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Boncella AE, Sabo ET, Santore RM, Carter J, Whalen J, Hudspeth JD, Morrison CN. The expanding utility of iron-sulfur clusters: Their functional roles in biology, synthetic small molecules, maquettes and artificial proteins, biomimetic materials, and therapeutic strategies. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2021.214229] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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2
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Sloan MA, Aghabi D, Harding CR. Orchestrating a heist: uptake and storage of metals by apicomplexan parasites. MICROBIOLOGY (READING, ENGLAND) 2021; 167. [PMID: 34898419 PMCID: PMC7612242 DOI: 10.1099/mic.0.001114] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Megan A Sloan
- Wellcome Centre for Integrative Parasitology, Institute for Infection, Immunity and Inflammation, University of Glasgow, UK
| | - Dana Aghabi
- Wellcome Centre for Integrative Parasitology, Institute for Infection, Immunity and Inflammation, University of Glasgow, UK
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3
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Rocamora F, Gupta P, Istvan ES, Luth MR, Carpenter EF, Kümpornsin K, Sasaki E, Calla J, Mittal N, Carolino K, Owen E, Llinás M, Ottilie S, Goldberg DE, Lee MCS, Winzeler EA. PfMFR3: A Multidrug-Resistant Modulator in Plasmodium falciparum. ACS Infect Dis 2021; 7:811-825. [PMID: 33715347 PMCID: PMC8042660 DOI: 10.1021/acsinfecdis.0c00676] [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: 12/16/2022]
Abstract
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In
malaria, chemical genetics is a powerful method for assigning
function to uncharacterized genes. MMV085203 and GNF-Pf-3600 are two
structurally related napthoquinone phenotypic screening hits that
kill both blood- and sexual-stage P. falciparum parasites in the low nanomolar to low micromolar range. In order
to understand their mechanism of action, parasites from two different
genetic backgrounds were exposed to sublethal concentrations of MMV085203
and GNF-Pf-3600 until resistance emerged. Whole genome sequencing
revealed all 17 resistant clones acquired nonsynonymous mutations
in the gene encoding the orphan apicomplexan transporter PF3D7_0312500
(pfmfr3) predicted to encode a member of the major
facilitator superfamily (MFS). Disruption of pfmfr3 and testing against a panel of antimalarial compounds showed decreased
sensitivity to MMV085203 and GNF-Pf-3600 as well as other compounds
that have a mitochondrial mechanism of action. In contrast, mutations
in pfmfr3 provided no protection against compounds
that act in the food vacuole or the cytosol. A dihydroorotate dehydrogenase
rescue assay using transgenic parasite lines, however, indicated a
different mechanism of action for both MMV085203 and GNF-Pf-3600 than
the direct inhibition of cytochrome bc1. Green fluorescent protein
(GFP) tagging of PfMFR3 revealed that it localizes to the parasite
mitochondrion. Our data are consistent with PfMFR3 playing roles in
mitochondrial transport as well as drug resistance for clinically
relevant antimalarials that target the mitochondria. Furthermore,
given that pfmfr3 is naturally polymorphic, naturally
occurring mutations may lead to differential sensitivity to clinically
relevant compounds such as atovaquone.
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Affiliation(s)
- Frances Rocamora
- Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, California 92093, United States
| | - Purva Gupta
- VA San Diego Healthcare System, Medical and Research Sections, La Jolla, California 92161, United States
- Department of Medicine, Division of Pulmonary and Critical Care, University of California, San Diego, La Jolla, California 92037, United States
| | - Eva S. Istvan
- Departments of Medicine and Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri 63130, United States
| | - Madeline R. Luth
- Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, California 92093, United States
| | | | | | - Erika Sasaki
- Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, California 92093, United States
| | - Jaeson Calla
- Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, California 92093, United States
| | - Nimisha Mittal
- Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, California 92093, United States
| | - Krypton Carolino
- Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, California 92093, United States
| | - Edward Owen
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Huck Center for Malaria Research, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Manuel Llinás
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Huck Center for Malaria Research, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Sabine Ottilie
- Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, California 92093, United States
| | - Daniel E. Goldberg
- Departments of Medicine and Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri 63130, United States
| | | | - Elizabeth A. Winzeler
- Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, California 92093, United States
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4
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Ghosh S, Pathak S, Sonawat HM, Sharma S, Sengupta A. Metabolomic changes in vertebrate host during malaria disease progression. Cytokine 2018; 112:32-43. [PMID: 30057363 DOI: 10.1016/j.cyto.2018.07.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 07/16/2018] [Accepted: 07/17/2018] [Indexed: 12/24/2022]
Abstract
Metabolomics refers to top-down systems biological analysis of metabolites in biological specimens. Phenotypic proximity of metabolites makes them interesting candidates for studying biomarkers of environmental stressors such as parasitic infections. Moreover, the host-parasite interaction directly impinges upon metabolic pathways since the parasite uses the host metabolite pool as a biosynthetic resource. Malarial infection, although not recognized as a classic metabolic disorder, often leads to severe metabolic changes such as hypoglycemia and lactic acidosis. Thus, metabolomic analysis of the infection has become an invaluable tool for promoting a better understanding of the host-parasite interaction and for the development of novel therapeutics. In this review, we summarize the current knowledge obtained from metabolomic studies of malarial infection in rodent models and human patients. Metabolomic analysis of experimental rodent malaria has provided significant insights into the mechanisms of disease progression including utilization of host resources by the parasite, sexual dimorphism in metabolic phenotypes, and cellular changes in host metabolism. Moreover, these studies also provide proof of concept for prediction of cerebral malaria. On the other hand, metabolite analysis of patient biofluids generates extensive data that could be of use in identifying biomarkers of infection severity and in monitoring disease progression. Through the use of metabolomic datasets one hopes to assess crucial infection-specific issues such as clinical severity, drug resistance, therapeutic targets, and biomarkers. Also discussed are nascent or newly emerging areas of metabolomics such as pre-erythrocytic stages of the infection and the host immune response. This review is organized in four broad sections-methodologies for metabolomic analysis, rodent infection models, studies of human clinical specimens, and potential of immunometabolomics. Data summarized in this review should serve as a springboard for novel hypothesis testing and lead to a better understanding of malarial infection and parasite biology.
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Affiliation(s)
- Soumita Ghosh
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Boulevard, Philadelphia, PA 19104, USA.
| | - Sulabha Pathak
- Department of Biological Sciences, Tata Institute of Fundamental Research, 1, Homi Bhabha Road, Mumbai 400005, India
| | - Haripalsingh M Sonawat
- Department of Chemical Sciences, Tata Institute of Fundamental Research, 1, Homi Bhabha Road, Mumbai 400005, India
| | - Shobhona Sharma
- Department of Biological Sciences, Tata Institute of Fundamental Research, 1, Homi Bhabha Road, Mumbai 400005, India
| | - Arjun Sengupta
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Boulevard, Philadelphia, PA 19104, USA.
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5
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Phaiphinit S, Pattaradilokrat S, Lursinsap C, Plaimas K. In silico multiple-targets identification for heme detoxification in the human malaria parasite Plasmodium falciparum. INFECTION GENETICS AND EVOLUTION 2015; 37:237-44. [PMID: 26626103 DOI: 10.1016/j.meegid.2015.11.025] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 11/18/2015] [Accepted: 11/24/2015] [Indexed: 12/14/2022]
Abstract
Detoxification of hemoglobin byproducts or free heme is an essential step and considered potential targets for anti-malaria drug development. However, most of anti-malaria drugs are no longer effective due to the emergence and spread of the drug resistant malaria parasites. Therefore, it is an urgent need to identify potential new targets and even for target combinations for effective malaria drug design. In this work, we reconstructed the metabolic networks of Plasmodium falciparum and human red blood cells for the simulation of steady mass and flux flows of the parasite's metabolites under the blood environment by flux balance analysis (FBA). The integrated model, namely iPF-RBC-713, was then adjusted into two stage-specific metabolic models, which first was for the pathological stage metabolic model of the parasite when invaded the red blood cell without any treatment and second was for the treatment stage of the parasite when a drug acted by inhibiting the hemozoin formation and caused high production rate of heme toxicity. The process of identifying target combinations consisted of two main steps. Firstly, the optimal fluxes of reactions in both the pathological and treatment stages were computed and compared to determine the change of fluxes. Corresponding enzymes of the reactions with zero fluxes in the treatment stage but non-zero fluxes in the pathological stage were predicted as a preliminary list of potential targets in inhibiting heme detoxification. Secondly, the combinations of all possible targets listed in the first step were examined to search for the best promising target combinations resulting in more effective inhibition of the detoxification to kill the malaria parasites. Finally, twenty-three enzymes were identified as a preliminary list of candidate targets which mostly were in pyruvate metabolism and citrate cycle. The optimal set of multiple targets for blocking the detoxification was a set of heme ligase, adenosine transporter, myo-inositol 1-phosphate synthase, ferrodoxim reductase-like protein and guanine transporter. In conclusion, the method has shown an effective and efficient way to identify target combinations which are obviously useful in the development of novel antimalarial drug combinations.
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Affiliation(s)
- Suthat Phaiphinit
- Advanced Virtual and Intelligent Computing (AVIC) Research Center, Department of Mathematics and Computer Science, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
| | | | - Chidchanok Lursinsap
- Advanced Virtual and Intelligent Computing (AVIC) Research Center, Department of Mathematics and Computer Science, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
| | - Kitiporn Plaimas
- Advanced Virtual and Intelligent Computing (AVIC) Research Center, Department of Mathematics and Computer Science, Faculty of Science, Chulalongkorn University, Bangkok, Thailand.
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6
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Figueroa-Angulo EE, Calla-Choque JS, Mancilla-Olea MI, Arroyo R. RNA-Binding Proteins in Trichomonas vaginalis: Atypical Multifunctional Proteins. Biomolecules 2015; 5:3354-95. [PMID: 26703754 PMCID: PMC4693282 DOI: 10.3390/biom5043354] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 11/07/2015] [Accepted: 11/12/2015] [Indexed: 01/08/2023] Open
Abstract
Iron homeostasis is highly regulated in vertebrates through a regulatory system mediated by RNA-protein interactions between the iron regulatory proteins (IRPs) that interact with an iron responsive element (IRE) located in certain mRNAs, dubbed the IRE-IRP regulatory system. Trichomonas vaginalis, the causal agent of trichomoniasis, presents high iron dependency to regulate its growth, metabolism, and virulence properties. Although T. vaginalis lacks IRPs or proteins with aconitase activity, possesses gene expression mechanisms of iron regulation at the transcriptional and posttranscriptional levels. However, only one gene with iron regulation at the transcriptional level has been described. Recently, our research group described an iron posttranscriptional regulatory mechanism in the T. vaginalis tvcp4 and tvcp12 cysteine proteinase mRNAs. The tvcp4 and tvcp12 mRNAs have a stem-loop structure in the 5'-coding region or in the 3'-UTR, respectively that interacts with T. vaginalis multifunctional proteins HSP70, α-Actinin, and Actin under iron starvation condition, causing translation inhibition or mRNA stabilization similar to the previously characterized IRE-IRP system in eukaryotes. Herein, we summarize recent progress and shed some light on atypical RNA-binding proteins that may participate in the iron posttranscriptional regulation in T. vaginalis.
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Affiliation(s)
- Elisa E Figueroa-Angulo
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV-IPN), Av. IPN # 2508, Col. San Pedro Zacatenco, CP 07360 México, D.F., Mexico.
| | - Jaeson S Calla-Choque
- Laboratorio de Inmunopatología en Neurocisticercosis, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Av. Honorio Delgado 430, Urb. Ingeniería, S.M.P., Lima 15102, Peru.
| | - Maria Inocente Mancilla-Olea
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV-IPN), Av. IPN # 2508, Col. San Pedro Zacatenco, CP 07360 México, D.F., Mexico.
| | - Rossana Arroyo
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV-IPN), Av. IPN # 2508, Col. San Pedro Zacatenco, CP 07360 México, D.F., Mexico.
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7
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Ke H, Lewis IA, Morrisey JM, McLean KJ, Ganesan SM, Painter HJ, Mather MW, Jacobs-Lorena M, Llinás M, Vaidya AB. Genetic investigation of tricarboxylic acid metabolism during the Plasmodium falciparum life cycle. Cell Rep 2015; 11:164-74. [PMID: 25843709 DOI: 10.1016/j.celrep.2015.03.011] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Revised: 02/11/2015] [Accepted: 03/04/2015] [Indexed: 12/24/2022] Open
Abstract
New antimalarial drugs are urgently needed to control drug-resistant forms of the malaria parasite Plasmodium falciparum. Mitochondrial electron transport is the target of both existing and new antimalarials. Herein, we describe 11 genetic knockout (KO) lines that delete six of the eight mitochondrial tricarboxylic acid (TCA) cycle enzymes. Although all TCA KOs grew normally in asexual blood stages, these metabolic deficiencies halted life-cycle progression in later stages. Specifically, aconitase KO parasites arrested as late gametocytes, whereas α-ketoglutarate-dehydrogenase-deficient parasites failed to develop oocysts in the mosquitoes. Mass spectrometry analysis of (13)C-isotope-labeled TCA mutant parasites showed that P. falciparum has significant flexibility in TCA metabolism. This flexibility manifested itself through changes in pathway fluxes and through altered exchange of substrates between cytosolic and mitochondrial pools. Our findings suggest that mitochondrial metabolic plasticity is essential for parasite development.
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Affiliation(s)
- Hangjun Ke
- Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, PA 19129, USA
| | - Ian A Lewis
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Joanne M Morrisey
- Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, PA 19129, USA
| | - Kyle J McLean
- Department of Molecular Microbiology and Immunology, Johns Hopkins School of Public Health, Baltimore, MD 21205, USA
| | - Suresh M Ganesan
- Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, PA 19129, USA
| | - Heather J Painter
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Michael W Mather
- Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, PA 19129, USA
| | - Marcelo Jacobs-Lorena
- Department of Molecular Microbiology and Immunology, Johns Hopkins School of Public Health, Baltimore, MD 21205, USA
| | - Manuel Llinás
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA; Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Akhil B Vaidya
- Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, PA 19129, USA.
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8
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Clark MA, Goheen MM, Cerami C. Influence of host iron status on Plasmodium falciparum infection. Front Pharmacol 2014; 5:84. [PMID: 24834053 PMCID: PMC4018558 DOI: 10.3389/fphar.2014.00084] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Accepted: 04/04/2014] [Indexed: 01/25/2023] Open
Abstract
Iron deficiency affects one quarter of the world's population and causes significant morbidity, including detrimental effects on immune function and cognitive development. Accordingly, the World Health Organization (WHO) recommends routine iron supplementation in children and adults in areas with a high prevalence of iron deficiency. However, a large body of clinical and epidemiological evidence has accumulated which clearly demonstrates that host iron deficiency is protective against falciparum malaria and that host iron supplementation may increase the risk of malaria. Although many effective antimalarial treatments and preventive measures are available, malaria remains a significant public health problem, in part because the mechanisms of malaria pathogenesis remain obscured by the complexity of the relationships that exist between parasite virulence factors, host susceptibility traits, and the immune responses that modulate disease. Here we review (i) the clinical and epidemiological data that describes the relationship between host iron status and malaria infection and (ii) the current understanding of the biological basis for these clinical and epidemiological observations.
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Affiliation(s)
- Martha A. Clark
- Microbiology and Immunology, University of North CarolinaChapel Hill, NC, USA
| | - Morgan M. Goheen
- Microbiology and Immunology, University of North CarolinaChapel Hill, NC, USA
| | - Carla Cerami
- Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel HillChapel Hill, NC, USA
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9
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An FtsH protease is recruited to the mitochondrion of Plasmodium falciparum. PLoS One 2013; 8:e74408. [PMID: 24058559 PMCID: PMC3772908 DOI: 10.1371/journal.pone.0074408] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Accepted: 08/01/2013] [Indexed: 11/19/2022] Open
Abstract
The two organelles, apicoplast and mitochondrion, of the malaria parasite Plasmodium falciparum have unique morphology in liver and blood stages; they undergo complex branching and looping prior to division and segregation into daughter merozoites. Little is known about the molecular processes and proteins involved in organelle biogenesis in the parasite. We report the identification of an AAA+/FtsH protease homolog (PfFtsH1) that exhibits ATP- and Zn(2+)-dependent protease activity. PfFtsH1 undergoes processing, forms oligomeric assemblies, and is associated with the membrane fraction of the parasite cell. Generation of a transfectant parasite line with hemagglutinin-tagged PfFtsH1, and immunofluorescence assay with anti-PfFtsH1 Ab demonstrated that the protein localises to P. falciparum mitochondria. Phylogenetic analysis and the single transmembrane region identifiable in PfFtsH1 suggest that it is an i-AAA like inner mitochondrial membrane protein. Expression of PfFtsH1 in Escherichia coli converted a fraction of bacterial cells into division-defective filamentous forms implying a sequestering effect of the Plasmodium factor on the bacterial homolog, indicative of functional conservation with EcFtsH. These results identify a membrane-associated mitochondrial AAA+/FtsH protease as a candidate regulatory protein for organelle biogenesis in P. falciparum.
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10
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Baumgart M, Bott M. Biochemical characterisation of aconitase from Corynebacterium glutamicum. J Biotechnol 2011; 154:163-70. [DOI: 10.1016/j.jbiotec.2010.07.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2010] [Accepted: 07/01/2010] [Indexed: 10/19/2022]
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11
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Bulusu V, Jayaraman V, Balaram H. Metabolic fate of fumarate, a side product of the purine salvage pathway in the intraerythrocytic stages of Plasmodium falciparum. J Biol Chem 2011; 286:9236-45. [PMID: 21209090 PMCID: PMC3059058 DOI: 10.1074/jbc.m110.173328] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2010] [Revised: 12/17/2010] [Indexed: 11/06/2022] Open
Abstract
In aerobic respiration, the tricarboxylic acid cycle is pivotal to the complete oxidation of carbohydrates, proteins, and lipids to carbon dioxide and water. Plasmodium falciparum, the causative agent of human malaria, lacks a conventional tricarboxylic acid cycle and depends exclusively on glycolysis for ATP production. However, all of the constituent enzymes of the tricarboxylic acid cycle are annotated in the genome of P. falciparum, which implies that the pathway might have important, yet unidentified biosynthetic functions. Here we show that fumarate, a side product of the purine salvage pathway and a metabolic intermediate of the tricarboxylic acid cycle, is not a metabolic waste but is converted to aspartate through malate and oxaloacetate. P. falciparum-infected erythrocytes and free parasites incorporated [2,3-(14)C]fumarate into the nucleic acid and protein fractions. (13)C NMR of parasites incubated with [2,3-(13)C]fumarate showed the formation of malate, pyruvate, lactate, and aspartate but not citrate or succinate. Further, treatment of free parasites with atovaquone inhibited the conversion of fumarate to aspartate, thereby indicating this pathway as an electron transport chain-dependent process. This study, therefore, provides a biosynthetic function for fumarate hydratase, malate quinone oxidoreductase, and aspartate aminotransferase of P. falciparum.
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Affiliation(s)
- Vinay Bulusu
- From the Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560 064, Karnataka, India
| | - Vijay Jayaraman
- From the Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560 064, Karnataka, India
| | - Hemalatha Balaram
- From the Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560 064, Karnataka, India
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12
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Olszewski KL, Llinás M. Central carbon metabolism of Plasmodium parasites. Mol Biochem Parasitol 2010; 175:95-103. [PMID: 20849882 DOI: 10.1016/j.molbiopara.2010.09.001] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Revised: 09/01/2010] [Accepted: 09/02/2010] [Indexed: 12/22/2022]
Abstract
The central role of metabolic perturbation to the pathology of malaria, the promise of antimetabolites as antimalarial drugs and a basic scientific interest in understanding this fascinating example of highly divergent microbial metabolism has spurred a major and concerted research effort towards elucidating the metabolic network of the Plasmodium parasites. Central carbon metabolism, broadly comprising the flow of carbon from nutrients into biomass, has been a particular focus due to clear and early indications that it plays an essential role in this network. Decades of painstaking efforts have significantly clarified our understanding of these pathways of carbon flux, and this foundational knowledge, coupled with the advent of advanced analytical technologies, have set the stage for the development of a holistic, network-level model of plasmodial carbon metabolism. In this review we summarize the current state of knowledge regarding central carbon metabolism and suggest future avenues of research. We focus primarily on the blood stages of Plasmodium falciparum, the most lethal of the human malaria parasites, but also integrate results from simian, avian and rodent models of malaria that were a major focus of early investigations into plasmodial metabolism.
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Affiliation(s)
- Kellen L Olszewski
- Department of Molecular Biology & Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
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13
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Olszewski KL, Mather MW, Morrisey JM, Garcia BA, Vaidya AB, Rabinowitz JD, Llinás M. Branched tricarboxylic acid metabolism in Plasmodium falciparum. Nature 2010; 466:774-8. [PMID: 20686576 PMCID: PMC2917841 DOI: 10.1038/nature09301] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2010] [Accepted: 06/11/2010] [Indexed: 12/25/2022]
Abstract
A central hub of carbon metabolism is the tricarboxylic acid cycle, which serves to connect the processes of glycolysis, gluconeogenesis, respiration, amino acid synthesis and other biosynthetic pathways. The protozoan intracellular malaria parasites (Plasmodium spp.), however, have long been suspected of possessing a significantly streamlined carbon metabolic network in which tricarboxylic acid metabolism plays a minor role. Blood-stage Plasmodium parasites rely almost entirely on glucose fermentation for energy and consume minimal amounts of oxygen, yet the parasite genome encodes all of the enzymes necessary for a complete tricarboxylic acid cycle. Here, by tracing (13)C-labelled compounds using mass spectrometry we show that tricarboxylic acid metabolism in the human malaria parasite Plasmodium falciparum is largely disconnected from glycolysis and is organized along a fundamentally different architecture from the canonical textbook pathway. We find that this pathway is not cyclic, but rather is a branched structure in which the major carbon sources are the amino acids glutamate and glutamine. As a consequence of this branched architecture, several reactions must run in the reverse of the standard direction, thereby generating two-carbon units in the form of acetyl-coenzyme A. We further show that glutamine-derived acetyl-coenzyme A is used for histone acetylation, whereas glucose-derived acetyl-coenzyme A is used to acetylate amino sugars. Thus, the parasite has evolved two independent production mechanisms for acetyl-coenzyme A with different biological functions. These results significantly clarify our understanding of the Plasmodium metabolic network and highlight the ability of altered variants of central carbon metabolism to arise in response to unique environments.
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Affiliation(s)
- Kellen L. Olszewski
- Department of Molecular Biology & Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544
| | - Michael W. Mather
- Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, PA 19129
| | - Joanne M. Morrisey
- Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, PA 19129
| | - Benjamin A. Garcia
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544
| | - Akhil B. Vaidya
- Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, PA 19129
| | - Joshua D. Rabinowitz
- Department of Chemistry & Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544
| | - Manuel Llinás
- Department of Molecular Biology & Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544
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14
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Kumar A, Tanveer A, Biswas S, Ram EVSR, Gupta A, Kumar B, Habib S. Nuclear-encoded DnaJ homologue of Plasmodium falciparum interacts with replication ori of the apicoplast genome. Mol Microbiol 2010; 75:942-56. [PMID: 20487289 DOI: 10.1111/j.1365-2958.2009.07033.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The apicoplast of Plasmodium falciparum carries a 35 kb circular genome (plDNA) that replicates at the late trophozoite stage of the parasite intraerythocytic cycle. plDNA replication proceeds predominantly via a d-loop/bi-directional ori mechanism with replication ori localized within inverted repeat region. Although replication of the apicoplast genome is a validated drug target, the proteins involved in the replication process are only partially characterized. We analysed DNA-protein interactions at a plDNA replication ori region and report the identification of a nuclear-encoded DnaJ homologue that binds directly to ori elements of the plDNA molecule. PfDnaJ(A) interacted with the minor groove of the DNA double-helix and recognized a 13 bp sequence within the ori. Inhibition of binding with anti-PfDnaJ(A) antibodies confirmed identity of the protein in DNA-binding experiments with organellar protein fractions. The DNA-binding domain of the approximately 69 kDa PfDnaJ(A) lay within the N-terminal 38 kDa region that carries DnaJ signature motifs. In contrast to PfDnaJ(A) in parasite organellar fractions, the recombinant protein interacted with DNA in a sequence non-specific manner. Our results suggest a role for PfDnaJ(A) in replication/repair of the apicoplast genome.
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Affiliation(s)
- Ambrish Kumar
- Division of Molecular and Structural Biology, Central Drug Research Institute, Lucknow 226001, India
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15
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Janneh O, Anwar T, Jungbauer C, Kopp S, Khoo SH, Back DJ, Chiba P. P-glycoprotein, multidrug resistance-associated proteins and human organic anion transporting polypeptide influence the intracellular accumulation of atazanavir. Antivir Ther 2010; 14:965-74. [PMID: 19918100 DOI: 10.3851/imp1399] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
BACKGROUND Drug efflux (for example, P-glycoprotein [P-gp], multidrug resistance-associated proteins [MRPs] and breast cancer resistance protein [BCRP]) and influx (for example, human organic anion transporting polypeptide [hOCTP] or human organic anion transporting polypeptide [hOATP]) transporters alter the cellular concentrations of some HIV protease inhibitors (HPIs). Here, we studied the lipophilicity and uptake of [(3)H]-atazanavir (ATV) in CEM (parental), CEM(VBL) (P-gp-overexpressing), CEM(E1000) (MRP1-overexpressing) and peripheral blood mononuclear cells (PBMCs), and evaluate the effects of modulators of drug transporters on uptake. METHODS Lipophilicity was measured by octanol/saline partition method. The influence of influx/efflux transporters on uptake was evaluated in the absence and presence of inhibitors of P-gp (GPV031), P-gp/BCRP (tariquidar and GF120918), P-gp/MRP1 (dipyridamole and daidzein), MRP1/2 (frusemide and genistein), hOATP/hOCTP (estrone-3-sulfate [E-3-S]) and hOATP/hOCTP/MRP (probenecid). The effects of a number of HPIs on uptake were also evaluated. Data from digitonin permeabilized cells allowed the evaluation of the contribution of cellular binding to total drug uptake, whereas the inhibitory effect of ATV on P-gp was assessed by daunomycin efflux/uptake assays. RESULTS [(3)H]-ATV is lipophilic and accumulates in the cultured cells as follows: CEM>CEM(E1000)>CEM(VBL). Tariquidar, GF120918 and daidzein significantly increased the uptake of [(3)H]-ATV in the cultured cells. By contrast, only daidzein and tipranavir significantly increased uptake in PBMCs, with tariquidar and frusemide devoid of effects, whereas dipyridamole, E-3-S, GPV031 and genistein significantly decreased accumulation. ATV inhibits P-gp activity; manipulation of uptake with digitonin suggests binding of [(3)H]-ATV to P-gp. CONCLUSIONS [(3)H]-ATV is lipophilic, a P-gp, MRP and hOATP substrate and an inhibitor of P-gp. Concomitant administration of ATV with drugs and dietary components (for example, daidzein and genistein) that interact with these transporters could alter its pharmacokinetics.
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Affiliation(s)
- Omar Janneh
- Department of Biomolecular and Sport Sciences, Coventry University, Coventry, UK.
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16
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Dubar F, Anquetin G, Pradines B, Dive D, Khalife J, Biot C. Enhancement of the antimalarial activity of ciprofloxacin using a double prodrug/bioorganometallic approach. J Med Chem 2010; 52:7954-7. [PMID: 19908867 DOI: 10.1021/jm901357n] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The derivatization of the fluoroquinolone ciprofloxacin greatly increases its antimalarial activity by combining bioorganometallic chemistry and the prodrug approach. Two new achiral compounds 2 and 4 were found to be 10- to 100-fold more active than ciprofloxacin against Plasmodium falciparum chloroquine-susceptible and chloroquine-resistant strains. These achiral derivatives killed parasites more rapidly than did ciprofloxacin. Compounds 2 and 4 were revealed to be promising leads, creating a new family of antimalarial agents.
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Affiliation(s)
- Faustine Dubar
- Universite de Lille 1, CNRS UMR 8181, ENSCL,Villeneuve d'Ascq Cedex, France
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Long-term prediction of fish growth under varying ambient temperature using a multiscale dynamic model. BMC SYSTEMS BIOLOGY 2009; 3:107. [PMID: 19903354 PMCID: PMC2786910 DOI: 10.1186/1752-0509-3-107] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/13/2009] [Accepted: 11/10/2009] [Indexed: 11/10/2022]
Abstract
Background Feed composition has a large impact on the growth of animals, particularly marine fish. We have developed a quantitative dynamic model that can predict the growth and body composition of marine fish for a given feed composition over a timespan of several months. The model takes into consideration the effects of environmental factors, particularly temperature, on growth, and it incorporates detailed kinetics describing the main metabolic processes (protein, lipid, and central metabolism) known to play major roles in growth and body composition. Results For validation, we compared our model's predictions with the results of several experimental studies. We showed that the model gives reliable predictions of growth, nutrient utilization (including amino acid retention), and body composition over a timespan of several months, longer than most of the previously developed predictive models. Conclusion We demonstrate that, despite the difficulties involved, multiscale models in biology can yield reasonable and useful results. The model predictions are reliable over several timescales and in the presence of strong temperature fluctuations, which are crucial factors for modeling marine organism growth. The model provides important improvements over existing models.
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18
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Affiliation(s)
- Akhil B. Vaidya
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania 19129;
| | - Michael W. Mather
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania 19129;
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Use and endocytosis of iron-containing proteins by Entamoeba histolytica trophozoites. INFECTION GENETICS AND EVOLUTION 2009; 9:1038-50. [PMID: 19539057 DOI: 10.1016/j.meegid.2009.05.018] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2009] [Revised: 04/16/2009] [Accepted: 05/19/2009] [Indexed: 11/20/2022]
Abstract
Iron is essential for nearly all organisms; in mammals, it is part of proteins such as haemoglobin, and it is captured by transferrin and lactoferrin. Transferrin is present in serum, and lactoferrin is secreted by the mucosa and by neutrophils at infection sites, as a host iron-withholding response, sequestering iron away from invading microorganisms. Additionally, all cells contain ferritin, which sequesters iron when its intracellular levels are increased, detoxifying and preventing damage. Liver ferritin contains 50% of iron corporal reserves. During evolution, pathogens have evolved diverse strategies to obtain iron from their hosts in order to survive. The protozoan Entamoeba histolytica invades the intestinal mucosa, causing dysentery, and the trophozoites often travel to the liver producing hepatic abscesses; thus, intestine and liver proteins could be important iron supplies for E. histolytica. We found that E. histolytica trophozoites can grow in both ferrous and ferric iron, and that they can use haemoglobin, holo-transferrin, holo-lactoferrin, and ferritin as in vitro iron sources. These proteins supported the amoeba growth throughout consecutive passages, similarly to ferric citrate. By confocal microscopy and immunoblotting, iron-binding proteins were observed specifically bound to the amoeba surface, and they were endocytosed, trafficked through the endosomal/lysosomal route, and degraded by neutral and acidic cysteine-proteases. Transferrin and ferritin were mainly internalized through clathrin-coated vesicles, and holo-lactoferrin was mainly internalized by caveola-like structures. In contrast, apo-lactoferrin bound to membrane lipids and cholesterol, inducing cell death. The results suggest that in vivo trophozoites secrete products that can destroy enterocytes, erythrocytes, and hepatocytes, releasing transferrin, haemoglobin, ferritin, and other iron-containing proteins, which, together with lactoferrin derived from neutrophils and acinar cells, could be used as abundant iron supplies by amoebas.
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Pino P, Foth BJ, Kwok LY, Sheiner L, Schepers R, Soldati T, Soldati-Favre D. Dual targeting of antioxidant and metabolic enzymes to the mitochondrion and the apicoplast of Toxoplasma gondii. PLoS Pathog 2007; 3:e115. [PMID: 17784785 PMCID: PMC1959373 DOI: 10.1371/journal.ppat.0030115] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2007] [Accepted: 06/27/2007] [Indexed: 01/05/2023] Open
Abstract
Toxoplasma gondii is an aerobic protozoan parasite that possesses mitochondrial antioxidant enzymes to safely dispose of oxygen radicals generated by cellular respiration and metabolism. As with most Apicomplexans, it also harbors a chloroplast-like organelle, the apicoplast, which hosts various biosynthetic pathways and requires antioxidant protection. Most apicoplast-resident proteins are encoded in the nuclear genome and are targeted to the organelle via a bipartite N-terminal targeting sequence. We show here that two antioxidant enzymes—a superoxide dismutase (TgSOD2) and a thioredoxin-dependent peroxidase (TgTPX1/2)—and an aconitase are dually targeted to both the apicoplast and the mitochondrion of T. gondii. In the case of TgSOD2, our results indicate that a single gene product is bimodally targeted due to an inconspicuous variation within the putative signal peptide of the organellar protein, which significantly alters its subcellular localization. Dual organellar targeting of proteins might occur frequently in Apicomplexans to serve important biological functions such as antioxidant protection and carbon metabolism. Toxoplasma gondii is a human and animal pathogen representative of the large group of Apicomplexa. Most members of this phylum contain, in addition to a tubular mitochondrion, a second endosymbiotic organelle indispensable for parasite survival, called the apicoplast. This non-photosynthetic plastid is the site of several anabolic pathways, including the biosynthesis of fatty acids, isoprenoids, iron-sulphur cluster, and heme. Virtually all enzymes active inside the apicoplast are encoded by the nuclear genome and targeted to the organelle via the endoplasmic reticulum courtesy of a bipartite amino terminal recognition sequence. The metabolic activities of the apicoplast impose a high demand for antioxidant protection. We show here that T. gondii possesses a superoxide dismutase and a peroxidase that are shared between the two organelles by an unusual mechanism of bimodal targeting whereby the nature of the signal peptide influences the destination of the protein to both organelles. Dual targeting also extends to other classical metabolic enzymes such as aconitase, uncovering unexpected metabolic pathways occurring in these organelles. In consequence, the bioinformatic predictions for plastidic or mitochondrial targeting on the basis of the characteristics of N-terminal presequences are insufficient in the absence of an experimental confirmation.
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Affiliation(s)
- Paco Pino
- Department of Microbiology and Molecular Medicine, Centre Medical Universitaire, University of Geneva, Geneva, Switzerland
| | - Bernardo Javier Foth
- Department of Microbiology and Molecular Medicine, Centre Medical Universitaire, University of Geneva, Geneva, Switzerland
| | - Lai-Yu Kwok
- Department of Microbiology and Molecular Medicine, Centre Medical Universitaire, University of Geneva, Geneva, Switzerland
| | - Lilach Sheiner
- Department of Microbiology and Molecular Medicine, Centre Medical Universitaire, University of Geneva, Geneva, Switzerland
| | - Rebecca Schepers
- Department of Biological Sciences, Imperial College London, London, United Kingdom
| | - Thierry Soldati
- Department of Biochemistry, Sciences II, University of Geneva, Geneva, Switzerland
| | - Dominique Soldati-Favre
- Department of Microbiology and Molecular Medicine, Centre Medical Universitaire, University of Geneva, Geneva, Switzerland
- * To whom correspondence should be addressed. E-mail:
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Tang Y, Cho PY, Kim TI, Hong SJ. Clonorchis sinensis: molecular cloning, enzymatic activity, and localization of yolk ferritin. J Parasitol 2007; 92:1275-80. [PMID: 17304806 DOI: 10.1645/ge-867r.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Ferritin is an intracellular protein that is involved in iron metabolism. A cDNA clone of Clonorchis sinensis (CsFtn), 565 bp long, encoded a putative polypeptide of 166 amino acids. CsFtn cDNA revealed a putative loop-stem structure similar to iron-responsive element (IRE). CsFtn polypeptide appeared homologous to the ferritin of trematodes with high sequential identity. Phylogenetic tree analysis showed that CsFtn clustered with the ferritins of other flukes. Recombinant CsFtn protein was produced and purified from an Escherichia coli system, and immune mouse serum was raised against CsFtn. Recombinant CsFtn showed iron-uptake ability. In adult C. sinensis, CsFtn protein was found to localize in vitelline follicles and eggs. Based on these results, CsFtn cDNA is considered to encode a C. sinensis yolk ferritin.
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Affiliation(s)
- Yi Tang
- Department of Parasitology, Chung-Ang University College of Medicine, Tongjak-gu, Seoul 156-756, Republic of Korea
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22
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van Dooren GG, Stimmler LM, McFadden GI. Metabolic maps and functions of the Plasmodium mitochondrion. FEMS Microbiol Rev 2006; 30:596-630. [PMID: 16774588 DOI: 10.1111/j.1574-6976.2006.00027.x] [Citation(s) in RCA: 176] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The mitochondrion of Plasmodium species is a validated drug target. However, very little is known about the functions of this organelle. In this review, we utilize data available from the Plasmodium falciparum genome sequencing project to piece together putative metabolic pathways that occur in the parasite, comparing this with the existing biochemical and cell biological knowledge. The Plasmodium mitochondrion contains both conserved and unusual features, including an active electron transport chain and many of the necessary enzymes for coenzyme Q and iron-sulphur cluster biosynthesis. It also plays an important role in pyrimidine metabolism. The mitochondrion participates in an unusual hybrid haem biosynthesis pathway, with enzymes localizing in both the mitochondrion and plastid organelles. The function of the tricarboxylic acid cycle in the mitochondrion is unclear. We discuss directions for future research into this fascinating, yet enigmatic, organelle.
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Affiliation(s)
- Giel G van Dooren
- Plant Cell Biology Research Centre, School of Botany, University of Melbourne, Parkville, Victoria, Australia
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23
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Lind MI, Missirlis F, Melefors O, Uhrigshardt H, Kirby K, Phillips JP, Söderhäll K, Rouault TA. Of two cytosolic aconitases expressed in Drosophila, only one functions as an iron-regulatory protein. J Biol Chem 2006; 281:18707-14. [PMID: 16679315 DOI: 10.1074/jbc.m603354200] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
In mammalian cells, iron homeostasis is largely regulated by post-transcriptional control of gene expression through the binding of iron-regulatory proteins (IRP1 and IRP2) to iron-responsive elements (IREs) contained in the untranslated regions of target mRNAs. IRP2 is the dominant iron sensor in mammalian cells under normoxia, but IRP1 is the more ancient protein in evolutionary terms and has an additional function as a cytosolic aconitase. The Caenorhabditis elegans genome does not contain an IRP2 homolog or identifiable IREs; its IRP1 homolog has aconitase activity but does not bind to mammalian IREs. The Drosophila genome offers an evolutionary intermediate containing two IRP1-like proteins (IRP-1A and IRP-1B) and target genes with IREs. Here, we used purified recombinant IRP-1A and IRP-1B from Drosophila melanogaster and showed that only IRP-1A can bind to IREs, although both proteins possess aconitase activity. These results were also corroborated in whole-fly homogenates from transgenic flies that overexpress IRP-1A and IRP-1B in their fat bodies. Ubiquitous and muscle-specific overexpression of IRP-1A, but not of IRP-1B, resulted in pre-adult lethality, underscoring the importance of the biochemical difference between the two proteins. Domain-swap experiments showed that multiple amino acid substitutions scattered throughout the IRP1 domains are synergistically required for conferring IRE binding activity. Our data suggest that as a first step during the evolution of the IRP/IRE system, the ancient cytosolic aconitase was duplicated in insects with one variant acquiring IRE-specific binding.
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Affiliation(s)
- Maria I Lind
- Department of Comparative Physiology, Evolutionary Biology Centre, Uppsala University, S-75236 Uppsala, Sweden.
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