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Policresulen, a novel NS2B/NS3 protease inhibitor, effectively inhibits the replication of DENV2 virus in BHK-21 cells. Acta Pharmacol Sin 2015; 36:1126-36. [PMID: 26279156 DOI: 10.1038/aps.2015.56] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Accepted: 05/08/2015] [Indexed: 12/17/2022] Open
Abstract
AIM Dengue is a severe epidemic disease caused by dengue virus (DENV) infection, for which no effective treatment is available. The protease complex, consisting of nonstructural protein 3 (NS3) and its cofactor NS2B, plays a pivotal role in the replication of DENV, thus may be a potential target for anti-DENV drugs. Here, we report a novel inhibitor of DENV2 NS2B/NS3 protease and its antiviral action. METHODS An enzymatic inhibition assay was used for screening DENV2 NS2B/NS3 inhibitors. Cytotoxicity to BHK-21 cells was assessed with MTT assay. Antiviral activity was evaluated in BHK-21 cells transfected with Rlu-DENV-Rep. The molecular mechanisms of the antiviral action was analyzed using surface plasmon resonance, ultraviolet-visible spectral analysis and differential scanning calorimetry assays, as well as molecular docking analysis combined with site-directed mutagenesis. RESULTS In our in-house library of old drugs (~1000 compounds), a topical hemostatic and antiseptic 2-hydroxy-3,5-bis[(4-hydroxy-2-methyl-5-sulfophenyl)methyl]-4-methyl-benzene-sulfonic acid (policresulen) was found to be a potent inhibitor of DENV2 NS2B/NS3 protease with IC50 of 0.48 μg/mL. Furthermore, policresulen inhibited DENV2 replication in BHK-21 cells with IC50 of 4.99 μg/mL, whereas its IC50 for cytotoxicity to BHK-21 cells was 459.45 μg/mL. Policresulen acted as a competitive inhibitor of the protease, and slightly affected the protease stability. Using biophysical technology-based assays and molecular docking analysis combined with site-directed mutagenesis, we demonstrated that the residues Gln106 and Arg133 of DENV2 NS2B/NS3 protease directly interacted with policresulen via hydrogen bonding. CONCLUSION Policresulen is a potent inhibitor of DENV2 NS2B/NS3 protease that inhibits DENV2 replication in BHK-21 cells. The binding mode of the protease and policresulen provides useful hints for designing new type of inhibitors against the protease.
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Antiviral activities of 15 dengue NS2B-NS3 protease inhibitors using a human cell-based viral quantification assay. Antiviral Res 2015; 118:68-74. [DOI: 10.1016/j.antiviral.2015.03.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 03/19/2015] [Accepted: 03/20/2015] [Indexed: 12/25/2022]
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53
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Yotmanee P, Rungrotmongkol T, Wichapong K, Choi SB, Wahab HA, Kungwan N, Hannongbua S. Binding specificity of polypeptide substrates in NS2B/NS3pro serine protease of dengue virus type 2: A molecular dynamics Study. J Mol Graph Model 2015; 60:24-33. [PMID: 26086900 DOI: 10.1016/j.jmgm.2015.05.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 05/14/2015] [Accepted: 05/15/2015] [Indexed: 02/05/2023]
Abstract
The pathogenic dengue virus (DV) is a growing global threat, particularly in South East Asia, for which there is no specific treatment available. The virus possesses a two-component (NS2B/NS3) serine protease that cleaves the viral precursor proteins. Here, we performed molecular dynamics simulations of the NS2B/NS3 protease complexes with six peptide substrates (capsid, intNS3, 2A/2B, 4B/5, 3/4A and 2B/3 containing the proteolytic site between P(1) and P(1)' subsites) of DV type 2 to compare the specificity of the protein-substrate binding recognition. Although all substrates were in the active conformation for cleavage reaction by NS2B/NS3 protease, their binding strength was somewhat different. The simulated results of intermolecular hydrogen bonds and decomposition energies suggested that among the ten substrate residues (P(5)-P(5)') the P(1) and P(2) subsites play a major role in the binding with the focused protease. The arginine residue at these two subsites was found to be specific preferential binding at the active site with a stabilization energy of <-10 kcal mol(-1). Besides, the P(3), P(1)', P(2)' and P(4)' subsites showed a less contribution in binding interaction (<-2 kcal mol(-1)). The catalytic water was detected nearby the carbonyl oxygen of the P(1) reacting center of the capsid, intNS3, 2A/2B and 4B/5 peptides. These results led to the order of absolute binding free energy (ΔGbind) between these substrates and the NS2B/NS3 protease ranked as capsid>intNS3>2A/2B>4B/5>3/4A>2B/3 in a relative correspondence with previous experimentally derived values.
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Affiliation(s)
- Pathumwadee Yotmanee
- Department of Chemistry, Faculty of Science, Ramkhamhaeng University, Bangkok 10240, Thailand; Computational Chemistry Unit Cell, Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Thanyada Rungrotmongkol
- Ph.D. Program in Bioinformatics and Computational Biology, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand; Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Kanin Wichapong
- Computational Chemistry Unit Cell, Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Sy Bing Choi
- School of Pharmaceutical Sciences, Universiti Sains Malaysia, Gelugor 11800, Pulau Pinang, Malaysia; Natural Product and Drug Discovery Centre, Malaysian Institutes of Pharmaceuticals and Nutraceuticals, National Institutes of Biotechnology Malaysia, Ministry of Science, Technology and Innovation, Block 5-A, Halaman Bukit Gambir, 11700, Penang, Malaysia
| | - Habibah A Wahab
- School of Pharmaceutical Sciences, Universiti Sains Malaysia, Gelugor 11800, Pulau Pinang, Malaysia; Natural Product and Drug Discovery Centre, Malaysian Institutes of Pharmaceuticals and Nutraceuticals, National Institutes of Biotechnology Malaysia, Ministry of Science, Technology and Innovation, Block 5-A, Halaman Bukit Gambir, 11700, Penang, Malaysia.
| | - Nawee Kungwan
- Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Supot Hannongbua
- Computational Chemistry Unit Cell, Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
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Li L, Basavannacharya C, Chan KWK, Shang L, Vasudevan SG, Yin Z. Structure-guided Discovery of a Novel Non-peptide Inhibitor of Dengue Virus NS2B-NS3 Protease. Chem Biol Drug Des 2015; 86:255-64. [DOI: 10.1111/cbdd.12500] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 12/15/2014] [Accepted: 12/17/2014] [Indexed: 12/19/2022]
Affiliation(s)
- Linfeng Li
- College of Pharmacy; State Key Laboratory of Elemento-Organic Chemistry; Nankai University; Tianjin 300071 China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin); Tianjin 300071 China
| | - Chandrakala Basavannacharya
- Duke-NUS Graduate Medical School; Program in Emerging Infectious Diseases; 8 College Road Singapore 169857 Singapore
| | - Kitti Wing Ki Chan
- Duke-NUS Graduate Medical School; Program in Emerging Infectious Diseases; 8 College Road Singapore 169857 Singapore
| | - Luqing Shang
- College of Pharmacy; State Key Laboratory of Elemento-Organic Chemistry; Nankai University; Tianjin 300071 China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin); Tianjin 300071 China
| | - Subhash G. Vasudevan
- Duke-NUS Graduate Medical School; Program in Emerging Infectious Diseases; 8 College Road Singapore 169857 Singapore
| | - Zheng Yin
- College of Pharmacy; State Key Laboratory of Elemento-Organic Chemistry; Nankai University; Tianjin 300071 China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin); Tianjin 300071 China
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55
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Li Y, Tian P. Contemplating 3-Hydroxypropionic Acid Biosynthesis in Klebsiella pneumoniae. Indian J Microbiol 2015; 55:131-9. [PMID: 25805899 DOI: 10.1007/s12088-015-0513-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 01/09/2015] [Indexed: 11/30/2022] Open
Abstract
3-Hydroxypropionic acid (3-HP) is a commercially valuable platform chemical from which an array of C3 compounds can be generated. Klebsiella pneumoniae has been considered a promising species for biological production of 3-HP. Despite a wealth of reports related to 3-HP biosynthesis in K. pneumoniae, its commercialization is still in infancy. The major hurdle hindering 3-HP overproduction lies in the poor understanding of glycerol dissimilation in K. pneumoniae. To surmount this problem, this review aims to portray a picture of 3-HP biosynthesis, involving 3-HP-synthesizing strains, biochemical attributes, metabolic pathways and key enzymes. Inspired by the state-of-the-art advances in metabolic engineering and synthetic biology, here we advocate protocols for overproducing 3-HP in K. pneumoniae. These protocols range from cofactor regeneration, alleviation of metabolite toxicity, genome editing, remodeling of transport system, to carbon flux partition via logic gate. The feasibility for these protocols was also discussed.
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Affiliation(s)
- Ying Li
- Beijing Key Lab of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029 People's Republic of China
| | - Pingfang Tian
- Beijing Key Lab of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029 People's Republic of China
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56
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Bhakat S, Karubiu W, Jayaprakash V, Soliman ME. A perspective on targeting non-structural proteins to combat neglected tropical diseases: Dengue, West Nile and Chikungunya viruses. Eur J Med Chem 2014; 87:677-702. [DOI: 10.1016/j.ejmech.2014.10.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2014] [Revised: 09/29/2014] [Accepted: 10/04/2014] [Indexed: 01/07/2023]
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Liu H, Wu R, Sun Y, Ye Y, Chen J, Luo X, Shen X, Liu H. Identification of novel thiadiazoloacrylamide analogues as inhibitors of dengue-2 virus NS2B/NS3 protease. Bioorg Med Chem 2014; 22:6344-52. [DOI: 10.1016/j.bmc.2014.09.057] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Revised: 09/24/2014] [Accepted: 09/26/2014] [Indexed: 10/24/2022]
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58
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Nitsche C, Holloway S, Schirmeister T, Klein CD. Biochemistry and medicinal chemistry of the dengue virus protease. Chem Rev 2014; 114:11348-81. [PMID: 25268322 DOI: 10.1021/cr500233q] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Christoph Nitsche
- Medicinal Chemistry, Institute of Pharmacy and Molecular Biotechnology IPMB, Heidelberg University , Im Neuenheimer Feld 364, D-69120 Heidelberg, Germany
| | - Steven Holloway
- Institut für Pharmazie und Biochemie, Johannes Gutenberg-Universität Mainz , Staudingerweg 5, D-55128 Mainz, Germany
| | - Tanja Schirmeister
- Institut für Pharmazie und Biochemie, Johannes Gutenberg-Universität Mainz , Staudingerweg 5, D-55128 Mainz, Germany
| | - Christian D Klein
- Medicinal Chemistry, Institute of Pharmacy and Molecular Biotechnology IPMB, Heidelberg University , Im Neuenheimer Feld 364, D-69120 Heidelberg, Germany
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59
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Behnam MAM, Nitsche C, Vechi SM, Klein CD. C-terminal residue optimization and fragment merging: discovery of a potent Peptide-hybrid inhibitor of dengue protease. ACS Med Chem Lett 2014; 5:1037-42. [PMID: 25221663 DOI: 10.1021/ml500245v] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Accepted: 07/18/2014] [Indexed: 01/22/2023] Open
Abstract
Dengue virus protease is a promising target for the development of antiviral drugs. We describe here a two-step rational optimization that led to the discovery of the potent inhibitor 35 with nanomolar binding affinity at dengue protease serotype 2 (IC50 = 0.6 μM, K i = 0.4 μM). First, a large number of natural and non-natural amino acids were screened at the C-terminal position of the previously reported, canonical peptide sequence (Cap-Arg-Lys-Nle-NH2). Compared to the reference compound 1 (Bz-Arg-Lys-Nle-NH2, IC50 = 13.3 μM), a 4-fold higher inhibitory potential was observed with the incorporation of a C-terminal phenylglycine (compound 9, IC50 = 3.3 μM). Second, we applied fragment merging of 9 with the previously reported thiazolidinedione peptide hybrid 33 (IC50 = 2.5 μM). This approach led to the fusion of two inhibitor-fragments with micromolar affinity into a 20-fold more potent, competitive inhibitor of dengue protease.
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Affiliation(s)
- Mira A. M. Behnam
- Medicinal
Chemistry, Institute of Pharmacy and Molecular Biotechnology IPMB, Heidelberg University, Im Neuenheimer Feld 364, 69120 Heidelberg, Germany
| | - Christoph Nitsche
- Medicinal
Chemistry, Institute of Pharmacy and Molecular Biotechnology IPMB, Heidelberg University, Im Neuenheimer Feld 364, 69120 Heidelberg, Germany
| | - Sérgio M. Vechi
- Medicinal
Chemistry, Institute of Pharmacy and Molecular Biotechnology IPMB, Heidelberg University, Im Neuenheimer Feld 364, 69120 Heidelberg, Germany
- Federal University of Alagoas (UFAL), Campus Arapiraca, NCEx, 57309-005 Arapiraca, Alagoas, Brazil
| | - Christian D. Klein
- Medicinal
Chemistry, Institute of Pharmacy and Molecular Biotechnology IPMB, Heidelberg University, Im Neuenheimer Feld 364, 69120 Heidelberg, Germany
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60
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Chen WN, Loscha KV, Nitsche C, Graham B, Otting G. The dengue virus NS2B-NS3 protease retains the closed conformation in the complex with BPTI. FEBS Lett 2014; 588:2206-11. [PMID: 24859037 DOI: 10.1016/j.febslet.2014.05.018] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 04/16/2014] [Accepted: 05/07/2014] [Indexed: 12/19/2022]
Abstract
The C-terminal β-hairpin of NS2B (NS2Bc) in the dengue virus NS2B-NS3 protease is required for full enzymatic activity. In crystal structures without inhibitor and in the complex with bovine pancreatic trypsin inhibitor (BPTI), NS2Bc is displaced from the active site. In contrast, nuclear magnetic resonance (NMR) studies in solution only ever showed NS2Bc in the enzymatically active closed conformation. Here we demonstrate by pseudocontact shifts from a lanthanide tag that NS2Bc remains in the closed conformation also in the complex with BPTI. Therefore, the closed conformation is the best template for drug discovery.
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Affiliation(s)
- Wan-Na Chen
- Australian National University, Research School of Chemistry, Canberra, ACT 0200, Australia
| | - Karin V Loscha
- Australian National University, Research School of Chemistry, Canberra, ACT 0200, Australia
| | - Christoph Nitsche
- Medicinal Chemistry, Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Im Neuenheimer Feld 364, 69120 Heidelberg, Germany
| | - Bim Graham
- Medicinal Chemistry and Drug Action, Monash Institute of Pharmaceutical Sciences, Parkville, VIC 3052, Australia
| | - Gottfried Otting
- Australian National University, Research School of Chemistry, Canberra, ACT 0200, Australia.
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61
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de la Cruz L, Chen WN, Graham B, Otting G. Binding mode of the activity-modulating C-terminal segment of NS2B to NS3 in the dengue virus NS2B-NS3 protease. FEBS J 2014; 281:1517-33. [PMID: 24472363 DOI: 10.1111/febs.12729] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 01/21/2014] [Accepted: 01/24/2014] [Indexed: 12/16/2022]
Abstract
The two-component dengue virus NS2B-NS3 protease (NS2B-NS3pro) is an established drug target but inhibitor design is hampered by uncertainties about its 3D structure in solution. Crystal structures reported very different conformations for the functionally important C-terminal segment of the NS2B cofactor (NS2Bc), indicating open and closed conformations in the absence and presence of inhibitors, respectively. An earlier NMR study in solution indicated that a closed state is the preferred conformation in the absence of an artificial linker engineered between NS2B and NS3pro. To obtain direct structural information on the fold of unlinked NS2B-NS3pro in solution, we tagged NS3pro with paramagnetic tags and measured pseudocontact shifts by NMR to position NS2Bc relative to NS3pro. NS2Bc was found to bind to NS3pro in the same way as reported in a previously published model and crystal structure of the closed state. The structure is destabilized, however, by high ionic strength and basic pH, showing the importance of electrostatic forces to tie NS2Bc to NS3pro. Narrow NMR signals previously thought to represent the open state are associated with protein degradation. In conclusion, the closed conformation of the NS2B-NS3 protease is the best model for structure-guided drug design.
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Affiliation(s)
- Laura de la Cruz
- Research School of Chemistry, Australian National University, Canberra, Australia
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62
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Ang MJY, Li Z, Lim HA, Ng FM, Then SW, Wee JLK, Joy J, Hill J, Chia CSB. A P2 and P3 substrate specificity comparison between the Murray Valley encephalitis and West Nile virus NS2B/NS3 protease using C-terminal agmatine dipeptides. Peptides 2014; 52:49-52. [PMID: 24333681 DOI: 10.1016/j.peptides.2013.12.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2013] [Revised: 12/02/2013] [Accepted: 12/02/2013] [Indexed: 12/26/2022]
Abstract
The Murray Valley encephalitis virus (MVEV) and the West Nile virus (WNV) are mosquito-borne single-stranded RNA Flaviviruses responsible for many cases of viral encephalitis and deaths worldwide. The former is endemic in north Australia and Papua New Guinea while the latter has spread to different parts of the world and was responsible for a recent North American outbreak in 2012, resulting in 243 fatalities. There is currently no approved vaccines or drugs against MVEV and WNV viral infections. A plausible drug target is the viral non-structural NS2B/NS3 protease due to its role in viral replication. This trypsin-like serine protease recognizes and cleaves viral polyproteins at the C-terminal end of an arginine residue, opening an avenue for the development of peptide-based antivirals. This communication compares the P2 and P3 residue preferences of the MVEV and WNV NS2B/NS3 proteases using a series of C-terminal agmatine dipeptides. Our results revealed that both viral enzymes were highly specific toward lysines at the P2 and P3 positions, suggesting that a peptidomimetic viral protease inhibitor developed against one virus should also be active against the other.
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Affiliation(s)
- Melgious Jin Yan Ang
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore
| | - Zhitao Li
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore
| | - Huichang Annie Lim
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore
| | - Fui Mee Ng
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore
| | - Siew Wen Then
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore
| | - John Liang Kuan Wee
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore
| | - Joma Joy
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore
| | - Jeffrey Hill
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore
| | - C S Brian Chia
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore.
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63
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Recent Advances in Targeting Dengue and West Nile Virus Proteases Using Small Molecule Inhibitors. TOPICS IN MEDICINAL CHEMISTRY 2014. [DOI: 10.1007/7355_2014_46] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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64
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Nguyen TTH, Lee S, Wang HK, Chen HY, Wu YT, Lin SC, Kim DW, Kim D. In vitro evaluation of novel inhibitors against the NS2B-NS3 protease of dengue fever virus type 4. Molecules 2013; 18:15600-12. [PMID: 24352016 PMCID: PMC6269914 DOI: 10.3390/molecules181215600] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Revised: 12/02/2013] [Accepted: 12/11/2013] [Indexed: 12/16/2022] Open
Abstract
The discovery of potent therapeutic compounds against dengue virus is urgently needed. The NS2B-NS3 protease (NS2B-NS3pro) of dengue fever virus carries out all enzymatic activities needed for polyprotein processing and is considered to be amenable to antiviral inhibition by analogy. Virtual screening of 300,000 compounds using Autodock 3 on the GVSS platform was conducted to identify novel inhibitors against the NS2B-NS3pro. Thirty-six compounds were selected for in vitro assay against NS2B-NS3pro expressed in Pichia pastoris. Seven novel compounds were identified as inhibitors with IC50 values of 3.9 ± 0.6-86.7 ± 3.6 μM. Three strong NS2B-NS3pro inhibitors were further confirmed as competitive inhibitors with Ki values of 4.0 ± 0.4, 4.9 ± 0.3, and 3.4 ± 0.1 μM, respectively. Hydrophobic and hydrogen bond interactions between amino acid residues in the NS3pro active site with inhibition compounds were also identified.
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Affiliation(s)
- Thi Thanh Hanh Nguyen
- Department of Biotechnology and Bioengineering, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, Korea; E-Mails: (T.T.H.N.); (S.L.)
- Research Institute of Bio Food Industry, The Green Bio Research Complex, Seoul National University, San 967-2 Shin-ri, Pyeongchang-gun, Gangwon-do 232-916, Korea
| | - Sun Lee
- Department of Biotechnology and Bioengineering, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, Korea; E-Mails: (T.T.H.N.); (S.L.)
| | - Hsi-Kai Wang
- Research Center for Information Technology Innovation, Academia Sinica, 128, Sec.2, Academia Rd., Nankang, Taipei 11529, Taiwan; E-Mails: (H.-K.W.); (H.-Y.C.); (S.C.L.)
| | - Hsin-Yen Chen
- Research Center for Information Technology Innovation, Academia Sinica, 128, Sec.2, Academia Rd., Nankang, Taipei 11529, Taiwan; E-Mails: (H.-K.W.); (H.-Y.C.); (S.C.L.)
| | - Ying-Ta Wu
- Genomics Research Center, Academia Sinica, 128, Sec.2, Academia Rd., Nankang, Taipei 11529, Taiwan; E-Mail:
| | - Simon C. Lin
- Research Center for Information Technology Innovation, Academia Sinica, 128, Sec.2, Academia Rd., Nankang, Taipei 11529, Taiwan; E-Mails: (H.-K.W.); (H.-Y.C.); (S.C.L.)
| | - Do-Won Kim
- Department of Physics, Gangneung-Wonju National University, Gangneung 210-702, Korea; E-Mail:
| | - Doman Kim
- Department of Biotechnology and Bioengineering, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, Korea; E-Mails: (T.T.H.N.); (S.L.)
- Research Institute of Bio Food Industry, The Green Bio Research Complex, Seoul National University, San 967-2 Shin-ri, Pyeongchang-gun, Gangwon-do 232-916, Korea
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Discovery and SAR studies of methionine–proline anilides as dengue virus NS2B-NS3 protease inhibitors. Bioorg Med Chem Lett 2013; 23:6549-54. [DOI: 10.1016/j.bmcl.2013.10.071] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 10/10/2013] [Accepted: 10/31/2013] [Indexed: 01/05/2023]
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66
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The flavivirus protease as a target for drug discovery. Virol Sin 2013; 28:326-36. [PMID: 24242363 DOI: 10.1007/s12250-013-3390-x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 11/01/2013] [Indexed: 01/27/2023] Open
Abstract
Many flaviviruses are significant human pathogens causing considerable disease burdens, including encephalitis and hemorrhagic fever, in the regions in which they are endemic. A paucity of treatments for flaviviral infections has driven interest in drug development targeting proteins essential to flavivirus replication, such as the viral protease. During viral replication, the flavivirus genome is translated as a single polyprotein precursor, which must be cleaved into individual proteins by a complex of the viral protease, NS3, and its cofactor, NS2B. Because this cleavage is an obligate step of the viral life-cycle, the flavivirus protease is an attractive target for antiviral drug development. In this review, we will survey recent drug development studies targeting the NS3 active site, as well as studies targeting an NS2B/NS3 interaction site determined from flavivirus protease crystal structures.
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67
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Tambunan USF, Pratomo H, Parikesit AA. Modification of Kampmann A5 as Potential Fusion Inhibitor of Dengue Virus using Molecular Docking and Molecular Dynamics Approach. JOURNAL OF MEDICAL SCIENCES 2013. [DOI: 10.3923/jms.2013.621.634] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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68
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Nitsche C, Schreier VN, Behnam MAM, Kumar A, Bartenschlager R, Klein CD. Thiazolidinone-peptide hybrids as dengue virus protease inhibitors with antiviral activity in cell culture. J Med Chem 2013; 56:8389-403. [PMID: 24083834 DOI: 10.1021/jm400828u] [Citation(s) in RCA: 103] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The protease of dengue virus is a promising target for antiviral drug discovery. We here report a new generation of peptide-hybrid inhibitors of dengue protease that incorporate N-substituted 5-arylidenethiazolidinone heterocycles (rhodanines and thiazolidinediones) as N-terminal capping groups of the peptide moiety. The compounds were extensively characterized with respect to inhibition of various proteases, inhibition mechanisms, membrane permeability, antiviral activity, and cytotoxicity in cell culture. A sulfur/oxygen exchange in position 2 of the capping heterocycle (thiazolidinedione-capped vs rhodanine-capped peptide hybrids) has a significant effect on these properties and activities. The most promising in vitro affinities were observed for thiazolidinedione-based peptide hybrids containing hydrophobic groups with Ki values between 1.5 and 1.8 μM and competitive inhibition mechanisms. Rhodanine-capped peptide hybrids with hydrophobic substituents have, in correlation with their membrane permeability, a more pronounced antiviral activity in cell culture than the thiazolidinediones.
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Affiliation(s)
- Christoph Nitsche
- Medicinal Chemistry, Institute of Pharmacy and Molecular Biotechnology IPMB, Heidelberg University , Im Neuenheimer Feld 364, 69120 Heidelberg, Germany
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69
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A novel dengue virus inhibitor, BP13944, discovered by high-throughput screening with dengue virus replicon cells selects for resistance in the viral NS2B/NS3 protease. Antimicrob Agents Chemother 2013; 58:110-9. [PMID: 24145533 DOI: 10.1128/aac.01281-13] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Dengue virus (DENV) causes disease globally, resulting in an estimated 25 to 100 million new infections per year. No effective DENV vaccine is available, and the current treatment is only supportive. Thus, there is an urgent need to develop therapeutic agents to cure this epidemic disease. In the present study, we identified a potential small-molecule inhibitor, BP13944, via high-throughput screening (HTS) of 60,000 compounds using a stable cell line harboring an efficient luciferase replicon of DENV serotype 2 (DENV-2). BP13944 reduced the expression of the DENV replicon reporter in cells, showing a 50% effective concentration (EC50) of 1.03 ± 0.09 μM. Without detectable cytotoxicity, the compound inhibited replication or viral RNA synthesis in all four serotypes of DENV but not in Japanese encephalitis virus (JEV). Sequencing analyses of several individual clones derived from BP13944-resistant RNAs purified from cells harboring the DENV-2 replicon revealed a consensus amino acid substitution (E66G) in the region of the NS3 protease domain. Introduction of E66G into the DENV replicon, an infectious DENV cDNA clone, and recombinant NS2B/NS3 protease constructs conferred 15.2-, 17.2-, and 3.1-fold resistance to BP13944, respectively. Our results identify an effective small-molecule inhibitor, BP13944, which likely targets the DENV NS3 protease. BP13944 could be considered part of a more effective treatment regime for inhibiting DENV in the future.
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70
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Lim SP, Wang QY, Noble CG, Chen YL, Dong H, Zou B, Yokokawa F, Nilar S, Smith P, Beer D, Lescar J, Shi PY. Ten years of dengue drug discovery: progress and prospects. Antiviral Res 2013; 100:500-19. [PMID: 24076358 DOI: 10.1016/j.antiviral.2013.09.013] [Citation(s) in RCA: 263] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 09/07/2013] [Accepted: 09/15/2013] [Indexed: 01/26/2023]
Abstract
To combat neglected diseases, the Novartis Institute of Tropical Diseases (NITD) was founded in 2002 through private-public funding from Novartis and the Singapore Economic Development Board. One of NITD's missions is to develop antivirals for dengue virus (DENV), the most prevalent mosquito-borne viral pathogen. Neither vaccine nor antiviral is currently available for DENV. Here we review the progress in dengue drug discovery made at NITD as well as the major discoveries made by academia and other companies. Four strategies have been pursued to identify inhibitors of DENV through targeting both viral and host proteins: (i) HTS (high-throughput screening) using virus replication assays; (ii) HTS using viral enzyme assays; (iii) structure-based in silico docking and rational design; (iv) repurposing hepatitis C virus inhibitors for DENV. Along the developmental process from hit finding to clinical candidate, many inhibitors did not advance beyond the stage of hit-to-lead optimization, due to their poor selectivity, physiochemical or pharmacokinetic properties. Only a few compounds showed efficacy in the AG129 DENV mouse model. Two nucleoside analogs, NITD-008 and Balapiravir, entered preclinical animal safety study and clinic trial, but both were terminated due to toxicity and lack of potency, respectively. Celgosivir, a host alpha-glucosidase inhibitor, is currently under clinical trial; its clinical efficacy remains to be determined. The knowledge accumulated during the past decade has provided a better rationale for ongoing dengue drug discovery. Though challenging, we are optimistic that this continuous, concerted effort will lead to an effective dengue therapy.
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Affiliation(s)
- Siew Pheng Lim
- Novartis Institute for Tropical Diseases, 10 Biopolis Road, 05-01 Chromos, Singapore 138670, Singapore
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71
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Heh CH, Othman R, Buckle MJC, Sharifuddin Y, Yusof R, Rahman NA. Rational Discovery of Dengue Type 2 Non-Competitive Inhibitors. Chem Biol Drug Des 2013; 82:1-11. [DOI: 10.1111/cbdd.12122] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 01/16/2013] [Accepted: 02/12/2013] [Indexed: 12/14/2022]
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72
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Prusis P, Junaid M, Petrovska R, Yahorava S, Yahorau A, Katzenmeier G, Lapins M, Wikberg JES. Design and evaluation of substrate-based octapeptide and non substrate-based tetrapeptide inhibitors of dengue virus NS2B-NS3 proteases. Biochem Biophys Res Commun 2013; 434:767-72. [PMID: 23587903 DOI: 10.1016/j.bbrc.2013.03.139] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Accepted: 03/29/2013] [Indexed: 12/13/2022]
Abstract
A series of 45 peptide inhibitors was designed, synthesized, and evaluated against the NS2B-NS3 proteases of the four subtypes of dengue virus, DEN-1-4. The design was based on proteochemometric models for Michaelis (Km) and cleavage rate constants (kcat) of protease substrates. This led first to octapeptides showing submicromolar or low micromolar inhibitory activities on the four proteases. Stepwise removal of cationic substrate non-prime side residues and variations in the prime side sequence resulted finally in an uncharged tetrapeptide, WYCW-NH2, with inhibitory Ki values of 4.2, 4.8, 24.4, and 11.2 μM for the DEN-1-4 proteases, respectively. Analysis of the inhibition data by proteochemometric modeling suggested the possibility for different binding poses of the shortened peptides compared to the octapeptides, which was supported by results of docking of WYCW-NH2 into the X-ray structure of DEN-3 protease.
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Affiliation(s)
- Peteris Prusis
- Department of Pharmaceutical Biosciences, Division of Pharmacology, Uppsala University, 75124 Uppsala, Sweden
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73
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Dengue virus therapeutic intervention strategies based on viral, vector and host factors involved in disease pathogenesis. Pharmacol Ther 2013; 137:266-82. [DOI: 10.1016/j.pharmthera.2012.10.007] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Accepted: 10/15/2012] [Indexed: 12/27/2022]
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74
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Nitsche C, Klein CD. Fluorimetric and HPLC-based dengue virus protease assays using a FRET substrate. Methods Mol Biol 2013; 1030:221-236. [PMID: 23821272 DOI: 10.1007/978-1-62703-484-5_18] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The number of dengue virus infections is increasing and the dengue NS2B-NS3 protease is considered a promising target for the development of antiviral therapies. Therefore, reliable and fast screening systems are needed for the discovery of new lead structures. In this chapter, we describe two dengue virus protease assays based on an internally quenched, high-affinity Förster resonance energy transfer (FRET) substrate (Km = 105 μM). A fluorimetric assay using a microtiter fluorescence plate reader can be used for high-throughput screening of a large number of compounds. Alternatively, an HPLC-based assay with fluorescence detection can be applied to confirm the compound hits and to avoid false-positive results that may arise due to the inner filter effect of some compounds.
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Affiliation(s)
- Christoph Nitsche
- Medicinal Chemistry, Institute of Pharmacy and Molecular Biotechnology (IPMB), Heidelberg University, Heidelberg, Germany
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75
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Protegrin-1 inhibits dengue NS2B-NS3 serine protease and viral replication in MK2 cells. J Biomed Biotechnol 2012; 2012:251482. [PMID: 23093838 PMCID: PMC3470887 DOI: 10.1155/2012/251482] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Revised: 08/31/2012] [Accepted: 09/02/2012] [Indexed: 11/17/2022] Open
Abstract
Dengue diseases have an economic as well as social burden worldwide. In this study, the antiviral activity of protegrin-1 (PG-1, RGGRLCYCRRRFCVCVGR) peptide towards dengue NS2B-NS3pro and viral replication in Rhesus monkey kidney (MK2) cells was investigated. The peptide PG-1 was synthesized by solid-phase peptide synthesis, and disulphide bonds formation followed by peptide purification was confirmed by LC-MS and RPHPLC. Dengue NS2B-NS3pro was produced as a single-chain recombinant protein in E. coli. The NS2B-NS3pro assay was carried out by measuring the florescence emission of catalyzed substrate. Real-time PCR was used to evaluate the inhibition potential of PG-1 towards dengue serotype-2 (DENV-2) replication in MK2 cells. The results showed that PG-1 inhibited dengue NS2B-NS3pro at IC(50) of 11.7 μM. The graded concentrations of PG-1 at nontoxic range were able to reduce viral replication significantly (P < 0.001) at 24, 48, and 72 hrs after viral infection. However, the percentage of inhibition was significantly (P < 0.01) higher at 24 hrs compared to 48 and 72 hrs. These data show promising therapeutic potential of PG-1 against dengue infection, hence it warrants further analysis and improvement of the peptide features as a prospective starting point for consideration in designing attractive dengue virus inhibitors.
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76
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Ede NJ, Hill J, Joy JK, Ede AM, Koppens ML. Solid-phase synthesis and screening of a library of C-terminal arginine peptide aldehydes against Murray Valley encephalitis virus protease. J Pept Sci 2012; 18:661-8. [PMID: 22991186 PMCID: PMC7167811 DOI: 10.1002/psc.2450] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Revised: 07/13/2012] [Accepted: 08/05/2012] [Indexed: 02/02/2023]
Abstract
Murray Valley encephalitis virus is a member of the flavivirus group, a large family of single‐stranded RNA viruses, which cause serious disease in all regions of the world. Unfortunately, no suitable antivirals are available, and there are commercial vaccines for only three flaviviruses. The solid‐phase synthesis of a library of 400 C‐terminal arginine peptide aldehydes and their screening against Murray Valley encephalitis virus protease are demonstrated. The library was utilised to elucidate several tripeptide sequences that can be used as inhibitors in further SAR studies. Copyright © 2012 European Peptide Society and John Wiley & Sons, Ltd.
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Affiliation(s)
- Nicholas J Ede
- Consegna Group Ltd, 7/21 Northumberland St, Collingwood 3066, Victoria, Australia.
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77
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Structural biology of dengue virus enzymes: towards rational design of therapeutics. Antiviral Res 2012; 96:115-26. [PMID: 22995600 DOI: 10.1016/j.antiviral.2012.09.007] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Revised: 09/03/2012] [Accepted: 09/07/2012] [Indexed: 02/07/2023]
Abstract
Development of anti-dengue therapy represents an urgent un-met medical need. Towards antiviral therapy, recent advances in crystal structures of DENV enzymes have led to the possibility of structure-based rational design of inhibitors for anti-dengue therapy. These include (i) the structure of the 'active' form of the DENV protease in complex with a peptide substrate; (ii) the structure of DENV methyltransferase bound to an inhibitor that selectively suppresses viral methyltransferase, but not human methyltransferases; (iii) the structure of DENV RNA-dependent RNA polymerase in complex with a small-molecule compound. This review summarizes the structural biology of these three key enzymes (protease, methyltransferase, and polymerase) that are essential for DENV replication. The new structural information has provided new avenues for development of anti-dengue therapy.
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78
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Deng J, Li N, Liu H, Zuo Z, Liew OW, Xu W, Chen G, Tong X, Tang W, Zhu J, Zuo J, Jiang H, Yang CG, Li J, Zhu W. Discovery of Novel Small Molecule Inhibitors of Dengue Viral NS2B-NS3 Protease Using Virtual Screening and Scaffold Hopping. J Med Chem 2012; 55:6278-93. [DOI: 10.1021/jm300146f] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Jing Deng
- Shanghai Key Laboratory of New
Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Mei Long Road, Shanghai
200237, China
| | - Ning Li
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555
Zu Chong Zhi Road, Shanghai 201203, China
| | - Hongchuan Liu
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555
Zu Chong Zhi Road, Shanghai 201203, China
| | - Zhili Zuo
- Centre for Biomedical and Life
Sciences, Singapore Polytechnic, 500 Dover
Road, Singapore 139651
| | - Oi Wah Liew
- Cardiovascular Research Institute,
Yong Loo Lin School of Medicine, National University of Singapore, 14 Medical Drive, Singapore 117599
| | - Weijun Xu
- Centre for Biomedical and Life
Sciences, Singapore Polytechnic, 500 Dover
Road, Singapore 139651
| | - Gang Chen
- Centre for Biomedical and Life
Sciences, Singapore Polytechnic, 500 Dover
Road, Singapore 139651
| | - Xiankun Tong
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555
Zu Chong Zhi Road, Shanghai 201203, China
| | - Wei Tang
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555
Zu Chong Zhi Road, Shanghai 201203, China
| | - Jin Zhu
- Shanghai Key Laboratory of New
Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Mei Long Road, Shanghai
200237, China
| | - Jianping Zuo
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555
Zu Chong Zhi Road, Shanghai 201203, China
| | - Hualiang Jiang
- Shanghai Key Laboratory of New
Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Mei Long Road, Shanghai
200237, China
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555
Zu Chong Zhi Road, Shanghai 201203, China
| | - Cai-Guang Yang
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555
Zu Chong Zhi Road, Shanghai 201203, China
| | - Jian Li
- Shanghai Key Laboratory of New
Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Mei Long Road, Shanghai
200237, China
| | - Weiliang Zhu
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555
Zu Chong Zhi Road, Shanghai 201203, China
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79
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Aravapalli S, Lai H, Teramoto T, Alliston KR, Lushington GH, Ferguson EL, Padmanabhan R, Groutas WC. Inhibitors of Dengue virus and West Nile virus proteases based on the aminobenzamide scaffold. Bioorg Med Chem 2012; 20:4140-8. [PMID: 22632792 PMCID: PMC3563422 DOI: 10.1016/j.bmc.2012.04.055] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Revised: 04/19/2012] [Accepted: 04/27/2012] [Indexed: 10/28/2022]
Abstract
Dengue and West Nile viruses (WNV) are mosquito-borne members of flaviviruses that cause significant morbidity and mortality. There is no approved vaccine or antiviral drugs for human use to date. In this study, a series of functionalized meta and para aminobenzamide derivatives were synthesized and subsequently screened in vitro against Dengue virus and West Nile virus proteases. Four active compounds were identified which showed comparable activity toward the two proteases and shared in common a meta or para(phenoxy)phenyl group. The inhibition constants (K(i)) for the most potent compound 7n against Dengue and West Nile virus proteases were 8.77 and 5.55 μM, respectively. The kinetics data support a competitive mode of inhibition of both proteases by compound 7n. This conclusion is further supported by molecular modeling. This study reveals a new chemical scaffold which is amenable to further optimization to yield potent inhibitors of the viral proteases via the combined utilization of iterative medicinal chemistry/structure-activity relationship studies and in vitro screening.
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Affiliation(s)
- Sridhar Aravapalli
- Department of Chemistry, Wichita State University, Wichita, Kansas 67260, USA
| | - Huiguo Lai
- Department of Microbiology and Immunology, Georgetown University Medical Center, Washington, DC 20057, USA
| | - Tadahisa Teramoto
- Department of Microbiology and Immunology, Georgetown University Medical Center, Washington, DC 20057, USA
| | - Kevin R. Alliston
- Department of Chemistry, Wichita State University, Wichita, Kansas 67260, USA
| | - Gerald H. Lushington
- Molecular Graphics and Modeling Laboratory, The University of Kansas, Lawrence, KS 66045, USA
| | - Eron L. Ferguson
- Department of Chemistry, Wichita State University, Wichita, Kansas 67260, USA
| | - R. Padmanabhan
- Department of Microbiology and Immunology, Georgetown University Medical Center, Washington, DC 20057, USA
| | - William C. Groutas
- Department of Chemistry, Wichita State University, Wichita, Kansas 67260, USA
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80
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Retro peptide-hybrids as selective inhibitors of the Dengue virus NS2B-NS3 protease. Antiviral Res 2012; 94:72-9. [DOI: 10.1016/j.antiviral.2012.02.008] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Revised: 02/14/2012] [Accepted: 02/16/2012] [Indexed: 11/19/2022]
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81
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Access to C-protected β-amino-aldehydes via transacetalization of 6-alcoxy tetrahydrooxazinones and use for pseudo-peptide synthesis. Tetrahedron 2012. [DOI: 10.1016/j.tet.2012.01.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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82
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Tomlinson SM, Watowich SJ. Use of parallel validation high-throughput screens to reduce false positives and identify novel dengue NS2B-NS3 protease inhibitors. Antiviral Res 2012; 93:245-252. [PMID: 22193283 PMCID: PMC3266433 DOI: 10.1016/j.antiviral.2011.12.003] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2011] [Revised: 12/05/2011] [Accepted: 12/06/2011] [Indexed: 01/10/2023]
Abstract
Dengue virus (DENV), a mosquito-borne member of the family Flaviviridae, is a significant global pathogen affecting primarily tropical and subtropical regions of the world and placing tremendous burden on the limited medical infrastructure that exists in many of the developing countries located within these regions. Recent outbreaks in developed countries, including Australia (Hanna et al., 2009), France (La Ruche et al., 2010), Taiwan (Kuan et al., 2010), and the USA (CDC, 2010), lead many researchers to believe that continued emergence into more temperate latitudes is likely. A primary concern is that there are no approved vaccines or antiviral therapies to treat DENV infections. Since the viral NS2B-NS3 protease (DENV NS2B-NS3pro) is required for virus replication, it provides a strategic target for the development of antiviral drugs. In this study, proof-of-concept high-throughput screenings (HTSs) were performed to unambiguously identify dengue 2 virus (DEN2V) NS2B-NS3pro inhibitors from a library of 2000 compounds. Validation screens were performed in parallel to concurrently eliminate insoluble, auto-fluorescing, and/or nonspecific inhibitors. Kinetic analyses of the hits revealed that parallel substrate fluorophore (AMC) interference controls and trypsin inhibition controls were able to reduce false positive rates due to solubility and fluorophore interference while the trypsin inhibition control additionally eliminated non-specific inhibitors. We identified five DEN2V NS2B-NS3pro inhibitors that also inhibited the related West Nile virus (WNV) protease (NS2B-NS3pro), but did not inhibit the trypsin protease. Biochemical analyses revealed various mechanisms of inhibition including competitive and mixed noncompetitive inhibition, with the lowest K(i) values being 12±1.5 μM for DEN2V NS2B-NS3pro and 2±0.2 μM for WNV NS2B-NS3pro.
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Affiliation(s)
- Suzanne M Tomlinson
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, United States
| | - Stanley J Watowich
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, United States.
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83
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Tiew KC, Dou D, Teramoto T, Lai H, Alliston KR, Lushington GH, Padmanabhan R, Groutas WC. Inhibition of Dengue virus and West Nile virus proteases by click chemistry-derived benz[d]isothiazol-3(2H)-one derivatives. Bioorg Med Chem 2012; 20:1213-21. [PMID: 22249124 PMCID: PMC3279297 DOI: 10.1016/j.bmc.2011.12.047] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Revised: 12/14/2011] [Accepted: 12/21/2011] [Indexed: 11/18/2022]
Abstract
Two click chemistry-derived focused libraries based on the benz[d]isothiazol-3(2H)-one scaffold were synthesized and screened against Dengue virus and West Nile virus NS2B-NS3 proteases. Several compounds (4l, 7j-n) displayed noteworthy inhibitory activity toward Dengue virus NS2B-NS3 protease in the absence and presence of added detergent. These compounds could potentially serve as a launching pad for a hit-to-lead optimization campaign.
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Affiliation(s)
- Kok-Chuan Tiew
- Department of Chemistry, Wichita State University, Wichita, Kansas 67260, USA
| | - Dengfeng Dou
- Department of Chemistry, Wichita State University, Wichita, Kansas 67260, USA
| | - Tadahisa Teramoto
- Department of Microbiology and Immunology, Georgetown University Medical Center, Washington, DC 20057, USA
| | - Huiguo Lai
- Department of Microbiology and Immunology, Georgetown University Medical Center, Washington, DC 20057, USA
| | - Kevin R. Alliston
- Department of Chemistry, Wichita State University, Wichita, Kansas 67260, USA
| | - Gerald H. Lushington
- Molecular Graphics and Modeling Laboratory, The University of Kansas, Lawrence, KS 66045, USA
| | - R. Padmanabhan
- Department of Microbiology and Immunology, Georgetown University Medical Center, Washington, DC 20057, USA
| | - William C. Groutas
- Department of Chemistry, Wichita State University, Wichita, Kansas 67260, USA
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84
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de la Cruz L, Nguyen THD, Ozawa K, Shin J, Graham B, Huber T, Otting G. Binding of low molecular weight inhibitors promotes large conformational changes in the dengue virus NS2B-NS3 protease: fold analysis by pseudocontact shifts. J Am Chem Soc 2011; 133:19205-15. [PMID: 22007671 DOI: 10.1021/ja208435s] [Citation(s) in RCA: 108] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The two-component dengue virus NS2B-NS3 protease (DEN NS2B-NS3pro) is an established drug target, but inhibitor design is hampered by the lack of a crystal structure of the protease in its fully active form. In solution and without inhibitors, the functionally important C-terminal segment of the NS2B cofactor is dissociated from DEN NS3pro ("open state"), necessitating a large structural change to produce the "closed state" thought to underpin activity. We analyzed the fold of DEN NS2B-NS3pro in solution with and without bound inhibitor by nuclear magnetic resonance (NMR) spectroscopy. Multiple paramagnetic lanthanide tags were attached to different sites to generate pseudocontact shifts (PCS). In the face of severe spectral overlap and broadening of many signals by conformational exchange, methods for assignment of (15)N-HSQC cross-peaks included selective mutation, combinatorial isotope labeling, and comparison of experimental PCSs and PCSs back-calculated for a structural model of the closed conformation built by using the structure of the related West Nile virus (WNV) protease as a template. The PCSs show that, in the presence of a positively charged low-molecular weight inhibitor, the enzyme assumes a closed state that is very similar to the closed state previously observed for the WNV protease. Therefore, a model of the protease built on the closed conformation of the WNV protease is a better template for rational drug design than available crystal structures, at least for positively charged inhibitors. To assess the open state, we created a binding site for a Gd(3+) complex and measured paramagnetic relaxation enhancements. The results show that the specific open conformation displayed in the crystal of DEN NS2B-NS3pro is barely populated in solution. The techniques used open an avenue to the fold analysis of proteins that yield poor NMR spectra, as PCSs from multiple sites in combination with model building generate powerful information even from incompletely assigned (15)N-HSQC spectra.
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Affiliation(s)
- Laura de la Cruz
- Research School of Chemistry, Australian National University, Canberra, ACT 0200, Australia
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85
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Abstract
Dengue is a mosquito-borne viral hemorrhagic disease that is a major threat to human health in tropical and subtropical regions. Here we report crystal structures of a peptide covalently bound to dengue virus serotype 3 (DENV-3) protease as well as the serine-protease inhibitor aprotinin bound to the same enzyme. These structures reveal, for the first time, a catalytically active, closed conformation of the DENV protease. In the presence of the peptide, the DENV-3 protease forms the closed conformation in which the hydrophilic β-hairpin region of NS2B wraps around the NS3 protease core, in a manner analogous to the structure of West Nile virus (WNV) protease. Our results confirm that flavivirus proteases form the closed conformation during proteolysis, as previously proposed for WNV. The current DENV-3 protease structures reveal the detailed interactions at the P4' to P3 sites of the substrate. The new structural information explains the sequence preference, particularly for long basic residues in the nonprime side, as well as the difference in substrate specificity between the WNV and DENV proteases at the prime side. Structural analysis of the DENV-3 protease-peptide complex revealed a pocket that is formed by residues from NS2B and NS3; this pocket also exists in the WNV NS2B/NS3 protease structure and could be targeted for potential antivirus development. The structural information presented in the current study is invaluable for the design of specific inhibitors of DENV protease.
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86
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Schüller A, Yin Z, Brian Chia C, Doan DN, Kim HK, Shang L, Loh TP, Hill J, Vasudevan SG. Tripeptide inhibitors of dengue and West Nile virus NS2B–NS3 protease. Antiviral Res 2011; 92:96-101. [DOI: 10.1016/j.antiviral.2011.07.002] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2011] [Revised: 06/27/2011] [Accepted: 07/04/2011] [Indexed: 11/16/2022]
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Abstract
We report a novel inhibitor that selectively suppresses dengue virus (DENV) by targeting viral NS4B protein. The inhibitor was identified by screening a 1.8-million-compound library using a luciferase replicon of DENV serotype 2 (DENV-2). The compound specifically inhibits all four serotypes of DENV (50% effective concentration [EC(50)], 1 to 4 μM; and 50% cytotoxic concentration [CC(50)], >40 μM), but it does not inhibit closely related flaviviruses (West Nile virus and yellow fever virus) or nonflaviviruses (Western equine encephalomyelitis virus, Chikungunya virus, and vesicular stomatitis virus). A mode-of-action study suggested that the compound inhibits viral RNA synthesis. Replicons resistant to the inhibitor were selected in cell culture. Sequencing of the resistant replicons revealed two mutations (P104L and A119T) in the viral NS4B protein. Genetic analysis, using DENV-2 replicon and recombinant viruses, demonstrated that each of the two NS4B mutations alone confers partial resistance and double mutations confer additive resistance to the inhibitor in mammalian cells. In addition, we found that a replication defect caused by a lethal NS4B mutation could be partially rescued through trans complementation. The ability to complement NS4B in trans affected drug sensitivity when a single cell was coinfected with drug-sensitive and drug-resistant viruses. Mechanistically, NS4B was previously shown to interact with the viral NS3 helicase domain; one of the two NS4B mutations recovered in our resistance analysis-P104L-abolished the NS3-NS4B interaction (I. Umareddy, A. Chao, A. Sampath, F. Gu, and S. G. Vasudevan, J. Gen. Virol. 87:2605-2614, 2006). Collectively, the results suggest that the identified inhibitor targets the DENV NS4B protein, leading to a defect in viral RNA synthesis.
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88
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Synthesis and biological evaluation of α-ketoamides as inhibitors of the Dengue virus protease with antiviral activity in cell-culture. Bioorg Med Chem 2011; 19:4067-74. [PMID: 21641807 DOI: 10.1016/j.bmc.2011.05.015] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2011] [Revised: 05/10/2011] [Accepted: 05/10/2011] [Indexed: 11/21/2022]
Abstract
The development of small molecule inhibitors of the viral protease is of considerable interest for the treatment of emergent flaviviral diseases such as Dengue or West Nile fever. Until today little progress has been made in finding drug-like compounds that inhibit the protease and provide a starting point for lead optimization. We describe here the initial steps of a drug discovery effort that focused on the styryl pharmacophore, combined with a ketoamide function to serve as electrophilic trap for the catalytic serine. This resulted in a fragment-like lead compound with reasonable target affinity and good ligand efficiency, which was extensively modified to explore structure-activity relationships. Selected compounds were cross-tested against the West Nile virus protease and thrombin, indicating that selectivity for one or more flaviviral proteases can be achieved. Finally, the antiviral activity of several protease inhibitors was confirmed in a cell-culture model of Dengue virus replication. The SAR presented here may serve as starting point for further drug discovery efforts with the aim of targeting flaviviral proteases.
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89
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Knehans T, Schüller A, Doan DN, Nacro K, Hill J, Güntert P, Madhusudhan MS, Weil T, Vasudevan SG. Structure-guided fragment-based in silico drug design of dengue protease inhibitors. J Comput Aided Mol Des 2011; 25:263-74. [DOI: 10.1007/s10822-011-9418-0] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2010] [Accepted: 02/07/2011] [Indexed: 11/24/2022]
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90
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91
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Tomlinson SM, Watowich SJ. Anthracene-based inhibitors of dengue virus NS2B-NS3 protease. Antiviral Res 2010; 89:127-35. [PMID: 21185332 DOI: 10.1016/j.antiviral.2010.12.006] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Revised: 12/14/2010] [Accepted: 12/15/2010] [Indexed: 11/18/2022]
Abstract
Dengue virus (DENV) is a mosquito-borne flavivirus that has strained global healthcare systems throughout tropical and subtropical regions of the world. In addition to plaguing developing nations, it has re-emerged in several developed countries with recent outbreaks in the USA (CDC, 2010), Australia (Hanna et al., 2009), Taiwan (Kuan et al., 2010) and France (La Ruche et al., 2010). DENV infection can cause significant disease, including dengue fever, dengue hemorrhagic fever, dengue shock syndrome, and death. There are no approved vaccines or antiviral therapies to prevent or treat dengue-related illnesses. However, the viral NS2B-NS3 protease complex provides a strategic target for antiviral drug development since NS3 protease activity is required for virus replication. Recently, we reported two compounds with inhibitory activity against the DENV protease in vitro and antiviral activity against dengue 2 (DEN2V) in cell culture (Tomlinson et al., 2009a). Analogs of one of the lead compounds were purchased, tested in protease inhibition assays, and the data evaluated with detailed kinetic analyses. A structure activity relationship (SAR) identified key atomic determinants (i.e. functional groups) important for inhibitory activity. Four "second series" analogs were selected and tested to validate our SAR and structural models. Here, we report improvements to inhibitory activity ranging between ∼2- and 60-fold, resulting in selective low micromolar dengue protease inhibitors.
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Affiliation(s)
- Suzanne M Tomlinson
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, United States
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92
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Tambunan USF, Alamudi S. Designing cyclic peptide inhibitor of dengue virus NS3-NS2B protease by using molecular docking approach. Bioinformation 2010; 5:250-4. [PMID: 21364826 PMCID: PMC3055701 DOI: 10.6026/97320630005250] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Accepted: 11/09/2010] [Indexed: 11/23/2022] Open
Abstract
Peptides are preferred for designing inhibitors because of their high activity and specificity. Seven cyclopentapeptide inhibitors were designed in this
study against dengue virus type 2 (DEN-2) NS3-NS2B protease: CKRRC, CGRRC, CRGRC, CRTRC, CTRRC, CKRKC and CRRKC. Docking
analysis was performed to study the enzyme-inhibitor binding interactions. The free energy binding and estimated Ki values for all the inhibitors were
found to be small (within micromolar range), indicating that the inhibitors bind considerably well to the binding site. The results showed that the
cyclopentapeptide CKRKC was the best peptide inhibitor candidate with estimated free binding energy of -8.39 kcal/mol and Ki of 0.707 µM when
compared to the standard inhibitor Bz-Nle-Lys-Arg-Arg-H that has been experimentally tested and shown to exhibit Ki value of 5.8 µM. Several modes
of weak interactions were observed between the cyclopentapeptide CKRKC and the active site of DEN-2 NS3-NS2B protease. Thus, the
cyclopentapeptide is proposed as a potential inhibitor to the NS3-NS2B protease activities of DEN-2. While these preliminary results are promising,
further experimental investigation is necessary to validate the results.
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Affiliation(s)
- Usman Sumo Friend Tambunan
- Department of Chemistry, Faculty of Mathematics and Natural Science, University of Indonesia, Depok Campus, Depok 16424, Indonesia
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93
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Shiryaev SA, Cheltsov AV, Gawlik K, Ratnikov BI, Strongin AY. Virtual ligand screening of the National Cancer Institute (NCI) compound library leads to the allosteric inhibitory scaffolds of the West Nile Virus NS3 proteinase. Assay Drug Dev Technol 2010; 9:69-78. [PMID: 21050032 DOI: 10.1089/adt.2010.0309] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Viruses of the genus Flavivirus are responsible for significant human disease and mortality. The N-terminal domain of the flaviviral nonstructural (NS)3 protein codes for the serine, chymotrypsin-fold proteinase (NS3pro). The presence of the nonstructural (NS)2B cofactor, which is encoded by the upstream gene in the flaviviral genome, is necessary for NS3pro to exhibit its proteolytic activity. The two-component NS2B-NS3pro functional activity is essential for the viral polyprotein processing and replication. Both the structure and the function of NS2B-NS3pro are conserved in the Flavivirus family. Because of its essential function in the posttranslational processing of the viral polyprotein precursor, NS2B-NS3pro is a promising target for anti-flavivirus drugs. To identify selective inhibitors with the reduced cross-reactivity and off-target effects, we focused our strategy on the allosteric inhibitors capable of targeting the NS2B-NS3pro interface rather than the NS3pro active site. Using virtual ligand screening of the diverse, ∼275,000-compound library and the catalytic domain of the two-component West Nile virus (WNV) NS2B-NS3pro as a receptor, we identified a limited subset of the novel inhibitory scaffolds. Several of the discovered compounds performed as allosteric inhibitors and exhibited a nanomolar range potency in the in vitro cleavage assays. The inhibitors were also potent in cell-based assays employing the sub-genomic, luciferase-tagged WNV and Dengue viral replicons. The selectivity of the inhibitors was confirmed using the in vitro cleavage assays with furin, a human serine proteinase, the substrate preferences of which are similar to those of WNV NS2B-NS3pro. Conceptually, the similar in silico drug discovery strategy may be readily employed for the identification of inhibitors of other flaviviruses.
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Affiliation(s)
- Sergey A Shiryaev
- Inflammatory and Infectious Disease Center, Sanford-Burnham Medical Research Institute, 10901 N. Torrey Pines Road, La Jolla, CA 92037, USA
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94
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Novel dengue virus-specific NS2B/NS3 protease inhibitor, BP2109, discovered by a high-throughput screening assay. Antimicrob Agents Chemother 2010; 55:229-38. [PMID: 20937790 DOI: 10.1128/aac.00855-10] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Dengue virus (DENV) causes disease globally, with an estimated 25 to 100 million new infections per year. At present, no effective vaccine is available, and treatment is supportive. In this study, we identified BP2109, a potent and selective small-molecule inhibitor of the DENV NS2B/NS3 protease, by a high-throughput screening assay using a recombinant protease complex consisting of the central hydrophilic portion of NS2B and the N terminus of the protease domain. BP2109 inhibited DENV (serotypes 1 to 4), but not Japanese encephalitis virus (JEV), replication and viral RNA synthesis without detectable cytotoxicity. The compound inhibited recombinant DENV-2 NS2B/NS3 protease with a 50% inhibitory concentration (IC(50)) of 15.43 ± 2.12 μM and reduced the reporter expression of the DENV-2 replicon with a 50% effective concentration (EC(50)) of 0.17 ± 0.01 μM. Sequencing analyses of several individual clones derived from BP2109-resistant DENV-2 RNAs revealed that two amino acid substitutions (R55K and E80K) are found in the region of NS2B, a cofactor of the NS2B/NS3 protease complex. The introduction of R55K and E80K double mutations into the dengue virus NS2B/NS3 protease and a dengue virus replicon construct conferred 10.3- and 73.8-fold resistance to BP2109, respectively. The E80K mutation was further determined to be the key mutation conferring dengue virus replicon resistance (61.3-fold) to BP2109, whereas the R55K mutation alone did not affect resistance to BP2109. Both the R55K and E80K mutations are located in the central hydrophilic portion of the NS2B cofactor, where extensive interactions with the NS3pro domain exist. Thus, our data provide evidence that BP2109 likely inhibits DENV by a novel mechanism.
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95
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Shiryaev SA, Strongin AY. Structural and functional parameters of the flaviviral protease: a promising antiviral drug target. Future Virol 2010; 5:593-606. [PMID: 21076642 DOI: 10.2217/fvl.10.39] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Flaviviruses have a single-strand, positive-polarity RNA genome that encodes a single polyprotein. The polyprotein is comprised of seven nonstructural (NS) and three structural proteins. The N- and C-terminal parts of NS3 represent the serine protease and the RNA helicase, respectively. The cleavage of the polyprotein by the protease is required to produce the individual viral proteins, which assemble a new viral progeny. Conversely, inactivation of the protease blocks viral infection. Both the protease and the helicase are conserved among flaviviruses. As a result, NS3 is a promising drug target in flaviviral infections. This article examines the West Nile virus NS3 with an emphasis on the structural and functional parameters of the protease, the helicase and their cofactors.
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Affiliation(s)
- Sergey A Shiryaev
- Inflammatory & Infectious Disease Center, Sanford-Burnham Medical Research Institute, La Jolla, CA 92037, USA
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96
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Small molecule drug discovery for Dengue and West Nile viruses: applying experience from hepatitis C virus. Future Med Chem 2010; 2:1181-203. [DOI: 10.4155/fmc.10.195] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
There are currently no specific treatments for infection with Dengue virus (DENV) and West Nile Virus (WNV). Drug-discovery programs are underway for both viruses, but as yet no small molecules have advanced to clinical trials. Hepatitis C virus (HCV) is a related flavivirus that has been the focus of intense drug discovery efforts for the last two decades. Many approaches currently being pursued for DENV and WNV have been previously attempted for HCV with varying degrees of success. The experience with HCV may direct DENV and WNV efforts towards approaches with the best chance of success. Based on experience with HCV, the viral polymerase and protease are attractive targets to focus on since these have been most successful to date. Cell-based phenotypic screening may also yield attractive inhibitors. The helicase and methyltransferase enzymes are likely to prove difficult targets and host target approaches are fraught with safety concerns.
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97
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Wichapong K, Pianwanit S, Sippl W, Kokpol S. Homology modeling and molecular dynamics simulations of Dengue virus NS2B/NS3 protease: insight into molecular interaction. J Mol Recognit 2010; 23:283-300. [PMID: 19693793 DOI: 10.1002/jmr.977] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The pathogenic West Nile virus (WNV) and Dengue virus (DV) are growing global threats for which there are no specific treatments. Both viruses possess a two component NS2B/NS3 protease which cleaves viral precursor proteins. Whereas for the WNV protease two crystal structures in complex with an inhibitor have been solved recently, no such information is available for the DV protease. Here, we report the generation of a homology model of DV NS2B/NS3 protease. Since it is known from the related WNV protease that it adopts a distinct conformation in free and in inhibitor-complexed form, a special emphasis was given to the analysis of the protease flexibility. Therefore, several models of DV NS2B/NS3 protease complexed with the peptidic inhibitor (Bz-Nle(P4)-Lys(P3)-Arg(P2)-Arg(P1)-H) were generated. The first DV protease model (DV-1) was constructed using the available crystal structure of the apo DV NS2B/NS3 protease. The second model (DV-2) was built taking the WNV NS3/NS2B protease in the inhibitor-complexed form as the template structure. Molecular dynamics simulations which were carried out for the WNV crystal structures as well as for the DV models provided an understanding of the role of NS2B for maintaining the protease in the active conformation. It was also demonstrated that NS2B is not only important for maintaining NS3 in the active form, but is also essential for establishing the interaction between residues from the S2 pocket and the peptidic inhibitor. The DV NS2B/NS3 model in the productive conformation can now be used for structure-based design purposes.
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Affiliation(s)
- Kanin Wichapong
- Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
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98
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Design, structure-based focusing and in silico screening of combinatorial library of peptidomimetic inhibitors of Dengue virus NS2B-NS3 protease. J Comput Aided Mol Des 2010; 24:195-212. [DOI: 10.1007/s10822-010-9326-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2009] [Accepted: 03/08/2010] [Indexed: 10/19/2022]
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99
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Abstract
BACKGROUND The guanidine group defines chemical and physicochemical properties of many compounds of medical interest and guanidine-containing derivatives constitute a very important class of therapeutic agents suitable for the treatment of a wide spectrum of diseases. OBJECTIVE To review the most important pharmacological properties, mechanisms of action and therapeutic uses of simple guanidine derivatives, cyclic analogues of guanidines as well as peptides, peptidomimetics and peptoids incorporating arginine. METHODS The review presents both the recent patent literature and original papers dealing with guanidine derivatives that show interesting biological activity and emphasizes the newest developing drugs. CONCLUSION Recent achievements in the synthesis of guanidine-containing molecules with diverse chemical, biochemical and pharmacological properties make them of great importance to the design and development of novel drugs acting at CNS, anti-inflammatory agents, inhibitors of Na(+)/H(+) exchanger, inhibitors of NO synthase, antithrombotic, antidiabetic and chemotherapeutic agents as well as guanidinium-based transporters and vectors.
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Affiliation(s)
- Franciszek Saczewski
- Department of Chemical Technology of Drugs, Medical University of Gdansk, Al. Gen. Hallera 107, Gdansk, Poland.
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100
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Stevens AJ, Gahan ME, Mahalingam S, Keller PA. The medicinal chemistry of dengue fever. J Med Chem 2010; 52:7911-26. [PMID: 19739651 DOI: 10.1021/jm900652e] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Andrew J Stevens
- Department of Chemistry, University of Wollongong, Wollongong 2522, Australia
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