1
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Legru A, Batista FA, Puszko AK, Bouillon A, Maurel M, Martinez M, Ejjoummany A, Ortega Varga L, Adler P, Méchaly A, Hadjadj M, Sosnowski P, Hopfgartner G, Alzari PM, Blondel A, Haouz A, Barale JC, Hernandez JF. Insights from structure-activity relationships and the binding mode of peptidic α-ketoamide inhibitors of the malaria drug target subtilisin-like SUB1. Eur J Med Chem 2024; 269:116308. [PMID: 38503166 DOI: 10.1016/j.ejmech.2024.116308] [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: 12/11/2023] [Revised: 03/04/2024] [Accepted: 03/04/2024] [Indexed: 03/21/2024]
Abstract
Plasmodium multi-resistance, including against artemisinin, seriously threatens malaria treatment and control. Hence, new drugs are urgently needed, ideally targeting different parasitic stages, which are not yet targeted by current drugs. The SUB1 protease is involved in both hepatic and blood stages due to its essential role in the egress of parasites from host cells, and, as potential new target, it would meet the above criteria. We report here the synthesis as well as the biological and structural evaluation of substrate-based α-ketoamide SUB1 pseudopeptidic inhibitors encompassing positions P4-P2'. By individually substituting each position of the reference compound 1 (MAM-117, Ac-Ile-Thr-Ala-AlaCO-Asp-Glu (Oall)-NH2), we better characterized the structural determinants for SUB1 binding. We first identified compound 8 with IC50 values of 50 and 570 nM against Pv- and PfSUB1, respectively (about 3.5-fold higher potency compared to 1). Compound 8 inhibited P. falciparum merozoite egress in culture by 37% at 100 μM. By increasing the overall hydrophobicity of the compounds, we could improve the PfSUB1 inhibition level and antiparasitic activity, as shown with compound 40 (IC50 values of 12 and 10 nM against Pv- and PfSUB1, respectively, IC50 value of 23 μM on P. falciparum merozoite egress). We also found that 8 was highly selective towards SUB1 over three mammalian serine peptidases, supporting the promising value of this compound. Finally, several crystal 3D-structures of SUB1-inhibitor complexes, including with 8, were solved at high resolution to decipher the binding mode of these compounds.
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Affiliation(s)
- Alice Legru
- Institut des Biomolécules Max Mousseron (IBMM), CNRS, Univ Montpellier, ENSCM, Montpellier, France
| | - Fernando A Batista
- Structural Microbiology, UMR3528, Institut Pasteur, CNRS, Université de Paris, Paris, France
| | - Anna K Puszko
- Institut des Biomolécules Max Mousseron (IBMM), CNRS, Univ Montpellier, ENSCM, Montpellier, France
| | - Anthony Bouillon
- Structural Microbiology, UMR3528, Institut Pasteur, CNRS, Université de Paris, Paris, France
| | - Manon Maurel
- Institut des Biomolécules Max Mousseron (IBMM), CNRS, Univ Montpellier, ENSCM, Montpellier, France
| | - Mariano Martinez
- Structural Microbiology, UMR3528, Institut Pasteur, CNRS, Université de Paris, Paris, France
| | - Abdelaziz Ejjoummany
- Institut des Biomolécules Max Mousseron (IBMM), CNRS, Univ Montpellier, ENSCM, Montpellier, France
| | - Laura Ortega Varga
- Structural Bioinformatic, UMR3528, Institut Pasteur, CNRS, Université de Paris, Paris, France
| | - Pauline Adler
- Institut des Biomolécules Max Mousseron (IBMM), CNRS, Univ Montpellier, ENSCM, Montpellier, France
| | - Ariel Méchaly
- Cristallography Platform-C2RT, UMR3528, Institut Pasteur, CNRS, Université de Paris, Paris, France
| | - Margot Hadjadj
- Institut des Biomolécules Max Mousseron (IBMM), CNRS, Univ Montpellier, ENSCM, Montpellier, France
| | - Piotr Sosnowski
- Department of Inorganic and Analytical Chemistry, University of Geneva, CH-1211, Geneva, Switzerland
| | - Gérard Hopfgartner
- Department of Inorganic and Analytical Chemistry, University of Geneva, CH-1211, Geneva, Switzerland
| | - Pedro M Alzari
- Structural Microbiology, UMR3528, Institut Pasteur, CNRS, Université de Paris, Paris, France
| | - Arnaud Blondel
- Structural Bioinformatic, UMR3528, Institut Pasteur, CNRS, Université de Paris, Paris, France
| | - Ahmed Haouz
- Cristallography Platform-C2RT, UMR3528, Institut Pasteur, CNRS, Université de Paris, Paris, France
| | - Jean-Christophe Barale
- Structural Microbiology, UMR3528, Institut Pasteur, CNRS, Université de Paris, Paris, France.
| | - Jean-François Hernandez
- Institut des Biomolécules Max Mousseron (IBMM), CNRS, Univ Montpellier, ENSCM, Montpellier, France.
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2
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Martinez M, Bouillon A, Brûlé S, Raynal B, Haouz A, Alzari PM, Barale JC. Prodomain-driven enzyme dimerization: a pH-dependent autoinhibition mechanism that controls Plasmodium Sub1 activity before merozoite egress. mBio 2024; 15:e0019824. [PMID: 38386597 PMCID: PMC10936178 DOI: 10.1128/mbio.00198-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Accepted: 01/31/2024] [Indexed: 02/24/2024] Open
Abstract
Malaria symptoms are associated with the asexual multiplication of Plasmodium falciparum within human red blood cells (RBCs) and fever peaks coincide with the egress of daughter merozoites following the rupture of the parasitophorous vacuole (PV) and the RBC membranes. Over the last two decades, it has emerged that the release of competent merozoites is tightly regulated by a complex cascade of events, including the unusual multi-step activation mechanism of the pivotal subtilisin-like protease 1 (Sub1) that takes place in three different cellular compartments and remains poorly understood. Following an initial auto-maturation in the endoplasmic reticulum (ER) between its pro- and catalytic domains, the Sub1 prodomain (PD) undergoes further cleavages by the parasite aspartic protease plasmepsin X (PmX) within acidic secretory organelles that ultimately lead to full Sub1 activation upon discharge into the PV. Here, we report the crystal structure of full-length P. falciparum Sub1 (PfS1FL) and demonstrate, through structural, biochemical, and biophysical studies, that the atypical Plasmodium-specific Sub1 PD directly promotes the assembly of inactive enzyme homodimers at acidic pH, whereas Sub1 is primarily monomeric at neutral pH. Our results shed new light into the finely tuned Sub1 spatiotemporal activation during secretion, explaining how PmX processing and full activation of Sub1 can occur in different cellular compartments, and uncover a robust mechanism of pH-dependent subtilisin autoinhibition that plays a key role in P. falciparum merozoites egress from infected host cells.IMPORTANCEMalaria fever spikes are due to the rupture of infected erythrocytes, allowing the egress of Plasmodium sp. merozoites and further parasite propagation. This fleeting tightly regulated event involves a cascade of enzymes, culminating with the complex activation of the subtilisin-like protease 1, Sub1. Differently than other subtilisins, Sub1 activation strictly depends upon the processing by a parasite aspartic protease within acidic merozoite secretory organelles. However, Sub1 biological activity is required in the pH neutral parasitophorous vacuole, to prime effectors involved in the rupture of the vacuole and erythrocytic membranes. Here, we show that the unusual, parasite-specific Sub1 prodomain is directly responsible for its acidic-dependent dimerization and autoinhibition, required for protein secretion, before its full activation at neutral pH in a monomeric form. pH-dependent Sub1 dimerization defines a novel, essential regulatory element involved in the finely tuned spatiotemporal activation of the egress of competent Plasmodium merozoites.
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Affiliation(s)
- Mariano Martinez
- Unité de Microbiologie Structurale, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, Paris, France
| | - Anthony Bouillon
- Unité de Microbiologie Structurale, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, Paris, France
| | - Sébastien Brûlé
- Plate-forme de Biophysique Moleculaire-C2RT, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, Paris, France
| | - Bertrand Raynal
- Plate-forme de Biophysique Moleculaire-C2RT, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, Paris, France
| | - Ahmed Haouz
- Plate-forme de Cristallographie-C2RT, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, Paris, France
| | - Pedro M. Alzari
- Unité de Microbiologie Structurale, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, Paris, France
| | - Jean-Christophe Barale
- Unité de Microbiologie Structurale, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, Paris, France
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3
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Mairet-Khedim M, Roesch C, Khim N, Srun S, Bouillon A, Kim S, Ke S, Kauy C, Kloeung N, Eam R, Khean C, Kul C, Chy S, Leang R, Ringwald P, Barale JC, Witkowski B. Prevalence and characterization of piperaquine, mefloquine and artemisinin derivatives triple-resistant Plasmodium falciparum in Cambodia. J Antimicrob Chemother 2022; 78:411-417. [PMID: 36508338 PMCID: PMC9890270 DOI: 10.1093/jac/dkac403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 10/31/2022] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND In early 2016, in Preah Vihear, Northern Cambodia, artesunate/mefloquine was used to cope with dihydroartemisinin/piperaquine-resistant Plasmodium falciparum parasites. Following this policy, P. falciparum strains harbouring molecular markers associated with artemisinin, piperaquine and mefloquine resistance have emerged. However, the lack of a viable alternative led Cambodia to adopt artesunate/mefloquine countrywide, raising concerns about a surge of triple-resistant P. falciparum strains. OBJECTIVES To assess the prevalence of triple-resistant parasites after artesunate/mefloquine implementation countrywide in Cambodia and to characterize their phenotype. METHODS For this multicentric study, 846 samples were collected from 2016 to 2019. Genotyping of molecular markers associated with artemisinin, piperaquine and mefloquine resistance was coupled with phenotypic analyses. RESULTS Only four triple-resistant P. falciparum isolates (0.47%) were identified during the study period. These parasites combined the pfk13 polymorphism with pfmdr1 amplification, pfpm2 amplification and/or pfcrt mutations. They showed significantly higher tolerance to artemisinin, piperaquine and mefloquine and also to the mefloquine and piperaquine combination. CONCLUSIONS The use of artesunate/mefloquine countrywide in Cambodia has not led to a massive increase of triple-resistant P. falciparum parasites. However, these parasites circulate in the population, and exhibit clear resistance to piperaquine, mefloquine and their combination in vitro. This study demonstrates that P. falciparum can adapt to more complex drug associations, which should be considered in future therapeutic designs.
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Affiliation(s)
| | | | - Nimol Khim
- Institut Pasteur, Pasteur International Unit, Pasteur International Network, Malaria Translational Research Unit, Phnom Penh, Cambodia and Paris, France,Malaria Molecular Epidemiology Unit, Pasteur Institute of Cambodia, Phnom Penh, Cambodia
| | - Sreynet Srun
- Institut Pasteur, Pasteur International Unit, Pasteur International Network, Malaria Translational Research Unit, Phnom Penh, Cambodia and Paris, France,Malaria Molecular Epidemiology Unit, Pasteur Institute of Cambodia, Phnom Penh, Cambodia
| | - Anthony Bouillon
- Institut Pasteur, Université Paris Cité, CNRS UMR3528, Unité de Microbiologie Structurale, F-75015 Paris, France,Institut Pasteur, Pasteur International Unit, Pasteur International Network, Malaria Translational Research Unit, Phnom Penh, Cambodia and Paris, France
| | - Saorin Kim
- Institut Pasteur, Pasteur International Unit, Pasteur International Network, Malaria Translational Research Unit, Phnom Penh, Cambodia and Paris, France,Malaria Molecular Epidemiology Unit, Pasteur Institute of Cambodia, Phnom Penh, Cambodia
| | - Sopheakvatey Ke
- Institut Pasteur, Pasteur International Unit, Pasteur International Network, Malaria Translational Research Unit, Phnom Penh, Cambodia and Paris, France,Malaria Molecular Epidemiology Unit, Pasteur Institute of Cambodia, Phnom Penh, Cambodia
| | - Chhayleang Kauy
- Institut Pasteur, Pasteur International Unit, Pasteur International Network, Malaria Translational Research Unit, Phnom Penh, Cambodia and Paris, France,Malaria Molecular Epidemiology Unit, Pasteur Institute of Cambodia, Phnom Penh, Cambodia
| | - Nimol Kloeung
- Institut Pasteur, Pasteur International Unit, Pasteur International Network, Malaria Translational Research Unit, Phnom Penh, Cambodia and Paris, France,Malaria Molecular Epidemiology Unit, Pasteur Institute of Cambodia, Phnom Penh, Cambodia
| | - Rotha Eam
- Institut Pasteur, Pasteur International Unit, Pasteur International Network, Malaria Translational Research Unit, Phnom Penh, Cambodia and Paris, France,Malaria Molecular Epidemiology Unit, Pasteur Institute of Cambodia, Phnom Penh, Cambodia
| | - Chanra Khean
- Institut Pasteur, Pasteur International Unit, Pasteur International Network, Malaria Translational Research Unit, Phnom Penh, Cambodia and Paris, France,Malaria Molecular Epidemiology Unit, Pasteur Institute of Cambodia, Phnom Penh, Cambodia
| | - Chanvong Kul
- Institut Pasteur, Pasteur International Unit, Pasteur International Network, Malaria Translational Research Unit, Phnom Penh, Cambodia and Paris, France,Malaria Molecular Epidemiology Unit, Pasteur Institute of Cambodia, Phnom Penh, Cambodia
| | - Sophy Chy
- Institut Pasteur, Pasteur International Unit, Pasteur International Network, Malaria Translational Research Unit, Phnom Penh, Cambodia and Paris, France,Malaria Molecular Epidemiology Unit, Pasteur Institute of Cambodia, Phnom Penh, Cambodia
| | - Rithea Leang
- National Centre for Malariology, Entomology and Malaria Control, Phnom Penh, Cambodia
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4
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Lidumniece E, Withers-Martinez C, Hackett F, Blackman MJ, Jirgensons A. Subtilisin-like Serine Protease 1 (SUB1) as an Emerging Antimalarial Drug Target: Current Achievements in Inhibitor Discovery. J Med Chem 2022; 65:12535-12545. [PMID: 36137276 DOI: 10.1021/acs.jmedchem.2c01093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Widespread resistance to many antimalarial therapies currently in use stresses the need for the discovery of new classes of drugs with new modes of action. The subtilisin-like serine protease SUB1 controls egress of malaria parasites (merozoites) from the parasite-infected red blood cell. As such, SUB1 is considered a prospective target for drugs designed to interrupt the asexual blood stage life cycle of the malaria parasite. Inhibitors of SUB1 have potential as wide-spectrum antimalarial drugs, as a single orthologue of SUB1 is found in the genomes of all known Plasmodium species. This mini-perspective provides a short overview of the function and structure of SUB1 and summarizes all of the published SUB1 inhibitors. The inhibitors are classified by the methods of their discovery, including both rational design and screening.
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Affiliation(s)
| | | | - Fiona Hackett
- Malaria Biochemistry Laboratory, The Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Michael J Blackman
- Malaria Biochemistry Laboratory, The Francis Crick Institute, London NW1 1AT, United Kingdom.,Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London WC1E 7HT, United Kingdom
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5
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Peptidic boronic acids are potent cell-permeable inhibitors of the malaria parasite egress serine protease SUB1. Proc Natl Acad Sci U S A 2021; 118:2022696118. [PMID: 33975947 PMCID: PMC8157947 DOI: 10.1073/pnas.2022696118] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Malaria is a devastating infectious disease, which causes over 400,000 deaths per annum and impacts the lives of nearly half the world's population. The causative agent, a protozoan parasite, replicates within red blood cells (RBCs), eventually destroying the cells in a lytic process called egress to release a new generation of parasites. These invade fresh RBCs to repeat the cycle. Egress is regulated by an essential parasite subtilisin-like serine protease called SUB1. Here, we describe the development and optimization of substrate-based peptidic boronic acids that inhibit Plasmodium falciparum SUB1 with low nanomolar potency. Structural optimization generated membrane-permeable, slow off-rate inhibitors that prevent Pfalciparum egress through direct inhibition of SUB1 activity and block parasite replication in vitro at submicromolar concentrations. Our results validate SUB1 as a potential target for a new class of antimalarial drugs designed to prevent parasite replication and disease progression.
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6
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Burns AL, Dans MG, Balbin JM, de Koning-Ward TF, Gilson PR, Beeson JG, Boyle MJ, Wilson DW. Targeting malaria parasite invasion of red blood cells as an antimalarial strategy. FEMS Microbiol Rev 2019; 43:223-238. [PMID: 30753425 PMCID: PMC6524681 DOI: 10.1093/femsre/fuz005] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Accepted: 02/11/2019] [Indexed: 12/20/2022] Open
Abstract
Plasmodium spp. parasites that cause malaria disease remain a significant global-health burden. With the spread of parasites resistant to artemisinin combination therapies in Southeast Asia, there is a growing need to develop new antimalarials with novel targets. Invasion of the red blood cell by Plasmodium merozoites is essential for parasite survival and proliferation, thus representing an attractive target for therapeutic development. Red blood cell invasion requires a co-ordinated series of protein/protein interactions, protease cleavage events, intracellular signals, organelle release and engagement of an actin-myosin motor, which provide many potential targets for drug development. As these steps occur in the bloodstream, they are directly susceptible and exposed to drugs. A number of invasion inhibitors against a diverse range of parasite proteins involved in these different processes of invasion have been identified, with several showing potential to be optimised for improved drug-like properties. In this review, we discuss red blood cell invasion as a drug target and highlight a number of approaches for developing antimalarials with invasion inhibitory activity to use in future combination therapies.
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Affiliation(s)
- Amy L Burns
- Research Centre for Infectious Diseases, School of Biological Sciences, University of Adelaide, Adelaide, Australia 5005
| | - Madeline G Dans
- Burnet Institute, Melbourne, Victoria, Australia 3004.,Deakin University, School of Medicine, Waurn Ponds, Victoria, Australia 3216
| | - Juan M Balbin
- Research Centre for Infectious Diseases, School of Biological Sciences, University of Adelaide, Adelaide, Australia 5005
| | | | - Paul R Gilson
- Burnet Institute, Melbourne, Victoria, Australia 3004
| | - James G Beeson
- Burnet Institute, Melbourne, Victoria, Australia 3004.,Central Clinical School and Department of Microbiology, Monash University 3004.,Department of Medicine, University of Melbourne, Australia 3052
| | - Michelle J Boyle
- Burnet Institute, Melbourne, Victoria, Australia 3004.,QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia 4006
| | - Danny W Wilson
- Research Centre for Infectious Diseases, School of Biological Sciences, University of Adelaide, Adelaide, Australia 5005.,Burnet Institute, Melbourne, Victoria, Australia 3004
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7
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Chen JH, Chen SB, Wang Y, Ju C, Zhang T, Xu B, Shen HM, Mo XJ, Molina DM, Eng M, Liang X, Gardner MJ, Wang R, Hu W. An immunomics approach for the analysis of natural antibody responses to Plasmodium vivax infection. MOLECULAR BIOSYSTEMS 2016; 11:2354-63. [PMID: 26091354 DOI: 10.1039/c5mb00330j] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
High throughput immunomics is a powerful platform to discover potential targets of host immunity and develop diagnostic tests for infectious diseases. We screened the sera of Plasmodium vivax-exposed individuals to profile the antibody response to blood-stage antigens of P. vivax using a P. vivax protein microarray. A total of 1936 genes encoding the P. vivax proteins were expressed, printed and screened with sera from P. vivax-exposed individuals and normal subjects. Total of 151 (7.8% of the 1936 targets) highly immunoreactive antigens were identified, including five well-characterized antigens of P. vivax (ETRAMP11.2, Pv34, SUB1, RAP2 and MSP4). Among the highly immunoreactive antigens, 5 antigens were predicted as adhesins by MAAP, and 11 antigens were predicted as merozoite invasion-related proteins based on homology with P. falciparum proteins. There are 40 proteins that have serodiagnostic potential for antibody surveillance. These novel Plasmodium antigens identified provide the clues for understanding host immune response to P. vivax infection and the development of antibody surveillance tools.
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Affiliation(s)
- Jun-Hu Chen
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health, WHO Collaborating Center for Malaria, Schistosomiasis and Filariasis, Shanghai 200025, People's Republic of China.
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8
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Njogu PM, Guantai EM, Pavadai E, Chibale K. Computer-Aided Drug Discovery Approaches against the Tropical Infectious Diseases Malaria, Tuberculosis, Trypanosomiasis, and Leishmaniasis. ACS Infect Dis 2016; 2:8-31. [PMID: 27622945 DOI: 10.1021/acsinfecdis.5b00093] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Despite the tremendous improvement in overall global health heralded by the adoption of the Millennium Declaration in the year 2000, tropical infections remain a major health problem in the developing world. Recent estimates indicate that the major tropical infectious diseases, namely, malaria, tuberculosis, trypanosomiasis, and leishmaniasis, account for more than 2.2 million deaths and a loss of approximately 85 million disability-adjusted life years annually. The crucial role of chemotherapy in curtailing the deleterious health and economic impacts of these infections has invigorated the search for new drugs against tropical infectious diseases. The research efforts have involved increased application of computational technologies in mainstream drug discovery programs at the hit identification, hit-to-lead, and lead optimization stages. This review highlights various computer-aided drug discovery approaches that have been utilized in efforts to identify novel antimalarial, antitubercular, antitrypanosomal, and antileishmanial agents. The focus is largely on developments over the past 5 years (2010-2014).
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Affiliation(s)
- Peter M. Njogu
- Department of Pharmaceutical Chemistry and ‡Division of Pharmacology, School of Pharmacy, University of Nairobi, P.O. Box 19676-00202, Nairobi, Kenya
- Department of Chemistry, ⊗Institute of Infectious
Disease and Molecular Medicine, and ΘSouth African Medical Research Council Drug
Discovery and Development Research Unit, University of Cape Town, Rondebosch 7701, South Africa
| | - Eric M. Guantai
- Department of Pharmaceutical Chemistry and ‡Division of Pharmacology, School of Pharmacy, University of Nairobi, P.O. Box 19676-00202, Nairobi, Kenya
- Department of Chemistry, ⊗Institute of Infectious
Disease and Molecular Medicine, and ΘSouth African Medical Research Council Drug
Discovery and Development Research Unit, University of Cape Town, Rondebosch 7701, South Africa
| | - Elumalai Pavadai
- Department of Pharmaceutical Chemistry and ‡Division of Pharmacology, School of Pharmacy, University of Nairobi, P.O. Box 19676-00202, Nairobi, Kenya
- Department of Chemistry, ⊗Institute of Infectious
Disease and Molecular Medicine, and ΘSouth African Medical Research Council Drug
Discovery and Development Research Unit, University of Cape Town, Rondebosch 7701, South Africa
| | - Kelly Chibale
- Department of Pharmaceutical Chemistry and ‡Division of Pharmacology, School of Pharmacy, University of Nairobi, P.O. Box 19676-00202, Nairobi, Kenya
- Department of Chemistry, ⊗Institute of Infectious
Disease and Molecular Medicine, and ΘSouth African Medical Research Council Drug
Discovery and Development Research Unit, University of Cape Town, Rondebosch 7701, South Africa
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9
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Han JH, Li J, Wang B, Lee SK, Nyunt MH, Na S, Park JH, Han ET. Identification of Immunodominant B-cell Epitope Regions of Reticulocyte Binding Proteins in Plasmodium vivax by Protein Microarray Based Immunoscreening. THE KOREAN JOURNAL OF PARASITOLOGY 2015; 53:403-11. [PMID: 26323838 PMCID: PMC4566507 DOI: 10.3347/kjp.2015.53.4.403] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Revised: 07/23/2015] [Accepted: 07/23/2015] [Indexed: 11/23/2022]
Abstract
Plasmodium falciparum can invade all stages of red blood cells, while Plasmodium vivax can invade only reticulocytes. Although many P. vivax proteins have been discovered, their functions are largely unknown. Among them, P. vivax reticulocyte binding proteins (PvRBP1 and PvRBP2) recognize and bind to reticulocytes. Both proteins possess a C-terminal hydrophobic transmembrane domain, which drives adhesion to reticulocytes. PvRBP1 and PvRBP2 are large (> 326 kDa), which hinders identification of the functional domains. In this study, the complete genome information of the P. vivax RBP family was thoroughly analyzed using a prediction server with bioinformatics data to predict B-cell epitope domains. Eleven pvrbp family genes that included 2 pseudogenes and 9 full or partial length genes were selected and used to express recombinant proteins in a wheat germ cell-free system. The expressed proteins were used to evaluate the humoral immune response with vivax malaria patients and healthy individual serum samples by protein microarray. The recombinant fragments of 9 PvRBP proteins were successfully expressed; the soluble proteins ranged in molecular weight from 16 to 34 kDa. Evaluation of the humoral immune response to each recombinant PvRBP protein indicated a high antigenicity, with 38-88% sensitivity and 100% specificity. Of them, N-terminal parts of PvRBP2c (PVX_090325-1) and PvRBP2 like partial A (PVX_090330-1) elicited high antigenicity. In addition, the PvRBP2-like homologue B (PVX_116930) fragment was newly identified as high antigenicity and may be exploited as a potential antigenic candidate among the PvRBP family. The functional activity of the PvRBP family on merozoite invasion remains unknown.
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Affiliation(s)
- Jin-Hee Han
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon 200-701, Korea
| | - Jian Li
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon 200-701, Korea.,Department of Parasitology, College of Basic Medicine, Hubei University of Medicine, Shiyan, Hubei 442000, China
| | - Bo Wang
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon 200-701, Korea.,Department of Clinical Laboratory, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, People's Republic of China
| | - Seong-Kyun Lee
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon 200-701, Korea
| | - Myat Htut Nyunt
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon 200-701, Korea.,Department of Medical Research, Yangon, Myanmar
| | - Sunghun Na
- Department of Obstetrics and Gynecology, School of Medicine, Kangwon National University, Chuncheon 200-701, Korea
| | - Jeong-Hyun Park
- Department of Anatomy, School of Medicine, Kangwon National University, Chuncheon 200-701, Korea
| | - Eun-Taek Han
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon 200-701, Korea
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11
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Bastianelli G, Bouillon A, Nguyen C, Le-Nguyen D, Nilges M, Barale JC. Computational design of protein-based inhibitors of Plasmodium vivax subtilisin-like 1 protease. PLoS One 2014; 9:e109269. [PMID: 25343504 PMCID: PMC4208747 DOI: 10.1371/journal.pone.0109269] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Accepted: 08/16/2014] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Malaria remains a major global health concern. The development of novel therapeutic strategies is critical to overcome the selection of multiresistant parasites. The subtilisin-like protease (SUB1) involved in the egress of daughter Plasmodium parasites from infected erythrocytes and in their subsequent invasion into fresh erythrocytes has emerged as an interesting new drug target. FINDINGS Using a computational approach based on homology modeling, protein-protein docking and mutation scoring, we designed protein-based inhibitors of Plasmodium vivax SUB1 (PvSUB1) and experimentally evaluated their inhibitory activity. The small peptidic trypsin inhibitor EETI-II was used as scaffold. We mutated residues at specific positions (P4 and P1) and calculated the change in free-energy of binding with PvSUB1. In agreement with our predictions, we identified a mutant of EETI-II (EETI-II-P4LP1W) with a Ki in the medium micromolar range. CONCLUSIONS Despite the challenges related to the lack of an experimental structure of PvSUB1, the computational protocol we developed in this study led to the design of protein-based inhibitors of PvSUB1. The approach we describe in this paper, together with other examples, demonstrates the capabilities of computational procedures to accelerate and guide the design of novel proteins with interesting therapeutic applications.
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Affiliation(s)
- Giacomo Bastianelli
- Institut Pasteur, Unité de Bioinformatique Structurale, Département de Biologie Structurale et Chimie, Paris, France
- CNRS UMR 3528, Paris, France
| | - Anthony Bouillon
- Institut Pasteur, Unité d’Immunologie Moléculaires des Parasites, Département de Parasitologie et de Mycologie & CNRS URA 2581, Paris, France
- CNRS, URA2581, Paris, France
| | | | | | - Michael Nilges
- Institut Pasteur, Unité de Bioinformatique Structurale, Département de Biologie Structurale et Chimie, Paris, France
- CNRS UMR 3528, Paris, France
| | - Jean-Christophe Barale
- Institut Pasteur, Unité d’Immunologie Moléculaires des Parasites, Département de Parasitologie et de Mycologie & CNRS URA 2581, Paris, France
- CNRS, URA2581, Paris, France
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12
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Moine E, Denevault-Sabourin C, Debierre-Grockiego F, Silpa L, Gorgette O, Barale JC, Jacquiet P, Brossier F, Gueiffier A, Dimier-Poisson I, Enguehard-Gueiffier C. A small-molecule cell-based screen led to the identification of biphenylimidazoazines with highly potent and broad-spectrum anti-apicomplexan activity. Eur J Med Chem 2014; 89:386-400. [PMID: 25462254 DOI: 10.1016/j.ejmech.2014.10.057] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 10/17/2014] [Accepted: 10/18/2014] [Indexed: 10/24/2022]
Abstract
An in vitro screening of the anti-apicomplexan activity of 51 compounds, stemming from our chemical library and from chemical synthesis, was performed. As a study model, we used Toxoplasma gondii (T. gondii), expressing β-galactosidase for the colorimetric assessment of drug activity on parasites cultivated in vitro. This approach allowed the validation of a new series of molecules with a biphenylimidazoazine scaffold as inhibitors of T. gondii growth in vitro. Hence, 8 molecules significantly inhibited intracellular replication of T. gondii in vitro, with EC50 < 1 μM, while being non-toxic for human fibroblasts at these concentrations. Most attractive candidates were then selected for further biological investigations on other apicomplexan parasites (Neospora caninum, Besnoitia besnoiti, Eimeria tenella and Plasmodium falciparum). Finally, two compounds were able to inhibit growth of four different apicomplexans with EC50 in the submicromolar to nanomolar range, for each parasite. These data, including the broad anti-parasite spectrum of these inhibitors, define a new generation of potential anti-parasite compounds of wide interest, including for veterinary application. Studies realized on E. tenella suggest that these molecules act during the intracellular development steps of the parasite. Further experiments should be done to identify the molecular target(s) of these compounds.
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Affiliation(s)
- Espérance Moine
- UMR INRA 1282 Infectiologie et Santé Publique, Recherche et Innovation en Chimie Médicinale, University François Rabelais of Tours, F-37200 Tours, France; UMR INRA 1282 Infectiologie et Santé Publique, Immunologie Parasitaire, Vaccinologie et Bio-thérapie Anti-infectieuse, University François Rabelais of Tours, F-37200 Tours, France
| | - Caroline Denevault-Sabourin
- UMR INRA 1282 Infectiologie et Santé Publique, Recherche et Innovation en Chimie Médicinale, University François Rabelais of Tours, F-37200 Tours, France.
| | - Françoise Debierre-Grockiego
- UMR INRA 1282 Infectiologie et Santé Publique, Immunologie Parasitaire, Vaccinologie et Bio-thérapie Anti-infectieuse, University François Rabelais of Tours, F-37200 Tours, France
| | - Laurence Silpa
- UMR INRA 1282 Infectiologie et Santé Publique, Recherche et Innovation en Chimie Médicinale, University François Rabelais of Tours, F-37200 Tours, France; UMR INRA 1282 Infectiologie et Santé Publique, Apicomplexes et Immunité des Muqueuses, INRA, F-37380 Nouzilly, France
| | - Olivier Gorgette
- Institut Pasteur, Unité d'Immunologie Moléculaire des Parasites, Département de Parasitologie et de Mycologie, F-75015 Paris, France
| | - Jean-Christophe Barale
- Institut Pasteur, Unité d'Immunologie Moléculaire des Parasites, Département de Parasitologie et de Mycologie, F-75015 Paris, France
| | - Philippe Jacquiet
- UMR 1225 INRA-National Veterinary School of Toulouse, Interactions hôtes-agents pathogènes, F-31076 Toulouse, France
| | - Fabien Brossier
- UMR INRA 1282 Infectiologie et Santé Publique, Apicomplexes et Immunité des Muqueuses, INRA, F-37380 Nouzilly, France
| | - Alain Gueiffier
- UMR INRA 1282 Infectiologie et Santé Publique, Recherche et Innovation en Chimie Médicinale, University François Rabelais of Tours, F-37200 Tours, France
| | - Isabelle Dimier-Poisson
- UMR INRA 1282 Infectiologie et Santé Publique, Immunologie Parasitaire, Vaccinologie et Bio-thérapie Anti-infectieuse, University François Rabelais of Tours, F-37200 Tours, France
| | - Cécile Enguehard-Gueiffier
- UMR INRA 1282 Infectiologie et Santé Publique, Recherche et Innovation en Chimie Médicinale, University François Rabelais of Tours, F-37200 Tours, France
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13
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Giganti D, Bouillon A, Tawk L, Robert F, Martinez M, Crublet E, Weber P, Girard-Blanc C, Petres S, Haouz A, Hernandez JF, Mercereau-Puijalon O, Alzari PM, Barale JC. A novel Plasmodium-specific prodomain fold regulates the malaria drug target SUB1 subtilase. Nat Commun 2014; 5:4833. [PMID: 25204226 DOI: 10.1038/ncomms5833] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 07/29/2014] [Indexed: 11/09/2022] Open
Abstract
The Plasmodium subtilase SUB1 plays a pivotal role during the egress of malaria parasites from host hepatocytes and erythrocytes. Here we report the crystal structure of full-length SUB1 from the human-infecting parasite Plasmodium vivax, revealing a bacterial-like catalytic domain in complex with a Plasmodium-specific prodomain. The latter displays a novel architecture with an amino-terminal insertion that functions as a 'belt', embracing the catalytic domain to further stabilize the quaternary structure of the pre-protease, and undergoes calcium-dependent autoprocessing during subsequent activation. Although dispensable for recombinant enzymatic activity, the SUB1 'belt' could not be deleted in Plasmodium berghei, suggesting an essential role of this domain for parasite development in vivo. The SUB1 structure not only provides a valuable platform to develop new anti-malarial candidates against this promising drug target, but also defines the Plasmodium-specific 'belt' domain as a key calcium-dependent regulator of SUB1 during parasite egress from host cells.
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Affiliation(s)
- David Giganti
- 1] Institut Pasteur, Unité de Microbiologie Structurale, Département de Biologie Structurale et Chimie, F-75015 Paris, France [2] CNRS UMR 3528, F-75015 Paris, France
| | - Anthony Bouillon
- 1] Institut Pasteur, Unité d'Immunologie Moléculaires des Parasites, Département de Parasitologie et de Mycologie, F-75015 Paris, France [2] CNRS URA 2581, F-75015 Paris, France
| | - Lina Tawk
- 1] Institut Pasteur, Unité d'Immunologie Moléculaires des Parasites, Département de Parasitologie et de Mycologie, F-75015 Paris, France [2] CNRS URA 2581, F-75015 Paris, France
| | - Fabienne Robert
- 1] Institut Pasteur, Unité d'Immunologie Moléculaires des Parasites, Département de Parasitologie et de Mycologie, F-75015 Paris, France [2] CNRS URA 2581, F-75015 Paris, France
| | - Mariano Martinez
- 1] Institut Pasteur, Unité de Microbiologie Structurale, Département de Biologie Structurale et Chimie, F-75015 Paris, France [2] CNRS UMR 3528, F-75015 Paris, France
| | - Elodie Crublet
- Institut Pasteur, Proteopole &CNRS UMR 3528, F-75015 Paris, France
| | - Patrick Weber
- Institut Pasteur, Proteopole &CNRS UMR 3528, F-75015 Paris, France
| | | | - Stéphane Petres
- Institut Pasteur, Proteopole &CNRS UMR 3528, F-75015 Paris, France
| | - Ahmed Haouz
- Institut Pasteur, Proteopole &CNRS UMR 3528, F-75015 Paris, France
| | - Jean-François Hernandez
- Faculté de Pharmacie, Institut des Biomolécules Max Mousseron, UMR5247, CNRS, Universités Montpellier 1 &2, 15 avenue Charles Flahault, 34093 Montpellier cedex 5, France
| | - Odile Mercereau-Puijalon
- 1] Institut Pasteur, Unité d'Immunologie Moléculaires des Parasites, Département de Parasitologie et de Mycologie, F-75015 Paris, France [2] CNRS URA 2581, F-75015 Paris, France
| | - Pedro M Alzari
- 1] Institut Pasteur, Unité de Microbiologie Structurale, Département de Biologie Structurale et Chimie, F-75015 Paris, France [2] CNRS UMR 3528, F-75015 Paris, France [3] Institut Pasteur, Proteopole &CNRS UMR 3528, F-75015 Paris, France
| | - Jean-Christophe Barale
- 1] Institut Pasteur, Unité d'Immunologie Moléculaires des Parasites, Département de Parasitologie et de Mycologie, F-75015 Paris, France [2] CNRS URA 2581, F-75015 Paris, France
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14
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Substrate derived peptidic α-ketoamides as inhibitors of the malarial protease PfSUB1. Bioorg Med Chem Lett 2014; 24:4486-4489. [PMID: 25129616 DOI: 10.1016/j.bmcl.2014.07.086] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2014] [Revised: 07/25/2014] [Accepted: 07/30/2014] [Indexed: 01/19/2023]
Abstract
Peptidic α-ketoamides have been developed as inhibitors of the malarial protease PfSUB1. The design of inhibitors was based on the best known endogenous PfSUB1 substrate sequence, leading to compounds with low micromolar to submicromolar inhibitory activity. SAR studies were performed indicating the requirement of an aspartate mimicking the P1' substituent and optimal P1-P4 length of the non-prime part. The importance of each of the P1-P4 amino acid side chains was investigated, revealing crucial interactions and size limitations.
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15
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Abstract
Despite a century of control and eradication campaigns, malaria remains one of the world's most devastating diseases. Our once-powerful therapeutic weapons are losing the war against the Plasmodium parasite, whose ability to rapidly develop and spread drug resistance hamper past and present malaria-control efforts. Finding new and effective treatments for malaria is now a top global health priority, fuelling an increase in funding and promoting open-source collaborations between researchers and pharmaceutical consortia around the world. The result of this is rapid advances in drug discovery approaches and technologies, with three major methods for antimalarial drug development emerging: (i) chemistry-based, (ii) target-based, and (iii) cell-based. Common to all three of these approaches is the unique ability of structural biology to inform and accelerate drug development. Where possible, SBDD (structure-based drug discovery) is a foundation for antimalarial drug development programmes, and has been invaluable to the development of a number of current pre-clinical and clinical candidates. However, as we expand our understanding of the malarial life cycle and mechanisms of resistance development, SBDD as a field must continue to evolve in order to develop compounds that adhere to the ideal characteristics for novel antimalarial therapeutics and to avoid high attrition rates pre- and post-clinic. In the present review, we aim to examine the contribution that SBDD has made to current antimalarial drug development efforts, covering hit discovery to lead optimization and prevention of parasite resistance. Finally, the potential for structural biology, particularly high-throughput structural genomics programmes, to identify future targets for drug discovery are discussed.
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16
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Suarez C, Volkmann K, Gomes AR, Billker O, Blackman MJ. The malarial serine protease SUB1 plays an essential role in parasite liver stage development. PLoS Pathog 2013; 9:e1003811. [PMID: 24348254 PMCID: PMC3861531 DOI: 10.1371/journal.ppat.1003811] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2013] [Accepted: 10/21/2013] [Indexed: 11/30/2022] Open
Abstract
Transmission of the malaria parasite to its vertebrate host involves an obligatory exoerythrocytic stage in which extensive asexual replication of the parasite takes place in infected hepatocytes. The resulting liver schizont undergoes segmentation to produce thousands of daughter merozoites. These are released to initiate the blood stage life cycle, which causes all the pathology associated with the disease. Whilst elements of liver stage merozoite biology are similar to those in the much better-studied blood stage merozoites, little is known of the molecular players involved in liver stage merozoite production. To facilitate the study of liver stage biology we developed a strategy for the rapid production of complex conditional alleles by recombinase mediated engineering in Escherichia coli, which we used in combination with existing Plasmodium berghei deleter lines expressing Flp recombinase to study subtilisin-like protease 1 (SUB1), a conserved Plasmodium serine protease previously implicated in blood stage merozoite maturation and egress. We demonstrate that SUB1 is not required for the early stages of intrahepatic growth, but is essential for complete development of the liver stage schizont and for production of hepatic merozoites. Our results indicate that inhibitors of SUB1 could be used in prophylactic approaches to control or block the clinically silent pre-erythrocytic stage of the malaria parasite life cycle. Malaria is caused by a single-celled parasite and is transmitted by the bite of an infected mosquito. The inoculated sporozoite forms of the parasite invade liver cells where they replicate, eventually releasing thousands of merozoites into the bloodstream to initiate the blood stage parasite life cycle which causes clinical malaria. The liver stage of the parasite life cycle is asymptomatic, so it is widely considered a potential target for prophylactic vaccine- or drug-based approaches designed to prevent infection. In this study, we use a robust, highly efficient gene engineering approach called recombineering, combined with a conditional gene deletion strategy to examine the function in liver stages of a parasite protease called SUB1, previously implicated in release of blood stage parasites. We show that SUB1 is expressed in the liver stage schizont and that the protease is essential for production of liver stage merozoites. Our results enhance our understanding of malarial liver stage biology, provide new tools for studying essential gene function in malaria, and suggest that inhibitors of SUB1 could be used as prophylactic drugs to prevent clinical malaria.
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Affiliation(s)
- Catherine Suarez
- Division of Parasitology, Medical Research Council National Institute for Medical Research, Mill Hill, London, United Kingdom
| | - Katrin Volkmann
- Wellcome Trust Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - Ana Rita Gomes
- Wellcome Trust Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - Oliver Billker
- Wellcome Trust Sanger Institute, Hinxton, Cambridge, United Kingdom
- * E-mail: (OB); (MJB)
| | - Michael J. Blackman
- Division of Parasitology, Medical Research Council National Institute for Medical Research, Mill Hill, London, United Kingdom
- * E-mail: (OB); (MJB)
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17
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Tawk L, Lacroix C, Gueirard P, Kent R, Gorgette O, Thiberge S, Mercereau-Puijalon O, Ménard R, Barale JC. A key role for Plasmodium subtilisin-like SUB1 protease in egress of malaria parasites from host hepatocytes. J Biol Chem 2013; 288:33336-46. [PMID: 24089525 DOI: 10.1074/jbc.m113.513234] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
In their mammalian host, Plasmodium parasites have two obligatory intracellular development phases, first in hepatocytes and subsequently in erythrocytes. Both involve an orchestrated process of invasion into and egress from host cells. The Plasmodium SUB1 protease plays a dual role at the blood stage by enabling egress of the progeny merozoites from the infected erythrocyte and priming merozoites for subsequent erythrocyte invasion. Here, using conditional mutagenesis in P. berghei, we show that SUB1 plays an essential role at the hepatic stage. Stage-specific sub1 invalidation during prehepatocytic development showed that SUB1-deficient parasites failed to rupture the parasitophorous vacuole membrane and to egress from hepatocytes. Furthermore, mechanically released parasites were not adequately primed and failed to establish a blood stage infection in vivo. The critical involvement of SUB1 in both pre-erythrocytic and erythrocytic developmental phases qualifies SUB1 as an attractive multistage target for prophylactic and therapeutic anti-Plasmodium intervention strategies.
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Affiliation(s)
- Lina Tawk
- From the Institut Pasteur, Unité d'Immunologie Moléculaire des Parasites, Département de Parasitologie et de Mycologie, F-75015 Paris, France
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