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González JEH, Salas-Sarduy E, Alvarez LH, Valiente PA, Arni RK, Pascutti PG. Three Decades of Targeting Falcipains to Develop Antiplasmodial Agents: What have we Learned and What can be Done Next? Curr Med Chem 2024; 31:2234-2263. [PMID: 37711130 DOI: 10.2174/0929867331666230913165219] [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: 03/28/2023] [Revised: 05/06/2023] [Accepted: 07/25/2023] [Indexed: 09/16/2023]
Abstract
Malaria is a devastating infectious disease that affects large swathes of human populations across the planet's tropical regions. It is caused by parasites of the genus Plasmodium, with Plasmodium falciparum being responsible for the most lethal form of the disease. During the intraerythrocytic stage in the human hosts, malaria parasites multiply and degrade hemoglobin (Hb) using a battery of proteases, which include two cysteine proteases, falcipains 2 and 3 (FP-2 and FP-3). Due to their role as major hemoglobinases, FP-2 and FP-3 have been targeted in studies aiming to discover new antimalarials and numerous inhibitors with activity against these enzymes, and parasites in culture have been identified. Nonetheless, cross-inhibition of human cysteine cathepsins remains a serious hurdle to overcome for these compounds to be used clinically. In this article, we have reviewed key functional and structural properties of FP-2/3 and described different compound series reported as inhibitors of these proteases during decades of active research in the field. Special attention is also paid to the wide range of computer-aided drug design (CADD) techniques successfully applied to discover new active compounds. Finally, we provide guidelines that, in our understanding, will help advance the rational discovery of new FP-2/3 inhibitors.
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Affiliation(s)
- Jorge Enrique Hernández González
- Multiuser Center for Biomolecular Innovation, IBILCE/UNESP, São José do Rio Preto, SP, Brazil
- Department of Pharmaceutical Sciences, UZA II, University of Vienna, Vienna, 1090, Austria
| | - Emir Salas-Sarduy
- Instituto de Investigaciones Biotecnológicas Dr. Rodolfo Ugalde, Universidad Nacional de San Martín, CONICET, San Martín, Buenos Aires, Argentina
- Escuela de Bio y Nanotecnología (EByN), Universidad de San Martín (UNSAM), San Martín, Buenos Aires, Argentina
| | | | - Pedro Alberto Valiente
- Donnelly Centre for Cellular & Biomolecular Research, University of Toronto, Toronto, Canada
| | | | - Pedro Geraldo Pascutti
- Laboratório de Modelagem e Dinâmica Molecular, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, RJ, Brazil
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2
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Chakraborty S, Biswas S. Structure-Based Optimization of Protease-Inhibitor Interactions to Enhance Specificity of Human Stefin-A against Falcipain-2 from the Plasmodium falciparum 3D7 Strain. Biochemistry 2023; 62:1053-1069. [PMID: 36763907 DOI: 10.1021/acs.biochem.2c00585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
The emergence of resistance in Plasmodium falciparum to frontline artemisinin-based combination therapies has raised global concerns and emphasized the identification of new drug targets for malaria. Cysteine protease falcipain-2 (FP2), involved in host hemoglobin degradation and instrumental in parasite survival, has long been proposed as a promising malarial drug target. However, designing active-site-targeted small-molecule inhibitors of FP2 becomes challenging due to their off-target specificity toward highly homologous human cysteine cathepsins. The use of proteinaceous inhibitors, which have nonconserved exosite interactions and larger interface area, can effectively circumvent this problem. In this study, we report for the first time that human stefin-A (STFA) efficiently inhibits FP2 with Ki values in the nanomolar range. The FP2-STFA complex crystal structure, determined in this study, and sequence analyses identify a unique nonconserved exosite interaction, compared to human cathepsins. Designing a mutation Lys68 > Arg in STFA amplifies its selectivity garnering a 3.3-fold lower Ki value against FP2, and the crystal structure of the FP2-STFAK68R complex shows stronger electrostatic interaction between side-chains of Arg68 (STFAK68R) and Asp109 (FP2). Comparative structural analyses and molecular dynamics (MD) simulation studies of the complexes further confirm higher buried surface areas, better interaction energies for FP2-STFAK68R, and consistency of the newly developed electrostatic interaction (STFA-R68-FP2-D109) in the MD trajectory. The STFA-K68R mutant also shows higher Ki values against human cathepsin-L and stefin, a step toward eliminating off-target specificity. Hence, this work underlines the design of host-based proteinaceous inhibitors against FP2, with further optimization to render them more potent and selective.
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Affiliation(s)
- Subhoja Chakraborty
- Crystallography and Molecular Biology Division, Saha Institute of Nuclear Physics, HBNI, 1/AF Bidhan Nagar, Kolkata 700064, India.,Homi Bhabha National Institute, Training School Complex, Anushaktinagar, Mumbai 400094, India
| | - Sampa Biswas
- Crystallography and Molecular Biology Division, Saha Institute of Nuclear Physics, HBNI, 1/AF Bidhan Nagar, Kolkata 700064, India.,Homi Bhabha National Institute, Training School Complex, Anushaktinagar, Mumbai 400094, India
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Sarma M, Abdalla M, Zothantluanga JH, Abdullah Thagfan F, Umar AK, Chetia D, Almanaa TN, Al-Shouli ST. Multi-target molecular dynamic simulations reveal glutathione-S-transferase as the most favorable drug target of knipholone in Plasmodium falciparum. J Biomol Struct Dyn 2023; 41:12808-12824. [PMID: 36752355 DOI: 10.1080/07391102.2023.2175378] [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: 10/12/2022] [Accepted: 01/07/2023] [Indexed: 02/09/2023]
Abstract
Knipholone is an antiplasmodial phytocompound obtained from the roots of Kniphofia foliosa. Despite several available studies, the molecular drug targets of knipholone in P. falciparum remained unknown. Nowadays, in silico techniques are widely used to study the molecular interactions between compounds and proteins as they provide results quickly with high precision and accuracy. In this study, we aim to identify the potential molecular drug targets of knipholone in P. falciparum. We selected 10 proteins of P. falciparum with unique metabolic functions and we found that knipholone showed better binding affinity than the native ligands of 6 proteins. Out of the 6 proteins, knipholone showed better enzyme inhibitory potential than the native ligands of 4 proteins. We carried out a 100 ns MD simulations for knipholone and the native ligands of four proteins and this was followed by binding free energy calculations. In each step, the performance of knipholone was compared to the native ligands of the proteins. Knipholone outperformed the native ligand of Glutathione-S-Transferase (1OKT) at crucial computational studies as evidence from the lower protein-ligand root mean square deviation value, protein root mean square fluctuation value, and protein-ligand binding free energies. The ligand properties of knipholone provide additional evidence for its stability and it maintains adequate protein-ligand contacts during the entire simulation. The density functional theory study also supported the stability of knipholone at the active binding site of 1OKT. From the studied proteins, we conclude that Glutathione-S-Transferase is the most favorable drug target for knipholone in P. falciparum.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Malita Sarma
- Department of Pharmaceutical Sciences, Faculty of Science and Engineering, Dibrugarh University, Dibrugarh, Assam, India
| | - Mohnad Abdalla
- Pediatric Research Institute, Children's Hospital Affiliated to Shandong University, Jinan, China
| | - James H Zothantluanga
- Department of Pharmaceutical Sciences, Faculty of Science and Engineering, Dibrugarh University, Dibrugarh, Assam, India
| | - Felwa Abdullah Thagfan
- Department of Biology, College of Science, Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia
| | - Abd Kakhar Umar
- Department of Pharmaceutics and Pharmaceutical Technology, Faculty of Pharmacy, Universitas Padjadjaran, Indonesia
| | - Dipak Chetia
- Department of Pharmaceutical Sciences, Faculty of Science and Engineering, Dibrugarh University, Dibrugarh, Assam, India
| | - Taghreed N Almanaa
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Samia T Al-Shouli
- Immunology Unit, Pathology department, College of Medicine, King Saud University, Riyadh, Saudi Arabia
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Inhibitor of Cysteine Protease of Plasmodium malariae Regulates Malapains, Endogenous Cysteine Proteases of the Parasite. Pathogens 2022; 11:pathogens11050605. [PMID: 35631126 PMCID: PMC9142985 DOI: 10.3390/pathogens11050605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 05/13/2022] [Accepted: 05/16/2022] [Indexed: 02/05/2023] Open
Abstract
Cysteine proteases of malaria parasites have been recognized as potential targets in antimalarial drug development as they play pivotal roles in the biology of these parasites. However, strict regulation of their activities is also necessary to minimize or prevent deleterious damage to the parasite and the host. Previously, we have characterized falcipain family cysteine proteases of Plasmodium malariae, named as malapains (MPs). MPs are active hemoglobinases. They also may participate in the release of merozoites from mature schizonts by facilitating remodeling of erythrocyte skeleton proteins. In this study, we identified and characterized an endogenous inhibitor of cysteine protease of P. malariae (PmICP). PmICP shared similar structural and biochemical properties with ICPs from other Plasmodium species. Recombinant PmICP showed a broad range of inhibitory activities against diverse cysteine proteases such as falcipain family enzymes (MP-2, MP-4, VX-3, VX-4, and FP-3), papain, and human cathepsins B and L, with stronger inhibitory activities against falcipain family enzymes. The inhibitory activity of PmICP was not affected by pH. PmICP was thermo-labile, resulting in rapid loss of its inhibitory activity at a high temperature. PmICP effectively inhibited hemoglobin hydrolysis by MPs and regulated maturation of MPs, suggesting its role as a functional regulator of MPs.
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Roy M, Rawat A, Kaushik S, Jyoti A, Srivastava VK. Endogenous cysteine protease inhibitors in upmost pathogenic parasitic protozoa. Microbiol Res 2022; 261:127061. [DOI: 10.1016/j.micres.2022.127061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 05/04/2022] [Accepted: 05/04/2022] [Indexed: 10/18/2022]
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Tušar L, Usenik A, Turk B, Turk D. Mechanisms Applied by Protein Inhibitors to Inhibit Cysteine Proteases. Int J Mol Sci 2021; 22:ijms22030997. [PMID: 33498210 PMCID: PMC7863939 DOI: 10.3390/ijms22030997] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 01/13/2021] [Accepted: 01/16/2021] [Indexed: 02/07/2023] Open
Abstract
Protein inhibitors of proteases are an important tool of nature to regulate and control proteolysis in living organisms under physiological and pathological conditions. In this review, we analyzed the mechanisms of inhibition of cysteine proteases on the basis of structural information and compiled kinetic data. The gathered structural data indicate that the protein fold is not a major obstacle for the evolution of a protease inhibitor. It appears that nature can convert almost any starting fold into an inhibitor of a protease. In addition, there appears to be no general rule governing the inhibitory mechanism. The structural data make it clear that the “lock and key” mechanism is a historical concept with limited validity. However, the analysis suggests that the shape of the active site cleft of proteases imposes some restraints. When the S1 binding site is shaped as a pocket buried in the structure of protease, inhibitors can apply substrate-like binding mechanisms. In contrast, when the S1 binding site is in part exposed to solvent, the substrate-like inhibition cannot be employed. It appears that all proteases, with the exception of papain-like proteases, belong to the first group of proteases. Finally, we show a number of examples and provide hints on how to engineer protein inhibitors.
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Affiliation(s)
- Livija Tušar
- Department of Biochemistry and Molecular and Structural Biology, Jozef Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia; (L.T.); (A.U.); (B.T.)
- Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins (CIPKeBiP), Jamova cesta 39, 1000 Ljubljana, Slovenia
| | - Aleksandra Usenik
- Department of Biochemistry and Molecular and Structural Biology, Jozef Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia; (L.T.); (A.U.); (B.T.)
- Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins (CIPKeBiP), Jamova cesta 39, 1000 Ljubljana, Slovenia
| | - Boris Turk
- Department of Biochemistry and Molecular and Structural Biology, Jozef Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia; (L.T.); (A.U.); (B.T.)
- Faculty of Chemistry, University of Ljubljana, Večna pot 113, 1000 Ljubljana, Slovenia
- Institute of Regenerative Medicine, I.M. Sechenov First Moscow State Medical University, Bol’shaya Pirogovskaya Ulitsa, 19c1, 119146 Moscow, Russia
| | - Dušan Turk
- Department of Biochemistry and Molecular and Structural Biology, Jozef Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia; (L.T.); (A.U.); (B.T.)
- Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins (CIPKeBiP), Jamova cesta 39, 1000 Ljubljana, Slovenia
- Correspondence: ; Tel.: +386-1477-3857
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Flores-Solis D, Mendoza A, Rentería-González I, Casados-Vazquez LE, Trasviña-Arenas CH, Jiménez-Sandoval P, Benítez-Cardoza CG, Del Río-Portilla F, Brieba LG. Solution structure of the inhibitor of cysteine proteases 1 from Entamoeba histolytica reveals a possible auto regulatory mechanism. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2020; 1868:140512. [PMID: 32731033 DOI: 10.1016/j.bbapap.2020.140512] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 07/07/2020] [Accepted: 07/24/2020] [Indexed: 10/23/2022]
Abstract
The genome of Entamoeba histolytica encodes approximately 50 Cysteine Proteases (CPs) whose activity is regulated by two Inhibitors of Cysteine Proteases (ICPs), EhICP1 and EhICP2. The main difference between both EhICPs is the acquisition of a 17 N-terminal targeting signal in EhICP2 and three exposed cysteine residues in EhICP1. The three exposed cysteines in EhICP1 potentiate the formation of cross-linking species that drive heterogeneity. Here we solved the NMR structure of EhICP1 using a mutant protein without accessible cysteines. Our structural data shows that EhICP1 adopts an immunoglobulin fold composed of seven β-strands, and three solvent exposed loops that resemble the structures of EhICP2 and chagasin. EhICP1 and EhICP2 are able to inhibit the archetypical cysteine protease papain by intercalating their BC loops into the protease active site independently of the character of the residue (serine or threonine) responsible to interact with the active site of papain. EhICP1 and EhICP2 present signals of functional divergence as they clustered in different clades. Two of the three exposed cysteines in EhICP1 are located at the DE loop that intercalates into the CP substrate-binding cleft. We propose that the solvent exposed cysteines of EhICP1 play a role in regulating its inhibitory activity and that in oxidative conditions, the cysteines of EhICP1 react to form intra and intermolecular disulfide bonds that render an inactive inhibitor. EhICP2 is not subject to redox regulation, as this inhibitor does not contain a single cysteine residue. This proposed redox regulation may be related to the differential cellular localization between EhICP1 and EhICP2.
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Affiliation(s)
- David Flores-Solis
- Departamento de Química de Biomacromoléculas, Instituto de Química, Universidad Nacional Autónoma de México, Circuito exterior s/n, Coyoacán, Ciudad de Mexico 04510, Mexico
| | - Angeles Mendoza
- Departamento de Química de Biomacromoléculas, Instituto de Química, Universidad Nacional Autónoma de México, Circuito exterior s/n, Coyoacán, Ciudad de Mexico 04510, Mexico
| | - Itzel Rentería-González
- Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, km. 9.6 Libramiento Norte Carretera Irapuato-León, CP 36821 Irapuato, Guanajuato, Mexico
| | - Luz E Casados-Vazquez
- Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, km. 9.6 Libramiento Norte Carretera Irapuato-León, CP 36821 Irapuato, Guanajuato, Mexico
| | - Carlos H Trasviña-Arenas
- Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, km. 9.6 Libramiento Norte Carretera Irapuato-León, CP 36821 Irapuato, Guanajuato, Mexico
| | - Pedro Jiménez-Sandoval
- Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, km. 9.6 Libramiento Norte Carretera Irapuato-León, CP 36821 Irapuato, Guanajuato, Mexico
| | - Claudia G Benítez-Cardoza
- Laboratorio de Investigación Bioquímica, Programa Institucional en Biomedicina Molecular ENMyH-Instituto Politécnico Nacional, Guillermo Massieu Helguera No. 239, La Escalera Ticoman, 07320, D.F, Mexico
| | - Federico Del Río-Portilla
- Departamento de Química de Biomacromoléculas, Instituto de Química, Universidad Nacional Autónoma de México, Circuito exterior s/n, Coyoacán, Ciudad de Mexico 04510, Mexico.
| | - Luis G Brieba
- Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, km. 9.6 Libramiento Norte Carretera Irapuato-León, CP 36821 Irapuato, Guanajuato, Mexico.
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8
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Zhu L, Shan L, Zhu J, Li L, Li S, Wang L, Wang J, Zhang S, Zhou H, Zhang W, Li H. Discovery of a natural fluorescent probe targeting the Plasmodium falciparum cysteine protease falcipain-2. SCIENCE CHINA. LIFE SCIENCES 2020; 63:1016-1025. [PMID: 32048162 DOI: 10.1007/s11427-019-1581-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 11/26/2019] [Indexed: 01/19/2023]
Abstract
The Plasmodium falciparum cysteine protease falcipain-2 (FP-2) is an attractive antimalarial target. Here, we discovered that the natural compound NP1024 is a nonpeptidic inhibitor of FP-2 with an IC50 value of 0.44 μmol L-1. The most exciting finding is that both in vitro and in vivo, NP1024 directly targets FP-2 in malaria parasite-infected erythrocytes as a natural fluorescent probe, thereby paving the way for an integration of malaria diagnosis and treatment.
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Affiliation(s)
- Lili Zhu
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, 200237, China
| | - Lei Shan
- Department of Natural Product Chemistry, School of Pharmacy, Second Military Medical University, Shanghai, 200433, China
| | - Junsheng Zhu
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, 200237, China
| | - Li Li
- Department of Natural Product Chemistry, School of Pharmacy, Second Military Medical University, Shanghai, 200433, China
| | - Shiliang Li
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, 200237, China
| | - Liyan Wang
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, 200237, China
| | - Jiawei Wang
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, 200237, China
| | - Shoude Zhang
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, 200237, China
- Department of Natural Product Chemistry, School of Pharmacy, Second Military Medical University, Shanghai, 200433, China
| | - Hongchang Zhou
- School of Medicine, Huzhou University, Huzhou Central Hospital, Huzhou, 313000, China
| | - Weidong Zhang
- Department of Natural Product Chemistry, School of Pharmacy, Second Military Medical University, Shanghai, 200433, China.
| | - Honglin Li
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, 200237, China.
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9
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Machin JM, Kantsadi AL, Vakonakis I. The complex of Plasmodium falciparum falcipain-2 protease with an (E)-chalcone-based inhibitor highlights a novel, small, molecule-binding site. Malar J 2019; 18:388. [PMID: 31791339 PMCID: PMC6889325 DOI: 10.1186/s12936-019-3043-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2019] [Accepted: 11/27/2019] [Indexed: 12/03/2022] Open
Abstract
Background Malaria kills over 400,000 people each year and nearly half the world’s population live in at-risk areas. Progress against malaria has recently stalled, highlighting the need for developing novel therapeutics. The parasite haemoglobin degradation pathway, active in the blood stage of the disease where malaria symptoms and lethality manifest, is a well-established drug target. A key enzyme in this pathway is the papain-type protease falcipain-2. Methods The crystallographic structure of falcipain-2 at 3.45 Å resolution was resolved in complex with an (E)-chalcone small-molecule inhibitor. The falcipain-2–(E)-chalcone complex was analysed with reference to previous falcipain complexes and their similarity to human cathepsin proteases. Results The (E)-chalcone inhibitor binds falcipain-2 to the rear of the substrate-binding cleft. This is the first structure of a falcipain protease where the rear of the substrate cleft is bound by a small molecule. In this manner, the (E)-chalcone inhibitor mimics interactions observed in protein-based falcipain inhibitors, which can achieve high interaction specificity. Conclusions This work informs the search for novel anti-malaria therapeutics that target falcipain-2 by showing the binding site and interactions of the medically privileged (E)-chalcone molecule. Furthermore, this study highlights the possibility of chemically combining the (E)-chalcone molecule with an existing active-site inhibitor of falcipain, which may yield a potent and selective compound for blocking haemoglobin degradation by the malaria parasite.
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Affiliation(s)
- Jonathan M Machin
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
| | - Anastassia L Kantsadi
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
| | - Ioannis Vakonakis
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK.
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10
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Liu J, Svärd SG, Klotz C. Giardia intestinalis cystatin is a potent inhibitor of papain, parasite cysteine proteases and, to a lesser extent, human cathepsin B. FEBS Lett 2019; 593:1313-1325. [PMID: 31077354 DOI: 10.1002/1873-3468.13433] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 04/16/2019] [Accepted: 05/04/2019] [Indexed: 11/09/2022]
Abstract
Cystatins are important regulators of papain-like cysteine proteases. In the protozoan parasite Giardia intestinalis, papain-like cysteine proteases play an essential role in the parasite's biology and pathogenicity. Here, we characterized a cysteine protease inhibitor of G. intestinalis that belongs to type-I-cystatins. The parasite cystatin is shown to be a strong inhibitor of papain (Ki ≈ 0.3 nm) and three parasite cysteine proteases (CP14019, CP16160 and CP16779, Ki ≈ 0.9-5.8 nm), but a weaker inhibitor of human cathepsin B (Ki ≈ 79.9 nm). The protein localizes mainly in the cytoplasm. Together, these data suggest that cystatin of G. intestinalis plays a role in the regulation of cysteine protease activities in the parasite and, possibly, in the interaction with the host.
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Affiliation(s)
- Jingyi Liu
- Department of Cell and Molecular Biology, BMC, Uppsala University, Sweden
| | - Staffan G Svärd
- Department of Cell and Molecular Biology, BMC, Uppsala University, Sweden
| | - Christian Klotz
- Department of Mycotic and Parasitic Agents and Mycobacteria (FG16), Robert Koch-Institute, Berlin, Germany
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11
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Crucial residues in falcipains that mediate hemoglobin hydrolysis. Exp Parasitol 2019; 197:43-50. [PMID: 30648557 DOI: 10.1016/j.exppara.2019.01.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 11/03/2018] [Accepted: 01/11/2019] [Indexed: 02/08/2023]
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12
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Synthetic microbial consortia enable rapid assembly of pure translation machinery. Nat Chem Biol 2017; 14:29-35. [DOI: 10.1038/nchembio.2514] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 10/04/2017] [Indexed: 12/23/2022]
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13
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Ogungbe IV, Setzer WN. The Potential of Secondary Metabolites from Plants as Drugs or Leads against Protozoan Neglected Diseases-Part III: In-Silico Molecular Docking Investigations. Molecules 2016; 21:E1389. [PMID: 27775577 PMCID: PMC6274513 DOI: 10.3390/molecules21101389] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 10/06/2016] [Accepted: 10/12/2016] [Indexed: 12/11/2022] Open
Abstract
Malaria, leishmaniasis, Chagas disease, and human African trypanosomiasis continue to cause considerable suffering and death in developing countries. Current treatment options for these parasitic protozoal diseases generally have severe side effects, may be ineffective or unavailable, and resistance is emerging. There is a constant need to discover new chemotherapeutic agents for these parasitic infections, and natural products continue to serve as a potential source. This review presents molecular docking studies of potential phytochemicals that target key protein targets in Leishmania spp., Trypanosoma spp., and Plasmodium spp.
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Affiliation(s)
- Ifedayo Victor Ogungbe
- Department of Chemistry and Biochemistry, Jackson State University, Jackson, MS 39217, USA.
| | - William N Setzer
- Department of Chemistry, University of Alabama in Huntsville, Huntsville, AL 35899, USA.
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14
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Costa TF, Lima APC. Natural cysteine protease inhibitors in protozoa: Fifteen years of the chagasin family. Biochimie 2016; 122:197-207. [DOI: 10.1016/j.biochi.2015.11.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 11/02/2015] [Indexed: 12/19/2022]
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15
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Identification of novel class of falcipain-2 inhibitors as potential antimalarial agents. Bioorg Med Chem 2015; 23:2221-40. [DOI: 10.1016/j.bmc.2015.02.062] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 02/16/2015] [Accepted: 02/26/2015] [Indexed: 11/18/2022]
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Persch E, Dumele O, Diederich F. Molekulare Erkennung in chemischen und biologischen Systemen. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201408487] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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17
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Persch E, Dumele O, Diederich F. Molecular recognition in chemical and biological systems. Angew Chem Int Ed Engl 2015; 54:3290-327. [PMID: 25630692 DOI: 10.1002/anie.201408487] [Citation(s) in RCA: 417] [Impact Index Per Article: 46.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Indexed: 12/13/2022]
Abstract
Structure-based ligand design in medicinal chemistry and crop protection relies on the identification and quantification of weak noncovalent interactions and understanding the role of water. Small-molecule and protein structural database searches are important tools to retrieve existing knowledge. Thermodynamic profiling, combined with X-ray structural and computational studies, is the key to elucidate the energetics of the replacement of water by ligands. Biological receptor sites vary greatly in shape, conformational dynamics, and polarity, and require different ligand-design strategies, as shown for various case studies. Interactions between dipoles have become a central theme of molecular recognition. Orthogonal interactions, halogen bonding, and amide⋅⋅⋅π stacking provide new tools for innovative lead optimization. The combination of synthetic models and biological complexation studies is required to gather reliable information on weak noncovalent interactions and the role of water.
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Affiliation(s)
- Elke Persch
- Laboratorium für Organische Chemie, Departement Chemie und Angewandte Biowissenschaften, ETH Zürich, Vladimir-Prelog-Weg 3, 8093 Zürich (Switzerland)
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18
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Lehmann C, Heitmann A, Mishra S, Burda PC, Singer M, Prado M, Niklaus L, Lacroix C, Ménard R, Frischknecht F, Stanway R, Sinnis P, Heussler V. A cysteine protease inhibitor of plasmodium berghei is essential for exo-erythrocytic development. PLoS Pathog 2014; 10:e1004336. [PMID: 25166051 PMCID: PMC4148452 DOI: 10.1371/journal.ppat.1004336] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2013] [Accepted: 07/08/2014] [Indexed: 11/18/2022] Open
Abstract
Plasmodium parasites express a potent inhibitor of cysteine proteases (ICP) throughout their life cycle. To analyze the role of ICP in different life cycle stages, we generated a stage-specific knockout of the Plasmodium berghei ICP (PbICP). Excision of the pbicb gene occurred in infective sporozoites and resulted in impaired sporozoite invasion of hepatocytes, despite residual PbICP protein being detectable in sporozoites. The vast majority of these parasites invading a cultured hepatocyte cell line did not develop to mature liver stages, but the few that successfully developed hepatic merozoites were able to initiate a blood stage infection in mice. These blood stage parasites, now completely lacking PbICP, exhibited an attenuated phenotype but were able to infect mosquitoes and develop to the oocyst stage. However, PbICP-negative sporozoites liberated from oocysts exhibited defective motility and invaded mosquito salivary glands in low numbers. They were also unable to invade hepatocytes, confirming that control of cysteine protease activity is of critical importance for sporozoites. Importantly, transfection of PbICP-knockout parasites with a pbicp-gfp construct fully reversed these defects. Taken together, in P. berghei this inhibitor of the ICP family is essential for sporozoite motility but also appears to play a role during parasite development in hepatocytes and erythrocytes.
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Affiliation(s)
| | - Anna Heitmann
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Satish Mishra
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | | | - Mirko Singer
- University of Heidelberg Medical School, Heidelberg, Germany
| | - Monica Prado
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Livia Niklaus
- Institute of Cell Biology, University of Bern, Bern, Switzerland
| | - Céline Lacroix
- Institute Pasteur, Unité de Biologie et Génétique du Paludisme, Paris, France
| | - Robert Ménard
- Institute Pasteur, Unité de Biologie et Génétique du Paludisme, Paris, France
| | | | - Rebecca Stanway
- Institute of Cell Biology, University of Bern, Bern, Switzerland
| | - Photini Sinnis
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Volker Heussler
- Institute of Cell Biology, University of Bern, Bern, Switzerland
- * E-mail:
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19
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Omotuyi OI. Methyl-methoxylpyrrolinone and flavinium nucleus binding signatures on falcipain-2 active site. J Mol Model 2014; 20:2386. [PMID: 25096811 DOI: 10.1007/s00894-014-2386-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 07/17/2014] [Indexed: 01/18/2023]
Abstract
Following the increasing reports of human toxicity and plasmodium resistance to artemisinin and its derivatives, falcipain-2 (FP-2) is now emerging as the choice antimalarial drug target. Coincidentally, FP-2 is the in vivo target of naturally occurring, therapeutically safe flavonoids (stenopalustroside, myricetin, and fisetin) and symplostatin (symplostatin 4) compounds known to exhibit potent in vitro and in vivo antiplasmodial actions. Here, the structural bases for their inhibitory actions have been studied using molecular dynamics simulation. Myricetin and fisetin act as proton transfer tunnel breakers by inserting between His174 and Cys42, which are key active site residues of FP-2, stenopalustroside inhibits the polarization of His174 by Asn173; a major preparatory step for Cys42/His174 proton transfer process. The roles of flavonoids are favored by T-shaped pi-pi interactions with His174. Symplostatin 4 inserts its methyl-methoxylpyrrolinone moiety into the active site where its proton acceptor function prepares Cys42 for nucleophilic attack on the Michael α,β-unsaturated bonds on its 4(S)-amino-2(E)-pentenoate moiety. Further analyses of the structures identified a unique bridge formed on FP-2 active site groove by stenopalustroside and symplostatin 4 during interaction with the sub-site I of FP-2, whereas fisetin preferentially interacts with sub-site II and myricetin interacts with sub-site III residues. Ultimately, symplostatin-4, myricetin, and fisetin were better than stenopalustroside at trapping FP-2 in its inactive state as revealed by comparative RSMD plots with X-ray structures of FP-2 co-crystallized with inhibitors. Comparative estimates of free energy of binding using the Molecular Mechanics-Poisson Boltzmann Surface Area (MMPBSA) method suggested that His174 protonation may further enhance stenopalustroside-FP-2 interaction. The unique binding signatures of the ligands within the FP-2 active site groove and its sub-sites may explain the subtle differences in their IC50 values and their mechanism of inhibition.
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Affiliation(s)
- Olaposi I Omotuyi
- Center for Drug Discovery and Therapeutic Innovation, Nagasaki University, Nagasaki, Japan,
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20
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Omotuyi IO, Hamada T. Dynamical footprint of falcipain-2 catalytic triad in hemoglobin-β-bound state. J Biomol Struct Dyn 2014; 33:1027-36. [PMID: 24943200 DOI: 10.1080/07391102.2014.924878] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Falcipain-2 (FP-2) is a member of papain family of cysteine proteases and the major hemoglobinase of the hemoglobin detoxification and hemozoin polymerization complex localized in the food vacuole of the plasmodium species. FP-2 is currently gaining clinical significance as the drug target of choice in combating malaria epidemic. Here, a theoretical FP-2/hemoglobin complex has been proposed and the dynamical footprint and energetics of binding have been investigated using molecular and quantum mechanics approaches. The mapped interaction interface comprises residues 34-51 of hemoglobin and cysteine-42/histidine-174/glutamine-36/asparagine-173/204 and subsites S1, S1', and S3 of FP-2. In hemoglobin-bound FP-2, asparagine-173 preferentially partners histidine-174, while glutamine-36 is preferred in ligand-free state. Cysteine-42 exhibits dihedral switch from 110° to 30° in free and bound states, respectively, with exclusion of water from the binding core upon hemoglobin binding. Hemoglobin similarly exhibits high occupancy within .2 nm distance with charged amido acid-rich subsites S1 and S3 of FP-2 functioning in tandem to reduce conformational flexibility of hemoglobin and facilitate the formation of a stabilizing anti-parallel β-sheet between Leucine-172-valine-176 of FP-2 and phenylalanine-45-asparate-47 of hemoglobin and to overcome the + 1.13e + 5 eV activation energy required to optimize the FP-2/hemoglobin-β conformation that precedes hydrolysis.
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Affiliation(s)
- I O Omotuyi
- a Department of Molecular Pharmacology and Neuroscience , Nagasaki University , Nagasaki , Japan
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21
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Arafet K, Ferrer S, Martí S, Moliner V. Quantum mechanics/molecular mechanics studies of the mechanism of falcipain-2 inhibition by the epoxysuccinate E64. Biochemistry 2014; 53:3336-46. [PMID: 24811524 DOI: 10.1021/bi500060h] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Because of the increasing resistance of malaria parasites to antimalarial drugs, the lack of highly effective vaccines, and an inadequate control of mosquito vectors, the problem is growing, especially in the developing world. New approaches to drug development are consequently required. One of the proteases involved in the degradation of human hemoglobin is named falcipain-2 (FP2), which has emerged as a promising target for the development of novel antimalarial drugs. However, very little is known about the inhibition of FP2. In this paper, the inhibition of FP2 by the epoxysuccinate E64 has been studied by molecular dynamics (MD) simulations using hybrid AM1d/MM and M06-2X/MM potentials to obtain a complete picture of the possible free energy reaction paths. A thorough analysis of the reaction mechanism has been conducted to understand the inhibition of FP2 by E64. According to our results, the irreversible attack of Cys42 on E64 can take place on both carbon atoms of the epoxy ring because both processes present similar barriers. While the attack on the C2 atom presents a slightly smaller barrier (12.3 vs 13.6 kcal mol(-1)), the inhibitor-protein complex derived from the attack on C3 appears to be much more stabilized. In contrast to previous hypotheses, our results suggest that residues such as Gln171, Asp170, Gln36, Trp43, Asn81, and even His174 would be anchoring the inhibitor in a proper orientation for the reaction to take place. These results may be useful for the rational design of new compounds with higher inhibitory activity.
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Affiliation(s)
- Kemel Arafet
- Departament de Química Física i Analítica, Universitat Jaume I , 12071 Castelló, Spain
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22
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Structural basis for the immunomodulatory function of cysteine protease inhibitor from human roundworm Ascaris lumbricoides. PLoS One 2014; 9:e96069. [PMID: 24781326 PMCID: PMC4004552 DOI: 10.1371/journal.pone.0096069] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Accepted: 04/03/2014] [Indexed: 11/19/2022] Open
Abstract
Immunosuppression associated with infections of nematode parasites has been documented. Cysteine protease inhibitor (CPI) released by the nematode parasites is identified as one of the major modulators of host immune response. In this report, we demonstrated that the recombinant CPI protein of Ascaris lumbricoides (Al-CPI) strongly inhibited the activities of cathepsin L, C, S, and showed weaker effect to cathepsin B. Crystal structure of Al-CPI was determined to 2.1 Å resolution. Two segments of Al-CPI, loop 1 and loop 2, were proposed as the key structure motifs responsible for Al-CPI binding with proteases and its inhibitory activity. Mutations at loop 1 and loop 2 abrogated the protease inhibition activity to various extents. These results provide the molecular insight into the interaction between the nematode parasite and its host and will facilitate the development of anthelmintic agents or design of anti-autoimmune disease drugs.
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23
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Cross-talk between malarial cysteine proteases and falstatin: the BC loop as a hot-spot target. PLoS One 2014; 9:e93008. [PMID: 24699522 PMCID: PMC3974720 DOI: 10.1371/journal.pone.0093008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 02/27/2014] [Indexed: 02/05/2023] Open
Abstract
Cysteine proteases play a crucial role in the development of the human malaria parasites Plasmodium falciparum and Plasmodium vivax. Our earlier studies demonstrated that these enzymes are equipped with specific domains for defined functions and further suggested the mechanism of activation of cysteine proteases. The activities of these proteases are regulated by a new class of endogenous inhibitors of cysteine proteases (ICPs). Structural studies of the ICPs of Trypanosoma cruzi (chagasin) and Plasmodium berghei (PbICP) indicated that three loops (termed BC, DE, and FG) are crucial for binding to target proteases. Falstatin, an ICP of P. falciparum, appears to play a crucial role in invasion of erythrocytes and hepatocytes. However, the mechanism of inhibition of cysteine proteases by falstatin has not been established. Our study suggests that falstatin is the first known ICP to function as a multimeric protein. Using site-directed mutagenesis, hemoglobin hydrolysis assays and peptide inhibition studies, we demonstrate that the BC loop, but not the DE or FG loops, inhibits cysteine proteases of P. falciparum and P. vivax via hydrogen bonds. These results suggest that the BC loop of falstatin acts as a hot-spot target for inhibiting malarial cysteine proteases. This finding suggests new strategies for the development of anti-malarial agents based on protease-inhibitor interactions.
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24
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Pei Y, Miller JL, Lindner SE, Vaughan AM, Torii M, Kappe SHI. Plasmodium yoelii inhibitor of cysteine proteases is exported to exomembrane structures and interacts with yoelipain-2 during asexual blood-stage development. Cell Microbiol 2013; 15:1508-1526. [PMID: 23421981 DOI: 10.1111/cmi.12124] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Revised: 02/06/2013] [Accepted: 02/07/2013] [Indexed: 11/28/2022]
Abstract
Plasmodium falciparum (Pf) blood stages express falstatin, an inhibitor of cysteine proteases (ICP), which is implicated in regulating proteolysis during red blood cell infection. Recent data using the Plasmodium berghei rodent malaria model suggested an additional role for ICP in the infection of hepatocytes by sporozoites and during liver-stage development. Here we further characterize the role of ICP in vivo during infection with Plasmodium yoelii (Py) and Pf. We found that Py-ICP was refractory to targeted gene deletion indicating an essential function during asexual blood-stage replication, but significant downregulation of ICP using a regulated system did not impact blood-stage growth. Py-ICP localized to vesicles within the asexual blood-stage parasite cytoplasm, as well as the parasitophorous vacuole, and was exported to dynamic exomembrane structures in the infected RBC. In sporozoites, expression was observed in rhoptries, in addition to intracellular vesicles distinct from TRAP containing micronemes. During liver-stage development, Py-ICP was confined to the parasite compartment until the final phase of liver-stage development when, after parasitophorous vacuolemembrane breakdown, it was released into the infected hepatocyte. Finally, we identified the cysteine protease yoelipain-2 as a binding partner of Py-ICP during blood-stage infection. These data show that ICP may be important in regulating proteolytic processes during blood-stage development, and is likely playing a role in liver stage-hepatocyte interactions at the time of exoerythrocytic merozoite release.
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Affiliation(s)
- Ying Pei
- Seattle Biomedical Research Institute, 307 Westlake Avenue North, Suite 500, Seattle, WA 98109, USA
| | - Jessica L Miller
- Seattle Biomedical Research Institute, 307 Westlake Avenue North, Suite 500, Seattle, WA 98109, USA
| | - Scott E Lindner
- Seattle Biomedical Research Institute, 307 Westlake Avenue North, Suite 500, Seattle, WA 98109, USA
| | - Ashley M Vaughan
- Seattle Biomedical Research Institute, 307 Westlake Avenue North, Suite 500, Seattle, WA 98109, USA
| | - Motomi Torii
- Department of Molecular Parasitology, Ehime University Graduate School of Medicine, Toon, Ehime 791-0295, Japan
| | - Stefan H I Kappe
- Seattle Biomedical Research Institute, 307 Westlake Avenue North, Suite 500, Seattle, WA 98109, USA.,Department of Global Health, University of Washington, Seattle, WA, 98195, USA
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25
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Pandey KC. Macromolecular inhibitors of malarial cysteine proteases —An invited review. ACTA ACUST UNITED AC 2013. [DOI: 10.4236/jbise.2013.69108] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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26
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Guédez G, Hipp K, Windeisen V, Derrer B, Gengenbacher M, Böttcher B, Sinning I, Kappes B, Tews I. Assembly of the eukaryotic PLP-synthase complex from Plasmodium and activation of the Pdx1 enzyme. Structure 2012; 20:172-84. [PMID: 22244765 DOI: 10.1016/j.str.2011.11.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Revised: 11/04/2011] [Accepted: 11/05/2011] [Indexed: 11/26/2022]
Abstract
Biosynthesis of vitamins is fundamental to malaria parasites. Plasmodia synthesize the active form of vitamin B(6) (pyridoxal 5'-phosphate, PLP) using a PLP synthase complex. The EM analysis shown here reveals a random association pattern of up to 12 Pdx2 glutaminase subunits to the dodecameric Pdx1 core complex. Interestingly, Plasmodium falciparum PLP synthase organizes in fibers. The crystal structure shows differences in complex formation to bacterial orthologs as interface variations. Alternative positioning of an α helix distinguishes an open conformation from a closed state when the enzyme binds substrate. The pentose substrate is covalently attached through its C1 and forms a Schiff base with Lys84. Ammonia transfer between Pdx2 glutaminase and Pdx1 active sites is regulated by a transient tunnel. The mutagenesis analysis allows defining the requirement for conservation of critical methionines, whereas there is also plasticity in ammonia tunnel construction as seen from comparison across different species.
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Affiliation(s)
- Gabriela Guédez
- Heidelberg University Biochemistry Center (BZH), Im Neuenheimer Feld 328, 69120 Heidelberg, Germany
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27
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Jaskolski M. A new piece in the 3D Jigsaw of malaria parasite. Structure 2011; 19:901-2. [PMID: 21742255 DOI: 10.1016/j.str.2011.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The structural insights presented by Hansen et al. in this issue of Structure on how a key malaria parasite protease is blocked by its inhibitor may provide a flicker of hope in the desperate struggle to develop drugs against one of the most severe health problems.
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Affiliation(s)
- Mariusz Jaskolski
- Department of Crystallography, Faculty of Chemistry, A. Mickiewicz University and Center for Biocrystallographic Research, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, Poland.
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Hansen G, Schwarzloh B, Rennenberg A, Heussler VT, Hilgenfeld R. The macromolecular complex of ICP and falcipain-2 from Plasmodium: preparation, crystallization and preliminary X-ray diffraction analysis. Acta Crystallogr Sect F Struct Biol Cryst Commun 2011; 67:1406-10. [PMID: 22102243 DOI: 10.1107/s1744309111034592] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2011] [Accepted: 08/22/2011] [Indexed: 11/10/2022]
Abstract
The malaria parasite Plasmodium depends on the tight control of cysteine-protease activity throughout its life cycle. Recently, the characterization of a new class of potent inhibitors of cysteine proteases (ICPs) secreted by Plasmodium has been reported. Here, the recombinant production, purification and crystallization of the inhibitory C-terminal domain of ICP from P. berghei in complex with the P. falciparum haemoglobinase falcipain-2 is described. The 1:1 complex was crystallized in space group P4(3), with unit-cell parameters a = b = 71.15, c = 120.09 Å. A complete diffraction data set was collected to a resolution of 2.6 Å.
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Affiliation(s)
- Guido Hansen
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, Ratzeburger Allee 160, 23538 Lübeck, Germany
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