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Affiliation(s)
- Luděk Kořený
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
- * E-mail: (LK); (JL)
| | - Miroslav Oborník
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
- Faculty of Science, University of South Bohemia, České Budějovice (Budweis), Czech Republic
- Institute of Microbiology, Czech Academy of Sciences, Třeboň, Czech Republic
| | - Julius Lukeš
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
- Faculty of Science, University of South Bohemia, České Budějovice (Budweis), Czech Republic
- * E-mail: (LK); (JL)
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Guttery DS, Ferguson DJP, Poulin B, Xu Z, Straschil U, Klop O, Solyakov L, Sandrini SM, Brady D, Nieduszynski CA, Janse CJ, Holder AA, Tobin AB, Tewari R. A putative homologue of CDC20/CDH1 in the malaria parasite is essential for male gamete development. PLoS Pathog 2012; 8:e1002554. [PMID: 22383885 PMCID: PMC3285604 DOI: 10.1371/journal.ppat.1002554] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Accepted: 01/12/2012] [Indexed: 11/19/2022] Open
Abstract
Cell-cycle progression is governed by a series of essential regulatory proteins. Two major regulators are cell-division cycle protein 20 (CDC20) and its homologue, CDC20 homologue 1 (CDH1), which activate the anaphase-promoting complex/cyclosome (APC/C) in mitosis, and facilitate degradation of mitotic APC/C substrates. The malaria parasite, Plasmodium, is a haploid organism which, during its life-cycle undergoes two stages of mitosis; one associated with asexual multiplication and the other with male gametogenesis. Cell-cycle regulation and DNA replication in Plasmodium was recently shown to be dependent on the activity of a number of protein kinases. However, the function of cell division cycle proteins that are also involved in this process, such as CDC20 and CDH1 is totally unknown. Here we examine the role of a putative CDC20/CDH1 in the rodent malaria Plasmodium berghei (Pb) using reverse genetics. Phylogenetic analysis identified a single putative Plasmodium CDC20/CDH1 homologue (termed CDC20 for simplicity) suggesting that Plasmodium APC/C has only one regulator. In our genetic approach to delete the endogenous cdc20 gene of P. berghei, we demonstrate that PbCDC20 plays a vital role in male gametogenesis, but is not essential for mitosis in the asexual blood stage. Furthermore, qRT-PCR analysis in parasite lines with deletions of two kinase genes involved in male sexual development (map2 and cdpk4), showed a significant increase in cdc20 transcription in activated gametocytes. DNA replication and ultra structural analyses of cdc20 and map2 mutants showed similar blockage of nuclear division at the nuclear spindle/kinetochore stage. CDC20 was phosphorylated in asexual and sexual stages, but the level of modification was higher in activated gametocytes and ookinetes. Changes in global protein phosphorylation patterns in the Δcdc20 mutant parasites were largely different from those observed in the Δmap2 mutant. This suggests that CDC20 and MAP2 are both likely to play independent but vital roles in male gametogenesis.
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Affiliation(s)
- David S. Guttery
- Centre for Genetics and Genomics, School of Biology Queens Medical Centre, University of Nottingham, Nottingham, United Kingdom
| | - David J. P. Ferguson
- Nuffield Department of Clinical Laboratory Science, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Benoit Poulin
- Centre for Genetics and Genomics, School of Biology Queens Medical Centre, University of Nottingham, Nottingham, United Kingdom
| | - Zhengyao Xu
- Centre for Genetics and Genomics, School of Biology Queens Medical Centre, University of Nottingham, Nottingham, United Kingdom
| | - Ursula Straschil
- Division of Cell and Molecular Biology, Imperial College London, London, United Kingdom
| | - Onny Klop
- Leiden Malaria Research Group, Department of Parasitology, Leiden University Medical, Leiden, The Netherlands
| | - Lev Solyakov
- Department of Cell Physiology and Pharmacology, College of Medicine, Biological Sciences and Psychology, University of Leicester, Leicester, United Kingdom
| | - Sara M. Sandrini
- Centre for Genetics and Genomics, School of Biology Queens Medical Centre, University of Nottingham, Nottingham, United Kingdom
| | - Declan Brady
- Centre for Genetics and Genomics, School of Biology Queens Medical Centre, University of Nottingham, Nottingham, United Kingdom
| | - Conrad A. Nieduszynski
- Centre for Genetics and Genomics, School of Biology Queens Medical Centre, University of Nottingham, Nottingham, United Kingdom
| | - Chris J. Janse
- Leiden Malaria Research Group, Department of Parasitology, Leiden University Medical, Leiden, The Netherlands
| | - Anthony A. Holder
- Division of Parasitology, MRC National Institute for Medical Research, London, United Kingdom
| | - Andrew B. Tobin
- Department of Cell Physiology and Pharmacology, College of Medicine, Biological Sciences and Psychology, University of Leicester, Leicester, United Kingdom
| | - Rita Tewari
- Centre for Genetics and Genomics, School of Biology Queens Medical Centre, University of Nottingham, Nottingham, United Kingdom
- Division of Cell and Molecular Biology, Imperial College London, London, United Kingdom
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Johann L, Lanfranchi DA, Davioud-Charvet E, Elhabiri M. A physico-biochemical study on potential redox-cyclers as antimalarial and anti-schistosomal drugs. Curr Pharm Des 2012; 18:3539-66. [PMID: 22607146 PMCID: PMC3711147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Accepted: 03/12/2012] [Indexed: 05/31/2023]
Abstract
The role of redox enzymes in establishing a microenvironment for parasite development is well characterized. Mimicking human glucose-6-phosphate dehydrogenase and glutathione reductase (GR) deficiencies by redox-cycling compounds thus represents a challenge to the design of new preclinical antiparasitic drug candidates. Schistosomes and malarial parasites feed on hemoglobin. Heme, the toxic prosthetic group of the protein, is not digested and represents a challenge to the redox metabolism of the parasites. Here, we report on old and new redox-cycling compounds--whose antiparasitic activities are related to their interference with (met)hemoglobin degradation and hematin crystallization. Three key-assays allowed probing and differentiating the mechanisms of drug actions. Inhibition of β-hematin was first compared to the heme binding as a possible mode of action. All tested ligands interact with the hematin π-π dimer with K(D) similar to those measured for the major antiparasitic drugs. No correlation between a high affinity for hematin and the capacity to prevent β-hematin formation was however deduced. Inhibition of β-hematin formation is consequently not the result of a single process but results from redox processes following electron transfers from the drugs to iron(III)-containing targets. The third experiment highlighted that several redox-active compounds (in their reduced forms) are able to efficiently reduce methemoglobin to hemoglobin in a GR/NADPH-coupled assay. A correlation between methemoglobin reduction and inhibition of β-hematin was shown, demonstrating that both processes are closely related. The ability of our redox-cyclers to trigger methemoglobin reduction therefore constitutes a critical step to understand the mechanism of action of our drug candidates.
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Affiliation(s)
- Laure Johann
- Laboratoire de Chimie Bioorganique et Médicinale, European School of Chemistry, Polymers and Materials (ECPM), University of Strasbourg and Centre National de la Recherche Scientifique, UMR 7509, 25, rue Becquerel, F-67087 Strasbourg, France
| | - Don Antoine Lanfranchi
- Laboratoire de Chimie Bioorganique et Médicinale, European School of Chemistry, Polymers and Materials (ECPM), University of Strasbourg and Centre National de la Recherche Scientifique, UMR 7509, 25, rue Becquerel, F-67087 Strasbourg, France
| | - Elisabeth Davioud-Charvet
- Laboratoire de Chimie Bioorganique et Médicinale, European School of Chemistry, Polymers and Materials (ECPM), University of Strasbourg and Centre National de la Recherche Scientifique, UMR 7509, 25, rue Becquerel, F-67087 Strasbourg, France
| | - Mourad Elhabiri
- Laboratoire de Chimie Bioorganique et Médicinale, European School of Chemistry, Polymers and Materials (ECPM), University of Strasbourg and Centre National de la Recherche Scientifique, UMR 7509, 25, rue Becquerel, F-67087 Strasbourg, France
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Li T, Yowell CA, Beyer BB, Hung SH, Westling J, Lam MT, Dunn BM, Dame JB. Recombinant expression and enzymatic subsite characterization of plasmepsin 4 from the four Plasmodium species infecting man. Mol Biochem Parasitol 2005; 135:101-9. [PMID: 15287591 DOI: 10.1016/j.molbiopara.2004.01.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Plasmepsin 4 from Plasmodium falciparum and orthologs from Plasmodium malariae, Plasmodium ovale and Plasmodium vivax have been expressed in recombinant form, and properties of the active site of each enzyme characterized by kinetic analysis. A panel of chromogenic peptide substrates systematically substituted at the P3, P2, P2' and P3' positions was used to estimate enzyme/ligand interactions in the corresponding enzyme subsites based upon kinetic data. The kinetic parameters kcat, Km and kcat/Km were measured to identify optimal substrates for each enzyme and also sequences that were readily cleaved by the plasmepsins but poorly by host aspartic peptidases. Computer generated models were utilized to compare enzyme structures and interpret kinetic results. The orthologous plasmepsins share highly similar subsite specificities. In the S3 and S2 subsites, the plasmepsin 4 orthologs all preferred hydrophobic amino acid residues, Phe or Ile, but rejected charged residues such as Lys or Asp. In S2' and S3' subsites, these plasmepsins tolerated both hydrophobic and hydrophilic residues. Subsite specificities of the plasmepsin 4 family of orthologs are similar to those of human cathepsins D and E, except in S3' where the plasmepsins accept substrates containing Ser significantly better than either of these human aspartic proteases. Peptidomimetic methyleneamino reduced-peptide inhibitors, which have inhibition constants in the picomolar range, were prepared for each plasmepsin 4 ortholog based upon substrate preferences. A peptidomimetic inhibitor designed for plasmepsin 4 from P. falciparum having Ser in P3' had the lowest Ki of the series of inhibitors prepared, but did not significantly improve the selectivity of the inhibitor for plasmepsin 4 versus human cathepsin D.
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Affiliation(s)
- Tang Li
- Department of Pathobiology, University of Florida, P.O. Box 110880, Gainesville, FL 32611-0880, USA
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Büngener W, Nielsen G. [Nucleic acid metabolism in experimental malaria. 3. The utilization of adenine from the adenine-nucleotide pool of the erythrocytes for the synthesis of nucleic acids in malaria parasites (Plasmodium vinckei) in vivo]. Z Tropenmed Parasitol 1969; 20:67-73. [PMID: 4909005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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