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Goel P, Parvez S, Sharma A. Genomic analyses of aminoacyl tRNA synthetases from human-infecting helminths. BMC Genomics 2019; 20:333. [PMID: 31046663 PMCID: PMC6498573 DOI: 10.1186/s12864-019-5679-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 04/09/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Helminth infections affect ~ 60% of the human population that lives in tropical and subtropical regions worldwide. These infections result in diseases like schistosomiasis, lymphatic filariasis, river blindness and echinococcosis. Here we provide a comprehensive computational analysis of the aminoacyl tRNA synthetase (aaRS) enzyme family from 27 human-infecting helminths. Our analyses support the idea that several helminth aaRSs can be targeted for drug repurposing or for development of new drugs. For experimental validation, we focused on Onchocerciasis (also known as "river blindness"), a filarial vector-borne disease that is prevalent in Africa and Latin America. We show that halofuginone (HF) can act as a potent inhibitor of Onchocerca volvulus prolyl tRNA synthetase (OvPRS). RESULTS The conserved enzyme family of aaRSs has been validated as druggable targets in numerous eukaryotic parasites. We thus embarked on assessing aaRSs from the genomes of 27 helminths that cause infections in humans. In order to delineate the distribution of aaRSs per genome we utilized Hidden Markov Models of aaRS catalytic domains to identify all orthologues. We note that Fasciola hepatica genome encodes the highest number of aaRS-like proteins (69) whereas Taenia asiatica has the lowest count (32). The number of genes for any particular aaRS-like protein varies from 1 to 8 in these 27 studied helminths. Sequence alignments of helminth-encoded lysyl, prolyl, leucyl and threonyl tRNA synthetases suggest that various known aaRS inhibitors like Cladosporin, Halofuginone, Benzoborale and Borrelidin may be of utility against helminths. The recombinantly expressed Onchocerca volvulus PRS was used as proof of concept for targeting aaRS with drug-like molecules like HF. CONCLUSIONS Systematic analysis of unique subdomains within helminth aaRSs reveals the presence of a number of non-canonical domains like PAC3, Utp-14, Pex2_Pex12 fused to catalytic domains in the predicted helminth aaRSs. We have established a platform for biochemical validation of a large number of helminth aaRSs that can be targeted using available inhibitors to jump-start drug repurposing against human helminths.
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Affiliation(s)
- Preeti Goel
- 0000 0004 0498 7682grid.425195.eStructural Parasitology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, 110067 India ,0000 0004 0498 8167grid.411816.bDepartment of Toxicology, School of Chemical and Life Sciences, Jamia Hamdard, New Delhi, 110063 India
| | - Suhel Parvez
- 0000 0004 0498 8167grid.411816.bDepartment of Toxicology, School of Chemical and Life Sciences, Jamia Hamdard, New Delhi, 110063 India
| | - Amit Sharma
- 0000 0004 0498 7682grid.425195.eStructural Parasitology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, 110067 India
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Nyamai DW, Tastan Bishop Ö. Aminoacyl tRNA synthetases as malarial drug targets: a comparative bioinformatics study. Malar J 2019; 18:34. [PMID: 30728021 PMCID: PMC6366043 DOI: 10.1186/s12936-019-2665-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 01/27/2019] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Treatment of parasitic diseases has been challenging due to evolution of drug resistant parasites, and thus there is need to identify new class of drugs and drug targets. Protein translation is important for survival of malarial parasite, Plasmodium, and the pathway is present in all of its life cycle stages. Aminoacyl tRNA synthetases are primary enzymes in protein translation as they catalyse amino acid addition to the cognate tRNA. This study sought to understand differences between Plasmodium and human aminoacyl tRNA synthetases through bioinformatics analysis. METHODS Plasmodium berghei, Plasmodium falciparum, Plasmodium fragile, Plasmodium knowlesi, Plasmodium malariae, Plasmodium ovale, Plasmodium vivax, Plasmodium yoelii and human aminoacyl tRNA synthetase sequences were retrieved from UniProt database and grouped into 20 families based on amino acid specificity. These families were further divided into two classes. Both families and classes were analysed. Motif discovery was carried out using the MEME software, sequence identity calculation was done using an in-house Python script, multiple sequence alignments were performed using PROMALS3D and TCOFFEE tools, and phylogenetic tree calculations were performed using MEGA vs 7.0 tool. Possible alternative binding sites were predicted using FTMap webserver and SiteMap tool. RESULTS Motif discovery revealed Plasmodium-specific motifs while phylogenetic tree calculations showed that Plasmodium proteins have different evolutionary history to the human homologues. Human aaRSs sequences showed low sequence identity (below 40%) compared to Plasmodium sequences. Prediction of alternative binding sites revealed potential druggable sites in PfArgRS, PfMetRS and PfProRS at regions that are weakly conserved when compared to the human homologues. Multiple sequence analysis, motif discovery, pairwise sequence identity calculations and phylogenetic tree analysis showed significant differences between parasite and human aaRSs proteins despite functional and structural conservation. These differences may provide a basis for further exploration of Plasmodium aminoacyl tRNA synthetases as potential drug targets. CONCLUSION This study showed that, despite, functional and structural conservation, Plasmodium aaRSs have key differences from the human homologues. These differences in Plasmodium aaRSs can be targeted to develop anti-malarial drugs with less toxicity to the host.
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Affiliation(s)
- Dorothy Wavinya Nyamai
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, 6140, South Africa
| | - Özlem Tastan Bishop
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, 6140, South Africa.
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New leads for drug repurposing against malaria. Drug Discov Today 2019; 24:263-271. [DOI: 10.1016/j.drudis.2018.08.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 07/31/2018] [Accepted: 08/06/2018] [Indexed: 02/03/2023]
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Nachiappan M, Jain V, Sharma A, Yogavel M, Jeyakanthan J. Structural and functional analysis of Glutaminyl-tRNA synthetase (TtGlnRS) from Thermus thermophilus HB8 and its complexes. Int J Biol Macromol 2018; 120:1379-1386. [DOI: 10.1016/j.ijbiomac.2018.09.115] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 09/19/2018] [Accepted: 09/19/2018] [Indexed: 10/28/2022]
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Lee EY, Kim S, Kim MH. Aminoacyl-tRNA synthetases, therapeutic targets for infectious diseases. Biochem Pharmacol 2018; 154:424-434. [PMID: 29890143 PMCID: PMC7092877 DOI: 10.1016/j.bcp.2018.06.009] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 06/07/2018] [Indexed: 12/17/2022]
Abstract
Despite remarkable advances in medical science, infection-associated diseases remain among the leading causes of death worldwide. There is a great deal of interest and concern at the rate at which new pathogens are emerging and causing significant human health problems. Expanding our understanding of how cells regulate signaling networks to defend against invaders and retain cell homeostasis will reveal promising strategies against infection. It has taken scientists decades to appreciate that eukaryotic aminoacyl-tRNA synthetases (ARSs) play a role as global cell signaling mediators to regulate cell homeostasis, beyond their intrinsic function as protein synthesis enzymes. Recent discoveries revealed that ubiquitously expressed standby cytoplasmic ARSs sense and respond to danger signals and regulate immunity against infections, indicating their potential as therapeutic targets for infectious diseases. In this review, we discuss ARS-mediated anti-infectious signaling and the emerging role of ARSs in antimicrobial immunity. In contrast to their ability to defend against infection, host ARSs are inevitably co-opted by viruses for survival and propagation. We therefore provide a brief overview of the communication between viruses and the ARS system. Finally, we discuss encouraging new approaches to develop ARSs as therapeutics for infectious diseases.
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Affiliation(s)
- Eun-Young Lee
- Infection and Immunity Research Laboratory, Metabolic Regulation Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea
| | - Sunghoon Kim
- Medicinal Bioconvergence Research Center, Seoul National University, Suwon 16229, Republic of Korea; College of Pharmacy, Seoul National University, Seoul 08826, Republic of Korea
| | - Myung Hee Kim
- Infection and Immunity Research Laboratory, Metabolic Regulation Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea; KRIBB School of Bioscience, Korea University of Science and Technology, Daejeon 34141, Republic of Korea.
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Abstract
It is commonly thought that each globular protein has a single 3D structure, or fold, that fosters its function. In contrast, recent studies have identified several fold-switching proteins whose secondary structures can be remodeled in response to cellular stimuli. Although thought to be rare, we found 96 literature-validated fold-switching proteins by exhaustively searching the database of protein structures [Protein Data Bank (PDB)]. Characterizing these proteins led us to hypothesize that their abundance may be underrepresented in the PDB. Thus, we developed a computational method that identifies fold-switching proteins and used it to estimate that 0.5–4% of PDB proteins switch folds. These results suggest that proteins switch folds with significant frequency, which has implications for cell biology, genomics, and human health. A central tenet of biology is that globular proteins have a unique 3D structure under physiological conditions. Recent work has challenged this notion by demonstrating that some proteins switch folds, a process that involves remodeling of secondary structure in response to a few mutations (evolved fold switchers) or cellular stimuli (extant fold switchers). To date, extant fold switchers have been viewed as rare byproducts of evolution, but their frequency has been neither quantified nor estimated. By systematically and exhaustively searching the Protein Data Bank (PDB), we found ∼100 extant fold-switching proteins. Furthermore, we gathered multiple lines of evidence suggesting that these proteins are widespread in nature. Based on these lines of evidence, we hypothesized that the frequency of extant fold-switching proteins may be underrepresented by the structures in the PDB. Thus, we sought to identify other putative extant fold switchers with only one solved conformation. To do this, we identified two characteristic features of our ∼100 extant fold-switching proteins, incorrect secondary structure predictions and likely independent folding cooperativity, and searched the PDB for other proteins with similar features. Reassuringly, this method identified dozens of other proteins in the literature with indication of a structural change but only one solved conformation in the PDB. Thus, we used it to estimate that 0.5–4% of PDB proteins switch folds. These results demonstrate that extant fold-switching proteins are likely more common than the PDB reflects, which has implications for cell biology, genomics, and human health.
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Das P, Babbar P, Malhotra N, Sharma M, Jachak GR, Gonnade RG, Shanmugam D, Harlos K, Yogavel M, Sharma A, Reddy DS. Specific Stereoisomeric Conformations Determine the Drug Potency of Cladosporin Scaffold against Malarial Parasite. J Med Chem 2018; 61:5664-5678. [DOI: 10.1021/acs.jmedchem.8b00565] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Pronay Das
- Organic Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India
- Academy of Scientific and Innovative Research (AcSIR), New Delhi 110025, India
| | - Palak Babbar
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi 110067, India
| | - Nipun Malhotra
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi 110067, India
| | - Manmohan Sharma
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi 110067, India
| | - Goraknath R. Jachak
- Organic Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India
- Academy of Scientific and Innovative Research (AcSIR), New Delhi 110025, India
| | - Rajesh G. Gonnade
- Academy of Scientific and Innovative Research (AcSIR), New Delhi 110025, India
- Center for Material Characterization, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India
| | - Dhanasekaran Shanmugam
- Academy of Scientific and Innovative Research (AcSIR), New Delhi 110025, India
- Biochemical Sciences Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India
| | - Karl Harlos
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, The Nuffield Department of Medicine, University of Oxford, Oxford OX3 7BN, U.K
| | - Manickam Yogavel
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi 110067, India
| | - Amit Sharma
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi 110067, India
| | - D. Srinivasa Reddy
- Organic Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India
- Academy of Scientific and Innovative Research (AcSIR), New Delhi 110025, India
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Smullen S, McLaughlin NP, Evans P. Chemical synthesis of febrifugine and analogues. Bioorg Med Chem 2018; 26:2199-2220. [PMID: 29681487 DOI: 10.1016/j.bmc.2018.04.027] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 04/10/2018] [Accepted: 04/11/2018] [Indexed: 11/30/2022]
Abstract
The quinazolinone-containing 2,3-disubstituted piperidines febrifugine and isofebrifugine have been the subject of significant research efforts since their occurrence in Dichroa febrifuga and their anti-malarial actions were first described in the late 1940s. Subsequently they have also been shown to be present in other plants belonging to the hydrangea family and various analogues of febrifugine have been prepared in attempts to tune biological properties. The most notable analogue is termed halofuginone and a substantial body of work now demonstrates that this compound possesses potent human disease relevant activities. This review focuses on the literature associated with efforts dedicated towards uncovering the structures of febrifugine and isofebrifugine, the development of practical methods for their synthesis and the syntheses of structural analogues.
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Affiliation(s)
- Shaun Smullen
- Centre for Synthesis and Chemical Biology, School of Chemistry, University College Dublin, Dublin 4, Ireland
| | - Noel P McLaughlin
- Centre for Synthesis and Chemical Biology, School of Chemistry, University College Dublin, Dublin 4, Ireland
| | - Paul Evans
- Centre for Synthesis and Chemical Biology, School of Chemistry, University College Dublin, Dublin 4, Ireland.
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Manickam Y, Chaturvedi R, Babbar P, Malhotra N, Jain V, Sharma A. Drug targeting of one or more aminoacyl-tRNA synthetase in the malaria parasite Plasmodium falciparum. Drug Discov Today 2018; 23:1233-1240. [PMID: 29408369 DOI: 10.1016/j.drudis.2018.01.050] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 01/02/2018] [Accepted: 01/29/2018] [Indexed: 11/28/2022]
Abstract
Malaria remains a major infectious disease and, despite incidence reduction, it threatens resurgence in drug-resistant forms. Antimalarial drugs remain the mainstay of therapeutic options and hence there is a constant need to identify and validate new druggable targets. Plasmodium falciparum aminoacyl-tRNA synthetases (Pf-aaRSs) drive protein translation and are potent targets for development of next-generation antimalarials. Here, we detail advances made in structural-biology-based investigations in Pf-aaRSs and discuss their distribution of druggable pockets. This review establishes a platform for systematic experimental dissection of malarial parasite aaRSs as a new focus for sustained drug development efforts against malaria.
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Affiliation(s)
- Yogavel Manickam
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi 110067, India
| | - Rini Chaturvedi
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi 110067, India
| | - Palak Babbar
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi 110067, India
| | - Nipun Malhotra
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi 110067, India
| | - Vitul Jain
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi 110067, India; Present address: Division of Structural Biology, Wellcome Trust Centre for Human Genetics, The Nuffield Department of Medicine, University of Oxford, Oxford OX3 7BN, UK
| | - Amit Sharma
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi 110067, India.
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Sindikubwabo F, Ding S, Hussain T, Ortet P, Barakat M, Baumgarten S, Cannella D, Palencia A, Bougdour A, Belmudes L, Couté Y, Tardieux I, Botté CY, Scherf A, Hakimi MA. Modifications at K31 on the lateral surface of histone H4 contribute to genome structure and expression in apicomplexan parasites. eLife 2017; 6:29391. [PMID: 29101771 PMCID: PMC5685513 DOI: 10.7554/elife.29391] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 11/02/2017] [Indexed: 12/22/2022] Open
Abstract
An unusual genome architecture characterizes the two related human parasitic pathogens Plasmodium falciparum and Toxoplasma gondii. A major fraction of the bulk parasite genome is packaged as transcriptionally permissive euchromatin with few loci embedded in silenced heterochromatin. Primary chromatin shapers include histone modifications at the nucleosome lateral surface close to the DNA but their mode of action remains unclear. We now identify versatile modifications at Lys31 within the globular domain of histone H4 that crucially determine genome organization and expression in Apicomplexa parasites. H4K31 acetylation at the promoter correlates with, and perhaps directly regulates, gene expression in both parasites. By contrast, monomethylated H4K31 is enriched in the core body of T. gondii active genes but inversely correlates with transcription, whereas it is unexpectedly enriched at transcriptionally inactive pericentromeric heterochromatin in P. falciparum, a region devoid of the characteristic H3K9me3 histone mark and its downstream effector HP1.
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Affiliation(s)
- Fabien Sindikubwabo
- Institute for Advanced Biosciences (IAB), Team Host-pathogen interactions and immunity to infection, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
| | - Shuai Ding
- Unité de Biologie des Interactions Hôte-Parasite, Institut Pasteur, CNRS, ERL 9195, INSERM, Unit U1201, Paris, France
| | - Tahir Hussain
- Institute for Advanced Biosciences (IAB), Team Host-pathogen interactions and immunity to infection, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
| | - Philippe Ortet
- Aix-Marseille Univ, CEA, CNRS, UMR 7265, BIAM-LEMIRE, St-Paul-lez-Durance, France
| | - Mohamed Barakat
- Aix-Marseille Univ, CEA, CNRS, UMR 7265, BIAM-LEMIRE, St-Paul-lez-Durance, France
| | - Sebastian Baumgarten
- Unité de Biologie des Interactions Hôte-Parasite, Institut Pasteur, CNRS, ERL 9195, INSERM, Unit U1201, Paris, France
| | - Dominique Cannella
- Institute for Advanced Biosciences (IAB), Team Host-pathogen interactions and immunity to infection, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
| | - Andrés Palencia
- Institute for Advanced Biosciences (IAB), Team Host-pathogen interactions and immunity to infection, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
| | - Alexandre Bougdour
- Institute for Advanced Biosciences (IAB), Team Host-pathogen interactions and immunity to infection, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
| | - Lucid Belmudes
- Université Grenoble Alpes, CEA, INSERM, Grenoble, France
| | - Yohann Couté
- Université Grenoble Alpes, CEA, INSERM, Grenoble, France
| | - Isabelle Tardieux
- Institute for Advanced Biosciences (IAB), Team Membrane and Cell Dynamics of Host Parasite Interactions, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
| | - Cyrille Y Botté
- Institute for Advanced Biosciences (IAB), Team ApicoLipid, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
| | - Artur Scherf
- Unité de Biologie des Interactions Hôte-Parasite, Institut Pasteur, CNRS, ERL 9195, INSERM, Unit U1201, Paris, France
| | - Mohamed-Ali Hakimi
- Institute for Advanced Biosciences (IAB), Team Host-pathogen interactions and immunity to infection, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
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Bule MH, Ahmed I, Maqbool F, Zia MA. Quinazolinone Derivatives as a Potential Class of Compounds in Malaria Drug Discovery. INT J PHARMACOL 2017. [DOI: 10.3923/ijp.2017.818.831] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Targeting Prolyl-tRNA Synthetase to Accelerate Drug Discovery against Malaria, Leishmaniasis, Toxoplasmosis, Cryptosporidiosis, and Coccidiosis. Structure 2017; 25:1495-1505.e6. [PMID: 28867614 DOI: 10.1016/j.str.2017.07.015] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2017] [Revised: 06/02/2017] [Accepted: 07/26/2017] [Indexed: 11/24/2022]
Abstract
Developing anti-parasitic lead compounds that act on key vulnerabilities are necessary for new anti-infectives. Malaria, leishmaniasis, toxoplasmosis, cryptosporidiosis and coccidiosis together kill >500,000 humans annually. Their causative parasites Plasmodium, Leishmania, Toxoplasma, Cryptosporidium and Eimeria display high conservation in many housekeeping genes, suggesting that these parasites can be attacked by targeting invariant essential proteins. Here, we describe selective and potent inhibition of prolyl-tRNA synthetases (PRSs) from the above parasites using a series of quinazolinone-scaffold compounds. Our PRS-drug co-crystal structures reveal remarkable active site plasticity that accommodates diversely substituted compounds, an enzymatic feature that can be leveraged for refining drug-like properties of quinazolinones on a per parasite basis. A compound we termed In-5 exhibited a unique double conformation, enhanced drug-like properties, and cleared malaria in mice. It thus represents a new lead for optimization. Collectively, our data offer insights into the structure-guided optimization of quinazolinone-based compounds for drug development against multiple human eukaryotic pathogens.
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Rayevsky AV, Sharifi M, Tukalo MA. Molecular modeling and molecular dynamics simulation study of archaeal leucyl-tRNA synthetase in complex with different mischarged tRNA in editing conformation. J Mol Graph Model 2017; 76:289-295. [PMID: 28743072 DOI: 10.1016/j.jmgm.2017.06.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 06/07/2017] [Accepted: 06/23/2017] [Indexed: 12/20/2022]
Abstract
Aminoacyl-tRNA synthetases (aaRSs) play important roles in maintaining the accuracy of protein synthesis. Some aaRSs accomplish this via editing mechanisms, among which leucyl-tRNA synthetase (LeuRS) edits non-cognate amino acid norvaline mainly by post-transfer editing. However, the molecular basis for this pathway for eukaryotic and archaeal LeuRS remain unclear. In this study, a complex of archaeal P. horikoshii LeuRS (PhLeuRS) with misacylated tRNALeu was modeled wherever tRNA's acceptor stem was oriented directly into the editing site. To understand the distinctive features of organization we reconstructed a complex of PhLeuRS with tRNA and visualize post-transfer editing interactions mode by performing molecular dynamics (MD) simulation studies. To study molecular basis for substrate selectivity by PhLeuRS's editing site we utilized MD simulation of the entire LeuRS complexes using a diverse charged form of tRNAs, namely norvalyl-tRNALeu and isoleucyl-tRNALeu. In general, the editing site organization of LeuRS from P.horikoshii has much in common with bacterial LeuRS. The MD simulation results revealed that the post-transfer editing substrate norvalyl-A76, binds more strongly than isoleucyl-A76. Moreover, the branched side chain of isoleucine prevents water molecules from being closer and hence the hydrolysis reaction slows significantly. To investigate a possible mechanism of the post-transfer editing reaction, by PhLeuRS we have determined that two water molecules (the attacking and assisting water molecules) are localized near the carbonyl group of the amino acid to be cleaved off. These water molecules approach the substrate from the opposite side to that observed for Thermus thermophilus LeuRS (TtLeuRS). Based on the results obtained, it was suggested that the post-transfer editing mechanism of PhLeuRS differs from that of prokaryotic TtLeuRS.
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Affiliation(s)
- A V Rayevsky
- Institute of Molecular Biology and Genetics, NAS of Ukraine, 150 Academician Zabolotny Str., Kyiv 03680, Ukraine.
| | - M Sharifi
- Medway School of Pharmacy, Universities of Kent and Greenwich, Kent ME4 4TB, UK
| | - M A Tukalo
- Institute of Molecular Biology and Genetics, NAS of Ukraine, 150 Academician Zabolotny Str., Kyiv 03680, Ukraine.
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Jain V, Sharma A, Singh G, Yogavel M, Sharma A. Structure-Based Targeting of Orthologous Pathogen Proteins Accelerates Antiparasitic Drug Discovery. ACS Infect Dis 2017; 3:281-292. [PMID: 28195698 DOI: 10.1021/acsinfecdis.6b00181] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Parasitic diseases caused by eukaryotic pathogens impose significant health and economic burden worldwide. The level of research funding available for many parasitic diseases is insufficient in relation to their adverse social and economic impact. In this article, we discuss that extant 3D structural data on protein-inhibitor complexes can be harnessed to accelerate drug discovery against many related pathogens. Assessment of sequence conservation within drug/inhibitor-binding residues in enzyme-inhibitor complexes can be leveraged to predict and validate both new lead compounds and their molecular targets in multiple parasitic diseases. Hence, structure-based targeting of orthologous pathogen proteins accelerates the discovery of new antiparasitic drugs. This approach offers significant benefits for jumpstarting the discovery of new lead compounds and their molecular targets in diverse human, livestock, and plant pathogens.
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Affiliation(s)
- Vitul Jain
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Road, New Delhi 110067, India
| | - Arvind Sharma
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Road, New Delhi 110067, India
| | - Gajinder Singh
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Road, New Delhi 110067, India
| | - Manickam Yogavel
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Road, New Delhi 110067, India
| | - Amit Sharma
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Road, New Delhi 110067, India
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Moen SO, Edwards TE, Dranow DM, Clifton MC, Sankaran B, Van Voorhis WC, Sharma A, Manoil C, Staker BL, Myler PJ, Lorimer DD. Ligand co-crystallization of aminoacyl-tRNA synthetases from infectious disease organisms. Sci Rep 2017; 7:223. [PMID: 28303005 PMCID: PMC5428304 DOI: 10.1038/s41598-017-00367-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 02/20/2017] [Indexed: 12/15/2022] Open
Abstract
Aminoacyl-tRNA synthetases (aaRSs) charge tRNAs with their cognate amino acid, an essential precursor step to loading of charged tRNAs onto the ribosome and addition of the amino acid to the growing polypeptide chain during protein synthesis. Because of this important biological function, aminoacyl-tRNA synthetases have been the focus of anti-infective drug development efforts and two aaRS inhibitors have been approved as drugs. Several researchers in the scientific community requested aminoacyl-tRNA synthetases to be targeted in the Seattle Structural Genomics Center for Infectious Disease (SSGCID) structure determination pipeline. Here we investigate thirty-one aminoacyl-tRNA synthetases from infectious disease organisms by co-crystallization in the presence of their cognate amino acid, ATP, and/or inhibitors. Crystal structures were determined for a CysRS from Borrelia burgdorferi bound to AMP, GluRS from Borrelia burgdorferi and Burkholderia thailandensis bound to glutamic acid, a TrpRS from the eukaryotic pathogen Encephalitozoon cuniculi bound to tryptophan, a HisRS from Burkholderia thailandensis bound to histidine, and a LysRS from Burkholderia thailandensis bound to lysine. Thus, the presence of ligands may promote aaRS crystallization and structure determination. Comparison with homologous structures shows conformational flexibility that appears to be a recurring theme with this enzyme class.
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Affiliation(s)
- Spencer O Moen
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Bethesda, MD, USA.,Beryllium Discovery Corp, Bainbridge Island, WA, 98110, USA
| | - Thomas E Edwards
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Bethesda, MD, USA. .,Beryllium Discovery Corp, Bainbridge Island, WA, 98110, USA.
| | - David M Dranow
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Bethesda, MD, USA.,Beryllium Discovery Corp, Bainbridge Island, WA, 98110, USA
| | - Matthew C Clifton
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Bethesda, MD, USA.,Beryllium Discovery Corp, Bainbridge Island, WA, 98110, USA
| | - Banumathi Sankaran
- Berkeley Center for Structural Biology, Advanced Light Source, Berkeley, CA, 94720, USA
| | - Wesley C Van Voorhis
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Bethesda, MD, USA.,University of Washington, Seattle, WA, 98195-6423, USA
| | - Amit Sharma
- International Center for Genetic Engineering and Biotechnology, New Delhi, 110 067, India
| | - Colin Manoil
- University of Washington, Department of Genome Sciences, Seattle, WA, 98195-5065, USA
| | - Bart L Staker
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Bethesda, MD, USA.,Center for Infectious Disease Research (formerly Seattle Biomedical Research Institute), Seattle, WA, 98109, USA
| | - Peter J Myler
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Bethesda, MD, USA.,Center for Infectious Disease Research (formerly Seattle Biomedical Research Institute), Seattle, WA, 98109, USA.,University of Washington, Department of Medical Education and Biomedical Informatics & Department of Global Health, Seattle, WA, 98195, USA
| | - Donald D Lorimer
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Bethesda, MD, USA.,Beryllium Discovery Corp, Bainbridge Island, WA, 98110, USA
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Tsuchida K, Tsujita T, Hayashi M, Ojima A, Keleku-Lukwete N, Katsuoka F, Otsuki A, Kikuchi H, Oshima Y, Suzuki M, Yamamoto M. Halofuginone enhances the chemo-sensitivity of cancer cells by suppressing NRF2 accumulation. Free Radic Biol Med 2017; 103:236-247. [PMID: 28039084 DOI: 10.1016/j.freeradbiomed.2016.12.041] [Citation(s) in RCA: 101] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 12/23/2016] [Accepted: 12/27/2016] [Indexed: 12/30/2022]
Abstract
The KEAP1-NRF2 system regulates the cellular defence against oxidative and xenobiotic stresses. NRF2 is a transcription factor that activates the expression of cytoprotective genes encoding antioxidative, detoxifying and metabolic enzymes as well as transporters. Under normal conditions, KEAP1 represses NRF2 activity by degrading the NRF2 protein. When cells are exposed to stresses, KEAP1 stops promoting NRF2 degradation, and NRF2 rapidly accumulates and activates the transcription of target genes. Constitutive accumulation of NRF2 via a variety of mechanisms that disrupt KEAP1-mediated NRF2 degradation has been observed in various cancer types. Constitutive NRF2 accumulation confers cancer cells with a proliferative advantage as well as resistance to anti-cancer drugs and radiotherapies. To suppress the chemo- and radio-resistance of cancer cells caused by NRF2 accumulation, we conducted high-throughput chemical library screening for NRF2 inhibitors and identified febrifugine derivatives. We found that application of the less-toxic derivative halofuginone in a low dose range rapidly reduced NRF2 protein levels. Halofuginone induced a cellular amino acid starvation response that repressed global protein synthesis and rapidly depleted NRF2. Halofuginone treatment ameliorated the resistance of NRF2-addicted cancer cells to anti-cancer drugs both in vitro and in vivo. These results provide preclinical proof-of-concept evidence for halofuginone as an NRF2 inhibitor applicable to treatment of chemo- and radio-resistant forms of cancer.
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Affiliation(s)
- Kouhei Tsuchida
- Department of Medical Biochemistry, Tohoku University Graduate School of Medicine, Sendai 980-8575, Japan
| | - Tadayuki Tsujita
- Department of Medical Biochemistry, Tohoku University Graduate School of Medicine, Sendai 980-8575, Japan; Department of Applied Biochemistry and Food Science, Saga University, Saga 840-8502, Japan
| | - Makiko Hayashi
- Department of Medical Biochemistry, Tohoku University Graduate School of Medicine, Sendai 980-8575, Japan
| | - Asaka Ojima
- Department of Medical Biochemistry, Tohoku University Graduate School of Medicine, Sendai 980-8575, Japan
| | - Nadine Keleku-Lukwete
- Department of Medical Biochemistry, Tohoku University Graduate School of Medicine, Sendai 980-8575, Japan
| | - Fumiki Katsuoka
- Tohoku Medical Megabank Organization, Tohoku University, Sendai 980-8573, Japan
| | - Akihito Otsuki
- Division of Medical Biochemistry, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai 981-8558, Japan
| | - Haruhisa Kikuchi
- Laboratory of Natural Product Chemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai 980-8578, Japan
| | - Yoshiteru Oshima
- Laboratory of Natural Product Chemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai 980-8578, Japan
| | - Mikiko Suzuki
- Center for Radioisotope Sciences, Tohoku University Graduate School of Medicine, Sendai 980-8575, Japan.
| | - Masayuki Yamamoto
- Department of Medical Biochemistry, Tohoku University Graduate School of Medicine, Sendai 980-8575, Japan; Tohoku Medical Megabank Organization, Tohoku University, Sendai 980-8573, Japan.
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Montazeri M, Sharif M, Sarvi S, Mehrzadi S, Ahmadpour E, Daryani A. A Systematic Review of In vitro and In vivo Activities of Anti -Toxoplasma Drugs and Compounds (2006-2016). Front Microbiol 2017; 8:25. [PMID: 28163699 PMCID: PMC5247447 DOI: 10.3389/fmicb.2017.00025] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 01/05/2017] [Indexed: 11/23/2022] Open
Abstract
The currently available anti-Toxoplasma agents have serious limitations. This systematic review was performed to evaluate drugs and new compounds used for the treatment of toxoplasmosis. Data was systematically collected from published papers on the efficacy of drugs/compounds used against Toxoplasma gondii (T. gondii) globally during 2006-2016. The searched databases were PubMed, Google Scholar, Science Direct, ISI Web of Science, EBSCO, and Scopus. One hundred and eighteen papers were eligible for inclusion in this systematic review, which were both in vitro and in vivo studies. Within this review, 80 clinically available drugs and a large number of new compounds with more than 39 mechanisms of action were evaluated. Interestingly, many of the drugs/compounds evaluated against T. gondii act on the apicoplast. Therefore, the apicoplast represents as a potential drug target for new chemotherapy. Based on the current findings, 49 drugs/compounds demonstrated in vitro half-maximal inhibitory concentration (IC50) values of below 1 μM, but most of them were not evaluated further for in vivo effectiveness. However, the derivatives of the ciprofloxacin, endochin-like quinolones and 1-[4-(4-nitrophenoxy) phenyl] propane-1-one (NPPP) were significantly active against T. gondii tachyzoites both in vitro and in vivo. Thus, these compounds are promising candidates for future studies. Also, compound 32 (T. gondii calcium-dependent protein kinase 1 inhibitor), endochin-like quinolones, miltefosine, rolipram abolish, and guanabenz can be repurposed into an effective anti-parasitic with a unique ability to reduce brain tissue cysts (88.7, 88, 78, 74, and 69%, respectively). Additionally, no promising drugs are available for congenital toxoplasmosis. In conclusion, as current chemotherapy against toxoplasmosis is still not satisfactory, development of well-tolerated and safe specific immunoprophylaxis in relaxing the need of dependence on chemotherapeutics is a highly valuable goal for global disease control. However, with the increasing number of high-risk individuals, and absence of a proper vaccine, continued efforts are necessary for the development of novel treatment options against T. gondii. Some of the novel compounds reviewed here may represent good starting points for the discovery of effective new drugs. In further, bioinformatic and in silico studies are needed in order to identify new potential toxoplasmicidal drugs.
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Affiliation(s)
- Mahbobeh Montazeri
- Toxoplasmosis Research Center, Mazandaran University of Medical SciencesSari, Iran
- Student Research Committee, Mazandaran University of Medical SciencesSari, Iran
| | - Mehdi Sharif
- Toxoplasmosis Research Center, Mazandaran University of Medical SciencesSari, Iran
- Department of Parasitology and Mycology, Sari Medical School, Mazandaran University of Medical SciencesSari, Iran
| | - Shahabeddin Sarvi
- Toxoplasmosis Research Center, Mazandaran University of Medical SciencesSari, Iran
- Department of Parasitology and Mycology, Sari Medical School, Mazandaran University of Medical SciencesSari, Iran
| | - Saeed Mehrzadi
- Department of Pharmacology, School of Medicine, Iran University of Medical Sciences TehranIran
| | - Ehsan Ahmadpour
- Drug Applied Research Center, Tabriz University of Medical SciencesTabriz, Iran
| | - Ahmad Daryani
- Toxoplasmosis Research Center, Mazandaran University of Medical SciencesSari, Iran
- Department of Parasitology and Mycology, Sari Medical School, Mazandaran University of Medical SciencesSari, Iran
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Hewitt SN, Dranow DM, Horst BG, Abendroth JA, Forte B, Hallyburton I, Jansen C, Baragaña B, Choi R, Rivas KL, Hulverson MA, Dumais M, Edwards TE, Lorimer DD, Fairlamb AH, Gray DW, Read KD, Lehane AM, Kirk K, Myler PJ, Wernimont A, Walpole C, Stacy R, Barrett LK, Gilbert IH, Van Voorhis WC. Biochemical and Structural Characterization of Selective Allosteric Inhibitors of the Plasmodium falciparum Drug Target, Prolyl-tRNA-synthetase. ACS Infect Dis 2017; 3:34-44. [PMID: 27798837 PMCID: PMC5241706 DOI: 10.1021/acsinfecdis.6b00078] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Plasmodium falciparum (Pf) prolyl-tRNA synthetase (ProRS) is one of the few chemical-genetically validated drug targets for malaria, yet highly selective inhibitors have not been described. In this paper, approximately 40,000 compounds were screened to identify compounds that selectively inhibit PfProRS enzyme activity versus Homo sapiens (Hs) ProRS. X-ray crystallography structures were solved for apo, as well as substrate- and inhibitor-bound forms of PfProRS. We identified two new inhibitors of PfProRS that bind outside the active site. These two allosteric inhibitors showed >100 times specificity for PfProRS compared to HsProRS, demonstrating this class of compounds could overcome the toxicity related to HsProRS inhibition by halofuginone and its analogues. Initial medicinal chemistry was performed on one of the two compounds, guided by the cocrystallography of the compound with PfProRS, and the results can instruct future medicinal chemistry work to optimize these promising new leads for drug development against malaria.
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Affiliation(s)
- Stephen Nakazawa Hewitt
- Center for Emerging
and Reemerging Infectious Disease (CERID), University of Washington, 750 Republican Street, Seattle, Washington 98109, United States
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
| | - David M. Dranow
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
- Beryllium Discovery Corporation, 7869 N.E. Day Road West, Bainbridge Island, Washington 98110, United States
| | - Benjamin G. Horst
- Center for Emerging
and Reemerging Infectious Disease (CERID), University of Washington, 750 Republican Street, Seattle, Washington 98109, United States
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
| | - Jan A. Abendroth
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
- Beryllium Discovery Corporation, 7869 N.E. Day Road West, Bainbridge Island, Washington 98110, United States
| | - Barbara Forte
- Drug Discovery Unit (DDU), Division of Biological Chemistry and Drug
Discovery, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Irene Hallyburton
- Drug Discovery Unit (DDU), Division of Biological Chemistry and Drug
Discovery, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Chimed Jansen
- Drug Discovery Unit (DDU), Division of Biological Chemistry and Drug
Discovery, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Beatriz Baragaña
- Drug Discovery Unit (DDU), Division of Biological Chemistry and Drug
Discovery, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Ryan Choi
- Center for Emerging
and Reemerging Infectious Disease (CERID), University of Washington, 750 Republican Street, Seattle, Washington 98109, United States
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
| | - Kasey L. Rivas
- Center for Emerging
and Reemerging Infectious Disease (CERID), University of Washington, 750 Republican Street, Seattle, Washington 98109, United States
| | - Matthew A. Hulverson
- Center for Emerging
and Reemerging Infectious Disease (CERID), University of Washington, 750 Republican Street, Seattle, Washington 98109, United States
| | - Mitchell Dumais
- Center for Emerging
and Reemerging Infectious Disease (CERID), University of Washington, 750 Republican Street, Seattle, Washington 98109, United States
| | - Thomas E. Edwards
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
- Beryllium Discovery Corporation, 7869 N.E. Day Road West, Bainbridge Island, Washington 98110, United States
| | - Donald D. Lorimer
- Beryllium Discovery Corporation, 7869 N.E. Day Road West, Bainbridge Island, Washington 98110, United States
| | - Alan H. Fairlamb
- Drug Discovery Unit (DDU), Division of Biological Chemistry and Drug
Discovery, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - David W. Gray
- Drug Discovery Unit (DDU), Division of Biological Chemistry and Drug
Discovery, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Kevin D. Read
- Drug Discovery Unit (DDU), Division of Biological Chemistry and Drug
Discovery, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Adele M. Lehane
- Research School of Biology, The Australian National University, Acton, Australian Capital Territory 2601, Australia
| | - Kiaran Kirk
- Research School of Biology, The Australian National University, Acton, Australian Capital Territory 2601, Australia
| | - Peter J. Myler
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
- Center for Infectious Disease Research, 307 Westlake Avenue North, Suite 500, Seattle, Washington 98109, United States
- Departments of Global Health and Biomedical
Informatics and Medical Education, University of Washington, Seattle, Washington 98195, United States
| | - Amy Wernimont
- Structure-guided Drug Discovery Coalition (SDDC), Structural Genomic Consortium, 101 College Street, MaRS South Tower, Suite 700, Toronto, Ontario M5G 1L7, Canada
| | - Chris Walpole
- Structure-guided Drug Discovery Coalition (SDDC), Structural Genomic Consortium, 101 College Street, MaRS South Tower, Suite 700, Toronto, Ontario M5G 1L7, Canada
| | - Robin Stacy
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
- Center for Infectious Disease Research, 307 Westlake Avenue North, Suite 500, Seattle, Washington 98109, United States
| | - Lynn K. Barrett
- Center for Emerging
and Reemerging Infectious Disease (CERID), University of Washington, 750 Republican Street, Seattle, Washington 98109, United States
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
| | - Ian H. Gilbert
- Drug Discovery Unit (DDU), Division of Biological Chemistry and Drug
Discovery, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Wesley C. Van Voorhis
- Center for Emerging
and Reemerging Infectious Disease (CERID), University of Washington, 750 Republican Street, Seattle, Washington 98109, United States
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
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Jain V, Sharma A. Repurposing of Potent Drug Candidates for Multiparasite Targeting. Trends Parasitol 2017; 33:158-161. [PMID: 28081985 DOI: 10.1016/j.pt.2016.12.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 12/07/2016] [Accepted: 12/08/2016] [Indexed: 12/20/2022]
Abstract
Parasite-directed drug discovery efforts require sustained and substantial scientific resources. Many eukaryotic parasites share similarities in metabolic pathways and housekeeping genes, as evident from their underlying protein sequences. Their subsequent structural congruence within enzyme active sites can thus be leveraged for multiparasite targeting using similar or identical drug probes. This bodes well for delivering new anti-infectives.
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Affiliation(s)
- Vitul Jain
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Road, New Delhi 110067, India
| | - Amit Sharma
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Road, New Delhi 110067, India.
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Targeting Protein Translation in Organelles of the Apicomplexa. Trends Parasitol 2016; 32:953-965. [DOI: 10.1016/j.pt.2016.09.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 09/21/2016] [Accepted: 09/23/2016] [Indexed: 12/15/2022]
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Sharma A, Sharma M, Yogavel M, Sharma A. Protein Translation Enzyme lysyl-tRNA Synthetase Presents a New Target for Drug Development against Causative Agents of Loiasis and Schistosomiasis. PLoS Negl Trop Dis 2016; 10:e0005084. [PMID: 27806050 PMCID: PMC5091859 DOI: 10.1371/journal.pntd.0005084] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 09/30/2016] [Indexed: 12/14/2022] Open
Abstract
Helminth parasites are an assemblage of two major phyla of nematodes (also known as roundworms) and platyhelminths (also called flatworms). These parasites are a major human health burden, and infections caused by helminths are considered under neglected tropical diseases (NTDs). These infections are typified by limited clinical treatment options and threat of drug resistance. Aminoacyl-tRNA synthetases (aaRSs) are vital enzymes that decode genetic information and enable protein translation. The specific inhibition of pathogen aaRSs bores well for development of next generation anti-parasitics. Here, we have identified and annotated aaRSs and accessory proteins from Loa loa (nematode) and Schistosoma mansoni (flatworm) to provide a glimpse of these protein translation enzymes within these parasites. Using purified parasitic lysyl-tRNA synthetases (KRSs), we developed series of assays that address KRS enzymatic activity, oligomeric states, crystal structure and inhibition profiles. We show that L. loa and S. mansoni KRSs are potently inhibited by the fungal metabolite cladosporin. Our co-crystal structure of Loa loa KRS-cladosporin complex reveals key interacting residues and provides a platform for structure-based drug development. This work hence provides a new direction for both novel target discovery and inhibitor development against eukaryotic pathogens that include L. loa and S. mansoni.
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Affiliation(s)
- Arvind Sharma
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Manmohan Sharma
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Manickam Yogavel
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Amit Sharma
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
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Cryptosporidium and Toxoplasma Parasites Are Inhibited by a Benzoxaborole Targeting Leucyl-tRNA Synthetase. Antimicrob Agents Chemother 2016; 60:5817-27. [PMID: 27431220 PMCID: PMC5038320 DOI: 10.1128/aac.00873-16] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 07/07/2016] [Indexed: 11/20/2022] Open
Abstract
The apicomplexan parasites Cryptosporidium and Toxoplasma are serious threats to human health. Cryptosporidiosis is a severe diarrheal disease in malnourished children and immunocompromised individuals, with the only FDA-approved drug treatment currently being nitazoxanide. The existing therapies for toxoplasmosis, an important pathology in immunocompromised individuals and pregnant women, also have serious limitations. With the aim of developing alternative therapeutic options to address these health problems, we tested a number of benzoxaboroles, boron-containing compounds shown to be active against various infectious agents, for inhibition of the growth of Cryptosporidium parasites in mammalian cells. A 3-aminomethyl benzoxaborole, AN6426, with activity in the micromolar range and with activity comparable to that of nitazoxanide, was identified and further characterized using biophysical measurements of affinity and crystal structures of complexes with the editing domain of Cryptosporidium leucyl-tRNA synthetase (LeuRS). The same compound was shown to be active against Toxoplasma parasites, with the activity being enhanced in the presence of norvaline, an amino acid that can be mischarged by LeuRS. Our observations are consistent with AN6426 inhibiting protein synthesis in both Cryptosporidium and Toxoplasma by forming a covalent adduct with tRNA(Leu) in the LeuRS editing active site and suggest that further exploitation of the benzoxaborole scaffold is a valid strategy to develop novel, much needed antiparasitic agents.
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Dimerization of Arginyl-tRNA Synthetase by Free Heme Drives Its Inactivation in Plasmodium falciparum. Structure 2016; 24:1476-87. [PMID: 27502052 DOI: 10.1016/j.str.2016.06.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 06/15/2016] [Accepted: 06/20/2016] [Indexed: 11/23/2022]
Abstract
Excess cellular heme is toxic, and malaria parasites regulate its levels during hemoglobin digestion. Aminoacyl-tRNA synthetases are ubiquitous enzymes, and of these, arginyl-tRNA synthetase (RRS) is unique as its enzymatic product of charged tRNA is required for protein synthesis and degradation. We show that Plasmodium falciparum arginyl-tRNA synthetase (PfRRS) is an active, cytosolic, and monomeric enzyme. Its high-resolution crystal structure highlights critical structural differences with the human enzyme. We further show that hemin binds to and inhibits the aminoacylation activity of PfRRS. Hemin induces a dimeric form of PfRRS that is thus rendered enzymatically dead as it is unable to recognize its cognate tRNA(arg). Excessive hemin in chloroquine-treated malaria parasites results in significantly reduced charged tRNA(arg) levels, thus suggesting deceleration of protein synthesis. These data together suggest that the inhibition of Plasmodium falciparum arginyl-tRNA synthetase can now be synergized with existing antimalarials for more potent drug cocktails against malaria parasites.
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Kim HJ, Kang CH, Jayasooriya RGPT, Dilshara MG, Lee S, Choi YH, Seo YT, Kim GY. Hydrangenol inhibits lipopolysaccharide-induced nitric oxide production in BV2 microglial cells by suppressing the NF-κB pathway and activating the Nrf2-mediated HO-1 pathway. Int Immunopharmacol 2016; 35:61-69. [DOI: 10.1016/j.intimp.2016.03.022] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 03/15/2016] [Accepted: 03/17/2016] [Indexed: 12/16/2022]
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Leesombun A, Boonmasawai S, Shimoda N, Nishikawa Y. Effects of Extracts from Thai Piperaceae Plants against Infection with Toxoplasma gondii. PLoS One 2016; 11:e0156116. [PMID: 27213575 PMCID: PMC4877092 DOI: 10.1371/journal.pone.0156116] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 05/08/2016] [Indexed: 11/18/2022] Open
Abstract
Herbal medicines and natural herb extracts are widely used as alternative treatments for various parasitic diseases, and such extracts may also have potential to decrease the side effects of the standard regimen drugs used to treat toxoplasmosis (sulfadiazine-pyrimethamine combination). We evaluated how effective the Thai piperaceae plants Piper betle, P. nigrum and P. sarmentosum are against Toxoplasma gondii infection in vitro and in vivo. Individually, we extracted the piperaceae plants with ethanol, passed them through a rotary evaporator and then lyophilized them to obtain crude extracts for each one. The in vitro study indicated that the P. betle extract was the most effective extract at inhibiting parasite growth in HFF cells (IC50 on RH-GFP: 23.2 μg/mL, IC50 on PLK-GFP: 21.4 μg/mL). Furthermore, treatment of experimental mice with the P. betle extract for 7 days after infection with 1,000 tachyzoites of the T. gondii PLK strain increased their survival (survival rates: 100% in 400 mg/kg-treated, 83.3% in 100 mg/kg-treated, 33.3% in 25 mg/kg-treated, 33.3% in untreated mice). Furthermore, treatment with 400 mg/kg of the P. betle extract resulted in 100% mouse survival following infection with 100,000 tachyzoites. The present study shows that P. betle extract has the potential to act as a medical plant for the treatment of toxoplasmosis.
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Affiliation(s)
- Arpron Leesombun
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080–8555, Japan
| | - Sookruetai Boonmasawai
- Department of Preclinic and Applied Animal Science, Faculty of Veterinary Science, Mahidol University, 999 Phutthamonthon Sai 4 Road Salaya, Phutthamonthon Nakhonpathom 73170, Thailand
| | - Naomi Shimoda
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080–8555, Japan
| | - Yoshifumi Nishikawa
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080–8555, Japan
- * E-mail:
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Khan S. Recent advances in the biology and drug targeting of malaria parasite aminoacyl-tRNA synthetases. Malar J 2016; 15:203. [PMID: 27068331 PMCID: PMC4828885 DOI: 10.1186/s12936-016-1247-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 03/30/2016] [Indexed: 11/22/2022] Open
Abstract
Escalating drug resistance in malaria parasites and lack of vaccine entails the discovery of novel drug targets and inhibitor molecules. The multi-component protein translation machinery is a rich source of such drug targets. Malaria parasites contain three translational compartments: the cytoplasm, apicoplast and mitochondrion, of which the latter two are of the prokaryotic type. Recent explorations by many groups into the malaria parasite protein translation enzymes, aminoacyl-tRNA synthetases (aaRSs), have yielded many promising inhibitors. The understanding of the biology of this unique set of 36 enzymes has become much clearer in recent times. Current review discusses the advances made in understanding of crucial aaRSs from Plasmodium and also the specific inhibitors found against malaria aaRSs.
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Affiliation(s)
- Sameena Khan
- Drug Discovery Research Centre, Translational Health Science and Technology Institute (THSTI), NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, PO box #04, Faridabad, 121001, India.
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77
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Structural and functional attributes of malaria parasite diadenosine tetraphosphate hydrolase. Sci Rep 2016; 6:19981. [PMID: 26829485 PMCID: PMC4734340 DOI: 10.1038/srep19981] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 12/15/2015] [Indexed: 11/09/2022] Open
Abstract
Malaria symptoms are driven by periodic multiplication cycles of Plasmodium parasites in human red blood corpuscles (RBCs). Malaria infection still accounts for ~600,000 annual deaths, and hence discovery of both new drug targets and drugs remains vital. In the present study, we have investigated the malaria parasite enzyme diadenosine tetraphosphate (Ap4A) hydrolase that regulates levels of signalling molecules like Ap4A by hydrolyzing them to ATP and AMP. We have tracked the spatial distribution of parasitic Ap4A hydrolase in infected RBCs, and reveal its unusual localization on the infected RBC membrane in subpopulation of infected cells. Interestingly, enzyme activity assays reveal an interaction between Ap4A hydrolase and the parasite growth inhibitor suramin. We also present a high resolution crystal structure of Ap4A hydrolase in apo- and sulphate- bound state, where the sulphate resides in the enzyme active site by mimicking the phosphate of substrates like Ap4A. The unexpected infected erythrocyte localization of the parasitic Ap4A hydrolase hints at a possible role of this enzyme in purinerigic signaling. In addition, atomic structure of Ap4A hydrolase provides insights for selective drug targeting.
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78
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Cochrane RVK, Norquay AK, Vederas JC. Natural products and their derivatives as tRNA synthetase inhibitors and antimicrobial agents. MEDCHEMCOMM 2016. [DOI: 10.1039/c6md00274a] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The tRNA synthetase enzymes are promising targets for development of therapeutic agents against infections by parasitic protozoans (e.g. malaria), fungi and yeast, as well as bacteria resistant to current antibiotics.
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Affiliation(s)
| | - A. K. Norquay
- Department of Chemistry
- University of Alberta
- Edmonton
- T6G 2G2 Canada
| | - J. C. Vederas
- Department of Chemistry
- University of Alberta
- Edmonton
- T6G 2G2 Canada
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79
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Zaidan RK, Smullen S, Evans P. Asymmetric synthesis of (+)- and (−)-deoxyfebrifugine and deoxyhalofuginone. Tetrahedron Lett 2015. [DOI: 10.1016/j.tetlet.2015.09.146] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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80
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Natural products as probes in pharmaceutical research. J Ind Microbiol Biotechnol 2015; 43:249-60. [PMID: 26438431 DOI: 10.1007/s10295-015-1691-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 09/16/2015] [Indexed: 10/23/2022]
Abstract
From the start of the pharmaceutical research natural products played a key role in drug discovery and development. Over time many discoveries of fundamental new biology were triggered by the unique biological activity of natural products. Unprecedented chemical structures, novel chemotypes, often pave the way to investigate new biology and to explore new pathways and targets. This review summarizes the recent results in the area with a focus on research done in the laboratories of Novartis Institutes for BioMedical Research. We aim to put the technological advances in target identification techniques in the context to the current revival of phenotypic screening and the increasingly complex biological questions related to drug discovery.
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81
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Clinically Available Medicines Demonstrating Anti-Toxoplasma Activity. Antimicrob Agents Chemother 2015; 59:7161-9. [PMID: 26392504 DOI: 10.1128/aac.02009-15] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Toxoplasma gondii is an apicomplexan parasite of humans and other mammals, including livestock and companion animals. While chemotherapeutic regimens, including pyrimethamine and sulfadiazine regimens, ameliorate acute or recrudescent disease such as toxoplasmic encephalitis or ocular toxoplasmosis, these drugs are often toxic to the host. Moreover, no approved options are available to treat infected women who are pregnant. Lastly, no drug regimen has shown the ability to eradicate the chronic stage of infection, which is characterized by chemoresistant intracellular cysts that persist for the life of the host. In an effort to promote additional chemotherapeutic options, we now evaluate clinically available drugs that have shown efficacy in disease models but which lack clinical case reports. Ideally, less-toxic treatments for the acute disease can be identified and developed, with an additional goal of cyst clearance from human and animal hosts.
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