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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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Mishra S, Malhotra N, Laleu B, Chakraborti S, Yogavel M, Sharma A. ATP mimetics targeting prolyl-tRNA synthetases as a new avenue for antimalarial drug development. iScience 2024; 27:110049. [PMID: 39104570 PMCID: PMC11298890 DOI: 10.1016/j.isci.2024.110049] [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: 02/15/2023] [Revised: 09/24/2023] [Accepted: 05/17/2024] [Indexed: 08/07/2024] Open
Abstract
The prolyl-tRNA synthetase (PRS) is an essential enzyme for protein translation and a validated target against malaria parasite. We describe five ATP mimetics (L95, L96, L97, L35, and L36) against PRS, exhibiting enhanced thermal stabilities in co-operativity with L-proline. L35 displays the highest thermal stability akin to halofuginone, an established inhibitor of Plasmodium falciparum PRS. Four compounds exhibit nanomolar inhibitory potency against PRS. L35 exhibits the highest potency of ∼1.6 nM against asexual-blood-stage (ABS) and ∼100-fold (effective concentration [EC50]) selectivity for the parasite. The macromolecular structures of PfPRS with L95 and L97 in complex with L-pro reveal their binding modes and catalytic site malleability. Arg401 of PfPRS oscillates between two rotameric configurations when in complex with L95, whereas it is locked in one of the configurations due to the larger size of L97. Harnessing such specific and selective chemical features holds significant promise for designing potential inhibitors and expediting drug development efforts.
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Affiliation(s)
- Siddhartha Mishra
- Molecular Medicine – Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi 110067, India
- ICMR-National Institute of Malaria Research (NIMR), Dwarka, New Delhi 110077, India
- Academy of Scientific and Innovative Research (AcSIR), UP, India
| | - Nipun Malhotra
- Molecular Medicine – Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Benoît Laleu
- Medicines for Malaria Venture (MMV), International Center Cointrin (ICC), Route de Pré-Bois 20, 1215 Geneva, Switzerland
| | - Soumyananda Chakraborti
- ICMR-National Institute of Malaria Research (NIMR), Dwarka, New Delhi 110077, India
- Academy of Scientific and Innovative Research (AcSIR), UP, India
| | - Manickam Yogavel
- Molecular Medicine – Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Amit Sharma
- Molecular Medicine – Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi 110067, India
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Qiao H, Wang Z, Yang H, Xia M, Yang G, Bai F, Wang J, Fang P. Specific glycine-dependent enzyme motion determines the potency of conformation selective inhibitors of threonyl-tRNA synthetase. Commun Biol 2024; 7:867. [PMID: 39014102 PMCID: PMC11252418 DOI: 10.1038/s42003-024-06559-x] [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: 02/26/2024] [Accepted: 07/05/2024] [Indexed: 07/18/2024] Open
Abstract
The function of proteins depends on their correct structure and proper dynamics. Understanding the dynamics of target proteins facilitates drug design and development. However, dynamic information is often hidden in the spatial structure of proteins. It is important but difficult to identify the specific residues that play a decisive role in protein dynamics. Here, we report that a critical glycine residue (Gly463) dominates the motion of threonyl-tRNA synthetase (ThrRS) and the sensitivity of the enzyme to antibiotics. Obafluorin (OB), a natural antibiotic, is a novel covalent inhibitor of ThrRS. The binding of OB induces a large conformational change in ThrRS. Through five crystal structures, biochemical and biophysical analyses, and computational simulations, we found that Gly463 plays an important role in the dynamics of ThrRS. Mutating this flexible residue into more rigid residues did not damage the enzyme's three-dimensional structure but significantly improved the thermal stability of the enzyme and suppressed its ability to change conformation. These mutations cause resistance of ThrRS to antibiotics that are conformationally selective, such as OB and borrelidin. This work not only elucidates the molecular mechanism of the self-resistance of OB-producing Pseudomonas fluorescens but also emphasizes the importance of backbone kinetics for aminoacyl-tRNA synthetase-targeting drug development.
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Affiliation(s)
- Hang Qiao
- State Key Laboratory of Chemical Biology, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, 200032, Shanghai, China
| | - Zilu Wang
- State Key Laboratory of Chemical Biology, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, 200032, Shanghai, China
| | - Hao Yang
- Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, 201210, Shanghai, China
| | - Mingyu Xia
- State Key Laboratory of Chemical Biology, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, 200032, Shanghai, China
| | - Guang Yang
- School of Chemistry and Materials Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, 1 Sub-lane Xiangshan, 310024, Hangzhou, China
| | - Fang Bai
- Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, 201210, Shanghai, China.
- School of Information Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, 201210, Shanghai, China.
- Shanghai Clinical Research and Trial Center, 201210, Shanghai, China.
| | - Jing Wang
- State Key Laboratory of Chemical Biology, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, 200032, Shanghai, China.
- School of Chemistry and Materials Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, 1 Sub-lane Xiangshan, 310024, Hangzhou, China.
| | - Pengfei Fang
- State Key Laboratory of Chemical Biology, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, 200032, Shanghai, China.
- School of Chemistry and Materials Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, 1 Sub-lane Xiangshan, 310024, Hangzhou, China.
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, 510006, Guangzhou, China.
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Ence CC, Uddin T, Borrel J, Mittal P, Xie H, Zoller J, Sharma A, Comer E, Schreiber SL, Melillo B, Sibley LD, Chatterjee AK. Bicyclic Pyrrolidine Inhibitors of Toxoplasma gondii Phenylalanine t-RNA Synthetase with Antiparasitic Potency In Vitro and Brain Exposure. ACS Infect Dis 2024; 10:2212-2221. [PMID: 38743643 PMCID: PMC11299587 DOI: 10.1021/acsinfecdis.4c00170] [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] [Indexed: 05/16/2024]
Abstract
Previous studies have shown that bicyclic azetidines are potent and selective inhibitors of apicomplexan phenylalanine tRNA synthetase (PheRS), leading to parasite growth inhibition in vitro and in vivo, including in models of Toxoplasma infection. Despite these useful properties, additional optimization is required for the development of efficacious treatments of toxoplasmosis from this inhibitor series, in particular, to achieve optimal exposure in the brain. Here, we describe a series of PheRS inhibitors built on a new bicyclic pyrrolidine core scaffold designed to retain the exit-vector geometry of the isomeric bicyclic azetidine core scaffold while offering avenues to sample diverse chemical space. Relative to the parent series, bicyclic pyrrolidines retain reasonable potency and target selectivity for parasite PheRS vs host. Further structure-activity relationship studies revealed that the introduction of aliphatic groups improved potency and ADME and PK properties, including brain exposure. The identification of this new scaffold provides potential opportunities to extend the analogue series to further improve selectivity and potency and ultimately deliver a novel, efficacious treatment of toxoplasmosis.
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Affiliation(s)
| | - Taher Uddin
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63130, USA
| | - Julien Borrel
- Chemical Biology and Therapeutics Science Program, Broad Institute, Cambridge, MA 02142, USA
| | - Payal Mittal
- Molecular Medicine-Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India
- ICMR-NIMR, Sector-8, Dwarka, New Delhi-110077, India, Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India
| | - Han Xie
- Calibr at Scripps Research, La Jolla, CA 92037, USA
| | - Jochen Zoller
- Chemical Biology and Therapeutics Science Program, Broad Institute, Cambridge, MA 02142, USA
| | - Amit Sharma
- Molecular Medicine-Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India
| | - Eamon Comer
- 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, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - L. David Sibley
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63130, USA
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5
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Ence CC, Uddin T, Borrel J, Mittal P, Xie H, Zoller J, Sharma A, Comer E, Schreiber SL, Melillo B, Sibley LD, Chatterjee AK. Bicyclic pyrrolidine inhibitors of Toxoplasma gondii phenylalanine t-RNA synthetase with antiparasitic potency in vitro and brain exposure. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.28.582607. [PMID: 38464220 PMCID: PMC10925249 DOI: 10.1101/2024.02.28.582607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Previous studies have shown that bicyclic azetidines are potent and selective inhibitors of apicomplexan phenylalanine tRNA synthetase (PheRS), leading to parasite growth inhibition in vitro and in vivo, including in models of Toxoplasma infection. Despite these useful properties, additional optimization is required for the development of efficacious treatments of toxoplasmosis from this inhibitor series, in particular to achieve sufficient exposure in the brain. Here, we describe a series of PheRS inhibitors built on a new bicyclic pyrrolidine core scaffold designed to retain the exit-vector geometry of the isomeric bicyclic azetidine core scaffold while offering avenues to sample diverse chemical space. Relative to the parent series, bicyclic pyrrolidines retain reasonable potency and target selectivity for parasite PheRS vs. host. Further structure-activity relationship studies revealed that the introduction of aliphatic groups improved potency, ADME and PK properties, including brain exposure. The identification of this new scaffold provides potential opportunities to extend the analog series to further improve selectivity and potency and ultimately deliver a novel, efficacious treatment of toxoplasmosis.
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Affiliation(s)
| | - Taher Uddin
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63130, USA
| | - Julien Borrel
- Chemical Biology and Therapeutics Science Program, Broad Institute, Cambridge, MA 02142, USA
| | - Payal Mittal
- Molecular Medicine-Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India
- ICMR-NIMR, Sector-8, Dwarka, New Delhi-110077, India, Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India
| | - Han Xie
- Calibr at Scripps Research, La Jolla, CA 92037, USA
| | - Jochen Zoller
- Chemical Biology and Therapeutics Science Program, Broad Institute, Cambridge, MA 02142, USA
| | - Amit Sharma
- Molecular Medicine-Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India
| | - Eamon Comer
- 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, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - L. David Sibley
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63130, USA
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Cheuka PM, Njaria P, Mayoka G, Funjika E. Emerging Drug Targets for Antimalarial Drug Discovery: Validation and Insights into Molecular Mechanisms of Function. J Med Chem 2024; 67:838-863. [PMID: 38198596 DOI: 10.1021/acs.jmedchem.3c01828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2024]
Abstract
Approximately 619,000 malaria deaths were reported in 2021, and resistance to recommended drugs, including artemisinin-combination therapies (ACTs), threatens malaria control. Treatment failure with ACTs has been found to be as high as 93% in northeastern Thailand, and parasite mutations responsible for artemisinin resistance have already been reported in some African countries. Therefore, there is an urgent need to identify alternative treatments with novel targets. In this Perspective, we discuss some promising antimalarial drug targets, including enzymes involved in proteolysis, DNA and RNA metabolism, protein synthesis, and isoprenoid metabolism. Other targets discussed are transporters, Plasmodium falciparum acetyl-coenzyme A synthetase, N-myristoyltransferase, and the cyclic guanosine monophosphate-dependent protein kinase G. We have outlined mechanistic details, where these are understood, underpinning the biological roles and hence druggability of such targets. We believe that having a clear understanding of the underlying chemical interactions is valuable to medicinal chemists in their quest to design appropriate inhibitors.
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Affiliation(s)
- Peter Mubanga Cheuka
- Department of Chemistry, School of Natural Sciences, University of Zambia, P.O. Box 32379, Lusaka 10101, Zambia
| | - Paul Njaria
- Department of Pharmacognosy and Pharmaceutical Chemistry, Kenyatta University, P.O. Box 14548-00400, Nairobi 00100, Kenya
| | - Godfrey Mayoka
- Department of Pharmacology and Pharmacognosy, School of Pharmacy, Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000-00200, Nairobi 00100, Kenya
| | - Evelyn Funjika
- Department of Chemistry, School of Natural Sciences, University of Zambia, P.O. Box 32379, Lusaka 10101, Zambia
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Siqueira-Neto JL, Wicht KJ, Chibale K, Burrows JN, Fidock DA, Winzeler EA. Antimalarial drug discovery: progress and approaches. Nat Rev Drug Discov 2023; 22:807-826. [PMID: 37652975 PMCID: PMC10543600 DOI: 10.1038/s41573-023-00772-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/17/2023] [Indexed: 09/02/2023]
Abstract
Recent antimalarial drug discovery has been a race to produce new medicines that overcome emerging drug resistance, whilst considering safety and improving dosing convenience. Discovery efforts have yielded a variety of new molecules, many with novel modes of action, and the most advanced are in late-stage clinical development. These discoveries have led to a deeper understanding of how antimalarial drugs act, the identification of a new generation of drug targets, and multiple structure-based chemistry initiatives. The limited pool of funding means it is vital to prioritize new drug candidates. They should exhibit high potency, a low propensity for resistance, a pharmacokinetic profile that favours infrequent dosing, low cost, preclinical results that demonstrate safety and tolerability in women and infants, and preferably the ability to block Plasmodium transmission to Anopheles mosquito vectors. In this Review, we describe the approaches that have been successful, progress in preclinical and clinical development, and existing challenges. We illustrate how antimalarial drug discovery can serve as a model for drug discovery in diseases of poverty.
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Affiliation(s)
| | - Kathryn J Wicht
- 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, Department of Chemistry and Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Rondebosch, South Africa
| | - Kelly Chibale
- 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, Department of Chemistry and Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Rondebosch, South Africa
| | | | - David A Fidock
- Department of Microbiology and Immunology and Center for Malaria Therapeutics and Antimicrobial Resistance, Division of Infectious Diseases, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA
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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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Kreutzfeld O, Tumwebaze PK, Okitwi M, Orena S, Byaruhanga O, Katairo T, Conrad MD, Rasmussen SA, Legac J, Aydemir O, Giesbrecht D, Forte B, Campbell P, Smith A, Kano H, Nsobya SL, Blasco B, Duffey M, Bailey JA, Cooper RA, Rosenthal PJ. Susceptibility of Ugandan Plasmodium falciparum Isolates to the Antimalarial Drug Pipeline. Microbiol Spectr 2023; 11:e0523622. [PMID: 37158739 PMCID: PMC10269555 DOI: 10.1128/spectrum.05236-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 04/10/2023] [Indexed: 05/10/2023] Open
Abstract
Malaria, especially Plasmodium falciparum infection, remains an enormous problem, and its treatment and control are seriously challenged by drug resistance. New antimalarial drugs are needed. To characterize the Medicines for Malaria Venture pipeline of antimalarials under development, we assessed the ex vivo drug susceptibilities to 19 compounds targeting or potentially impacted by mutations in P. falciparum ABC transporter I family member 1, acetyl-CoA synthetase, cytochrome b, dihydroorotate dehydrogenase, elongation factor 2, lysyl-tRNA synthetase, phenylalanyl-tRNA synthetase, plasmepsin X, prodrug activation and resistance esterase, and V-type H+ ATPase of 998 fresh P. falciparum clinical isolates collected in eastern Uganda from 2015 to 2022. Drug susceptibilities were assessed by 72-h growth inhibition (half-maximum inhibitory concentration [IC50]) assays using SYBR green. Field isolates were highly susceptible to lead antimalarials, with low- to midnanomolar median IC50s, near values previously reported for laboratory strains, for all tested compounds. However, outliers with decreased susceptibilities were identified. Positive correlations between IC50 results were seen for compounds with shared targets. We sequenced genes encoding presumed targets to characterize sequence diversity, search for polymorphisms previously selected with in vitro drug pressure, and determine genotype-phenotype associations. We identified many polymorphisms in target genes, generally in <10% of isolates, but none were those previously selected in vitro with drug pressure, and none were associated with significantly decreased ex vivo drug susceptibility. Overall, Ugandan P. falciparum isolates were highly susceptible to 19 compounds under development as next-generation antimalarials, consistent with a lack of preexisting or novel resistance-conferring mutations in circulating Ugandan parasites. IMPORTANCE Drug resistance necessitates the development of new antimalarial drugs. It is important to assess the activities of compounds under development against parasites now causing disease in Africa, where most malaria cases occur, and to determine if mutations in these parasites may limit the efficacies of new agents. We found that African isolates were generally highly susceptible to the 19 studied lead antimalarials. Sequencing of the presumed drug targets identified multiple mutations in these genes, but these mutations were generally not associated with decreased antimalarial activity. These results offer confidence that the activities of the tested antimalarial compounds now under development will not be limited by preexisting resistance-mediating mutations in African malaria parasites.
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Affiliation(s)
- Oriana Kreutzfeld
- University of California, San Francisco, San Francisco, California, USA
| | | | - Martin Okitwi
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Stephen Orena
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | | | - Thomas Katairo
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Melissa D. Conrad
- University of California, San Francisco, San Francisco, California, USA
| | | | - Jennifer Legac
- University of California, San Francisco, San Francisco, California, USA
| | - Ozkan Aydemir
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | | | - Barbara Forte
- Wellcome Centre for Anti-Infectives Research, Division of Biological Chemistry and Drug Discovery, University of Dundee, Dundee, United Kingdom
| | - Peter Campbell
- Wellcome Centre for Anti-Infectives Research, Division of Biological Chemistry and Drug Discovery, University of Dundee, Dundee, United Kingdom
| | - Alasdair Smith
- Wellcome Centre for Anti-Infectives Research, Division of Biological Chemistry and Drug Discovery, University of Dundee, Dundee, United Kingdom
| | - Hiroki Kano
- Mitsubishi Tanabe Pharma Corporation, Yokohama, Japan
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10
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Nasim F, Qureshi IA. Aminoacyl tRNA Synthetases: Implications of Structural Biology in Drug Development against Trypanosomatid Parasites. ACS OMEGA 2023; 8:14884-14899. [PMID: 37151504 PMCID: PMC10157851 DOI: 10.1021/acsomega.3c00826] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 03/29/2023] [Indexed: 05/09/2023]
Abstract
The ensemble of aminoacyl tRNA synthetases is regarded as a key component of the protein translation machinery. With the progressive increase in structure-based studies on tRNA synthetase-ligand complexes, the detailed picture of these enzymes is becoming clear. Having known their critical role in deciphering the genetic code in a living system, they have always been chosen as one of the important targets for development of antimicrobial drugs. Later on, the role of aminoacyl tRNA synthetases (aaRSs) on the survivability of trypanosomatids has also been validated. It became evident through several gene knockout studies that targeting even one of these enzymes affected parasitic growth drastically. Such successful studies have inspired researchers to search for inhibitors that could specifically target trypanosomal aaRSs, and their never-ending efforts have provided fruitful results. Taking all such studies into consideration, these macromolecules of prime importance deserve further investigation for the development of drugs that cure spectrum of infections caused by trypanosomatids. In this review, we have compiled advancements of over a decade that have taken place in the pursuit of devising drugs by using trypanosomatid aaRSs as a major target of interest. Several of these inhibitors work on an exemplary low concentration range without posing any threat to the mammalian cells which is a very critical aspect of the drug discovery process. Advancements have been made in terms of using structural biology as an important tool to analyze the architecture of the trypanosomatids aaRSs and concoction of inhibitors with augmented specificities toward their targets. Some of the inhibitors that have been tested on other parasites successfully but their efficacy has so far not been validated against these trypanosomatids have also been appended.
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11
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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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Yogavel M, Bougdour A, Mishra S, Malhotra N, Chhibber-Goel J, Bellini V, Harlos K, Laleu B, Hakimi MA, Sharma A. Targeting prolyl-tRNA synthetase via a series of ATP-mimetics to accelerate drug discovery against toxoplasmosis. PLoS Pathog 2023; 19:e1011124. [PMID: 36854028 PMCID: PMC9974123 DOI: 10.1371/journal.ppat.1011124] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 01/16/2023] [Indexed: 03/02/2023] Open
Abstract
The prolyl-tRNA synthetase (PRS) is a validated drug target for febrifugine and its synthetic analog halofuginone (HFG) against multiple apicomplexan parasites including Plasmodium falciparum and Toxoplasma gondii. Here, a novel ATP-mimetic centered on 1-(pyridin-4-yl) pyrrolidin-2-one (PPL) scaffold has been validated to bind to Toxoplasma gondii PRS and kill toxoplasma parasites. PPL series exhibited potent inhibition at the cellular (T. gondii parasites) and enzymatic (TgPRS) levels compared to the human counterparts. Cell-based chemical mutagenesis was employed to determine the mechanism of action via a forward genetic screen. Tg-resistant parasites were analyzed with wild-type strain by RNA-seq to identify mutations in the coding sequence conferring drug resistance by computational analysis of variants. DNA sequencing established two mutations, T477A and T592S, proximal to terminals of the PPL scaffold and not directly in the ATP, tRNA, or L-pro sites, as supported by the structural data from high-resolution crystal structures of drug-bound enzyme complexes. These data provide an avenue for structure-based activity enhancement of this chemical series as anti-infectives.
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Affiliation(s)
- Manickam Yogavel
- Molecular Medicine–Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi, India
| | - Alexandre Bougdour
- Institute for Advanced Biosciences (IAB), Team Host-Pathogen Interactions and Immunity to Infection, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
| | - Siddhartha Mishra
- Molecular Medicine–Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
- ICMR-National Institute of Malaria Research, Dwarka, New Delhi, India
| | - Nipun Malhotra
- Molecular Medicine–Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi, India
| | - Jyoti Chhibber-Goel
- Molecular Medicine–Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi, India
| | - Valeria Bellini
- Institute for Advanced Biosciences (IAB), Team Host-Pathogen Interactions and Immunity to Infection, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
| | - Karl Harlos
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Benoît Laleu
- Medicines for Malaria Venture (MMV), International Center Cointrin (ICC), Geneva, Switzerland
| | - Mohamed-Ali Hakimi
- Institute for Advanced Biosciences (IAB), Team Host-Pathogen Interactions and Immunity to Infection, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
| | - Amit Sharma
- Molecular Medicine–Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
- ICMR-National Institute of Malaria Research, Dwarka, New Delhi, India
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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: 13] [Impact Index Per Article: 6.5] [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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Guerra F, Winzeler EA. New targets for antimalarial drug discovery. Curr Opin Microbiol 2022; 70:102220. [PMID: 36228458 PMCID: PMC9934905 DOI: 10.1016/j.mib.2022.102220] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 08/22/2022] [Accepted: 09/10/2022] [Indexed: 01/25/2023]
Abstract
Phenotypic screening methods have placed numerous preclinical candidates into the antimalarial drug-discovery pipeline. As more chemically validated targets become available, efforts are shifting to target-based drug discovery. Here, we briefly review some of the most attractive targets that have been identified in recent years.
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Affiliation(s)
- Francisco Guerra
- Department of Pediatrics MC 0760, School of Medicine, University of California, La Jolla, San Diego, CA 92093, USA
| | - Elizabeth A Winzeler
- Department of Pediatrics MC 0760, School of Medicine, University of California, La Jolla, San Diego, CA 92093, USA.
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Gill J, Sharma A. Genomic analysis of single nucleotide polymorphisms in malaria parasite drug targets. Parasit Vectors 2022; 15:309. [PMID: 36042490 PMCID: PMC9425944 DOI: 10.1186/s13071-022-05422-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 07/22/2022] [Indexed: 12/02/2022] Open
Abstract
Malaria is a life-threatening parasitic disease caused by members of the genus Plasmodium. The development and spread of drug-resistant strains of Plasmodium parasites represent a major challenge to malaria control and elimination programmes. Evaluating genetic polymorphism in a drug target improves our understanding of drug resistance and facilitates drug design. Approximately 450 and 19 whole-genome assemblies of Plasmodium falciparum and Plasmodium vivax, respectively, are currently available, and numerous sequence variations have been found due to the presence of single nucleotide polymorphism (SNP). In the study reported here, we analysed global SNPs in the malaria parasite aminoacyl-tRNA synthetases (aaRSs). Our analysis revealed 3182 unique SNPs in the 20 cytoplasmic P. falciparum aaRSs. Structural mapping of SNPs onto the three-dimensional inhibitor-bound complexes of the three advanced drug targets within aaRSs revealed a remarkably low mutation frequency in the crucial aminoacylation domains, low overall occurrence of mutations across samples and high conservation in drug/substrate binding regions. In contrast to aaRSs, dihydropteroate synthase (DHPS), also a malaria drug target, showed high occurrences of drug resistance-causing mutations. Our results show that it is pivotal to screen potent malaria drug targets against global SNP profiles to assess genetic variances to ensure success in designing drugs against validated targets and tackle drug resistance early on.
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Affiliation(s)
- Jasmita Gill
- ICMR-National Institute of Malaria Research, Sector 8, Dwarka, 110077, New Delhi, India
| | - Amit Sharma
- ICMR-National Institute of Malaria Research, Sector 8, Dwarka, 110077, New Delhi, India. .,International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, 110067, India.
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Manickam Y, Malhotra N, Mishra S, Babbar P, Dusane A, Laleu B, Bellini V, Hakimi MA, Bougdour A, Sharma A. Double drugging of prolyl-tRNA synthetase provides a new paradigm for anti-infective drug development. PLoS Pathog 2022; 18:e1010363. [PMID: 35333915 PMCID: PMC9004777 DOI: 10.1371/journal.ppat.1010363] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 04/12/2022] [Accepted: 02/11/2022] [Indexed: 01/13/2023] Open
Abstract
Toxoplasmosis is caused by Toxoplasma gondii and in immunocompromised patients it may lead to seizures, encephalitis or death. The conserved enzyme prolyl-tRNA synthetase (PRS) is a validated druggable target in Toxoplasma gondii but the traditional ‘single target–single drug’ approach has its caveats. Here, we describe two potent inhibitors namely halofuginone (HFG) and a novel ATP mimetic (L95) that bind to Toxoplasma gondii PRS simultaneously at different neighbouring sites to cover all three of the enzyme substrate subsites. HFG and L95 act as one triple-site inhibitor in tandem and form an unusual ternary complex wherein HFG occupies the 3’-end of tRNA and the L-proline (L-pro) binding sites while L95 occupies the ATP pocket. These inhibitors exhibit nanomolar IC50 and EC50 values independently, and when given together reveal an additive mode of action in parasite inhibition assays. This work validates a novel approach and lays a structural framework for further drug development based on simultaneous targeting of multiple pockets to inhibit druggable proteins. Among infectious diseases, parasitic diseases are a major cause of death and morbidity. Toxoplasmosis is caused by an infection of the apicomplexan parasite Toxoplasma gondii. In immunocompromised patients Toxoplasmosis may lead to seizures, encephalitis or death. Novel therapeutics for human parasites are constantly needed. In recent years, the aminoacyl-tRNA synthetase (aaRS) enzyme family has been validated as a drug target for several parasitic infections. The Toxoplasma gondii prolyl-tRNA synthetase inhibitor halofuginone (HFG) has been validated earlier but here we show that an ATP-mimic called L95 is a potent inhibitor and can bind to the target enzyme in the presence of HFG. Thus, the two inhibitors described in this study simultaneously occupy all three natural substrate (ATP, L-amino acid and 3’-end of tRNA) binding pockets and thereby inhibit the enzyme leading to parasite death. This unprecedented double drugging of a pathogen enzyme may delay resistance mutation generation and this approach opens the path to multi-drugging of validated parasite proteins.
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Affiliation(s)
- Yogavel Manickam
- Molecular Medicine–Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Nipun Malhotra
- Molecular Medicine–Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Siddhartha Mishra
- Molecular Medicine–Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
- ICMR-National Institute of Malaria Research (NIMR), New Delhi, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Palak Babbar
- Molecular Medicine–Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Abhishek Dusane
- Molecular Medicine–Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Benoît Laleu
- Medicines for Malaria Venture (MMV), International Center Cointrin (ICC), Geneva, Switzerland
| | - Valeria Bellini
- Institute for Advanced Biosciences (IAB), Team Host-Pathogen Interactions and Immunity to Infection, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
| | - Mohamed-Ali Hakimi
- Institute for Advanced Biosciences (IAB), Team Host-Pathogen Interactions and Immunity to Infection, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
| | - Alexandre Bougdour
- Institute for Advanced Biosciences (IAB), Team Host-Pathogen Interactions and Immunity to Infection, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
- * E-mail: (AB); (AS)
| | - Amit Sharma
- Molecular Medicine–Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
- ICMR-National Institute of Malaria Research (NIMR), New Delhi, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
- * E-mail: (AB); (AS)
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Bicyclic azetidines target acute and chronic stages of Toxoplasma gondii by inhibiting parasite phenylalanyl t-RNA synthetase. Nat Commun 2022; 13:459. [PMID: 35075105 PMCID: PMC8786932 DOI: 10.1038/s41467-022-28108-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 01/10/2022] [Indexed: 11/24/2022] Open
Abstract
Toxoplasma gondii commonly infects humans and while most infections are controlled by the immune response, currently approved drugs are not capable of clearing chronic infection in humans. Hence, approximately one third of the world’s human population is at risk of reactivation, potentially leading to severe sequelae. To identify new candidates for treating chronic infection, we investigated a series of compounds derived from diversity-oriented synthesis. Bicyclic azetidines are potent low nanomolar inhibitors of phenylalanine tRNA synthetase (PheRS) in T. gondii, with excellent selectivity. Biochemical and genetic studies validate PheRS as the primary target of bicyclic azetidines in T. gondii, providing a structural basis for rational design of improved analogs. Favorable pharmacokinetic properties of a lead compound provide excellent protection from acute infection and partial protection from chronic infection in an immunocompromised mouse model of toxoplasmosis. Collectively, PheRS inhibitors of the bicyclic azetidine series offer promise for treatment of chronic toxoplasmosis. Current treatments for toxoplasmosis are limited by adverse reactions and inability to cure chronic infections dominated by semi-dormant cyst forms. Here the authors demonstrate the potential of small molecule inhibitors of PheRS for controlling acute and chronic toxoplasmosis.
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Chakraborti S, Chhibber-Goel J, Sharma A. Drug targeting of aminoacyl-tRNA synthetases in Anopheles species and Aedes aegypti that cause malaria and dengue. Parasit Vectors 2021; 14:605. [PMID: 34895309 PMCID: PMC8665550 DOI: 10.1186/s13071-021-05106-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Accepted: 11/19/2021] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Mosquito-borne diseases have a devastating impact on human civilization. A few species of Anopheles mosquitoes are responsible for malaria transmission, and while there has been a reduction in malaria-related deaths worldwide, growing insecticide resistance is a cause for concern. Aedes mosquitoes are known vectors of viral infections, including dengue, yellow fever, chikungunya, and Zika. Aminoacyl-tRNA synthetases (aaRSs) are key players in protein synthesis and are potent anti-infective drug targets. The structure-function activity relationship of aaRSs in mosquitoes (in particular, Anopheles and Aedes spp.) remains unexplored. METHODS We employed computational techniques to identify aaRSs from five different mosquito species (Anopheles culicifacies, Anopheles stephensi, Anopheles gambiae, Anopheles minimus, and Aedes aegypti). The VectorBase database ( https://vectorbase.org/vectorbase/app ) and web-based tools were utilized to predict the subcellular localizations (TargetP-2.0, UniProt, DeepLoc-1.0), physicochemical characteristics (ProtParam), and domain arrangements (PfAM, InterPro) of the aaRSs. Structural models for prolyl (PRS)-, and phenylalanyl (FRS)-tRNA synthetases-were generated using the I-TASSER and Phyre protein modeling servers. RESULTS Among the vector species, a total of 37 (An. gambiae), 37 (An. culicifacies), 37 (An. stephensi), 37 (An. minimus), and 35 (Ae. aegypti) different aaRSs were characterized within their respective mosquito genomes. Sequence identity amongst the aaRSs from the four Anopheles spp. was > 80% and in Ae. aegypti was > 50%. CONCLUSIONS Structural analysis of two important aminoacyl-tRNA synthetases [prolyl (PRS) and phenylanalyl (FRS)] of Anopheles spp. suggests structural and sequence similarity with potential antimalarial inhibitor [halofuginone (HF) and bicyclic azetidine (BRD1369)] binding sites. This suggests the potential for repurposing of these inhibitors against the studied Anopheles spp. and Ae. aegypti.
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Affiliation(s)
| | - Jyoti Chhibber-Goel
- Molecular Medicine, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Amit Sharma
- Molecular Medicine Group, National Institute of Malaria Research, New Delhi, India
- Molecular Medicine, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
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Mitasev B, Yang J, Gusovsky F, Girish D, Khile AS, Balla VS, Vikram V, Vaddi A, Bathula S, Sugandham SR, Terli C, Kalla V, Rayaprolu PK, Talabhakthula RK, Gotoda M, Melillo B, Schreiber SL, Fang FG. Crystallization-Based Synthetic Route to Antimalarial Agent BRD5018: Diazocene Ring Formation via a Staudinger-aza-Wittig Reaction on an Azetidine-Ribose Template. Org Process Res Dev 2021. [DOI: 10.1021/acs.oprd.1c00225] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Branko Mitasev
- G2D2 Eisai Inc., 35 Cambridgepark Drive, Cambridge, Massachusetts 02140, United States
| | - Jiong Yang
- G2D2 Eisai Inc., 35 Cambridgepark Drive, Cambridge, Massachusetts 02140, United States
| | - Fabian Gusovsky
- G2D2 Eisai Inc., 35 Cambridgepark Drive, Cambridge, Massachusetts 02140, United States
| | - Dixit Girish
- Eisai Pharmaceuticals India Pvt. Ltd., Ramky Pharma City, (SEZ), Plot Nos. 96, 97, 98, 124, &126, Parawada, Visakhapatnam, Andhra Pradesh 531019, India
| | - Anil Shahaji Khile
- Eisai Pharmaceuticals India Pvt. Ltd., Ramky Pharma City, (SEZ), Plot Nos. 96, 97, 98, 124, &126, Parawada, Visakhapatnam, Andhra Pradesh 531019, India
| | - Venkata Sasidhar Balla
- Eisai Pharmaceuticals India Pvt. Ltd., Ramky Pharma City, (SEZ), Plot Nos. 96, 97, 98, 124, &126, Parawada, Visakhapatnam, Andhra Pradesh 531019, India
| | - Venugopalarao Vikram
- Eisai Pharmaceuticals India Pvt. Ltd., Ramky Pharma City, (SEZ), Plot Nos. 96, 97, 98, 124, &126, Parawada, Visakhapatnam, Andhra Pradesh 531019, India
| | - Anand Vaddi
- Eisai Pharmaceuticals India Pvt. Ltd., Ramky Pharma City, (SEZ), Plot Nos. 96, 97, 98, 124, &126, Parawada, Visakhapatnam, Andhra Pradesh 531019, India
| | - Srikanth Bathula
- Eisai Pharmaceuticals India Pvt. Ltd., Ramky Pharma City, (SEZ), Plot Nos. 96, 97, 98, 124, &126, Parawada, Visakhapatnam, Andhra Pradesh 531019, India
| | - Srinivasa Rao Sugandham
- Eisai Pharmaceuticals India Pvt. Ltd., Ramky Pharma City, (SEZ), Plot Nos. 96, 97, 98, 124, &126, Parawada, Visakhapatnam, Andhra Pradesh 531019, India
| | - Chiranjeevi Terli
- Eisai Pharmaceuticals India Pvt. Ltd., Ramky Pharma City, (SEZ), Plot Nos. 96, 97, 98, 124, &126, Parawada, Visakhapatnam, Andhra Pradesh 531019, India
| | - Vijay Kalla
- Eisai Pharmaceuticals India Pvt. Ltd., Ramky Pharma City, (SEZ), Plot Nos. 96, 97, 98, 124, &126, Parawada, Visakhapatnam, Andhra Pradesh 531019, India
| | - Pavan Kumar Rayaprolu
- Eisai Pharmaceuticals India Pvt. Ltd., Ramky Pharma City, (SEZ), Plot Nos. 96, 97, 98, 124, &126, Parawada, Visakhapatnam, Andhra Pradesh 531019, India
| | - Ravi Kumar Talabhakthula
- Eisai Pharmaceuticals India Pvt. Ltd., Ramky Pharma City, (SEZ), Plot Nos. 96, 97, 98, 124, &126, Parawada, Visakhapatnam, Andhra Pradesh 531019, India
| | - Masaharu Gotoda
- Analytical Research Japan, Pharmaceutical Science & Technology, Medicine Development Center, Eisai Co. Ltd., 5-1-3-Tokodai, Tsukuba-shi, Ibaraki 300-2635, Japan
| | - Bruno Melillo
- Chemical Biology and Therapeutics Science Program, Broad Institute of Harvard and MIT, 415 Main Street, Cambridge, Massachusetts 02142, United States
- Department of Chemistry, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, California 92037, United States
| | - Stuart L. Schreiber
- Chemical Biology and Therapeutics Science Program, Broad Institute of Harvard and MIT, 415 Main Street, Cambridge, Massachusetts 02142, United States
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Francis G. Fang
- G2D2 Eisai Inc., 35 Cambridgepark Drive, Cambridge, Massachusetts 02140, United States
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Chhibber-Goel J, Yogavel M, Sharma A. Structural analyses of the malaria parasite aminoacyl-tRNA synthetases provide new avenues for antimalarial drug discovery. Protein Sci 2021; 30:1793-1803. [PMID: 34184352 DOI: 10.1002/pro.4148] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 06/12/2021] [Accepted: 06/22/2021] [Indexed: 11/10/2022]
Abstract
Malaria is a parasitic illness caused by the genus Plasmodium from the apicomplexan phylum. Five plasmodial species of P. falciparum (Pf), P. knowlesi, P. malariae, P. ovale, and P. vivax (Pv) are responsible for causing malaria in humans. According to the World Malaria Report 2020, there were 229 million cases and ~ 0.04 million deaths of which 67% were in children below 5 years of age. While more than 3 billion people are at risk of malaria infection globally, antimalarial drugs are their only option for treatment. Antimalarial drug resistance keeps arising periodically and thus threatens the main line of malaria treatment, emphasizing the need to find new alternatives. The availability of whole genomes of P. falciparum and P. vivax has allowed targeting their unexplored plasmodial enzymes for inhibitor development with a focus on multistage targets that are crucial for parasite viability in both the blood and liver stages. Over the past decades, aminoacyl-tRNA synthetases (aaRSs) have been explored as anti-bacterial and anti-fungal drug targets, and more recently (since 2009) aaRSs are also the focus of antimalarial drug targeting. Here, we dissect the structure-based knowledge of the most advanced three aaRSs-lysyl- (KRS), prolyl- (PRS), and phenylalanyl- (FRS) synthetases in terms of development of antimalarial drugs. These examples showcase the promising potential of this family of enzymes to provide druggable targets that stall protein synthesis upon inhibition and thereby kill malaria parasites selectively.
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Affiliation(s)
- Jyoti Chhibber-Goel
- Structural Parasitology Group, Molecular Medicine, International Center for Genetic Engineering and Biotechnology, New Delhi, India
| | - Manickam Yogavel
- Structural Parasitology Group, Molecular Medicine, International Center for Genetic Engineering and Biotechnology, New Delhi, India
| | - Amit Sharma
- Structural Parasitology Group, Molecular Medicine, International Center for Genetic Engineering and Biotechnology, New Delhi, India.,ICMR-National Institute of Malaria Research, New Delhi, India
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21
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Babbar P, Das P, Manickam Y, Mankad Y, Yadav S, Parvez S, Sharma A, Reddy DS. Design, Synthesis, and Structural Analysis of Cladosporin-Based Inhibitors of Malaria Parasites. ACS Infect Dis 2021; 7:1777-1794. [PMID: 33843204 DOI: 10.1021/acsinfecdis.1c00092] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Here we have described a systematic structure activity relationship (SAR) of a set of compounds inspired from cladosporin, a tool compound that targets parasite (Plasmodium falciparum) lysyl tRNA synthetase (KRS). Four sets of analogues, synthesized based on point changes in the chemical scaffold of cladosporin and other logical modifications and hybridizations, were assessed using high throughput enzymatic and parasitic assays along with in vitro pharmacokinetics. Co-crystallization of the most potent compound in our series (CL-2) with PfKRS revealed its structural basis of enzymatic binding and potency. Further, we report that CL-2 has performed better than cladosporin in terms of metabolic stability. It thus represents a new lead for further optimization toward the development of antimalarial drugs. Collectively, along with a lead compound, the series offers insights on how even the slightest chemical modification might play an important role in enhancing or decreasing the potency of a chemical scaffold.
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Affiliation(s)
- Palak Babbar
- Molecular Medicine−Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi 110067, India
- Department of Medical Elementology and Toxicology, School of Chemical and Life Sciences, Jamia Hamdard, New Delhi 110062, India
| | - Pronay Das
- Organic Chemistry Division, CSIR−National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Yogavel Manickam
- Molecular Medicine−Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Yash Mankad
- Organic Chemistry Division, CSIR−National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India
| | - Swati Yadav
- Organic Chemistry Division, CSIR−National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India
| | - Suhel Parvez
- Department of Medical Elementology and Toxicology, School of Chemical and Life Sciences, Jamia Hamdard, New Delhi 110062, India
| | - Amit Sharma
- Molecular Medicine−Structural Parasitology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi 110067, India
- ICMR−National Institute of Malaria Research, Sector 8, Dwarka, New Delhi 110077, India
| | - D. Srinivasa Reddy
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
- CSIR−Indian Institute of Integrative Medicine, Canal Road, Jammu 180001, India
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22
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Chaturvedi R, Chhibber-Goel J, Verma I, Gopinathan S, Parvez S, Sharma A. Geographical spread and structural basis of sulfadoxine-pyrimethamine drug-resistant malaria parasites. Int J Parasitol 2021; 51:505-525. [PMID: 33775670 DOI: 10.1016/j.ijpara.2020.12.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 11/24/2020] [Accepted: 12/03/2020] [Indexed: 12/22/2022]
Abstract
The global spread of sulfadoxine (Sdx, S) and pyrimethamine (Pyr, P) resistance is attributed to increasing number of mutations in DHPS and DHFR enzymes encoded by malaria parasites. The association between drug resistance mutations and SP efficacy is complex. Here we provide an overview of the geographical spread of SP resistance mutations in Plasmodium falciparum (Pf) and Plasmodium vivax (Pv) encoded dhps and dhfr genes. In addition, we have collated the mutation data and mapped it on to the three-dimensional structures of DHPS and DHFR which have become available. Data from genomic databases and 286 studies were collated to provide a comprehensive landscape of mutational data from 2005 to 2019. Our analyses show that the Pyr-resistant double mutations are widespread in Pf/PvDHFR (P. falciparum ∼61% in Asia and the Middle East, and in the Indian sub-continent; in P. vivax ∼33% globally) with triple mutations prevailing in Africa (∼66%) and South America (∼33%). For PfDHPS, triple mutations dominate South America (∼44%), Asia and the Middle East (∼34%) and the Indian sub-continent (∼27%), while single mutations are widespread in Africa (∼45%). Contrary to the status for P. falciparum, Sdx-resistant single point mutations in PvDHPS dominate globally. Alarmingly, highly resistant quintuple and sextuple mutations are rising in Africa (PfDHFR-DHPS) and Asia (Pf/PvDHFR-DHPS). Structural analyses of DHFR and DHPS proteins in complexes with substrates/drugs have revealed that resistance mutations map proximal to Sdx and Pyr binding sites. Thus new studies can focus on discovery of novel inhibitors that target the non-substrate binding grooves in these two validated malaria parasite drug targets.
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Affiliation(s)
- Rini Chaturvedi
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India; Department of Toxicology, Jamia Hamdard, New Delhi, India
| | - Jyoti Chhibber-Goel
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Ishika Verma
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Sreehari Gopinathan
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Suhel Parvez
- Department of Toxicology, Jamia Hamdard, New Delhi, India
| | - Amit Sharma
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India; National Institute of Malaria Research, Dwarka, New Delhi, India.
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