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Ullah S, Zheng Z, Rahman W, Ullah F, Ullah A, Iqbal MN, Iqbal N, Gao T. A computational approach to fighting type 1 diabetes by targeting 2C Coxsackie B virus protein with flavonoids. PLoS One 2023; 18:e0290576. [PMID: 37647325 PMCID: PMC10468086 DOI: 10.1371/journal.pone.0290576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 08/11/2023] [Indexed: 09/01/2023] Open
Abstract
Autoimmune diabetes, well-known as type 1 insulin-dependent diabetic mellitus (T1D). T1D is a prolonged condition marked by an inadequate supply of insulin. The lack is brought on by pancreatic cell death and results in hyperglycemia. The immune system, genetic predisposition, and environmental variables are just a few of the many elements that contribute significantly to the pathogenicity of T1D disease. In this study, we test flavonoids against Coxsackie virus protein to cope the type 1 diabetes. After protein target identification we perform molecular docking of flavonoids and selected target (1z8r). then performed the ADMET analysis and select the top compound the base of the docking score and the ADMET test analysis. Following that molecular dynamics simulation was performed up to 300 ns. Root means square deviation, root mean square fluctuation, secondary structure elements, and protein-ligand contacts were calculated as post-analysis of simulation. We further check the binding of the ligand with protein by performing MM-GBSA every 10 ns. Lead compound CID_5280445 was chosen as a possible medication based on analysis. The substance is non-toxic, meets the ADMET and BBB likeness requirements, and has the best interaction energy. This work will assist researchers in developing medicine and testing it as a treatment for Diabetes Mellitus Type 1 brought on by Coxsackie B4 viruses by giving them an understanding of chemicals against these viruses.
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Affiliation(s)
| | - Zilong Zheng
- Big Data Center, The Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen, P. R. China
| | | | | | - Anees Ullah
- S Khan Lab Mardan, Khyber Pakhtunkhwa, Pakistan
| | - Muhammad Nasir Iqbal
- Department of Bioinformatics, Institute of Biochemistry, Biotechnology and Bioinformatics, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Naveed Iqbal
- Department of Bioinformatics, Institute of Biochemistry, Biotechnology and Bioinformatics, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Tianshun Gao
- Big Data Center, The Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen, P. R. China
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2
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Neuhaus D. Zinc finger structure determination by NMR: Why zinc fingers can be a handful. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2022; 130-131:62-105. [PMID: 36113918 PMCID: PMC7614390 DOI: 10.1016/j.pnmrs.2022.07.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 07/09/2022] [Accepted: 07/10/2022] [Indexed: 06/07/2023]
Abstract
Zinc fingers can be loosely defined as protein domains containing one or more tetrahedrally-co-ordinated zinc ions whose role is to stabilise the structure rather than to be involved in enzymatic chemistry; such zinc ions are often referred to as "structural zincs". Although structural zincs can occur in proteins of any size, they assume particular significance for very small protein domains, where they are often essential for maintaining a folded state. Such small structures, that sometimes have only marginal stability, can present particular difficulties in terms of sample preparation, handling and structure determination, and early on they gained a reputation for being resistant to crystallisation. As a result, NMR has played a more prominent role in structural studies of zinc finger proteins than it has for many other types of proteins. This review will present an overview of the particular issues that arise for structure determination of zinc fingers by NMR, and ways in which these may be addressed.
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Affiliation(s)
- David Neuhaus
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK.
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3
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Lasrado N, Gangaplara A, Arumugam R, Massilamany C, Pokal S, Zhou Y, Xiang SH, Steffen D, Reddy J. Identification of Immunogenic Epitopes That Permit the Detection of Antigen-Specific T Cell Responses in Multiple Serotypes of Group B Coxsackievirus Infections. Viruses 2020; 12:v12030347. [PMID: 32245257 PMCID: PMC7150766 DOI: 10.3390/v12030347] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 03/20/2020] [Accepted: 03/20/2020] [Indexed: 02/07/2023] Open
Abstract
Coxsackievirus group B (CVB) contains six serotypes that can affect various organs. Some of these organ-specific diseases such as myocarditis and pancreatitis can be caused by more than one serotype. Thus, development of immunological tools common to multiple serotypes is desired. This is especially critical for analyzing antigen-specific T cell responses at a single cell level. To this end, we made efforts to identify the immunogenic epitopes of CVB3 leading us to localize three T cell epitopes within the viral protein 1 (VP1) namely, VP1 681-700, VP1 721-740 and VP1 771-790. First, we confirmed their immunogenicity in the immunization settings. Second, we sought to verify the ability of VP1 epitopes to bind major histocompatibility complex (MHC) class II (IAk) molecules. Third, we created MHC class II (IAk) dextramers and tetramers and ascertained the T cell responses to be antigen-specific. Fourth, we analyzed the T cell responses in animals infected with CVB3 and noted the magnitude of antigen-specific T cell responses occurring in the order of VP1 721-740 and VP1 681-700 followed by VP1 771-790 as verified by proliferation assay and IAk tetramer staining. All epitopes induced interferon (IFN)-γ as a major cytokine. Finally, we investigated whether the VP1 tools generated for CVB3 can also be used to verify T cell responses in infections caused by other serotypes. To this end, we established the CVB4 infection model in A/J mice and found that the CVB4 infection led to the induction of IFN-γ-producing T cell responses primarily for VP1 721-740 and VP1 681-700. Thus, the VP1-specific tools, particularly IAk tetramers can be used to monitor anti-viral T cell responses in multiple CVB serotypes.
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Affiliation(s)
- Ninaad Lasrado
- School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, NE 68503, USA; (N.L.); (A.G.); (R.A.); (C.M.); (S.-H.X.); (D.S.)
| | - Arunakumar Gangaplara
- School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, NE 68503, USA; (N.L.); (A.G.); (R.A.); (C.M.); (S.-H.X.); (D.S.)
| | - Rajkumar Arumugam
- School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, NE 68503, USA; (N.L.); (A.G.); (R.A.); (C.M.); (S.-H.X.); (D.S.)
| | - Chandirasegaran Massilamany
- School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, NE 68503, USA; (N.L.); (A.G.); (R.A.); (C.M.); (S.-H.X.); (D.S.)
| | - Sayli Pokal
- Department of Statistics, University of Nebraska-Lincoln, Lincoln, NE 68503, USA; (S.P.); (Y.Z.)
| | - Yuzhen Zhou
- Department of Statistics, University of Nebraska-Lincoln, Lincoln, NE 68503, USA; (S.P.); (Y.Z.)
| | - Shi-Hua Xiang
- School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, NE 68503, USA; (N.L.); (A.G.); (R.A.); (C.M.); (S.-H.X.); (D.S.)
| | - David Steffen
- School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, NE 68503, USA; (N.L.); (A.G.); (R.A.); (C.M.); (S.-H.X.); (D.S.)
| | - Jay Reddy
- School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, NE 68503, USA; (N.L.); (A.G.); (R.A.); (C.M.); (S.-H.X.); (D.S.)
- Correspondence:
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4
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Sofy AR, Hmed AA, Abd El Haliem NF, Zein MAE, Elshaarawy RF. Polyphosphonium-oligochitosans decorated with nanosilver as new prospective inhibitors for common human enteric viruses. Carbohydr Polym 2019; 226:115261. [DOI: 10.1016/j.carbpol.2019.115261] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 07/20/2019] [Accepted: 08/27/2019] [Indexed: 01/14/2023]
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5
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Validating Enterovirus D68-2A pro as an Antiviral Drug Target and the Discovery of Telaprevir as a Potent D68-2A pro Inhibitor. J Virol 2019; 93:JVI.02221-18. [PMID: 30674624 DOI: 10.1128/jvi.02221-18] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 01/11/2019] [Indexed: 02/08/2023] Open
Abstract
Enterovirus D68 (EV-D68) is a viral pathogen that leads to severe respiratory illness and has been linked with the development of acute flaccid myelitis (AFM) in children. No vaccines or antivirals are currently available for EV-D68 infection, and treatment options for hospitalized patients are limited to supportive care. Here, we report the expression of the EV-D68 2A protease (2Apro) and characterization of its enzymatic activity. Furthermore, we discovered that telaprevir, an FDA-approved drug used for the treatment of hepatitis C virus (HCV) infections, is a potent antiviral against EV-D68 by targeting the 2Apro enzyme. Using a fluorescence resonance energy transfer-based substrate cleavage assay, we showed that the purified EV-D68 2Apro has proteolytic activity selective against a peptide sequence corresponding to the viral VP1-2A polyprotein junction. Telaprevir inhibits EV-D68 2Apro through a nearly irreversible, biphasic binding mechanism. In cell culture, telaprevir showed submicromolar-to-low-micromolar potency against several recently circulating neurotropic strains of EV-D68 in different human cell lines. To further confirm the antiviral drug target, serial viral passage experiments were performed to select for resistance against telaprevir. An N84T mutation near the active site of 2Apro was identified in resistant viruses, and this mutation reduced the potency of telaprevir in both the enzymatic and cellular antiviral assays. Collectively, we report for the first time the in vitro enzymatic activity of EV-D68 2Apro and the identification of telaprevir as a potent EV-D68 2Apro inhibitor. These findings implicate EV-D68 2Apro as an antiviral drug target and highlight the repurposing potential of telaprevir to treat EV-D68 infection.IMPORTANCE A 2014 EV-D68 outbreak in the United States has been linked to the development of acute flaccid myelitis in children. Unfortunately, no treatment options against EV-D68 are currently available, and the development of effective therapeutics is urgently needed. Here, we characterize and validate a new EV-D68 drug target, the 2Apro, and identify telaprevir-an FDA-approved drug used to treat hepatitis C virus (HCV) infections-as a potent antiviral with a novel mechanism of action toward 2Apro 2Apro functions as a viral protease that cleaves a peptide sequence corresponding to the VP1-2A polyprotein junction. The binding of telaprevir potently inhibits its enzymatic activity, and using drug resistance selection, we show that the potent antiviral activity of telaprevir was due to 2Apro inhibition. This is the first inhibitor to selectively target the 2Apro from EV-D68 and can be used as a starting point for the development of therapeutics with selective activity against EV-D68.
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Ling H, Yang P, Hou H, Sun Y. Structural view of the 2A protease from human rhinovirus C15. Acta Crystallogr F Struct Biol Commun 2018; 74:255-261. [PMID: 29633974 PMCID: PMC5894110 DOI: 10.1107/s2053230x18003382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 02/27/2018] [Indexed: 11/10/2022] Open
Abstract
The majority of outbreaks of the common cold are caused by rhinoviruses. The 2A protease (2Apro) of human rhinoviruses (HRVs) is known to play important roles in the propagation of the virus and the modulation of host signal pathways to facilitate viral replication. The 2Apro from human rhinovirus C15 (HRV-C15) has been expressed in Escherichia coli and purified by affinity chromatography, ion-exchange chromatography and gel-filtration chromatography. The crystals diffracted to 2.6 Å resolution. The structure was solved by molecular replacement using the structure of 2Apro from coxsackievirus A16 (CVA16) as the search model. The structure contains a conserved His-Asp-Cys catalytic triad and a Zn2+-binding site. Comparison with other 2Apro structures from enteroviruses reveals that the substrate-binding cleft of 2Apro from HRV-C15 exhibits a more open conformation, which presumably favours substrate binding.
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Affiliation(s)
- Hui Ling
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, People’s Republic of China
| | - Pan Yang
- National Laboratory of Macromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, People’s Republic of China
| | - Hai Hou
- School of Life Sciences, Northwestern Polytechnical University, Xi’an 710072, People’s Republic of China
| | - Yao Sun
- National Laboratory of Macromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, People’s Republic of China
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7
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Interaction of 2A proteinase of human rhinovirus genetic group A with eIF4E is required for eIF4G cleavage during infection. Virology 2017; 511:123-134. [DOI: 10.1016/j.virol.2017.08.020] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 08/11/2017] [Accepted: 08/14/2017] [Indexed: 01/04/2023]
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8
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Yang X, Cheng A, Wang M, Jia R, Sun K, Pan K, Yang Q, Wu Y, Zhu D, Chen S, Liu M, Zhao XX, Chen X. Structures and Corresponding Functions of Five Types of Picornaviral 2A Proteins. Front Microbiol 2017; 8:1373. [PMID: 28785248 PMCID: PMC5519566 DOI: 10.3389/fmicb.2017.01373] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 07/06/2017] [Indexed: 11/27/2022] Open
Abstract
Among the few non-structural proteins encoded by the picornaviral genome, the 2A protein is particularly special, irrespective of structure or function. During the evolution of the Picornaviridae family, the 2A protein has been highly non-conserved. We believe that the 2A protein in this family can be classified into at least five distinct types according to previous studies. These five types are (A) chymotrypsin-like 2A, (B) Parechovirus-like 2A, (C) hepatitis-A-virus-like 2A, (D) Aphthovirus-like 2A, and (E) 2A sequence of the genus Cardiovirus. We carried out a phylogenetic analysis and found that there was almost no homology between each type. Subsequently, we aligned the sequences within each type and found that the functional motifs in each type are highly conserved. These different motifs perform different functions. Therefore, in this review, we introduce the structures and functions of these five types of 2As separately. Based on the structures and functions, we provide suggestions to combat picornaviruses. The complexity and diversity of the 2A protein has caused great difficulties in functional and antiviral research. In this review, researchers can find useful information on the 2A protein and thus conduct improved antiviral research.
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Affiliation(s)
- Xiaoyao Yang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural UniversityChengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China
| | - Anchun Cheng
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural UniversityChengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China
| | - Mingshu Wang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural UniversityChengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China
| | - Renyong Jia
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural UniversityChengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China
| | - Kunfeng Sun
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural UniversityChengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China
| | - Kangcheng Pan
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural UniversityChengdu, China
| | - Qiao Yang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural UniversityChengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China
| | - Ying Wu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural UniversityChengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China
| | - Dekang Zhu
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural UniversityChengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China
| | - Shun Chen
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural UniversityChengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China
| | - Mafeng Liu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural UniversityChengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China
| | - Xin-Xin Zhao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural UniversityChengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China
| | - Xiaoyue Chen
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural UniversityChengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China
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9
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Gunaseelan S, Chu JJH. Identifying novel antiviral targets against enterovirus 71: where are we? Future Virol 2017. [DOI: 10.2217/fvl-2016-0144] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Human enterovirus 71 (HEV71) has been considered as an essential human pathogen, which causes hand, foot and mouth disease in young children. Several HEV71 outbreaks have been observed in many Asia-Pacific countries for the past two decades with significant fatalities. However, there are no competent vaccines or antivirals against HEV71 infection to date. Thus, it is of critical priority to delve into the search for anti-HEV71 agents. Prior to this, there is a need to gain knowledge about the distinct targets of HEV71 that are available and that have been exploited for antiviral therapy. This review aims to provide a better understanding of HEV71 virology and feature potential antivirals for progressive clinical development with respect to their elucidated mechanistic actions.
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Affiliation(s)
- Saravanan Gunaseelan
- Laboratory of Molecular RNA Virology & Antiviral Strategies, Department of Microbiology & Immunology, Yong Loo Lin School of Medicine, National University Health System, 5 Science Drive 2, National University of Singapore, 117597 Singapore
| | - Justin Jang Hann Chu
- Laboratory of Molecular RNA Virology & Antiviral Strategies, Department of Microbiology & Immunology, Yong Loo Lin School of Medicine, National University Health System, 5 Science Drive 2, National University of Singapore, 117597 Singapore
- Institute of Molecular & Cell Biology, Agency for Science, Technology & Research (A*STAR), 61 Biopolis Drive, Proteos #06–05, Singapore 138673
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10
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Al-Salahi R, Abuelizz HA, Ghabbour HA, El-Dib R, Marzouk M. Molecular docking study and antiviral evaluation of 2-thioxo-benzo[g]quinazolin-4(3H)-one derivatives. Chem Cent J 2016; 10:21. [PMID: 27099618 PMCID: PMC4837545 DOI: 10.1186/s13065-016-0168-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Accepted: 04/07/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The persistent appearance of viral strains that causes a resistant viral infection has led to continuous trials for the design and development of novel antiviral compounds. Benzoquinazoline compounds have been reported to exhibit an interesting antiviral activity. This work aims to study and evaluate the antiviral activity of a newly prepared 2-thioxo-benzo[g]quinazolin-4(3H)-one series against herpes simplex (HSV-1 & 2) and coxsackievirus (CVB4). METHODS The antiviral activity was performed using the MTT assay, in which Vero cells (obtained from the American Type Culture Collection, ATCC) were propagated in fresh Dulbecco's Modified Eagle's Medium (DMEM) and challenged with 10(4) doses of the virus. Thereafter, the cultures were treated simultaneously with two-fold serial dilutions of the tested compound and incubated at 37 °C for 48 h. Molecular docking studies were done on the CVB4 2A proteinase enzyme using Molegro Virtual Docker software. RESULTS The cytotoxicity (CC50), effective concentration (EC50) and the selectivity index (SI) values were determined. Based on their EC50 values, a number of the investigated compounds demonstrated weak to moderate activity relative to their parents. Accordingly, compounds 5-9, 11, 15-18, 21, 22, 24, 25, 27 and 28 were active against CVB4, and compounds 5 and 24 were active against HSV-1 and 2 in comparison to ribavirin and acyclovir, which were used as reference drugs. CONCLUSION The obtained results gave us some useful insights about the characteristic requirements for future trials to build up and design more active and selective antiviral 2-thioxo-benzo[g]quinazolin-4(3H)-one agents.Graphical abstractCompound 24 superimposed with Ribavirin in CV B4 2A Proteinase enzyme (PDB: 1Z8R) active site.
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Affiliation(s)
- Rashad Al-Salahi
- />Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, P. O. Box 2457, Riyadh, 11451 Saudi Arabia
| | - Hatem A. Abuelizz
- />Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, P. O. Box 2457, Riyadh, 11451 Saudi Arabia
| | - Hazem A. Ghabbour
- />Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, P. O. Box 2457, Riyadh, 11451 Saudi Arabia
| | - Rabab El-Dib
- />Department of Pharmacognosy, College of Pharmacy, King Saud University, P.O. Box 22452, Riyadh, 11495 Saudi Arabia
- />Department of Pharmacognosy, Faculty of Pharmacy, Helwan University, Cairo, 11795 Egypt
| | - Mohamed Marzouk
- />Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, P. O. Box 2457, Riyadh, 11451 Saudi Arabia
- />Chemistry of Natural Products Group, Center of Excellence for Advanced Sciences, National Research Center, Dokki, Cairo, 12622 Egypt
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11
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Aumayr M, Fedosyuk S, Ruzicska K, Sousa-Blin C, Kontaxis G, Skern T. NMR analysis of the interaction of picornaviral proteinases Lb and 2A with their substrate eukaryotic initiation factor 4GII. Protein Sci 2015; 24:1979-96. [PMID: 26384734 PMCID: PMC4815241 DOI: 10.1002/pro.2807] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Revised: 09/14/2015] [Accepted: 09/17/2015] [Indexed: 11/09/2022]
Abstract
Messenger RNA is recruited to the eukaryotic ribosome by a complex including the eukaryotic initiation factor (eIF) 4E (the cap-binding protein), the scaffold protein eIF4G and the RNA helicase eIF4A. To shut-off host-cell protein synthesis, eIF4G is cleaved during picornaviral infection by a virally encoded proteinase; the structural basis of this reaction and its stimulation by eIF4E is unclear. We have structurally and biochemically investigated the interaction of purified foot-and-mouth disease virus (FMDV) leader proteinase (Lb(pro)), human rhinovirus 2 (HRV2) 2A proteinase (2A(pro)) and coxsackievirus B4 (CVB4) 2A(pro) with purified eIF4GII, eIF4E and the eIF4GII/eIF4E complex. Using nuclear magnetic resonance (NMR), we completed (13)C/(15) N sequential backbone assignment of human eIF4GII residues 551-745 and examined their binding to murine eIF4E. eIF4GII551-745 is intrinsically unstructured and remains so when bound to eIF4E. NMR and biophysical techniques for determining stoichiometry and binding constants revealed that the papain-like Lb(pro) only forms a stable complex with eIF4GII(551-745) in the presence of eIF4E, with KD values in the low nanomolar range; Lb(pro) contacts both eIF4GII and eIF4E. Furthermore, the unrelated chymotrypsin-like 2A(pro) from HRV2 and CVB4 also build a stable complex with eIF4GII/eIF4E, but with K(D) values in the low micromolar range. The HRV2 enzyme also forms a stable complex with eIF4E; however, none of the proteinases tested complex stably with eIF4GII alone. Thus, these three picornaviral proteinases have independently evolved to establish distinct triangular heterotrimeric protein complexes that may actively target ribosomes involved in mRNA recruitment to ensure efficient host cell shut-off.
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Affiliation(s)
- Martina Aumayr
- Department of Medical Biochemistry, Max F. Perutz Laboratories, Medical University of Vienna, Vienna Biocenter, Dr. Bohr-Gasse 9/3, Vienna, A-1030, Austria
| | - Sofiya Fedosyuk
- Department of Medical Biochemistry, Max F. Perutz Laboratories, Medical University of Vienna, Vienna Biocenter, Dr. Bohr-Gasse 9/3, Vienna, A-1030, Austria
| | - Katharina Ruzicska
- Department of Medical Biochemistry, Max F. Perutz Laboratories, Medical University of Vienna, Vienna Biocenter, Dr. Bohr-Gasse 9/3, Vienna, A-1030, Austria
| | - Carla Sousa-Blin
- Department of Medical Biochemistry, Max F. Perutz Laboratories, Medical University of Vienna, Vienna Biocenter, Dr. Bohr-Gasse 9/3, Vienna, A-1030, Austria
| | - Georg Kontaxis
- Department of Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Campus Vienna Biocenter 5, Vienna, A-1030, Austria
| | - Tim Skern
- Department of Medical Biochemistry, Max F. Perutz Laboratories, Medical University of Vienna, Vienna Biocenter, Dr. Bohr-Gasse 9/3, Vienna, A-1030, Austria
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12
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Martínez-Salas E, Francisco-Velilla R, Fernandez-Chamorro J, Lozano G, Diaz-Toledano R. Picornavirus IRES elements: RNA structure and host protein interactions. Virus Res 2015; 206:62-73. [PMID: 25617758 DOI: 10.1016/j.virusres.2015.01.012] [Citation(s) in RCA: 98] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 01/05/2015] [Accepted: 01/12/2015] [Indexed: 01/26/2023]
Abstract
Internal ribosome entry site (IRES) elements were discovered in picornaviruses. These elements are cis-acting RNA sequences that adopt diverse three-dimensional structures and recruit the translation machinery using a 5' end-independent mechanism assisted by a subset of translation initiation factors and various RNA binding proteins termed IRES transacting factors (ITAFs). Many of these factors suffer important modifications during infection including cleavage by picornavirus proteases, changes in the phosphorylation level and/or redistribution of the protein from the nuclear to the cytoplasm compartment. Picornavirus IRES are amongst the most potent elements described so far. However, given their large diversity and complexity, the mechanistic basis of its mode of action is not yet fully understood. This review is focused to describe recent advances on the studies of RNA structure and RNA-protein interactions modulating picornavirus IRES activity.
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Affiliation(s)
- Encarnación Martínez-Salas
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas - Universidad Autónoma de Madrid, Nicolas Cabrera 1, 28049 Madrid, Spain.
| | - Rosario Francisco-Velilla
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas - Universidad Autónoma de Madrid, Nicolas Cabrera 1, 28049 Madrid, Spain
| | - Javier Fernandez-Chamorro
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas - Universidad Autónoma de Madrid, Nicolas Cabrera 1, 28049 Madrid, Spain
| | - Gloria Lozano
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas - Universidad Autónoma de Madrid, Nicolas Cabrera 1, 28049 Madrid, Spain
| | - Rosa Diaz-Toledano
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas - Universidad Autónoma de Madrid, Nicolas Cabrera 1, 28049 Madrid, Spain
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13
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Structural basis for host membrane remodeling induced by protein 2B of hepatitis A virus. J Virol 2015; 89:3648-58. [PMID: 25589659 DOI: 10.1128/jvi.02881-14] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
UNLABELLED The complexity of viral RNA synthesis and the numerous participating factors require a mechanism to topologically coordinate and concentrate these multiple viral and cellular components, ensuring a concerted function. Similarly to all other positive-strand RNA viruses, picornaviruses induce rearrangements of host intracellular membranes to create structures that act as functional scaffolds for genome replication. The membrane-targeting proteins 2B and 2C, their precursor 2BC, and protein 3A appear to be primarily involved in membrane remodeling. Little is known about the structure of these proteins and the mechanisms by which they induce massive membrane remodeling. Here we report the crystal structure of the soluble region of hepatitis A virus (HAV) protein 2B, consisting of two domains: a C-terminal helical bundle preceded by an N-terminally curved five-stranded antiparallel β-sheet that displays striking structural similarity to the β-barrel domain of enteroviral 2A proteins. Moreover, the helicoidal arrangement of the protein molecules in the crystal provides a model for 2B-induced host membrane remodeling during HAV infection. IMPORTANCE No structural information is currently available for the 2B protein of any picornavirus despite it being involved in a critical process in viral factory formation: the rearrangement of host intracellular membranes. Here we present the structure of the soluble domain of the 2B protein of hepatitis A virus (HAV). Its arrangement, both in crystals and in solution under physiological conditions, can help to understand its function and sheds some light on the membrane rearrangement process, a putative target of future antiviral drugs. Moreover, this first structure of a picornaviral 2B protein also unveils a closer evolutionary relationship between the hepatovirus and enterovirus genera within the Picornaviridae family.
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14
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Lee W, Watters KE, Troupis AT, Reinen NM, Suchy FP, Moyer KL, Frederick RO, Tonelli M, Aceti DJ, Palmenberg AC, Markley JL. Solution structure of the 2A protease from a common cold agent, human rhinovirus C2, strain W12. PLoS One 2014; 9:e97198. [PMID: 24937088 PMCID: PMC4061012 DOI: 10.1371/journal.pone.0097198] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 04/15/2014] [Indexed: 01/06/2023] Open
Abstract
Human rhinovirus strains differ greatly in their virulence, and this has been correlated with the differing substrate specificity of the respective 2A protease (2Apro). Rhinoviruses use their 2Apro to cleave a spectrum of cellular proteins important to virus replication and anti-host activities. These enzymes share a chymotrypsin-like fold stabilized by a tetra-coordinated zinc ion. The catalytic triad consists of conserved Cys (C105), His (H34), and Asp (D18) residues. We used a semi-automated NMR protocol developed at NMRFAM to determine the solution structure of 2Apro (C105A variant) from an isolate of the clinically important rhinovirus C species (RV-C). The backbone of C2 2Apro superimposed closely (1.41–1.81 Å rmsd) with those of orthologs from RV-A2, coxsackie B4 (CB4), and enterovirus 71 (EV71) having sequence identities between 40% and 60%. Comparison of the structures suggest that the differential functional properties of C2 2Apro stem from its unique surface charge, high proportion of surface aromatics, and sequence surrounding the di-tyrosine flap.
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Affiliation(s)
- Woonghee Lee
- National Magnetic Resonance Facility at Madison, Biochemistry Department, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Kelly E. Watters
- Institute for Molecular Virology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Andrew T. Troupis
- Center for Eukaryotic Structural Genomics, Biochemistry Department, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Nichole M. Reinen
- Center for Eukaryotic Structural Genomics, Biochemistry Department, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Fabian P. Suchy
- Center for Eukaryotic Structural Genomics, Biochemistry Department, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Kylie L. Moyer
- Center for Eukaryotic Structural Genomics, Biochemistry Department, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Ronnie O. Frederick
- Center for Eukaryotic Structural Genomics, Biochemistry Department, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Marco Tonelli
- National Magnetic Resonance Facility at Madison, Biochemistry Department, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - David J. Aceti
- Center for Eukaryotic Structural Genomics, Biochemistry Department, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Ann C. Palmenberg
- Institute for Molecular Virology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - John L. Markley
- National Magnetic Resonance Facility at Madison, Biochemistry Department, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Center for Eukaryotic Structural Genomics, Biochemistry Department, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- * E-mail:
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Wang L, Dong C, Chen DE, Song Z. Visceral pathology of acute systemic injury in newborn mice on the onset of Coxsackie virus infection. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2014; 7:890-904. [PMID: 24696708 PMCID: PMC3971291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Accepted: 02/10/2014] [Indexed: 06/03/2023]
Abstract
Coxsackievirus B (CVB) is a significant pathogen of neonatal diseases with severe systemic involvement and high mortality. Hence, it is essential to develop a CVB-induced acute systemic disease model on newborn mouse and study the injury at the onset phase. In this work, a clinical strain of CVB3, Nancy, and its variant strain, Macocy, were adopted in 24 hour old neonates by oral infection. The pathological changes in the heart, liver and lung tissues were analyzed by pathology assays. In situ end labeling assay for programmed cell death was carried out for liver tissues. The data on fatality and infection rates and pathology scores were analyzed statistically. The genomic sequences of the two strains were aligned. The model represented the manifest clinical syndromes of hepatitis, pneumonia and myocardial injury at the onset phase, in which massive numbers of hepatocytes had undergone programmed cell death. Statistical and pathological analysis indicated that the myocardial injury was mild, whereas the liver and lung were more severe. The fatality rate, infection and pathology of the two CVB strains were the same. Therefore, two nucleotide mutations in the 5' UTR and four amino acid mutations in polyprotein, which did not alter virulence, were shown. By peroral CVB infection of neonatal mice, we developed an acute systemic disease model for studying visceral pathology and systemic disease. At the onset of acute neonatal systemic disease, the hepatitis and pneumonia may be the dominant reason of death, as the injury of liver and lung is more severe than that of heart.
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Affiliation(s)
- Lulu Wang
- Laboratory of Molecular Virus & Cancer, State Key Laboratory of Virology, Wuhan University School of Basic MedicineWuhan 430071, China
| | - Changyuan Dong
- Laboratory of Molecular Virus & Cancer, State Key Laboratory of Virology, Wuhan University School of Basic MedicineWuhan 430071, China
| | - Dong-E Chen
- Department of Epidemiology and Biostatistics, Wuhan University School of Public HealthWuhan 430071, China
| | - Zhen Song
- Laboratory of Molecular Virus & Cancer, State Key Laboratory of Virology, Wuhan University School of Basic MedicineWuhan 430071, China
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An open conformation determined by a structural switch for 2A protease from coxsackievirus A16. Protein Cell 2013; 4:782-92. [PMID: 24026848 DOI: 10.1007/s13238-013-3914-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 09/10/2013] [Indexed: 01/23/2023] Open
Abstract
Coxsackievirus A16 belongs to the family Picornaviridae, and is a major agent of hand-foot-and-mouth disease that infects mostly children, and to date no vaccines or antiviral therapies are available. 2A protease of enterovirus is a nonstructural protein and possesses both self-cleavage activity and the ability to cleave the eukaryotic translation initiation factor 4G. Here we present the crystal structure of coxsackievirus A16 2A protease, which interestingly forms hexamers in crystal as well as in solution. This structure shows an open conformation, with its active site accessible, ready for substrate binding and cleavage activity. In conjunction with a previously reported "closed" state structure of human rhinovirus 2, we were able to develop a detailed hypothesis for the conformational conversion triggered by two "switcher" residues Glu88 and Tyr89 located within the bll2-cII loop. Substrate recognition assays revealed that amino acid residues P1', P2 and P4 are essential for substrate specificity, which was verified by our substrate binding model. In addition, we compared the in vitro cleavage efficiency of 2A proteases from coxsackievirus A16 and enterovirus 71 upon the same substrates by fluorescence resonance energy transfer (FRET), and observed higher protease activity of enterovirus 71 compared to that of coxsackievirus A16. In conclusion, our study shows an open conformation of coxsackievirus A16 2A protease and the underlying mechanisms for conformational conversion and substrate specificity. These new insights should facilitate the future rational design of efficient 2A protease inhibitors.
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17
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Crystal structure of 2A proteinase from hand, foot and mouth disease virus. J Mol Biol 2013; 425:4530-43. [PMID: 23973886 DOI: 10.1016/j.jmb.2013.08.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Revised: 08/07/2013] [Accepted: 08/20/2013] [Indexed: 11/22/2022]
Abstract
EV71 is responsible for several epidemics worldwide; however, the effective antiviral drug is unavailable to date. The 2A proteinase (2A(pro)) of EV71 presents a promising drug target due to its multiple roles in virus replication, inhibition of host protein synthesis and evasion of innate immunity. We determined the crystal structure of EV71 2A(pro) at 1.85Å resolution, revealing that the proteinase maintains a chymotrypsin-like fold. The active site is composed of the catalytic triads C110A, H21 and D39 with the geometry similar to that in other picornaviral 2A(pro), 3C(pro) and serine proteinases. The cI-to-eI2 loop at the N-terminal domain of EV71 2A(pro) adopts a highly stable conformation and contributes to the hydrophilic surface property, which are strikingly different in HRV2 2A(pro) but are similar in CVB4 2A(pro). We identified a hydrophobic motif "LLWL" followed by an acidic motif "DEE" at the C-terminus of EV71 2A(pro). The "LLWL" motif is folded into the β-turn structure that is essential for the positioning of the acidic motif. Our structural and mutagenesis study demonstrated that both the negative charging and the correct positioning of the C-terminus are essential for EV71 replication. Deletion of the "LLWL" motif abrogated the proteolytic activity, indicating that the motif is critical for maintaining the active proteinase conformation. Our findings provide the structural and functional insights into EV71 2A(pro) and establish a framework for structure-based inhibitor design.
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Abstract
The 2A proteinase (2A(pro)) is an enterovirally encoded cysteine protease that plays essential roles in both the processing of viral precursor polyprotein and the hijacking of host cell translation and other processes in the virus life cycle. Crystallographic studies of 2A(pro) from enterovirus 71 (EV71) and its interaction with the substrate are reported here. EV71 2A(pro) was comprised of an N-terminal domain of a four-stranded antiparallel β sheet and a C-terminal domain of a six-stranded antiparallel β barrel with a tightly bound zinc atom. Unlike in other 2A(pro) structures, there is an open cleft across the surface of the protein in an open conformation. As demonstrated by the crystallographic studies and modeling of the complex structure, the open cleft could be fitted with the substrate. On comparison 2A(pro) of EV71 to those of the human rhinovirus 2 and coxsackievirus B4, the open conformation could be closed with a hinge motion in the bII2 and cII β strands. This was supported by molecular dynamic simulation. The structural variation among different 2A(pro) structures indicates a conformational flexibility in the substrate-binding cleft. The open structure provides an accessible framework for the design and development of therapeutics against the viral target.
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19
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Neubauer D, Aumayr M, Gösler I, Skern T. Specificity of human rhinovirus 2A(pro) is determined by combined spatial properties of four cleavage site residues. J Gen Virol 2013; 94:1535-1546. [PMID: 23580429 DOI: 10.1099/vir.0.051201-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The 2A proteinase (2A(pro)) of human rhinoviruses cleaves the virally encoded polyprotein between the C terminus of VP1 and its own N terminus. Poor understanding of the 2A(pro) substrate specificity of this enzyme has hampered progress in developing inhibitors that may serve as antiviral agents. We show here that the 2A(pro) of human rhinovirus (HRV) 1A and 2 (rhinoviruses from genetic group A) cannot self-process at the HRV14 (a genetic group B rhinovirus) cleavage site. When the amino acids in the cleavage site of HRV2 2A(pro) (Ile-Ile-Thr-Thr-Ala*Gly-Pro-Ser-Asp) were singly or doubly replaced with the corresponding HRV14 residues (Asp-Ile-Lys-Ser-Tyr*Gly-Leu-Gly-Pro) at positions from P3 to P2', HRV1A and HRV2 2A(pro) cleavage took place at WT levels. However, when three or more positions of the HRV1A or 2 2A(pro) were substituted (e.g. at P2, P1 and P2'), cleavage in vitro was essentially eliminated. Introduction of the full HRV14 cleavage site into a full-length clone of the HRV1A and transfection of HeLa cells with a transcribed RNA did not give rise to viable virus. In contrast, revertant viruses bearing cysteine at the P1 position or proline at P2' were obtained when an RNA bearing the three inhibitory amino acids was transfected. Reversions in the enzyme affecting substrate specificity were not found in any of the in vivo experiments. Modelling of oligopeptide substrates onto the structure of HRV2 2A(pro) revealed no appreciable differences in residues of HRV2 and HRV14 in the respective substrate binding sites, suggesting that the overall shape of the substrate is important in determining binding efficiency.
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Affiliation(s)
- David Neubauer
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Martina Aumayr
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Irene Gösler
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Tim Skern
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
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20
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Kuo RL, Shih SR. Strategies to develop antivirals against enterovirus 71. Virol J 2013; 10:28. [PMID: 23339605 PMCID: PMC3614426 DOI: 10.1186/1743-422x-10-28] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Accepted: 01/02/2013] [Indexed: 01/08/2023] Open
Abstract
Enterovirus 71 (EV71) is an important human pathogen which may cause severe neurological complications and death in children. The virus caused several outbreaks in the Asia-Pacific region during the past two decades and has been considered a significant public health problem in the post-poliovirus eradication era. Unlike poliovirus, there is no effective vaccine or approved antivirals against EV71. To explore anti-EV71 agents therefore is of vital importance. Several strategies have been employed to develop antivirals based on the molecular characteristics of the virus. Among these, some small molecules that were developed against human rhinoviruses and poliovirus are under evaluation. In this review, we discuss the recent development of such small molecules against EV71, known drug resistance and possible solutions to it, and animal models for evaluating the efficacy of these antivirals. Although further investigation is required for clinical applications of the existing candidates, the molecular mechanisms revealed for the inhibition of EV71 replication can be used for designing new molecules against this virus in the future.
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Affiliation(s)
- Rei-Lin Kuo
- Research Center for Emerging Viral Infections, Chang Gung University, 259 Wen-Hua 1st Road, Kwei-Shan, Taoyuan, Taiwan
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21
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Falah N, Montserret R, Lelogeais V, Schuffenecker I, Lina B, Cortay JC, Violot S. Blocking human enterovirus 71 replication by targeting viral 2A protease. J Antimicrob Chemother 2012; 67:2865-9. [PMID: 22865380 DOI: 10.1093/jac/dks304] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES Human enterovirus 71 (EV-71), a member of the Enterovirus genus, constitutes a major public health issue in the Asia-Pacific region, where it is associated with several severe neurological complications. There is currently no effective vaccine or antiviral against EV-71. The aim of this study was to determine whether the six amino acid peptide LVLQTM, which was previously shown to inhibit human rhinovirus (HRV) 2A protease (2A(pro)) activity in vitro and HRV replication in vivo in mice, could be of more general use against enteroviruses and more particularly against EV-71. METHODS To investigate whether the LVLQTM peptide was a pseudosubstrate of EV-71 2A(pro), a recombinant luciferase containing the LVLQTM sequence was designed so that recognition of this sequence by 2A(pro) led to luciferase activation. Direct interaction between EV-71 2A(pro) and the LVLQTM peptide was further confirmed by isothermal titration calorimetry. We then tested the effects of the peptide on EV-71 2A(pro) cleavage activity and EV-71 replication in HeLa cells. RESULTS We showed that the LVLQTM peptide behaved as an effective substrate analogue of EV-71 2A(pro), which binds into the active site of the protease with a dissociation rate constant of 9.6 μM. Moreover, LVLQTM significantly inhibited eIF4G cleavage activity of 2A(pro) as well as EV-71 replication in HeLa cells. CONCLUSIONS This study demonstrates that the LVLQTM peptide that has previously been shown to inhibit HRV replication is also an effective inhibitor of EV-71 2A(pro) and therefore of EV-71 replication, opening new doors in the development of new antivirals against EV-71.
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Affiliation(s)
- Nisrine Falah
- VirPath, Virologie et Pathologie Humaine, EA4610, Université Lyon 1, Université de Lyon, Faculté de Médecine Lyon-Est, secteur Laennec, Rue Guillaume Paradin, F-69372 Lyon cedex 08, France
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22
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Yun SH, Lee WG, Kim YC, Ju ES, Lim BK, Choi JO, Kim DK, Jeon ES. Antiviral activity of coxsackievirus B3 3C protease inhibitor in experimental murine myocarditis. J Infect Dis 2012; 205:491-7. [PMID: 22207647 DOI: 10.1093/infdis/jir745] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023] Open
Abstract
BACKGROUND We investigated the efficacy of a 3C protease inhibitor (3CPI) in a murine coxsackievirus B3 (CVB3) myocarditis model. CVB3 is a primary cause of viral myocarditis. The CVB3 genome encodes a single polyprotein that undergoes a series of proteolytic events to produce several viral proteins. Most of this proteolysis is catalyzed by the 3C protease (3CP). METHODS AND RESULTS By way of a micro-osmotic pump, each mouse received 50 mM 3CPI in 100 μL of 100% dimethyl sulfoxide (DMSO) during a 72-hour period. On the day of pump implantation, mice (n = 40) were infected intraperitoneally with 10(6) plaque-forming units of CVB3. For the infected controls (n = 50), the pump was filled with 100% DMSO without 3CPI. The 3-week survival rate of 3CPI-treated mice was significantly higher than that of controls (90% vs 22%; P < .01). Myocardial inflammation, viral titers, and viral RNA levels were also reduced significantly in the 3CPI-treated group compared with these measures in the controls. CONCLUSIONS The protein-based drug 3CPI inhibited the activity of 3CP of CVB3, significantly inhibited viral proliferation, and attenuated myocardial inflammations, subsequent fibrosis, and CVB3-induced mortality in vivo. Thus, this CVB3 3CPI has the potential to be a novel therapeutic agent for the treatment of acute viral myocarditis during the viremic phase.
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Affiliation(s)
- Soo-Hyeon Yun
- Division of Cardiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul
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23
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Garriga D, Vives-Adrián L, Buxaderas M, Ferreira-da-Silva F, Almeida B, Macedo-Ribeiro S, Pereira PJB, Verdaguer N. Cloning, purification and preliminary crystallographic studies of the 2AB protein from hepatitis A virus. Acta Crystallogr Sect F Struct Biol Cryst Commun 2011; 67:1224-7. [PMID: 22102033 PMCID: PMC3212368 DOI: 10.1107/s1744309111026261] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Accepted: 07/01/2011] [Indexed: 05/31/2023]
Abstract
The Picornaviridae family contains a large number of human pathogens such as rhinovirus, poliovirus and hepatitis A virus (HAV). Hepatitis A is an infectious disease that causes liver inflammation. It is highly endemic in developing countries with poor sanitation, where infections often occur in children. As in other picornaviruses, the genome of HAV contains one open reading frame encoding a single polyprotein that is subsequently processed by viral proteinases to originate mature viral proteins during and after the translation process. In the polyprotein, the N-terminal P1 region generates the four capsid proteins, while the C-terminal P2 and P3 regions contain the enzymes, precursors and accessory proteins essential for polyprotein processing and virus replication. Here, the first crystals of protein 2AB of HAV are reported. The crystals belonged to space group P4(1) or P4(3), with unit-cell parameters a = b = 90.42, c = 73.43 Å, and contained two molecules in the asymmetric unit. Native and selenomethionine-derivative crystals diffracted to 2.7 and 3.2 Å resolution, respectively.
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Affiliation(s)
- Damià Garriga
- Institut de Biologia Molecular de Barcelona, CSIC, Parc Científic de Barcelona, Baldiri i Reixac 10, 08028 Barcelona, Spain
| | - Laia Vives-Adrián
- Institut de Biologia Molecular de Barcelona, CSIC, Parc Científic de Barcelona, Baldiri i Reixac 10, 08028 Barcelona, Spain
| | - Mònica Buxaderas
- Institut de Biologia Molecular de Barcelona, CSIC, Parc Científic de Barcelona, Baldiri i Reixac 10, 08028 Barcelona, Spain
| | | | - Bruno Almeida
- IBMC – Instituto de Biologia Molecular e Celular, Universidade do Porto, 4150-180 Porto, Portugal
| | - Sandra Macedo-Ribeiro
- IBMC – Instituto de Biologia Molecular e Celular, Universidade do Porto, 4150-180 Porto, Portugal
| | | | - Núria Verdaguer
- Institut de Biologia Molecular de Barcelona, CSIC, Parc Científic de Barcelona, Baldiri i Reixac 10, 08028 Barcelona, Spain
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Norder H, De Palma AM, Selisko B, Costenaro L, Papageorgiou N, Arnan C, Coutard B, Lantez V, De Lamballerie X, Baronti C, Solà M, Tan J, Neyts J, Canard B, Coll M, Gorbalenya AE, Hilgenfeld R. Picornavirus non-structural proteins as targets for new anti-virals with broad activity. Antiviral Res 2011; 89:204-18. [DOI: 10.1016/j.antiviral.2010.12.007] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Revised: 08/23/2010] [Accepted: 12/23/2010] [Indexed: 12/12/2022]
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25
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Houssen WE, Wright SH, Kalverda AP, Thompson GS, Kelly SM, Jaspars M. Solution structure of the leader sequence of the patellamide precursor peptide, PatE1-34. Chembiochem 2011; 11:1867-73. [PMID: 20715266 DOI: 10.1002/cbic.201000305] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The solution structure of the leader sequence of the patellamide precursor peptide was analysed by using CD and determined with NOE-restrained molecular dynamics calculations. This leader sequence is highly conserved in the precursor peptides of some other cyanobactins harbouring heterocycles, and is assumed to play a role in targeting the precursor peptide to the post-translational machinery. The sequence was observed to form an alpha-helix spanning residues 13-28 with a hydrophobic surface on one side of the helix. This hydrophobic surface is proposed to be the site of the initial binding with modifying enzymes.
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Affiliation(s)
- Wael E Houssen
- Marine Biodiscovery Centre, Department of Chemistry, University of Aberdeen, Aberdeen AB24 3UE, Scotland, UK
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26
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Teterina NL, Lauber C, Jensen KS, Levenson EA, Gorbalenya AE, Ehrenfeld E. Identification of tolerated insertion sites in poliovirus non-structural proteins. Virology 2010; 409:1-11. [PMID: 20971490 DOI: 10.1016/j.virol.2010.09.028] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Revised: 08/25/2010] [Accepted: 09/24/2010] [Indexed: 12/20/2022]
Abstract
Insertion of nucleotide sequences encoding "tags" that can be expressed in specific viral proteins during an infection is a useful strategy for purifying viral proteins and their functional complexes from infected cells and/or for visualizing the dynamics of their subcellular location over time. To identify regions in the poliovirus polyprotein that could potentially accommodate insertion of tags, transposon-mediated insertion mutagenesis was applied to the entire nonstructural protein-coding region of the poliovirus genome, followed by selection of genomes capable of generating infectious, viable viruses. This procedure allowed us to identify at least one site in each viral nonstructural protein, except protein 2C, in which a minimum of five amino acids could be inserted. The distribution of these sites is analyzed from the perspective of their protein structural context and from the perspective of virus evolution.
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Teterina NL, Levenson EA, Ehrenfeld E. Viable polioviruses that encode 2A proteins with fluorescent protein tags. J Virol 2010; 84:1477-88. [PMID: 19939919 PMCID: PMC2812313 DOI: 10.1128/jvi.01578-09] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Accepted: 11/12/2009] [Indexed: 11/20/2022] Open
Abstract
The 2A proteins of the Picornaviridae enterovirus genus are small cysteine proteinases that catalyze essential cleavages in the viral polyprotein in cis and in several cellular proteins in trans. In addition, 2A has been implicated in the process of viral RNA replication, independent of its protease functions. We have generated viable polioviruses that encode 2A proteins containing fluorescent protein tag insertions at either of two sites in the 2A protein structure. Viruses containing an insertion of Discosoma sp. red fluorescent protein (DsRed) after residue 144 of 2A, near the C terminus, produced plaques only slightly smaller than wild-type (wt) virus. The polyprotein harboring the 2A-DsRed fusion protein was efficiently and accurately cleaved; fluorescent 2A proteinase retained protease activity in trans and supported translation and replication of viral RNA, both in vitro and in infected cells. Intracellular membrane reorganization to support viral RNA synthesis was indistinguishable from that induced by wt virus. Infected cells exhibited strong red fluorescence from expression of the 2A-DsRed fusion protein, and the progeny virus was stable for three to four passages, after which deletions within the DsRed coding sequence began to accumulate. Confocal microscopic imaging and analysis revealed a portion of 2A-DsRed in punctate foci concentrated in the perinuclear region that colocalized with replication protein 2C. The majority of 2A, however, was associated with an extensive structural matrix throughout the cytoplasm and was not released from infected cells permeabilized with digitonin.
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Affiliation(s)
- Natalya L. Teterina
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Eric A. Levenson
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Ellie Ehrenfeld
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892
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Lin JY, Chen TC, Weng KF, Chang SC, Chen LL, Shih SR. Viral and host proteins involved in picornavirus life cycle. J Biomed Sci 2009; 16:103. [PMID: 19925687 PMCID: PMC2785775 DOI: 10.1186/1423-0127-16-103] [Citation(s) in RCA: 131] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2009] [Accepted: 11/20/2009] [Indexed: 01/11/2023] Open
Abstract
Picornaviruses cause several diseases, not only in humans but also in various animal hosts. For instance, human enteroviruses can cause hand-foot-and-mouth disease, herpangina, myocarditis, acute flaccid paralysis, acute hemorrhagic conjunctivitis, severe neurological complications, including brainstem encephalitis, meningitis and poliomyelitis, and even death. The interaction between the virus and the host is important for viral replication, virulence and pathogenicity. This article reviews studies of the functions of viral and host factors that are involved in the life cycle of picornavirus. The interactions of viral capsid proteins with host cell receptors is discussed first, and the mechanisms by which the viral and host cell factors are involved in viral replication, viral translation and the switch from translation to RNA replication are then addressed. Understanding how cellular proteins interact with viral RNA or viral proteins, as well as the roles of each in viral infection, will provide insights for the design of novel antiviral agents based on these interactions.
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Affiliation(s)
- Jing-Yi Lin
- Research Center for Emerging Viral Infections, Chang Gung University, Tao-Yuan, Taiwan.
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Abstract
Regulation of protein synthesis by viruses occurs at all levels of translation. Even prior to protein synthesis itself, the accessibility of the various open reading frames contained in the viral genome is precisely controlled. Eukaryotic viruses resort to a vast array of strategies to divert the translation machinery in their favor, in particular, at initiation of translation. These strategies are not only designed to circumvent strategies common to cell protein synthesis in eukaryotes, but as revealed more recently, they also aim at modifying or damaging cell factors, the virus having the capacity to multiply in the absence of these factors. In addition to unraveling mechanisms that may constitute new targets in view of controlling virus diseases, viruses constitute incomparably useful tools to gain in-depth knowledge on a multitude of cell pathways.
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Picornaviruses. VIRAL PROTEASES AND ANTIVIRAL PROTEASE INHIBITOR THERAPY 2009. [PMCID: PMC7122559 DOI: 10.1007/978-90-481-2348-3_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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De Palma AM, Vliegen I, De Clercq E, Neyts J. Selective inhibitors of picornavirus replication. Med Res Rev 2008; 28:823-84. [PMID: 18381747 DOI: 10.1002/med.20125] [Citation(s) in RCA: 181] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Picornaviruses cover a large family of pathogens that have a major impact on human but also on veterinary health. Although most infections in man subside mildly or asymptomatically, picornaviruses can also be responsible for severe, potentially life-threatening disease. To date, no therapy has been approved for the treatment of picornavirus infections. However, efforts to develop an antiviral that is effective in treating picornavirus-associated diseases are ongoing. In 2007, Schering-Plough, under license of ViroPharma, completed a phase II clinical trial with Pleconaril, a drug that was originally rejected by the FDA after a New Drug Application in 2001. Rupintrivir, a rhinovirus protease inhibitor developed at Pfizer, reached clinical trials but was recently halted from further development. Finally, Biota's HRV drug BTA-798 is scheduled for phase II trials in 2008. Several key steps in the picornaviral replication cycle, involving structural as well as non-structural proteins, have been identified as valuable targets for inhibition. The current review aims to highlight the most important developments during the past decades in the search for antivirals against picornaviruses.
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Affiliation(s)
- Armando M De Palma
- Rega Institute, Katholieke Universiteit Leuven, Minderbroedersstraat 10, B-3000 Leuven, Belgium
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32
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Maghsoudi N, Khodagholi F, Sadjadi M, Zeinodini M, Sabbaghian M. Purification and partial characterization of coxsackievirus B3 2A protease expressed in Escherichia coli. Int J Biol Macromol 2008; 43:238-44. [PMID: 18590760 DOI: 10.1016/j.ijbiomac.2008.05.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2008] [Revised: 05/27/2008] [Accepted: 05/29/2008] [Indexed: 11/24/2022]
Abstract
Reported here is the overexpression, purification and partial characterization of recombinant coxsakievirus B3 2A protease (CVB3 2Apro) from bacterial cells transformed with a plasmid containing the CVB3 2Apro cDNA sequences. The structural investigation showed that the protein contains mostly beta-strand elements and requires Zn2+ ions as a structural component which appeared to be inhibitory if added exogenously. The purified enzyme activity was optimal at 4 degrees C and had a short half-life at physiological temperature. This feature can be the result of the presence of a high content of beta-structure and also hydrophobic residues in its structure.
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Affiliation(s)
- Nader Maghsoudi
- Neuroscience Research Center, Shahid Beheshti University, M.C., Tehran, Iran.
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Chau DHW, Yuan J, Zhang H, Cheung P, Lim T, Liu Z, Sall A, Yang D. Coxsackievirus B3 proteases 2A and 3C induce apoptotic cell death through mitochondrial injury and cleavage of eIF4GI but not DAP5/p97/NAT1. Apoptosis 2007; 12:513-24. [PMID: 17195095 DOI: 10.1007/s10495-006-0013-0] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2006] [Accepted: 11/09/2006] [Indexed: 02/08/2023]
Abstract
By transfection of Coxsackievirus B3 (CVB3) individual protease gene into HeLa cells, we demonstrated that 2A(pro) and 3C(pro) induced apoptosis through multiple converging pathways. Firstly, both 2A(pro) and 3C(pro) induced caspase-8-mediated activation of caspase-3 and dramatically reduced cell viability. Secondly, they both activated the intrinsic mitochondria-mediated apoptosis pathway leading to cytochrome c release from mitochondria and activation of caspase-9. However, 3C(pro) induced these events via both up-regulation of Bax and cleavage of Bid, and 2A(pro) induced these events via cleavage of Bid only. Nevertheless, neither altered Bcl-2 expression. Thirdly, both proteases induced cell death through cleavage or down regulation of cellular factors for translation and transcription: both 2A(pro) and 3C(pro) cleaved eukaryotic translation initiation factor 4GI but their cleavage products are different, indicating different cleavage sites; further, both 2A(pro) and 3C(pro) down-regulated cyclic AMP responsive element binding protein, a transcription factor, with 2A(pro) exhibiting a stronger effect than 3C(pro). Surprisingly, neither could cleave DAP5/p97/NAT1, a translation regulator, although this cleavage was observed during CVB3 infection and could not be blocked by caspase inhibitor z-VAD-fmk. Taken together, these data suggest that 2A(pro) and 3C(pro) induce apoptosis through both activation of proapoptotic mediators and suppression of translation and transcription.
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Affiliation(s)
- David H W Chau
- Department of Pathology and Laboratory Medicine, The James Hogg iCAPTURE Centre, University of British Columbia, St. Paul's Hospital, Room 166, 1081 Burrard Street, Vancouver, BC, Canada
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Mesters JR, Tan J, Hilgenfeld R. Viral enzymes. Curr Opin Struct Biol 2006; 16:776-86. [PMID: 17085042 PMCID: PMC7127120 DOI: 10.1016/j.sbi.2006.10.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2006] [Revised: 10/16/2006] [Accepted: 10/24/2006] [Indexed: 01/09/2023]
Abstract
Viral genomes show unequalled diversity, ranging from single-stranded DNA to double-stranded RNA. Moreover, viruses can quickly adapt to the host's immune response and drug treatment. Although they tend to make optimal use of the host cell's reservoir of proteins, viruses need to carry some enzymatic functions with them, as they may not be available or accessible in the infected cell. Recently, progress has been made in our structural understanding of viral enzymes involved in all stages of the viral life cycle, which includes entry, hijack, replication and exit stages.
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Affiliation(s)
- Jeroen R Mesters
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, Ratzeburger Allee 160, 23538 Lübeck, Germany
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Sousa C, Schmid EM, Skern T. Defining residues involved in human rhinovirus 2A proteinase substrate recognition. FEBS Lett 2006; 580:5713-7. [PMID: 17007846 DOI: 10.1016/j.febslet.2006.09.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2006] [Accepted: 09/12/2006] [Indexed: 10/24/2022]
Abstract
The 2A proteinase (2A(pro)) of human rhinoviruses (HRVs) initiates proteolytic processing by cleaving between the C-terminus of VP1 and its own N-terminus. It subsequently cleaves the host protein eIF4GI. HRV2 and HRV14 2A(pro) cleave at IITTA *GPSD and DIKSY *GLGP on their respective polyproteins. The HRV2 2A(pro) cleavage site on eIF4GI is TLSTR *GPPR. We show that HRV2 2A(pro) can self-process at the eIF4GI cleavage sequence whereas HRV14 2A(pro) cannot, due to the presence of the arginine residue at P1. The mutations A104C or A104S in HRV14 2A(pro) restored cleavage when arginine was present at P1, although not to wild-type levels. These experiments define residues which determine substrate recognition in rhinoviral 2A(pro).
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Affiliation(s)
- Carla Sousa
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
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