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Singh N, Sharma A. India should invest in the expansion of genomic epidemiology for vector-borne diseases filariasis, malaria and visceral leishmaniasis that are targeted for elimination. IJID REGIONS 2024; 13:100453. [PMID: 39430599 PMCID: PMC11490900 DOI: 10.1016/j.ijregi.2024.100453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2024] [Revised: 09/10/2024] [Accepted: 09/11/2024] [Indexed: 10/22/2024]
Abstract
Genomic epidemiology (GE) is an integration of genomics and epidemiology. The field has evolved significantly in the past decade, enhancing our understanding of genetic susceptibility, drug resistance, disease transmission patterns, outbreak surveillance, and vaccine development. It employs an arsenal of advanced tools such as whole-genome sequencing and single-nucleotide polymorphisms for analysis, tracing pathogen evolution, mapping genetic variations, and tracking drug resistance. The role of GE in infectious disease management extends beyond outbreak control to routine public health practices, precision medicine, and determining treatment policies. The expansion of GE can significantly bolster global health defenses by effectively enabling the detection and response to emerging health threats. However, challenges such as sampling bias, data quality, integration, standardization of computational pipelines, and need for trained personnel remain. To tackle these challenges, we must invest in building capacity, improving infrastructure, providing training, and fostering collaborations between scientists and public health officials. Concerted efforts must focus on overcoming existing hurdles and promoting seamless integration of basic research into public health frameworks to fully realize its potential. It is timely for India to rapidly expand its base in GE to gain valuable insights into genetic variations and disease susceptibilities. This will provide a fillip towards eliminating the three dominant vector-borne diseases in India: filariasis, malaria, and visceral leishmaniasis.
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Affiliation(s)
- Nandini Singh
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Amit Sharma
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
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2
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Woodland JG, Horatscheck A, Soares de Melo C, Dziwornu GA, Taylor D. Another decade of antimalarial drug discovery: New targets, tools and molecules. PROGRESS IN MEDICINAL CHEMISTRY 2024; 63:161-234. [PMID: 39370241 DOI: 10.1016/bs.pmch.2024.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/08/2024]
Abstract
Malaria remains a devastating but preventable infectious disease that disproportionately affects the African continent. Emerging resistance to current frontline therapies means that not only are new treatments urgently required, but also novel validated antimalarial targets to circumvent cross-resistance. Fortunately, tremendous efforts have been made by the global drug discovery community over the past decade. In this chapter, we will highlight some of the antimalarial drug discovery and development programmes currently underway across the globe, charting progress in the identification of new targets and the development of new classes of drugs to prosecute them. These efforts have been complemented by the development of valuable tools to accelerate target validation such as the NOD scid gamma (NSG) humanized mouse efficacy model and progress in predictive modelling and open-source software. Among the medicinal chemistry programmes that have been conducted over the past decade are those targeting Plasmodium falciparum ATPase4 (ATP4) and acetyl-CoA synthetase (AcAS) as well as proteins disrupting parasite protein translation such as the aminoacyl-tRNA synthetases (aaRSs) and eukaryotic elongation factor 2 (eEF2). The benefits and challenges of targeting Plasmodium kinases will be examined, with a focus on Plasmodium cyclic GMP-dependent protein kinase (PKG), cyclin-dependent-like protein kinase 3 (CLK3) and phosphatidylinositol 4-kinase (PI4K). The chapter concludes with a survey of incipient drug discovery centres in Africa and acknowledges the value of recent international meetings in galvanizing and uniting the antimalarial drug discovery community.
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Affiliation(s)
- John G Woodland
- Holistic Drug Discovery and Development (H3D) Centre, University of Cape Town, Rondebosch, South Africa; South African Medical Research Council Drug Discovery and Development Research Unit, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - André Horatscheck
- Holistic Drug Discovery and Development (H3D) Centre, University of Cape Town, Rondebosch, South Africa
| | - Candice Soares de Melo
- Holistic Drug Discovery and Development (H3D) Centre, University of Cape Town, Rondebosch, South Africa
| | - Godwin A Dziwornu
- Holistic Drug Discovery and Development (H3D) Centre, University of Cape Town, Rondebosch, South Africa
| | - Dale Taylor
- Holistic Drug Discovery and Development (H3D) Centre, University of Cape Town, Rondebosch, South Africa.
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3
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Olotu F, Tali MBT, Chepsiror C, Sheik Amamuddy O, Boyom FF, Tastan Bishop Ö. Repurposing DrugBank compounds as potential Plasmodium falciparum class 1a aminoacyl tRNA synthetase multi-stage pan-inhibitors with a specific focus on mitomycin. Int J Parasitol Drugs Drug Resist 2024; 25:100548. [PMID: 38805932 PMCID: PMC11152978 DOI: 10.1016/j.ijpddr.2024.100548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2024] [Revised: 05/11/2024] [Accepted: 05/16/2024] [Indexed: 05/30/2024]
Abstract
Plasmodium falciparum aminoacyl tRNA synthetases (PfaaRSs) are potent antimalarial targets essential for proteome fidelity and overall parasite survival in every stage of the parasite's life cycle. So far, some of these proteins have been singly targeted yielding inhibitor compounds that have been limited by incidences of resistance which can be overcome via pan-inhibition strategies. Hence, herein, for the first time, we report the identification and in vitro antiplasmodial validation of Mitomycin (MMC) as a probable pan-inhibitor of class 1a (arginyl(A)-, cysteinyl(C), isoleucyl(I)-, leucyl(L), methionyl(M), and valyl(V)-) PfaaRSs which hypothetically may underlie its previously reported activity on the ribosomal RNA to inhibit protein translation and biosynthesis. We combined multiple in silico structure-based discovery strategies that first helped identify functional and druggable sites that were preferentially targeted by the compound in each of the plasmodial proteins: Ins1-Ins2 domain in Pf-ARS; anticodon binding domain in Pf-CRS; CP1-editing domain in Pf-IRS and Pf-MRS; C-terminal domain in Pf-LRS; and CP-core region in Pf-VRS. Molecular dynamics studies further revealed that MMC allosterically induced changes in the global structures of each protein. Likewise, prominent structural perturbations were caused by the compound across the functional domains of the proteins. More so, MMC induced systematic alterations in the binding of the catalytic nucleotide and amino acid substrates which culminated in the loss of key interactions with key active site residues and ultimate reduction in the nucleotide-binding affinities across all proteins, as deduced from the binding energy calculations. These altogether confirmed that MMC uniformly disrupted the structure of the target proteins and essential substrates. Further, MMC demonstrated IC50 < 5 μM against the Dd2 and 3D7 strains of parasite making it a good starting point for malarial drug development. We believe that findings from our study will be important in the current search for highly effective multi-stage antimalarial drugs.
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Affiliation(s)
- Fisayo Olotu
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry, Microbiology and Bioinformatics, Rhodes University, Makhanda, 6139, South Africa
| | - Mariscal Brice Tchatat Tali
- Antimicrobial & Biocontrol Agents Unit, Laboratory for Phytobiochemistry & Medicinal Plants Studies, Department of Biochemistry, Faculty of Science-University of Yaounde 1, P.O. Box 812, Yaounde, Cameroon; Advanced Research and Health Innovation Hub (ARHIH), Magzi Street, P.O. Box 812, Yaounde, Cameroon
| | - Curtis Chepsiror
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry, Microbiology and Bioinformatics, Rhodes University, Makhanda, 6139, South Africa
| | - Olivier Sheik Amamuddy
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry, Microbiology and Bioinformatics, Rhodes University, Makhanda, 6139, South Africa
| | - Fabrice Fekam Boyom
- Antimicrobial & Biocontrol Agents Unit, Laboratory for Phytobiochemistry & Medicinal Plants Studies, Department of Biochemistry, Faculty of Science-University of Yaounde 1, P.O. Box 812, Yaounde, Cameroon; Advanced Research and Health Innovation Hub (ARHIH), Magzi Street, P.O. Box 812, Yaounde, Cameroon
| | - Özlem Tastan Bishop
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry, Microbiology and Bioinformatics, Rhodes University, Makhanda, 6139, South Africa.
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4
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Shaw S, Cohn IS, Baptista RP, Xia G, Melillo B, Agyabeng-Dadzie F, Kissinger JC, Striepen B. Genetic crosses within and between species of Cryptosporidium. Proc Natl Acad Sci U S A 2024; 121:e2313210120. [PMID: 38147547 PMCID: PMC10769859 DOI: 10.1073/pnas.2313210120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 11/12/2023] [Indexed: 12/28/2023] Open
Abstract
Parasites and their hosts are engaged in reciprocal coevolution that balances competing mechanisms of virulence, resistance, and evasion. This often leads to host specificity, but genomic reassortment between different strains can enable parasites to jump host barriers and conquer new niches. In the apicomplexan parasite Cryptosporidium, genetic exchange has been hypothesized to play a prominent role in adaptation to humans. The sexual lifecycle of the parasite provides a potential mechanism for such exchange; however, the boundaries of Cryptosporidium sex are currently undefined. To explore this experimentally, we established a model for genetic crosses. Drug resistance was engineered using a mutated phenylalanyl tRNA synthetase gene and marking strains with this and the previously used Neo transgene enabled selection of recombinant progeny. This is highly efficient, and genomic recombination is evident and can be continuously monitored in real time by drug resistance, flow cytometry, and PCR mapping. Using this approach, multiple loci can now be modified with ease. We demonstrate that essential genes can be ablated by crossing a Cre recombinase driver strain with floxed strains. We further find that genetic crosses are also feasible between species. Crossing Cryptosporidium parvum, a parasite of cattle and humans, and Cryptosporidium tyzzeri a mouse parasite resulted in progeny with a recombinant genome derived from both species that continues to vigorously replicate sexually. These experiments have important fundamental and translational implications for the evolution of Cryptosporidium and open the door to reverse- and forward-genetic analysis of parasite biology and host specificity.
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Affiliation(s)
- Sebastian Shaw
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA19104
| | - Ian S. Cohn
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA19104
| | - Rodrigo P. Baptista
- Department of Medicine, Houston Methodist Research Institute, Houston, TX77030
| | - Guoqin Xia
- Department of Chemistry, Scripps Research, La Jolla, CA92037
| | - Bruno Melillo
- Department of Chemistry, Scripps Research, La Jolla, CA92037
- Chemical Biology and Therapeutics Science Program, Broad Institute, Cambridge, MA02142
| | | | - Jessica C. Kissinger
- Department of Genetics, University of Georgia, Athens, GA30602
- Center for Tropical and Emerging Global Diseases and Institute of Bioinformatics, University of Georgia, Athens, GA30602
| | - Boris Striepen
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA19104
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5
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Xie SC, Griffin MDW, Winzeler EA, Ribas de Pouplana L, Tilley L. Targeting Aminoacyl tRNA Synthetases for Antimalarial Drug Development. Annu Rev Microbiol 2023; 77:111-129. [PMID: 37018842 DOI: 10.1146/annurev-micro-032421-121210] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
Abstract
Infections caused by malaria parasites place an enormous burden on the world's poorest communities. Breakthrough drugs with novel mechanisms of action are urgently needed. As an organism that undergoes rapid growth and division, the malaria parasite Plasmodium falciparum is highly reliant on protein synthesis, which in turn requires aminoacyl-tRNA synthetases (aaRSs) to charge tRNAs with their corresponding amino acid. Protein translation is required at all stages of the parasite life cycle; thus, aaRS inhibitors have the potential for whole-of-life-cycle antimalarial activity. This review focuses on efforts to identify potent plasmodium-specific aaRS inhibitors using phenotypic screening, target validation, and structure-guided drug design. Recent work reveals that aaRSs are susceptible targets for a class of AMP-mimicking nucleoside sulfamates that target the enzymes via a novel reaction hijacking mechanism. This finding opens up the possibility of generating bespoke inhibitors of different aaRSs, providing new drug leads.
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Affiliation(s)
- Stanley C Xie
- Department of Biochemistry and Pharmacology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria, Australia; , ,
| | - Michael D W Griffin
- Department of Biochemistry and Pharmacology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria, Australia; , ,
| | - Elizabeth A Winzeler
- Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, California, USA;
| | - Lluis Ribas de Pouplana
- Institute for Research in Biomedicine, The Barcelona Institute of Science and Technology, Barcelona, Catalonia, Spain;
- Catalan Institution for Research and Advanced Studies, Barcelona, Catalonia, Spain
| | - Leann Tilley
- Department of Biochemistry and Pharmacology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria, Australia; , ,
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6
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Shaw S, Cohn IS, Baptista RP, Xia G, Melillo B, Agyabeng-Dadzie F, Kissinger JC, Striepen B. Genetic crosses within and between species of Cryptosporidium. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.04.551960. [PMID: 37577700 PMCID: PMC10418217 DOI: 10.1101/2023.08.04.551960] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Parasites and their hosts are engaged in rapid coevolution that balances competing mechanisms of virulence, resistance, and evasion. This often leads to host specificity, but genomic reassortment between different strains can enable parasites to jump host barriers and conquer new niches. In the apicomplexan parasite Cryptosporidium genetic exchange has been hypothesized to play a prominent role in adaptation to humans. The sexual lifecycle of the parasite provides a potential mechanism for such exchange; however, the boundaries of Cryptosporidium sex are currently undefined. To explore this experimentally, we established a model for genetic crosses. Drug resistance was engineered using a mutated phenylalanyl tRNA synthetase gene and marking strains with this and the previously used Neo transgene enabled selection of recombinant progeny. This is highly efficient, and genomic recombination is evident and can be continuously monitored in real time by drug resistance, flow cytometry, and PCR mapping. Using this approach multiple loci can now be modified with ease. We demonstrate that essential genes can be ablated by crossing a Cre recombinase driver strain with floxed strains. We further find that genetic crosses are also feasible between species. Crossing C. parvum, a parasite of cattle and humans, and C. tyzzeri a mouse parasite resulted in progeny with a recombinant genome derived from both species that continues to vigorously replicate sexually. These experiments have important fundamental and translational implications for the evolution of Cryptosporidium and open the door to reverse- and forward- genetic analysis of parasite biology and host specificity.
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Affiliation(s)
- Sebastian Shaw
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA
| | - Ian S. Cohn
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA
| | | | - Guoqin Xia
- Department of Chemistry, Scripps Research, La Jolla, CA
| | - Bruno Melillo
- Department of Chemistry, Scripps Research, La Jolla, CA
- Chemical Biology and Therapeutics Science Program, Broad Institute, Cambridge, MA
| | | | - Jessica C. Kissinger
- Department of Genetics, University of Georgia, Athens, GA
- Center for Tropical and Emerging Global Diseases and Institute of Bioinformatics University of Georgia, Athens, GA
| | - Boris Striepen
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA
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7
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Sharma VK, Chhibber-Goel J, Yogavel M, Sharma A. Structural characterization of glutamyl-tRNA synthetase (GluRS) from Plasmodium falciparum. Mol Biochem Parasitol 2023; 253:111530. [PMID: 36370911 DOI: 10.1016/j.molbiopara.2022.111530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Revised: 11/05/2022] [Accepted: 11/08/2022] [Indexed: 11/11/2022]
Abstract
Aminoacyl-tRNA synthetases (aaRSs) are essential enzymes in protein translation machinery that provide the charged tRNAs needed for protein synthesis. Over the past decades, aaRSs have been studied as anti-parasitic, anti-bacterial, and anti-fungal drug targets. This study focused on the cytoplasmic glutamyl-tRNA synthetase (GluRS) from Plasmodium falciparum, which belongs to class Ib in aaRSs. GluRS unlike most other aaRSs requires tRNA to activate its cognate amino acid substrate L-Glutamate (L-Glu), and fails to form an intermediate adenylate complex in the absence of tRNA. The crystal structures of the Apo, ATP, and ADP-bound forms of Plasmodium falciparum glutamyl-tRNA synthetase (PfGluRS) were solved at 2.1 Å, 2.2 Å, and 2.8 Å respectively. The structural comparison of the Apo- and ATP-bound holo-forms of PfGluRS showed considerable conformational changes in the loop regions around the ATP-binding pocket of the enzyme. Biophysical characterization of the PfGluRS showed binding of the enzyme substrates L-Gluand ATP.. The sequence and structural conservation were evident across GluRS compared to other species. The structural dissection of the PfGluRS gives insight into the critical residues involved in the binding of ATP substrate, which can be harvested to develop new antimalarial drugs.
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Affiliation(s)
- Vivek Kumar Sharma
- Molecular Medicine - Structural Parasitology, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India
| | - Jyoti Chhibber-Goel
- Molecular Medicine - Structural Parasitology, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India
| | - Manickam Yogavel
- Molecular Medicine - Structural Parasitology, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India
| | - Amit Sharma
- Molecular Medicine - Structural Parasitology, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India.
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8
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Gill J, Sharma A. Exploration of aminoacyl-tRNA synthetases from eukaryotic parasites for drug development. J Biol Chem 2022; 299:102860. [PMID: 36596362 PMCID: PMC9978631 DOI: 10.1016/j.jbc.2022.102860] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 12/26/2022] [Accepted: 12/27/2022] [Indexed: 01/01/2023] Open
Abstract
Parasitic diseases result in considerable human morbidity and mortality. The continuous emergence and spread of new drug-resistant parasite strains is an obstacle to controlling and eliminating many parasitic diseases. Aminoacyl-tRNA synthetases (aaRSs) are ubiquitous enzymes essential for protein synthesis. The design and development of diverse small molecule, drug-like inhibitors against parasite-encoded and expressed aaRSs have validated this enzyme family as druggable. In this work, we have compiled the progress to date towards establishing the druggability of aaRSs in terms of their biochemical characterization, validation as targets, inhibitor development, and structural interpretation from parasites responsible for malaria (Plasmodium), lymphatic filariasis (Brugia,Wuchereria bancrofti), giardiasis (Giardia), toxoplasmosis (Toxoplasma gondii), leishmaniasis (Leishmania), cryptosporidiosis (Cryptosporidium), and trypanosomiasis (Trypanosoma). This work thus provides a robust framework for the systematic dissection of aaRSs from these pathogens and will facilitate the cross-usage of potential inhibitors to jump-start anti-parasite drug development.
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Affiliation(s)
- Jasmita Gill
- ICMR-National Institute of Malaria Research, New Delhi, India
| | - Amit Sharma
- ICMR-National Institute of Malaria Research, New Delhi, India; Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.
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9
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Volynets GP, Gudzera OI, Usenko MO, Gorbatiuk OB, Yarmoluk SM, Tukalo MA. Probing interactions of aminoacyl-adenylate with Mycobacterium tuberculosis methionyl-tRNA synthetase through in silico site-directed mutagenesis and free energy calculation. J Biomol Struct Dyn 2022:1-9. [PMID: 35930324 DOI: 10.1080/07391102.2022.2107574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Methionyl-tRNA synthetase (MetRS) is an attractive molecular target for antibiotic discovery. Recently, we have developed several classes of small-molecular inhibitors of Mycobacterium tuberculosis MetRS possessing antibacterial activity. In this article, we performed in silico site-directed mutagenesis of aminoacyl-adenylate binding site of M. tuberculosis MetRS in order to identify crucial amino acid residues for substrate interaction. The umbrella sampling algorithm was used to calculate the binding free energy (ΔG) of these mutated forms with methionyl-adenylate analogue. According to the obtained results, the replacement of Glu24 and Leu293 by alanine leads to the most significant decrease in the binding free energy (ΔG) for adenylate analogue with methionyl-tRNA synthetase indicating increasing of the affinity, which in turn causes the loss of compounds inhibitory activity. Therefore, these amino acid residues can be proposed for further experimental site-directed mutagenesis to confirm binding mode of inhibitors and should be taken into account during chemical optimization to overcome resistance due to mutations.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Galyna P Volynets
- Department of Medicinal Chemistry, Institute of Molecular Biology and Genetics, the NAS of Ukraine, Kyiv, Ukraine
| | - Olga I Gudzera
- Department of Protein Synthesis Enzymology, Institute of Molecular Biology and Genetics, the NAS of Ukraine, Kyiv, Ukraine
| | - Mariia O Usenko
- Department of Cell Regulatory Mechanisms, Institute of Molecular Biology and Genetics, the NAS of Ukraine, Kyiv, Ukraine
| | - Oksana B Gorbatiuk
- Department of Cell Regulatory Mechanisms, Institute of Molecular Biology and Genetics, the NAS of Ukraine, Kyiv, Ukraine
| | - Sergiy M Yarmoluk
- Department of Medicinal Chemistry, Institute of Molecular Biology and Genetics, the NAS of Ukraine, Kyiv, Ukraine
| | - Michael A Tukalo
- Department of Protein Synthesis Enzymology, Institute of Molecular Biology and Genetics, the NAS of Ukraine, Kyiv, Ukraine
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10
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Jaramillo Ponce JR, Kapps D, Paulus C, Chicher J, Frugier M. Discovery of two distinct aminoacyl-tRNA synthetase complexes anchored to the Plasmodium surface tRNA import protein. J Biol Chem 2022; 298:101987. [PMID: 35487244 PMCID: PMC9136112 DOI: 10.1016/j.jbc.2022.101987] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 04/19/2022] [Accepted: 04/20/2022] [Indexed: 11/21/2022] Open
Abstract
Aminoacyl-tRNA synthetases (aaRSs) attach amino acids to their cognate transfer RNAs. In eukaryotes, a subset of cytosolic aaRSs is organized into a multisynthetase complex (MSC), along with specialized scaffolding proteins referred to as aaRS-interacting multifunctional proteins (AIMPs). In Plasmodium, the causative agent of malaria, the tRNA import protein (tRip), is a membrane protein that participates in tRNA trafficking; we show that tRip also functions as an AIMP. We identified three aaRSs, the glutamyl-tRNA synthetase (ERS), glutaminyl-tRNA synthetase (QRS), and methionyl-tRNA synthetase (MRS), which were specifically coimmunoprecipitated with tRip in Plasmodium berghei blood stage parasites. All four proteins contain an N-terminal glutathione-S-transferase (GST)-like domain that was demonstrated to be involved in MSC assembly. In contrast to previous studies, further dissection of GST-like interactions identified two exclusive heterotrimeric complexes: the Q-complex (tRip-ERS-QRS) and the M-complex (tRip-ERS-MRS). Gel filtration and light scattering suggest a 2:2:2 stoichiometry for both complexes but with distinct biophysical properties and mutational analysis further revealed that the GST-like domains of QRS and MRS use different strategies to bind ERS. Taken together, our results demonstrate that neither the singular homodimerization of tRip nor its localization in the parasite plasma membrane prevents the formation of MSCs in Plasmodium. Besides, the extracellular localization of the tRNA-binding module of tRip is compensated by the presence of additional tRNA-binding modules fused to MRS and QRS, providing each MSC with two spatially distinct functions: aminoacylation of intraparasitic tRNAs and binding of extracellular tRNAs. This unique host-pathogen interaction is discussed.
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Affiliation(s)
- José R Jaramillo Ponce
- Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR 9002, Strasbourg, France
| | - Delphine Kapps
- Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR 9002, Strasbourg, France
| | - Caroline Paulus
- Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR 9002, Strasbourg, France
| | - Johana Chicher
- Strasbourg-Esplanade Proteomics Facility, Université de Strasbourg, Strasbourg, France
| | - Magali Frugier
- Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR 9002, Strasbourg, France.
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11
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Inhibition of Plasmodium falciparum phenylalanine tRNA synthetase provides opportunity for antimalarial drug development. Structure 2022; 30:962-972.e3. [PMID: 35460612 DOI: 10.1016/j.str.2022.03.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 01/17/2022] [Accepted: 03/29/2022] [Indexed: 11/21/2022]
Abstract
Bicyclic azetidine compounds possess antimalarial activity via targeting of the cytoplasmic Plasmodium falciparum (Pf) protein translation enzyme phenylalanine-tRNA synthetase (cFRS). These drugs kill parasites both in vitro and in vivo, including the blood, liver, and transmission developmental stages. Here we present the co-crystal structure of PfcFRS with a potent inhibitor, the bicyclic azetidine BRD7929. Our studies reveal high-affinity binding of BRD7929 with PfcFRS along with exquisite specificity compared with the human enzyme, leading in turn to potent and selective inhibition of the parasite enzyme. Our co-crystal structure shows that BRD7929 binds in the active site in the α subunit of PfcFRS, where it occupies the amino acid site, an auxiliary site, and partially the ATP site. This structural snapshot of inhibitor-bound PfcFRS thus provides a platform for the structure-guided optimization of novel antimalarial compounds.
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12
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Transcriptome Analysis of the Marine Nematode Litoditis marina in a Chemically Defined Food Environment with Stearic Acid Supplementation. JOURNAL OF MARINE SCIENCE AND ENGINEERING 2022. [DOI: 10.3390/jmse10030428] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Stearic acid represents one of the most abundant fatty acids in the Western diet and profoundly regulates health and diseases of animals and human beings. We previously showed that stearic acid supplementation promoted development of the terrestrial model nematode Caenorhabditis elegans in chemically defined CeMM food environment. However, whether stearic acid regulates development of other nematodes remains unknown. Here, we found that dietary supplementation with stearic acid could promote the development of the marine nematode Litoditis marina, belonging to the same family as C. elegans, indicating the conserved roles of stearic acid in developmental regulation. We further employed transcriptome analysis to analyze genome-wide transcriptional signatures of L. marina with dietary stearic acid supplementation. We found that stearic acid might promote development of L. marina via upregulation of the expression of genes involved in aminoacyl-tRNA biosynthesis, translation initiation and elongation, ribosome biogenesis, and transmembrane transport. In addition, we observed that the expression of neuronal signaling-related genes was decreased. This study provided important insights into how a single fatty acid stearic acid regulates development of marine nematode, and further studies with CRISPR genome editing will facilitate demonstrating the molecular mechanisms underlying how a single metabolite regulates animal development and health.
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13
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Sparsomycin Exhibits Potent Antiplasmodial Activity In Vitro and In Vivo. Pharmaceutics 2022; 14:pharmaceutics14030544. [PMID: 35335918 PMCID: PMC8954220 DOI: 10.3390/pharmaceutics14030544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 02/20/2022] [Accepted: 02/26/2022] [Indexed: 02/04/2023] Open
Abstract
The emerging spread of drug-resistant malaria parasites highlights the need for new antimalarial agents. This study evaluated the growth-inhibitory effects of sparsomycin (Sm), a peptidyl transferase inhibitor, against Plasmodium falciparum 3D7 (chloroquine-sensitive strain), P. falciparum K1 (resistant to multiple drugs, including chloroquine), P. yoelii 17XNL (cause of uncomplicated rodent malaria) and P. berghei ANKA (cause of complicated rodent malaria). Using a fluorescence-based assay, we found that Sm exhibited half-maximal inhibitory concentrations (IC50) of 12.07 and 25.43 nM against P. falciparum 3D7 and K1, respectively. In vitro treatment of P. falciparum 3D7 with Sm at 10 or 50 nM induced morphological alteration, blocked parasites in the ring state and prevented erythrocyte reinvasion, even after removal of the compound. In mice infected with P. yoelii 17XNL, the administration of 100 μg/kg Sm for 7 days did not affect parasitemia. Meanwhile, treatment with 300 μg/kg Sm resulted in a significantly lower parasitemia peak (18.85%) than that observed in the control group (40.13%). In mice infected with P. berghei ANKA, both four and seven doses of Sm (300 μg/kg) prolonged survival by 33.33%. Our results indicate that Sm has potential antiplasmodial activities in vitro and in vivo, warranting its further development as an alternative treatment for malaria.
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14
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Rybak MY, Balanda AO, Yatsyshyna AP, Kotey IM, Starosyla SA, Bdzhola VG, Lukash LL, Yarmoluk SM, Tukalo MA, Volynets GP. Discovery of novel antituberculosis agents among 3-phenyl-5-(1-phenyl-1H-[1,2,3]triazol-4-yl)-[1,2,4]oxadiazole derivatives targeting aminoacyl-tRNA synthetases. Sci Rep 2021; 11:7162. [PMID: 33785838 PMCID: PMC8010095 DOI: 10.1038/s41598-021-86562-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 03/17/2021] [Indexed: 02/05/2023] Open
Abstract
Antibiotic resistance is a major problem of tuberculosis treatment. This provides the stimulus for the search of novel molecular targets and approaches to reduce or forestall resistance emergence in Mycobacterium tuberculosis. Earlier, we discovered a novel small-molecular inhibitor among 3-phenyl-5-(1-phenyl-1H-[1,2,3]triazol-4-yl)-[1,2,4]oxadiazoles targeting simultaneously two enzymes-mycobacterial leucyl-tRNA synthetase (LeuRS) and methionyl-tRNA synthetase (MetRS), which are promising molecular targets for antibiotic development. Unfortunately, the identified inhibitor does not reveal antibacterial activity toward M. tuberculosis. This study aims to develop novel aminoacyl-tRNA synthetase inhibitors among this chemical class with antibacterial activity toward resistant strains of M. tuberculosis. We performed molecular docking of the library of 3-phenyl-5-(1-phenyl-1H-[1,2,3]triazol-4-yl)-[1,2,4]oxadiazole derivatives and selected 41 compounds for investigation of their inhibitory activity toward MetRS and LeuRS in aminoacylation assay and antibacterial activity toward M. tuberculosis strains using microdilution assay. In vitro screening resulted in 10 compounds active against MetRS and 3 compounds active against LeuRS. Structure-related relationships (SAR) were established. The antibacterial screening revealed 4 compounds active toward M. tuberculosis mono-resistant strains in the range of concentrations 2-20 mg/L. Among these compounds, only one compound 27 has significant enzyme inhibitory activity toward mycobacterial MetRS (IC50 = 148.5 µM). The MIC for this compound toward M. tuberculosis H37Rv strain is 12.5 µM. This compound is not cytotoxic to human HEK293 and HepG2 cell lines. Therefore, 3-phenyl-5-(1-phenyl-1H-[1,2,3]triazol-4-yl)-[1,2,4]oxadiazole derivatives can be used for further chemical optimization and biological research to find non-toxic antituberculosis agents with a novel mechanism of action.
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Affiliation(s)
- Mariia Yu Rybak
- Department of Protein Synthesis Enzymology, Institute of Molecular Biology and Genetics of the NAS of Ukraine, Kyiv, Ukraine.
| | - Anatoliy O Balanda
- Department of Medicinal Chemistry, Institute of Molecular Biology and Genetics of the NAS of Ukraine, Kyiv, Ukraine
| | - Anna P Yatsyshyna
- Department of Human Genetics, Institute of Molecular Biology and Genetics of the NAS of Ukraine, Kyiv, Ukraine
| | - Igor M Kotey
- Department of Medicinal Chemistry, Institute of Molecular Biology and Genetics of the NAS of Ukraine, Kyiv, Ukraine
| | - Sergiy A Starosyla
- Department of Medicinal Chemistry, Institute of Molecular Biology and Genetics of the NAS of Ukraine, Kyiv, Ukraine
| | - Volodymyr G Bdzhola
- Department of Medicinal Chemistry, Institute of Molecular Biology and Genetics of the NAS of Ukraine, Kyiv, Ukraine
| | - Lubov L Lukash
- Department of Human Genetics, Institute of Molecular Biology and Genetics of the NAS of Ukraine, Kyiv, Ukraine
| | - Sergiy M Yarmoluk
- Department of Medicinal Chemistry, Institute of Molecular Biology and Genetics of the NAS of Ukraine, Kyiv, Ukraine
| | - Michael A Tukalo
- Department of Protein Synthesis Enzymology, Institute of Molecular Biology and Genetics of the NAS of Ukraine, Kyiv, Ukraine
| | - Galyna P Volynets
- Department of Medicinal Chemistry, Institute of Molecular Biology and Genetics of the NAS of Ukraine, Kyiv, Ukraine
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15
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Abstract
Aminoacyl-tRNA synthetases (AARSs) have been considered very attractive drug-targets for decades. This interest probably emerged with the identification of differences in AARSs between prokaryotic and eukaryotic species, which provided a rationale for the development of antimicrobials targeting bacterial AARSs with minimal effect on the homologous human AARSs. Today we know that AARSs are not only attractive, but also valid drug targets as they are housekeeping proteins that: (i) play a fundamental role in protein translation by charging the corresponding amino acid to its cognate tRNA and preventing mistranslation mistakes [1], a critical process during fast growing conditions of microbes; and (ii) present significant differences between microbes and humans that can be used for drug development [2]. Together with the vast amount of available data on both pathogenic and mammalian AARSs, it is expected that, in the future, the numerous reported inhibitors of AARSs will provide the basis to develop new therapeutics for the treatment of human diseases. In this chapter, a detailed summary on the state-of-the-art in drug discovery and drug development for each aminoacyl-tRNA synthetase will be presented.
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Affiliation(s)
- Maria Lukarska
- Institute for Advanced Biosciences (IAB), Structural Biology of Novel Drug Targets in Human Diseases, INSERM U1209, CNRS UMR 5309, University Grenoble Alpes, Grenoble, France
| | - Andrés Palencia
- Institute for Advanced Biosciences (IAB), Structural Biology of Novel Drug Targets in Human Diseases, INSERM U1209, CNRS UMR 5309, University Grenoble Alpes, Grenoble, France.
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16
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Vinayak S, Jumani RS, Miller P, Hasan MM, McLeod BI, Tandel J, Stebbins EE, Teixeira JE, Borrel J, Gonse A, Zhang M, Yu X, Wernimont A, Walpole C, Eckley S, Love MS, McNamara CW, Sharma M, Sharma A, Scherer CA, Kato N, Schreiber SL, Melillo B, Striepen B, Huston CD, Comer E. Bicyclic azetidines kill the diarrheal pathogen Cryptosporidium in mice by inhibiting parasite phenylalanyl-tRNA synthetase. Sci Transl Med 2020; 12:eaba8412. [PMID: 32998973 PMCID: PMC8381743 DOI: 10.1126/scitranslmed.aba8412] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Accepted: 09/11/2020] [Indexed: 12/21/2022]
Abstract
Cryptosporidium is a protozoan parasite and a leading cause of diarrheal disease and mortality in young children. Currently, there are no fully effective treatments available to cure infection with this diarrheal pathogen. In this study, we report a broad drug repositioning effort that led to the identification of bicyclic azetidines as a new anticryptosporidial series. Members of this series blocked growth in in vitro culture of three Cryptosporidium parvum isolates with EC50 's in 1% serum of <0.4 to 96 nM, had comparable potencies against Cryptosporidium hominis and C. parvum, and was effective in three of four highly susceptible immunosuppressed mice with once-daily dosing administered for 4 days beginning 2 weeks after infection. Comprehensive genetic, biochemical, and chemical studies demonstrated inhibition of C. parvum phenylalanyl-tRNA synthetase (CpPheRS) as the mode of action of this new lead series. Introduction of mutations directly into the C. parvum pheRS gene by CRISPR-Cas9 genome editing resulted in parasites showing high degrees of compound resistance. In vitro, bicyclic azetidines potently inhibited the aminoacylation activity of recombinant ChPheRS. Medicinal chemistry optimization led to the identification of an optimal pharmacokinetic/pharmacodynamic profile for this series. Collectively, these data demonstrate that bicyclic azetidines are a promising series for anticryptosporidial drug development and establish a broad framework to enable target-based drug discovery for this infectious disease.
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Affiliation(s)
- Sumiti Vinayak
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL 61802, USA
| | - Rajiv S Jumani
- Cellular, Molecular and Biomedical Sciences Graduate Program, University of Vermont, Burlington, VT 05405, USA
| | - Peter Miller
- Department of Medicine, Larner College of Medicine, University of Vermont, Burlington, VT 05405, USA
| | - Muhammad M Hasan
- Cellular, Molecular and Biomedical Sciences Graduate Program, University of Vermont, Burlington, VT 05405, USA
| | - Briana I McLeod
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jayesh Tandel
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Erin E Stebbins
- Department of Medicine, Larner College of Medicine, University of Vermont, Burlington, VT 05405, USA
| | - Jose E Teixeira
- Department of Medicine, Larner College of Medicine, University of Vermont, Burlington, VT 05405, USA
| | - Julien Borrel
- Chemical Biology and Therapeutics Science Program, Broad Institute, Cambridge, MA 02142, USA
| | - Arthur Gonse
- Chemical Biology and Therapeutics Science Program, Broad Institute, Cambridge, MA 02142, USA
| | - Mingliang Zhang
- International Discovery Service Unit, WuXi AppTec (Tianjin) Co. Ltd., Tianjin 300457, P.R. China
| | - Xianshui Yu
- International Discovery Service Unit, WuXi AppTec (Tianjin) Co. Ltd., Tianjin 300457, P.R. China
| | - Amy Wernimont
- Structural Genomics Consortium, MaRS Building, South Tower, 101 College Street, Suite 700, Toronto, Ontario M5G 1L7, Canada
| | - Chris Walpole
- Structural Genomics Consortium, MaRS Building, South Tower, 101 College Street, Suite 700, Toronto, Ontario M5G 1L7, Canada
| | | | - Melissa S Love
- Calibr, a division of The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Case W McNamara
- Calibr, a division of The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Manmohan Sharma
- Structural Parasitology, Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Road, New Delhi 110070, India
| | - Amit Sharma
- Structural Parasitology, Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Road, New Delhi 110070, India
| | - Christina A Scherer
- Chemical Biology and Therapeutics Science Program, Broad Institute, Cambridge, MA 02142, USA
| | - Nobutaka Kato
- Chemical Biology and Therapeutics Science Program, Broad Institute, Cambridge, MA 02142, USA
| | - Stuart L Schreiber
- Chemical Biology and Therapeutics Science Program, Broad Institute, Cambridge, MA 02142, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Bruno Melillo
- Chemical Biology and Therapeutics Science Program, Broad Institute, Cambridge, MA 02142, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Boris Striepen
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Christopher D Huston
- Department of Medicine, Larner College of Medicine, University of Vermont, Burlington, VT 05405, USA.
| | - Eamon Comer
- Chemical Biology and Therapeutics Science Program, Broad Institute, Cambridge, MA 02142, USA.
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17
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Clark RD, Morris DN, Chinigo G, Lawless MS, Prudhomme J, Le Roch KG, Lafuente MJ, Ferrer S, Gamo FJ, Gadwood R, Woltosz WS. Design and tests of prospective property predictions for novel antimalarial 2-aminopropylaminoquinolones. J Comput Aided Mol Des 2020; 34:1117-1132. [PMID: 32833084 PMCID: PMC7533260 DOI: 10.1007/s10822-020-00333-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 07/21/2020] [Indexed: 10/31/2022]
Abstract
There is a pressing need to improve the efficiency of drug development, and nowhere is that need more clear than in the case of neglected diseases like malaria. The peculiarities of pyrimidine metabolism in Plasmodium species make inhibition of dihydroorotate dehydrogenase (DHODH) an attractive target for antimalarial drug design. By applying a pair of complementary quantitative structure-activity relationships derived for inhibition of a truncated, soluble form of the enzyme from Plasmodium falciparum (s-PfDHODH) to data from a large-scale phenotypic screen against cultured parasites, we were able to identify a class of antimalarial leads that inhibit the enzyme and abolish parasite growth in blood culture. Novel analogs extending that class were designed and synthesized with a goal of improving potency as well as the general pharmacokinetic and toxicological profiles. Their synthesis also represented an opportunity to prospectively validate our in silico property predictions. The seven analogs synthesized exhibited physicochemical properties in good agreement with prediction, and five of them were more active against P. falciparum growing in blood culture than any of the compounds in the published lead series. The particular analogs prepared did not inhibit s-PfDHODH in vitro, but advanced biological assays indicated that other examples from the class did inhibit intact PfDHODH bound to the mitochondrial membrane. The new analogs, however, killed the parasites by acting through some other, unidentified mechanism 24-48 h before PfDHODH inhibition would be expected to do so.
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Affiliation(s)
- Robert D Clark
- Simulations Plus, Inc., 42505 10th Street West, Lancaster, CA, 93534-7059, USA.
| | - Denise N Morris
- Cognigen Corporation, a Simulations Plus Company, Buffalo, NY, USA
| | - Gary Chinigo
- Kalexsyn, Inc., Kalamazoo, MI, USA.,Pfizer Inc., Groton, CT, USA
| | - Michael S Lawless
- Simulations Plus, Inc., 42505 10th Street West, Lancaster, CA, 93534-7059, USA
| | - Jacques Prudhomme
- Department of Molecular, Cell and Systems Biology, University of California, Riverside, CA, USA
| | - Karine G Le Roch
- Department of Molecular, Cell and Systems Biology, University of California, Riverside, CA, USA
| | - Maria José Lafuente
- Tres Cantos Medicines Development Campus-Diseases of the Developing World, GlaxoSmithKline, Tres Cantos, Madrid, Spain
| | - Santiago Ferrer
- Tres Cantos Medicines Development Campus-Diseases of the Developing World, GlaxoSmithKline, Tres Cantos, Madrid, Spain
| | - Francisco Javier Gamo
- Tres Cantos Medicines Development Campus-Diseases of the Developing World, GlaxoSmithKline, Tres Cantos, Madrid, Spain
| | | | - Walter S Woltosz
- Simulations Plus, Inc., 42505 10th Street West, Lancaster, CA, 93534-7059, USA
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18
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Nyamai DW, Tastan Bishop Ö. Identification of Selective Novel Hits against Plasmodium falciparum Prolyl tRNA Synthetase Active Site and a Predicted Allosteric Site Using in silico Approaches. Int J Mol Sci 2020; 21:E3803. [PMID: 32471245 PMCID: PMC7312540 DOI: 10.3390/ijms21113803] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 05/10/2020] [Accepted: 05/19/2020] [Indexed: 12/14/2022] Open
Abstract
Recently, there has been increased interest in aminoacyl tRNA synthetases (aaRSs) as potential malarial drug targets. These enzymes play a key role in protein translation by the addition of amino acids to their cognate tRNA. The aaRSs are present in all Plasmodium life cycle stages, and thus present an attractive malarial drug target. Prolyl tRNA synthetase is a class II aaRS that functions in charging tRNA with proline. Various inhibitors against Plasmodium falciparum ProRS (PfProRS) active site have been designed. However, none have gone through clinical trials as they have been found to be highly toxic to human cells. Recently, a possible allosteric site was reported in PfProRS with two possible allosteric modulators: glyburide and TCMDC-124506. In this study, we sought to identify novel selective inhibitors targeting PfProRS active site and possible novel allosteric modulators of this enzyme. To achieve this, virtual screening of South African natural compounds against PfProRS and the human homologue was carried out using AutoDock Vina. The modulation of protein motions by ligand binding was studied by molecular dynamics (MD) using the GROningen MAchine for Chemical Simulations (GROMACS) tool. To further analyse the protein global motions and energetic changes upon ligand binding, principal component analysis (PCA), and free energy landscape (FEL) calculations were performed. Further, to understand the effect of ligand binding on the protein communication, dynamic residue network (DRN) analysis of the MD trajectories was carried out using the MD-TASK tool. A total of ten potential natural hit compounds were identified with strong binding energy scores. Binding of ligands to the protein caused observable global and residue level changes. Dynamic residue network calculations showed increase in betweenness centrality (BC) metric of residues at the allosteric site implying these residues are important in protein communication. A loop region at the catalytic domain between residues 300 and 350 and the anticodon binding domain showed significant contributions to both PC1 and PC2. Large motions were observed at a loop in the Z-domain between residues 697 and 710 which was also in agreement with RMSF calculations that showed increase in flexibility of residues in this region. Residues in this loop region are implicated in ATP binding and thus a change in dynamics may affect ATP binding affinity. Free energy landscape (FEL) calculations showed that the holo protein (protein-ADN complex) and PfProRS-SANC184 complexes were stable, as shown by the low energy with very few intermediates and hardly distinguishable low energy barriers. In addition, FEL results agreed with backbone RMSD distribution plots where stable complexes showed a normal RMSD distribution while unstable complexes had multimodal RMSD distribution. The betweenness centrality metric showed a loss of functional importance of key ATP binding site residues upon allosteric ligand binding. The deep basins in average L observed at the allosteric region imply that there is high accessibility of residues at this region. To further analyse BC and average L metrics data, we calculated the ΔBC and ΔL values by taking each value in the holo protein BC or L matrix less the corresponding value in the ligand-bound complex BC or L matrix. Interestingly, in allosteric complexes, residues located in a loop region implicated in ATP binding had negative ΔL values while in orthosteric complexes these residues had positive ΔL values. An increase in contact frequency between residues Ser263, Thr267, Tyr285, and Leu707 at the allosteric site and residues Thr397, Pro398, Thr402, and Gln395 at the ATP binding TXE loop was observed. In summary, this study identified five potential orthosteric inhibitors and five allosteric modulators against PfProRS. Allosteric modulators changed ATP binding site dynamics, as shown by RMSF, PCA, and DRN calculations. Changes in dynamics of the ATP binding site and increased contact frequency between residues at the proposed allosteric site and the ATP binding site may explain how allosteric modulators distort the ATP binding site and thus might inhibit PfProRS. The scaffolds of the identified hits in the study can be used as a starting point for antimalarial inhibitor development with low human cytotoxicity.
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Affiliation(s)
| | - Özlem Tastan Bishop
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Grahamstown 6140, South Africa;
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19
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Torrie LS, Robinson DA, Thomas MG, Hobrath JV, Shepherd SM, Post JM, Ko EJ, Ferreira RA, Mackenzie CJ, Wrobel K, Edwards DP, Gilbert IH, Gray DW, Fairlamb AH, De Rycker M. Discovery of an Allosteric Binding Site in Kinetoplastid Methionyl-tRNA Synthetase. ACS Infect Dis 2020; 6:1044-1057. [PMID: 32275825 PMCID: PMC7294809 DOI: 10.1021/acsinfecdis.9b00453] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
![]()
Methionyl-tRNA
synthetase (MetRS) is a chemically validated drug target in kinetoplastid
parasites Trypanosoma brucei and Leishmania
donovani. To date, all kinetoplastid MetRS inhibitors described
bind in a similar way to an expanded methionine pocket and an adjacent,
auxiliary pocket. In the current study, we have identified a structurally
novel class of inhibitors containing a 4,6-diamino-substituted pyrazolopyrimidine
core (the MetRS02 series). Crystallographic studies revealed that
MetRS02 compounds bind to an allosteric pocket in L. major MetRS not previously described, and enzymatic studies demonstrated
a noncompetitive mode of inhibition. Homology modeling of the Trypanosoma cruzi MetRS enzyme revealed key differences
in the allosteric pocket between the T. cruzi and Leishmania enzymes. These provide a likely explanation for
the lower MetRS02 potencies that we observed for the T. cruzi enzyme compared to the Leishmania enzyme. The identification
of a new series of MetRS inhibitors and the discovery of a new binding
site in kinetoplastid MetRS enzymes provide a novel strategy in the
search for new therapeutics for kinetoplastid diseases.
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Affiliation(s)
- Leah S. Torrie
- Drug Discovery Unit, Wellcome Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - David A. Robinson
- Drug Discovery Unit, Wellcome Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - Michael G. Thomas
- Drug Discovery Unit, Wellcome Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - Judith V. Hobrath
- Drug Discovery Unit, Wellcome Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - Sharon M. Shepherd
- Drug Discovery Unit, Wellcome Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - John M. Post
- Drug Discovery Unit, Wellcome Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - Eun-Jung Ko
- Drug Discovery Unit, Wellcome Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - Rafael Alves Ferreira
- Drug Discovery Unit, Wellcome Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - Claire J. Mackenzie
- Drug Discovery Unit, Wellcome Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - Karolina Wrobel
- Drug Discovery Unit, Wellcome Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - Darren P. Edwards
- Drug Discovery Unit, Wellcome Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - Ian H. Gilbert
- Drug Discovery Unit, Wellcome Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - David W. Gray
- Drug Discovery Unit, Wellcome Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - Alan H. Fairlamb
- Drug Discovery Unit, Wellcome Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - Manu De Rycker
- Drug Discovery Unit, Wellcome Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
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20
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Hou N, Jiang N, Ma Y, Zou Y, Piao X, Liu S, Chen Q. Low-Complexity Repetitive Epitopes of Plasmodium falciparum Are Decoys for Humoural Immune Responses. Front Immunol 2020; 11:610. [PMID: 32351503 PMCID: PMC7174639 DOI: 10.3389/fimmu.2020.00610] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 03/17/2020] [Indexed: 01/18/2023] Open
Abstract
Induction of humoural immunity is critical for clinical protection against malaria. More than 100 malaria vaccine candidates have been investigated at different developmental stages, but with limited protection. One of the roadblocks constrains the development of malaria vaccines is the poor immunogenicity of the antigens. The objective of this study was to map the linear B-cell epitopes of the Plasmodium falciparum erythrocyte invasion-associated antigens with a purpose of understanding humoural responses and protection. We conducted a large-scale screen using overlapping peptide microarrays of 37 proteins from the P. falciparum parasite, most of which are invasion-associated antigens which have been tested in clinical settings as vaccine candidates, with sera from individuals with various infection episodes. Analysis of the epitome of the antigens revealed that the most immunogenic epitopes were predominantly located in the low-complexity regions of the proteins containing repetitive and/or glutamate-rich motifs in different sequence contexts. However, in vitro assay showed the antibodies specific for these epitopes did not show invasion inhibitory effect. These discoveries indicated that the low-complexity regions of the parasite proteins might drive immune responses away from functional domains, which may be an instructive finding for the rational design of vaccine candidates.
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Affiliation(s)
- Nan Hou
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Ning Jiang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China.,The Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, Shenyang, China
| | - Yu Ma
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Yang Zou
- Beijing Key Laboratory for Research on Prevention and Treatment of Tropical Diseases, Beijing Tropical Medicine Research Institute, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Xianyu Piao
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Shuai Liu
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Qijun Chen
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.,Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China.,The Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, Shenyang, China
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21
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Novel chloroquine loaded curcumin based anionic linear globular dendrimer G2: a metabolomics study on Plasmodium falciparum in vitro using 1H NMR spectroscopy. Parasitology 2020; 147:747-759. [PMID: 32102701 DOI: 10.1017/s0031182020000372] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Due to side-effects and inefficiency of the drugs used in malaria treatment, finding alternative medicine with less side-effects has attracted much attention. In this regard, in the present study, nanocomposite synthesized and its effects on the metabolites of P. falciparum were investigated. Subsequent to synthesis of nanocomposites, characterization was carried out using nuclear magnetic resonance (NMR), liquid chromatography-mass spectrometry (LC-MS), scanning electron microscopy, dynamic light scattering and Fourier-transform infrared tests. Solubility and drug release were measured and its toxicity on Vero cell was assessed using the MTT assay. The antiparasitic effect of the nanocomposite on the metabolites of P. falciparum was investigated by 1H NMR spectroscopy. Among synthesized nanocomposites, the average size of 239 nm showed suitable solubility in water as well as slow drug release. The MTT assay showed no toxicity for Vero cell lines. Concentrations of 2.5 μg mL-1 of nanocomposite eliminated 82.6% of the total parasites. The most effected metabolic cycles were glyoxylate and dicarboxylate metabolism. In this study, 1H NMR spectroscopy was used with untargeted metabolomics to study the effect of the nanocomposite on P. falciparum. Playing an essential role in understanding drug-target interactions and characterization of mechanism of action or resistance exhibited by novel antiprotozoal drugs, can be achieved by targeting metabolic using LC-MS.
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Kovalenko OP, Volynets GP, Rybak MY, Starosyla SA, Gudzera OI, Lukashov SS, Bdzhola VG, Yarmoluk SM, Boshoff HI, Tukalo MA. Dual-target inhibitors of mycobacterial aminoacyl-tRNA synthetases among N-benzylidene- N'-thiazol-2-yl-hydrazines. MEDCHEMCOMM 2019; 10:2161-2169. [PMID: 32206244 PMCID: PMC7069510 DOI: 10.1039/c9md00347a] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 11/09/2019] [Indexed: 12/19/2022]
Abstract
Effective treatment of tuberculosis is challenged by the rapid development of Mycobacterium tuberculosis (Mtb) multidrug resistance that presumably could be overcome with novel multi-target drugs. Aminoacyl-tRNA synthetases (AARSs) are an essential part of protein biosynthesis machinery and attractive targets for drug discovery. Here, we experimentally verify a hypothesis of simultaneous targeting of structurally related AARSs by a single inhibitor. We previously identified a new class of mycobacterial leucyl-tRNA synthetase inhibitors, N-benzylidene-N'-thiazol-2-yl-hydrazines. Molecular docking of a library of novel N-benzylidene-N'-thiazol-2-yl-hydrazine derivatives into active sites of M. tuberculosis LeuRS (MtbLeuRS) and MetRS (MtbMetRS) resulted in a panel of the best ranking compounds, which were then evaluated for enzymatic potency. Screening data revealed 11 compounds active against MtbLeuRS and 28 compounds active against MtbMetRS. The hit compounds display dual inhibitory potency as demonstrated by IC50 values for both enzymes. Compound 3 is active against Mtb H37Rv cells in in vitro bioassays.
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Affiliation(s)
- Oksana P Kovalenko
- Department of Protein Synthesis Enzymology , Institute of Molecular Biology and Genetics , The NAS of Ukraine , 150 Zabolotnogo St , 03143 Kyiv , Ukraine . ; ; ; Tel: +38 044 5265589
| | - Galyna P Volynets
- Department of Medicinal Chemistry , Institute of Molecular Biology and Genetics , The NAS of Ukraine , 150 Zabolotnogo St , 03143 Kyiv , Ukraine
| | - Mariia Yu Rybak
- Department of Protein Synthesis Enzymology , Institute of Molecular Biology and Genetics , The NAS of Ukraine , 150 Zabolotnogo St , 03143 Kyiv , Ukraine . ; ; ; Tel: +38 044 5265589
| | - Sergiy A Starosyla
- Department of Medicinal Chemistry , Institute of Molecular Biology and Genetics , The NAS of Ukraine , 150 Zabolotnogo St , 03143 Kyiv , Ukraine
| | - Olga I Gudzera
- Department of Protein Synthesis Enzymology , Institute of Molecular Biology and Genetics , The NAS of Ukraine , 150 Zabolotnogo St , 03143 Kyiv , Ukraine . ; ; ; Tel: +38 044 5265589
| | - Sergiy S Lukashov
- Department of Medicinal Chemistry , Institute of Molecular Biology and Genetics , The NAS of Ukraine , 150 Zabolotnogo St , 03143 Kyiv , Ukraine
| | - Volodymyr G Bdzhola
- Department of Medicinal Chemistry , Institute of Molecular Biology and Genetics , The NAS of Ukraine , 150 Zabolotnogo St , 03143 Kyiv , Ukraine
| | - Sergiy M Yarmoluk
- Department of Medicinal Chemistry , Institute of Molecular Biology and Genetics , The NAS of Ukraine , 150 Zabolotnogo St , 03143 Kyiv , Ukraine
| | - Helena I Boshoff
- Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology , National Institute of Allergy and Infectious Disease , National Institute of Health , 5601 Fishers Lane, MSC 9806 , Bethesda , MD 20892-9806 , Maryland , USA
| | - Michael A Tukalo
- Department of Protein Synthesis Enzymology , Institute of Molecular Biology and Genetics , The NAS of Ukraine , 150 Zabolotnogo St , 03143 Kyiv , Ukraine . ; ; ; Tel: +38 044 5265589
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23
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Dual-targeted hit identification using pharmacophore screening. J Comput Aided Mol Des 2019; 33:955-964. [PMID: 31691918 DOI: 10.1007/s10822-019-00245-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 10/30/2019] [Indexed: 12/20/2022]
Abstract
Mycobacterium tuberculosis infection remains a major cause of global morbidity and mortality due to the increase of antibiotics resistance. Dual/multi-target drug discovery is a promising approach to overcome bacterial resistance. In this study, we built ligand-based pharmacophore models and performed pharmacophore screening in order to identify hit compounds targeting simultaneously two enzymes-M. tuberculosis leucyl-tRNA synthetase (LeuRS) and methionyl-tRNA synthetase (MetRS). In vitro aminoacylation assay revealed five compounds from different chemical classes inhibiting both enzymes. Among them the most active compound-3-(3-chloro-4-methoxy-phenyl)-5-[3-(4-fluoro-phenyl)-[1,2,4]oxadiazol-5-yl]-3H-[1,2,3]triazol-4-ylamine (1) inhibits mycobacterial LeuRS and MetRS with IC50 values of 13 µM and 13.8 µM, respectively. Molecular modeling study indicated that compound 1 has similar binding mode with the active sites of both aminoacyl-tRNA synthetases and can be valuable compound for further chemical optimization in order to find promising antituberculosis agents.
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Mishra S, Malhotra N, Kumari S, Sato M, Kikuchi H, Yogavel M, Sharma A. Conformational heterogeneity in apo and drug-bound structures of Toxoplasma gondii prolyl-tRNA synthetase. Acta Crystallogr F Struct Biol Commun 2019; 75:714-724. [PMID: 31702585 PMCID: PMC6839821 DOI: 10.1107/s2053230x19014808] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 11/01/2019] [Indexed: 11/11/2022] Open
Abstract
Prolyl-tRNA synthetase (PRS) is a member of the aminoacyl-tRNA synthetase family that drives protein translation in cells. The apicomplexan PRSs are validated targets of febrifugine (FF) and its halogenated derivative halofuginone (HF). PRSs are of great interest for drug development against Plasmodium falciparum and Toxoplasma gondii. In this study, structures of apo and FF-bound T. gondii (TgPRS) are revealed and the dynamic nature of the conformational changes that occur upon FF binding is unraveled. In addition, this study highlights significant conformational plasticity within two different crystal structures of apo PRSs but not within drug-bound PRSs. The apo PRSs exist in multi-conformational states and manifest pseudo-dimeric structures. In contrast, when FF is bound the PRS dimer adopts a highly symmetrical architecture. It is shown that TgPRS does not display extant fold switching, in contrast to P. falciparum PRS, despite having over 65% sequence identity. Finally, structure-comparison analyses suggest the utility of r.m.s.d. per residue (r.m.s.d./res) as a robust tool to detect structural alterations even when the r.m.s.d. is low. Apo TgPRS reveals FF/HF-induced rigidity and this work has implications for drug-design studies that rely on the apo structures of target proteins.
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Affiliation(s)
- Siddhartha Mishra
- Structural Parasitology, International Centre for Genetic Engineering and Biotechnology, New Delhi, Aruna Asaf Ali Marg, New Delhi, Delhi 110067, India
| | - Nipun Malhotra
- Structural Parasitology, International Centre for Genetic Engineering and Biotechnology, New Delhi, Aruna Asaf Ali Marg, New Delhi, Delhi 110067, India
| | - Shreya Kumari
- Structural Parasitology, International Centre for Genetic Engineering and Biotechnology, New Delhi, Aruna Asaf Ali Marg, New Delhi, Delhi 110067, India
| | - Mizuki Sato
- Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aza-Aoba, Aramaki, Aoba-ku, Sendai 980-8578, Japan
| | - Haruhisa Kikuchi
- Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aza-Aoba, Aramaki, Aoba-ku, Sendai 980-8578, Japan
| | - Manickam Yogavel
- Structural Parasitology, International Centre for Genetic Engineering and Biotechnology, New Delhi, Aruna Asaf Ali Marg, New Delhi, Delhi 110067, India
| | - Amit Sharma
- Structural Parasitology, International Centre for Genetic Engineering and Biotechnology, New Delhi, Aruna Asaf Ali Marg, New Delhi, Delhi 110067, India
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Chhibber-Goel J, Joshi S, Sharma A. Aminoacyl tRNA synthetases as potential drug targets of the Panthera pathogen Babesia. Parasit Vectors 2019; 12:482. [PMID: 31610802 PMCID: PMC6792207 DOI: 10.1186/s13071-019-3717-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Accepted: 09/14/2019] [Indexed: 11/18/2022] Open
Abstract
Background A century ago, pantheras were abundant across Asia. Illegal hunting and trading along with loss of habitat have resulted in the designation of Panthera as a genus of endangered species. In addition to the onslaught from humans, pantheras are also susceptible to outbreaks of several infectious diseases, including babesiosis. The latter is a hemoprotozoan disease whose causative agents are the eukaryotic parasites of the apicomplexan genus Babesia. Babesiosis affects a varied range of animals including humans (Homo sapiens), bovines (e.g. Bos taurus), pantheras (e.g. Panthera tigris, P. leo, P. pardus) and equines. Babesia spp. are transmitted by the tick vector Ixodes scapularis or ticks of domestic animals, namely Rhipicephalus (Boophilus) microplus and R. (B.) decoloratus. At the level of protein translation within these organisms, the conserved aminoacyl tRNA synthetase (aaRS) family offers an opportunity to identify the sequence and structural differences in the host (Panthera) and parasites (Babesia spp.) in order to exploit these for drug targeting Babesia spp. Methods Using computational tools we investigated the genomes of Babesia spp. and Panthera tigris so as to annotate their aaRSs. The sequences were analysed and their subcellular localizations were predicted using Target P1.1, SignalP 3.0, TMHMM v.2.0 and Deeploc 1.0 web servers. Structure-based analysis of the aaRSs from P. tigris and its protozoan pathogens Babesia spp. was performed using Phyre2 and chimera. Results We identified 33 (B. bovis), 34 (B. microti), 33 (B. bigemina) and 33 (P. tigris) aaRSs in these respective organisms. Poor sequence identity (~ 20–50%) between aaRSs from Babesia spp. and P. tigris was observed and this merits future experiments to validate new drug targets against Babesia spp. Conclusions Overall this work provides a foundation for experimental investigation of druggable aaRSs from Babesia sp. in an effort to control Babesiosis in Panthera.
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Affiliation(s)
- Jyoti Chhibber-Goel
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Sarthak Joshi
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Amit Sharma
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India.
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Chhibber‐Goel J, Sharma A. Side chain rotameric changes and backbone dynamics enable specific cladosporin binding in
Plasmodium falciparum
lysyl‐tRNA synthetase. Proteins 2019; 87:730-737. [DOI: 10.1002/prot.25699] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 04/03/2019] [Accepted: 04/22/2019] [Indexed: 01/26/2023]
Affiliation(s)
- Jyoti Chhibber‐Goel
- Structural Parasitology, Molecular Medicine GroupInternational Center for Genetic Engineering and Biotechnology New Delhi India
| | - Amit Sharma
- Structural Parasitology, Molecular Medicine GroupInternational Center for Genetic Engineering and Biotechnology New Delhi India
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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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28
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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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Sheridan CM, Garcia VE, Ahyong V, DeRisi JL. The Plasmodium falciparum cytoplasmic translation apparatus: a promising therapeutic target not yet exploited by clinically approved anti-malarials. Malar J 2018; 17:465. [PMID: 30541569 PMCID: PMC6292128 DOI: 10.1186/s12936-018-2616-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 12/06/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The continued spectre of resistance to existing anti-malarials necessitates the pursuit of novel targets and mechanisms of action for drug development. One class of promising targets consists of the 80S ribosome and its associated components comprising the parasite translational apparatus. Development of translation-targeting therapeutics requires a greater understanding of protein synthesis and its regulation in the malaria parasite. Research in this area has been limited by the lack of appropriate experimental methods, particularly a direct measure of parasite translation. METHODS An in vitro method directly measuring translation in whole-cell extracts from the malaria parasite Plasmodium falciparum, the PfIVT assay, and a historically-utilized indirect measure of translation, S35-radiolabel incorporation, were compared utilizing a large panel of known translation inhibitors as well as anti-malarial drugs. RESULTS Here, an extensive pharmacologic assessment of the PfIVT assay is presented, using a wide range of known inhibitors demonstrating its utility for studying activity of both ribosomal and non-ribosomal elements directly involved in translation. Further, the superiority of this assay over a historically utilized indirect measure of translation, S35-radiolabel incorporation, is demonstrated. Additionally, the PfIVT assay is utilized to investigate a panel of clinically approved anti-malarial drugs, many with unknown or unclear mechanisms of action, and show that none inhibit translation, reaffirming Plasmodium translation to be a viable alternative drug target. Within this set, mefloquine is unambiguously found to lack translation inhibition activity, despite having been recently mischaracterized as a ribosomal inhibitor. CONCLUSIONS This work exploits a direct and reproducible assay for measuring P. falciparum translation, demonstrating its value in the continued study of protein synthesis in malaria and its inhibition as a drug target.
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Affiliation(s)
- Christine Moore Sheridan
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA
| | - Valentina E Garcia
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA
| | - Vida Ahyong
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA
| | - Joseph L DeRisi
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA. .,Chan Zuckerberg Biohub, San Francisco, CA, USA.
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30
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Kumar S, Bhardwaj TR, Prasad DN, Singh RK. Drug targets for resistant malaria: Historic to future perspectives. Biomed Pharmacother 2018; 104:8-27. [PMID: 29758416 DOI: 10.1016/j.biopha.2018.05.009] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 04/22/2018] [Accepted: 05/07/2018] [Indexed: 01/05/2023] Open
Abstract
New antimalarial targets are the prime need for the discovery of potent drug candidates. In order to fulfill this objective, antimalarial drug researches are focusing on promising targets in order to develop new drug candidates. Basic metabolism and biochemical process in the malaria parasite, i.e. Plasmodium falciparum can play an indispensable role in the identification of these targets. But, the emergence of resistance to antimalarial drugs is an escalating comprehensive problem with the progress of antimalarial drug development. The development of resistance has highlighted the need for the search of novel antimalarial molecules. The pharmaceutical industries are committed to new drug development due to the global recognition of this life threatening resistance to the currently available antimalarial therapy. The recent developments in the understanding of parasite biology are exhilarating this resistance issue which is further being ignited by malaria genome project. With this background of information, this review was aimed to highlights and provides useful information on various present and promising treatment approaches for resistant malaria, new progresses, pursued by some innovative targets that have been explored till date. This review also discusses modern and futuristic multiple approaches to antimalarial drug discovery and development with pictorial presentations highlighting the various targets, that could be exploited for generating promising new drugs in the future for drug resistant malaria.
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Affiliation(s)
- Sahil Kumar
- School of Pharmacy and Emerging Sciences, Baddi University of Emerging Sciences & Technology, Baddi, Dist. Solan, 173205, Himachal Pradesh, India
| | - T R Bhardwaj
- School of Pharmacy and Emerging Sciences, Baddi University of Emerging Sciences & Technology, Baddi, Dist. Solan, 173205, Himachal Pradesh, India
| | - D N Prasad
- Department of Pharmaceutical Chemistry, Shivalik College of Pharmacy, Nangal, Dist. Rupnagar, 140126, Punjab, India
| | - Rajesh K Singh
- Department of Pharmaceutical Chemistry, Shivalik College of Pharmacy, Nangal, Dist. Rupnagar, 140126, Punjab, India.
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Schlott AC, Holder AA, Tate EW. N-Myristoylation as a Drug Target in Malaria: Exploring the Role of N-Myristoyltransferase Substrates in the Inhibitor Mode of Action. ACS Infect Dis 2018; 4:449-457. [PMID: 29363940 DOI: 10.1021/acsinfecdis.7b00203] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Malaria continues to be a significant cause of death and morbidity worldwide, and there is a need for new antimalarial drugs with novel targets. We have focused as a potential target for drug development on N-myristoyl transferase (NMT), an enzyme that acylates a wide range of substrate proteins. The NMT substrates in Plasmodium falciparum include some proteins that are common to processes in eukaryotes such as secretory transport and others that are unique to apicomplexan parasites. Myristoylation facilitates a protein interaction with membranes that may be strengthened by further lipidation, and the inhibition of NMT results in incorrect protein localization and the consequent disruption of function. The diverse roles of NMT substrates mean that NMT inhibition has a pleiotropic and severe impact on parasite development, growth, and multiplication. To study the mode of action underlying NMT inhibition, it is important to consider the function of proteins upstream and downstream of NMT. In this work, we therefore present our current perspective on the different functions of known NMT substrates as well as compare the inhibition of cotranslational myristoylation to the inhibition of known targets upstream of NMT.
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Affiliation(s)
- Anja C. Schlott
- Malaria Parasitology, The Francis Crick Institute, 1 Midland Road, NW1 1AT London, United Kingdom
- Department of Chemistry, Imperial College London, Imperial College Road, SW7 2AZ London, United Kingdom
| | - Anthony A. Holder
- Malaria Parasitology, The Francis Crick Institute, 1 Midland Road, NW1 1AT London, United Kingdom
| | - Edward W. Tate
- Department of Chemistry, Imperial College London, Imperial College Road, SW7 2AZ London, United Kingdom
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32
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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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33
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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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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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Habib S, Vaishya S, Gupta K. Translation in Organelles of Apicomplexan Parasites. Trends Parasitol 2016; 32:939-952. [DOI: 10.1016/j.pt.2016.07.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 07/19/2016] [Accepted: 07/25/2016] [Indexed: 01/27/2023]
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Diversity-oriented synthesis yields novel multistage antimalarial inhibitors. Nature 2016; 538:344-349. [PMID: 27602946 DOI: 10.1038/nature19804] [Citation(s) in RCA: 201] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 08/31/2016] [Indexed: 02/08/2023]
Abstract
Antimalarial drugs have thus far been chiefly derived from two sources-natural products and synthetic drug-like compounds. Here we investigate whether antimalarial agents with novel mechanisms of action could be discovered using a diverse collection of synthetic compounds that have three-dimensional features reminiscent of natural products and are underrepresented in typical screening collections. We report the identification of such compounds with both previously reported and undescribed mechanisms of action, including a series of bicyclic azetidines that inhibit a new antimalarial target, phenylalanyl-tRNA synthetase. These molecules are curative in mice at a single, low dose and show activity against all parasite life stages in multiple in vivo efficacy models. Our findings identify bicyclic azetidines with the potential to both cure and prevent transmission of the disease as well as protect at-risk populations with a single oral dose, highlighting the strength of diversity-oriented synthesis in revealing promising therapeutic targets.
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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: 15] [Impact Index Per Article: 1.9] [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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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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Discovery of potent anti-tuberculosis agents targeting leucyl-tRNA synthetase. Bioorg Med Chem 2016; 24:1023-31. [DOI: 10.1016/j.bmc.2016.01.028] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 12/23/2015] [Accepted: 01/15/2016] [Indexed: 01/05/2023]
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Bharathkumar H, Mohan CD, Rangappa S, Kang T, Keerthy HK, Fuchs JE, Kwon NH, Bender A, Kim S, Basappa, Rangappa KS. Screening of quinoline, 1,3-benzoxazine, and 1,3-oxazine-based small molecules against isolated methionyl-tRNA synthetase and A549 and HCT116 cancer cells including an in silico binding mode analysis. Org Biomol Chem 2015; 13:9381-7. [PMID: 26159576 DOI: 10.1039/c5ob00791g] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Elevated activity of methionyl-tRNA synthetase (MRS) in many cancers renders it a possible drug target in this disease area, as well as in a series of parasitic diseases. In the present work, we report the synthesis and in vitro screening of a library of 1,3-oxazines, benzoxazines and quinoline scaffolds against human MRS. Among the compounds tested, 2-(2-butyl-4-chloro-1-(4-phenoxybenzyl)-1H-imidazol-5-yl)-5-(4-methoxyphenyl)-1-oxa-3-azaspiro[5.5]undecane (compound 21) and 2-(2-butyl-4-chloro-1-(4-nitrobenzyl)-1H-imidazol-5-yl)-2,4-dihydro-1H-benzo[d][1,3]oxazine (compound 8) were found to be potent inhibitors of MRS. Additionally, these compounds significantly suppressed the proliferation of A549 and HCT116 cells with IC50 values of 28.4, 17.7, 41.9, and 19.8 μM respectively. Molecular docking studies suggested that the ligand binding orientation overlaps with the original positions of both methionine and adenosine of MRS. This suggests the binding of compound 21 against MRS, which might lead the inhibitory activity towards cancer cells.
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