro)is vital for the replication of coronaviruses(Co Vs),as well as for escaping innate-immune responses of the host.Hence,it has emerged as an attractive antiviral drug-target.In this study...The papain-like protease(PLpro)is vital for the replication of coronaviruses(Co Vs),as well as for escaping innate-immune responses of the host.Hence,it has emerged as an attractive antiviral drug-target.In this study,computational approaches were employed,mainly the structure-based virtual screening coupled with all-atom molecular dynamics(MD)simulations to computationally identify specific inhibitors of severe acute respiratory syndrome coronavirus 2(SARS-Co V-2)PLpro,which can be further developed as potential pan-PLprobased broad-spectrum antiviral drugs.The sequence,structure,and functional conserveness of most deadly human Co Vs PLprowere explored,and it was revealed that functionally important catalytic triad residues are well conserved among SARS-Co V,SARS-Co V-2,and middle east respiratory syndrome coronavirus(MERS-Co V).The subsequent screening of a focused protease inhibitors database composed of^7,000 compounds resulted in the identification of three candidate compounds,ADM13083841,LMG15521745,and SYN15517940.These three compounds established conserved interactions which were further explored through MD simulations,free energy calculations,and residual energy contribution estimated by MM-PB(GB)SA method.All these compounds showed stable conformation and interacted well with the active residues of SARS-Co V-2 PLpro,and showed consistent interaction profile with SARS-Co V PLproand MERS-Co V PLproas well.Conclusively,the reported SARS-Co V-2 PLprospecific compounds could serve as seeds for developing potent pan-PLprobased broad-spectrum antiviral drugs against deadly human coronaviruses.Moreover,the presented information related to binding site residual energy contribution could lead to further optimization of these compounds.展开更多
The global COVID-19 coronavirus pandemic has infected over 109 million people,leading to over 2 million deaths up to date and still lacking of effective drugs for patient treatment.Here,we screened about 1.8 million s...The global COVID-19 coronavirus pandemic has infected over 109 million people,leading to over 2 million deaths up to date and still lacking of effective drugs for patient treatment.Here,we screened about 1.8 million small molecules against the main protease(M^(pro))and papain like protease(PL^(pro)),two major proteases in severe acute respiratory syndrome-coronavirus 2 genome,and identified 1851M^(pro)inhibitors and 205 PL^(pro)inhibitors with low nmol/l activity of the best hits.Among these inhibitors,eight small molecules showed dual inhibition effects on both M^(pro)and PL^(pro),exhibiting potential as better candidates for COVID-19 treatment.The best inhibitors of each protease were tested in antiviral assay,with over 40%of M^(pro)inhibitors and over 20%of PL^(pro)inhibitors showing high potency in viral inhibition with low cytotoxicity.The X-ray crystal structure of SARS-CoV-2 M^(pro)in complex with its potent inhibitor 4a was determined at 1.8Åresolution.Together with docking assays,our results provide a comprehensive resource for future research on anti-SARS-CoV-2 drug development.展开更多
SARS coronavirus (SARS-CoV) develops an antagonis- tic mechanism by which to evade the antiviral activities of interferon (IFN). Previous studies suggested that SARS-CoV papain-like protease (PLpro) inhibits act...SARS coronavirus (SARS-CoV) develops an antagonis- tic mechanism by which to evade the antiviral activities of interferon (IFN). Previous studies suggested that SARS-CoV papain-like protease (PLpro) inhibits activa- tion of the IRF3 pathway, which would normally elicit a robust IFN response, but the mechanism(s) used by SARS PLpro to inhibit activation of the IRF3 pathway is not fully known. In this study, we uncovered a novel mechanism that may explain how SARS PLpro effi- ciently inhibits activation of the IRF3 pathway. We found that expression of the membrane-anchored PLpro domain (PLpro-TM) from SARS-CoV inhibits STING/ TBKl/IKKE-mediated activation of type I IFNs and dis- rupts the phosphorylation and dimerization of IRF3, which are activated by STING and TBKI. Meanwhile, we showed that PLpro-TM physically interacts with TRAF3, TBK1, IKK~, STING, and IRF3, the key components that assemble the STING-TRAF3-TBK1 complex for activa- tion of IFN expression. However, the interaction between the components in STING-TRAF3-TBK1 complex is dis- rupted by PLpro-TM. Furthermore, SARS PLpro-TM reduces the levels of ubiquitinated forms of RIG-I, STING, TRAF3, TBK1, and IRF3 in the STING-TRAF3- TBK1 complex. These results collectively point to a new mechanism used by SARS-CoV through which PLpro negatively regulates IRF3 activation by interaction withSTING-TRAF3-TBK1 complex, yielding a SARS-CoV countermeasure against host innate immunity.展开更多
The papain-like protease(PL^(pro)) of Middle-East respiratory syndrome coronavirus(MERS-CoV) has proteolytic,deubiquitinating,and de ISGylating activities.The latter two are involved in the suppression of the antivira...The papain-like protease(PL^(pro)) of Middle-East respiratory syndrome coronavirus(MERS-CoV) has proteolytic,deubiquitinating,and de ISGylating activities.The latter two are involved in the suppression of the antiviral innate immune response of the host cell.To contribute to an understanding of this process,we present here the X-ray crystal structure of a complex between MERS-CoV PL^(pro) and human ubiquitin(Ub) that is devoid of any covalent linkage between the two proteins.Five regions of the PL^(pro) bind to two areas of the Ub.The C-terminal five residues of Ub,RLRGG,are similar to the P5–P1 residues of the polyprotein substrates of the PL^(pro) and are responsible for the major part of the interaction between the two macromolecules.Through sitedirected mutagenesis,we demonstrate that conserved Asp165 and non-conserved Asp164 are important for the catalytic activities of MERS-CoV PL^(pro).The enzyme appears not to be optimized for catalytic efficiency; thus,replacement of Phe269 by Tyr leads to increased peptidolytic and deubiquitinating activities.Ubiquitin binding by MERS-CoV PL^(pro) involves remarkable differences compared to the corresponding complex with SARS-CoV PL^(pro).The structure and the mutational study help understand common and unique features of the deubiquitinating activity of MERS-CoV PL^(pro).展开更多
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 identif...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.There-fore,it is an attractive target for antiviral drug develop-ment.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 pmol/L.These compounds also exhibit strong antiviral activities in cell-based assays.YM155,an anti-cancer 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 repur-posing strategy,which has led to the discovery of new drug leads with clinical potential for COVID-19 treatments.展开更多
It is an urgent demand worldwide to control the coronavirus disease 2019(COVID-19)pandemic caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)virus.The 3-chymotrypsin-like protease(3CL^(pro))and ...It is an urgent demand worldwide to control the coronavirus disease 2019(COVID-19)pandemic caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)virus.The 3-chymotrypsin-like protease(3CL^(pro))and papain-like protease(PL^(pro))are key targets to discover SARS-CoV-2 inhibitors.After screening 12 Chinese herbal medicines and 125 compounds from licorice,we found that a popular natural product schaftoside inhibited 3CL^(pro)and PL^(pro)with IC_(50)values of 1.73±0.22 and 3.91±0.19μmol/L,respectively,and inhibited SARS CoV-2 virus in Vero E6 cells with EC_(50)of 11.83±3. 23μmol/L. Hydrogen-deuterium exchange mass spectrometry analysis, quantum mechanics/molecular mechanics calculations, together with site-directed mutagenesis indicated the antiviral activities of schaftoside were related with non-covalent interactions with H41, G143 and R188 of3CLpro, and K157, E167 and A246 of PLpro. Moreover, proteomics analysis and cytokine assay revealed that schaftoside also regulated immune response and inflammation of the host cells. The antiinflammatory activities of schaftoside were confirmed on lipopolysaccharide-induced acute lung injury mice. Schaftoside showed good safety and pharmacokinetic property, and could be a promising drug candidate for the prevention and treatment of COVID-19.展开更多
基金the Starting Research Grant for High-level Talents from Guangxi Universitythe Postdoctoral Project from Guangxi University。
文摘The papain-like protease(PLpro)is vital for the replication of coronaviruses(Co Vs),as well as for escaping innate-immune responses of the host.Hence,it has emerged as an attractive antiviral drug-target.In this study,computational approaches were employed,mainly the structure-based virtual screening coupled with all-atom molecular dynamics(MD)simulations to computationally identify specific inhibitors of severe acute respiratory syndrome coronavirus 2(SARS-Co V-2)PLpro,which can be further developed as potential pan-PLprobased broad-spectrum antiviral drugs.The sequence,structure,and functional conserveness of most deadly human Co Vs PLprowere explored,and it was revealed that functionally important catalytic triad residues are well conserved among SARS-Co V,SARS-Co V-2,and middle east respiratory syndrome coronavirus(MERS-Co V).The subsequent screening of a focused protease inhibitors database composed of^7,000 compounds resulted in the identification of three candidate compounds,ADM13083841,LMG15521745,and SYN15517940.These three compounds established conserved interactions which were further explored through MD simulations,free energy calculations,and residual energy contribution estimated by MM-PB(GB)SA method.All these compounds showed stable conformation and interacted well with the active residues of SARS-Co V-2 PLpro,and showed consistent interaction profile with SARS-Co V PLproand MERS-Co V PLproas well.Conclusively,the reported SARS-Co V-2 PLprospecific compounds could serve as seeds for developing potent pan-PLprobased broad-spectrum antiviral drugs against deadly human coronaviruses.Moreover,the presented information related to binding site residual energy contribution could lead to further optimization of these compounds.
基金supported by the National Key R&D Program of China 2018YFA0507000(B.W,Q.Z.),2018ZX09735001(Y.J.)and 2020YFC0844500(J.L.),the National Science Foundation of China grants 31825010(B.W.),81525024(Q.Z.),81673489(J.L),the Key Research Program of Frontier Sciences,CAS grants QYZDB-SSWSMC024(B.W.)and QYZDB-SSW-SMC054(Q.Z.),Fund of Chinese Academy of Sciences 2020YJFK0105(J.L.),Chinese Academy of Engineering and Jack Ma Foundation 2020-CMKYGG-05(J.D.),the Shanghai Science and Technology Development Funds 20431900200(J.L.)and K.C.Wong Education Foundation(J.L.),Fund of Youth Innovation Promotion Association 2018319(X.C.),and the Hubei Science and Technology Project 2020FCA003(G.X.).Fund of Chinese Academy of Sciences 2020YJFK0105(J.L.)。
文摘The global COVID-19 coronavirus pandemic has infected over 109 million people,leading to over 2 million deaths up to date and still lacking of effective drugs for patient treatment.Here,we screened about 1.8 million small molecules against the main protease(M^(pro))and papain like protease(PL^(pro)),two major proteases in severe acute respiratory syndrome-coronavirus 2 genome,and identified 1851M^(pro)inhibitors and 205 PL^(pro)inhibitors with low nmol/l activity of the best hits.Among these inhibitors,eight small molecules showed dual inhibition effects on both M^(pro)and PL^(pro),exhibiting potential as better candidates for COVID-19 treatment.The best inhibitors of each protease were tested in antiviral assay,with over 40%of M^(pro)inhibitors and over 20%of PL^(pro)inhibitors showing high potency in viral inhibition with low cytotoxicity.The X-ray crystal structure of SARS-CoV-2 M^(pro)in complex with its potent inhibitor 4a was determined at 1.8Åresolution.Together with docking assays,our results provide a comprehensive resource for future research on anti-SARS-CoV-2 drug development.
文摘SARS coronavirus (SARS-CoV) develops an antagonis- tic mechanism by which to evade the antiviral activities of interferon (IFN). Previous studies suggested that SARS-CoV papain-like protease (PLpro) inhibits activa- tion of the IRF3 pathway, which would normally elicit a robust IFN response, but the mechanism(s) used by SARS PLpro to inhibit activation of the IRF3 pathway is not fully known. In this study, we uncovered a novel mechanism that may explain how SARS PLpro effi- ciently inhibits activation of the IRF3 pathway. We found that expression of the membrane-anchored PLpro domain (PLpro-TM) from SARS-CoV inhibits STING/ TBKl/IKKE-mediated activation of type I IFNs and dis- rupts the phosphorylation and dimerization of IRF3, which are activated by STING and TBKI. Meanwhile, we showed that PLpro-TM physically interacts with TRAF3, TBK1, IKK~, STING, and IRF3, the key components that assemble the STING-TRAF3-TBK1 complex for activa- tion of IFN expression. However, the interaction between the components in STING-TRAF3-TBK1 complex is dis- rupted by PLpro-TM. Furthermore, SARS PLpro-TM reduces the levels of ubiquitinated forms of RIG-I, STING, TRAF3, TBK1, and IRF3 in the STING-TRAF3- TBK1 complex. These results collectively point to a new mechanism used by SARS-CoV through which PLpro negatively regulates IRF3 activation by interaction withSTING-TRAF3-TBK1 complex, yielding a SARS-CoV countermeasure against host innate immunity.
基金supported by the European Commission through its "SILVER" project (contract no.HEALTHF3-2010-260644)the German Center for Infection Research (DZIF)support by the DFG Cluster of Excellence "Inflammation at Interfaces" (EXC 306)
文摘The papain-like protease(PL^(pro)) of Middle-East respiratory syndrome coronavirus(MERS-CoV) has proteolytic,deubiquitinating,and de ISGylating activities.The latter two are involved in the suppression of the antiviral innate immune response of the host cell.To contribute to an understanding of this process,we present here the X-ray crystal structure of a complex between MERS-CoV PL^(pro) and human ubiquitin(Ub) that is devoid of any covalent linkage between the two proteins.Five regions of the PL^(pro) bind to two areas of the Ub.The C-terminal five residues of Ub,RLRGG,are similar to the P5–P1 residues of the polyprotein substrates of the PL^(pro) and are responsible for the major part of the interaction between the two macromolecules.Through sitedirected mutagenesis,we demonstrate that conserved Asp165 and non-conserved Asp164 are important for the catalytic activities of MERS-CoV PL^(pro).The enzyme appears not to be optimized for catalytic efficiency; thus,replacement of Phe269 by Tyr leads to increased peptidolytic and deubiquitinating activities.Ubiquitin binding by MERS-CoV PL^(pro) involves remarkable differences compared to the corresponding complex with SARS-CoV PL^(pro).The structure and the mutational study help understand common and unique features of the deubiquitinating activity of MERS-CoV PL^(pro).
基金National Key R&D Program of China grants 2017YFC0840300(Z.R.)and 2020YFA0707500(H.Y.)Project of International Cooperation and Exchanges NSFC(Grant No.81520108019 to Z.R.)+3 种基金Science and Technology Commission of Shanghai Municipality(Grant No.20431900200 to H.Y.)Department of Science and Technology of Guangxi Zhuang Autonomous Region(Grant No.2020AB40007 to X.Y.)Hubei Science and Technology Project(Grant No.2020FCA003 to L.Z.)Youth Program of NSFC(Grant No.81900729 to L.S.).
文摘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.There-fore,it is an attractive target for antiviral drug develop-ment.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 pmol/L.These compounds also exhibit strong antiviral activities in cell-based assays.YM155,an anti-cancer 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 repur-posing strategy,which has led to the discovery of new drug leads with clinical potential for COVID-19 treatments.
基金supported by National Natural Science Foundation of China(Nos.81891010/81891011,81725023,82003614,82173950,31770192,32070187 and 82003681)China Postdoctoral Science Foundation(2022T150029,China)+1 种基金the National Key Research and Development Program of China(No.2017-YFC1700405)the Science&Technology Department of Xinjiang Uygur Autonomous Region(2018AB012,China)。
文摘It is an urgent demand worldwide to control the coronavirus disease 2019(COVID-19)pandemic caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)virus.The 3-chymotrypsin-like protease(3CL^(pro))and papain-like protease(PL^(pro))are key targets to discover SARS-CoV-2 inhibitors.After screening 12 Chinese herbal medicines and 125 compounds from licorice,we found that a popular natural product schaftoside inhibited 3CL^(pro)and PL^(pro)with IC_(50)values of 1.73±0.22 and 3.91±0.19μmol/L,respectively,and inhibited SARS CoV-2 virus in Vero E6 cells with EC_(50)of 11.83±3. 23μmol/L. Hydrogen-deuterium exchange mass spectrometry analysis, quantum mechanics/molecular mechanics calculations, together with site-directed mutagenesis indicated the antiviral activities of schaftoside were related with non-covalent interactions with H41, G143 and R188 of3CLpro, and K157, E167 and A246 of PLpro. Moreover, proteomics analysis and cytokine assay revealed that schaftoside also regulated immune response and inflammation of the host cells. The antiinflammatory activities of schaftoside were confirmed on lipopolysaccharide-induced acute lung injury mice. Schaftoside showed good safety and pharmacokinetic property, and could be a promising drug candidate for the prevention and treatment of COVID-19.