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Li SA, Meng XY, Zhang YJ, Chen CL, Jiao YX, Zhu YQ, Liu PP, Sun W. Progress in pH-Sensitive sensors: essential tools for organelle pH detection, spotlighting mitochondrion and diverse applications. Front Pharmacol 2024; 14:1339518. [PMID: 38269286 PMCID: PMC10806205 DOI: 10.3389/fphar.2023.1339518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 12/20/2023] [Indexed: 01/26/2024] Open
Abstract
pH-sensitive fluorescent proteins have revolutionized the field of cellular imaging and physiology, offering insight into the dynamic pH changes that underlie fundamental cellular processes. This comprehensive review explores the diverse applications and recent advances in the use of pH-sensitive fluorescent proteins. These remarkable tools enable researchers to visualize and monitor pH variations within subcellular compartments, especially mitochondria, shedding light on organelle-specific pH regulation. They play pivotal roles in visualizing exocytosis and endocytosis events in synaptic transmission, monitoring cell death and apoptosis, and understanding drug effects and disease progression. Recent advancements have led to improved photostability, pH specificity, and subcellular targeting, enhancing their utility. Techniques for multiplexed imaging, three-dimensional visualization, and super-resolution microscopy are expanding the horizon of pH-sensitive protein applications. The future holds promise for their integration into optogenetics and drug discovery. With their ever-evolving capabilities, pH-sensitive fluorescent proteins remain indispensable tools for unravelling cellular dynamics and driving breakthroughs in biological research. This review serves as a comprehensive resource for researchers seeking to harness the potential of pH-sensitive fluorescent proteins.
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Affiliation(s)
- Shu-Ang Li
- Clinical Systems Biology Laboratories, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Xiao-Yan Meng
- Clinical Systems Biology Laboratories, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
- The Academy of Medical Sciences, Zhengzhou University, Zhengzhou, China
| | - Ying-Jie Zhang
- Clinical Systems Biology Laboratories, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
- The Academy of Medical Sciences, Zhengzhou University, Zhengzhou, China
| | - Cai-Li Chen
- Department of Immunology, School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, Henan, China
| | - Yu-Xue Jiao
- Clinical Systems Biology Laboratories, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Yong-Qing Zhu
- Clinical Systems Biology Laboratories, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
- The Academy of Medical Sciences, Zhengzhou University, Zhengzhou, China
| | - Pei-Pei Liu
- Clinical Systems Biology Laboratories, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Wei Sun
- Department of Burn and Repair Reconstruction, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
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2
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Scott AF, Deery E, Lawrence AD, Warren MJ. Plasmodium falciparum hydroxymethylbilane synthase does not house any cosynthase activity within the haem biosynthetic pathway. MICROBIOLOGY-SGM 2021; 167. [PMID: 34661520 PMCID: PMC8698207 DOI: 10.1099/mic.0.001095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Uroporphyrinogen III, the universal progenitor of macrocyclic, modified tetrapyrroles, is produced from aminolaevulinic acid (ALA) by a conserved pathway involving three enzymes: porphobilinogen synthase (PBGS), hydroxymethylbilane synthase (HmbS) and uroporphyrinogen III synthase (UroS). The gene encoding uroporphyrinogen III synthase has not yet been identified in Plasmodium falciparum, but it has been suggested that this activity is housed inside a bifunctional hybroxymethylbilane synthase (HmbS). Additionally, an unknown protein encoded by PF3D7_1247600 has also been predicted to possess UroS activity. In this study it is demonstrated that neither of these proteins possess UroS activity and the real UroS remains to be identified. This was demonstrated by the failure of codon-optimized genes to complement a defined Escherichia coli hemD− mutant (SASZ31) deficient in UroS activity. Furthermore, HPLC analysis of the oxidized reaction product from recombinant, purified P. falciparum HmbS showed that only uroporphyrin I could be detected (corresponding to hydroxymethylbilane production). No uroporphyrin III was detected, showing that P. falciparum HmbS does not have UroS activity and can only catalyze the formation of hydroxymethylbilane from porphobilinogen.
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Affiliation(s)
- Alan F. Scott
- School of Biosciences, University of Kent, Canterbury, Kent, CT2 7NJ, UK
- Present address: School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK
- *Correspondence: Alan F. Scott,
| | - Evelyne Deery
- School of Biosciences, University of Kent, Canterbury, Kent, CT2 7NJ, UK
| | - Andrew D. Lawrence
- School of Biosciences, University of Kent, Canterbury, Kent, CT2 7NJ, UK
| | - Martin J. Warren
- School of Biosciences, University of Kent, Canterbury, Kent, CT2 7NJ, UK
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
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3
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Kořený L, Oborník M, Horáková E, Waller RF, Lukeš J. The convoluted history of haem biosynthesis. Biol Rev Camb Philos Soc 2021; 97:141-162. [PMID: 34472688 DOI: 10.1111/brv.12794] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 08/12/2021] [Accepted: 08/19/2021] [Indexed: 01/14/2023]
Abstract
The capacity of haem to transfer electrons, bind diatomic gases, and catalyse various biochemical reactions makes it one of the essential biomolecules on Earth and one that was likely used by the earliest forms of cellular life. Since the description of haem biosynthesis, our understanding of this multi-step pathway has been almost exclusively derived from a handful of model organisms from narrow taxonomic contexts. Recent advances in genome sequencing and functional studies of diverse and previously neglected groups have led to discoveries of alternative routes of haem biosynthesis that deviate from the 'classical' pathway. In this review, we take an evolutionarily broad approach to illuminate the remarkable diversity and adaptability of haem synthesis, from prokaryotes to eukaryotes, showing the range of strategies that organisms employ to obtain and utilise haem. In particular, the complex evolutionary histories of eukaryotes that involve multiple endosymbioses and horizontal gene transfers are reflected in the mosaic origin of numerous metabolic pathways with haem biosynthesis being a striking case. We show how different evolutionary trajectories and distinct life strategies resulted in pronounced tensions and differences in the spatial organisation of the haem biosynthesis pathway, in some cases leading to a complete loss of a haem-synthesis capacity and, rarely, even loss of a requirement for haem altogether.
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Affiliation(s)
- Luděk Kořený
- Department of Biochemistry, University of Cambridge, Hopkins Building, Tennis Court Road, Cambridge, CB2 1QW, U.K
| | - Miroslav Oborník
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branišovská 31, České Budějovice (Budweis), 370 05, Czech Republic.,Faculty of Sciences, University of South Bohemia, Branišovská, České Budějovice (Budweis), 31, Czech Republic
| | - Eva Horáková
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branišovská 31, České Budějovice (Budweis), 370 05, Czech Republic
| | - Ross F Waller
- Department of Biochemistry, University of Cambridge, Hopkins Building, Tennis Court Road, Cambridge, CB2 1QW, U.K
| | - Julius Lukeš
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branišovská 31, České Budějovice (Budweis), 370 05, Czech Republic.,Faculty of Sciences, University of South Bohemia, Branišovská, České Budějovice (Budweis), 31, Czech Republic
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4
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Kita K. [Development of Medicines for Infectious Diseases -Malaria]. YAKUGAKU ZASSHI 2020; 140:887-894. [PMID: 32612051 DOI: 10.1248/yakushi.19-00255-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In developed countries, it is said that "threats of infectious diseases are already thought as things of the past". However, as you can see in the case of Ebola hemorrhagic fever that occurred in West Africa, this is a big mistake. Among infectious diseases, only smallpox has been successfully eradicated worldwide. In addition to the three major infectious diseases of HIV/AIDS, tuberculosis, and malaria, there is another group called emerging and reemerging infectious diseases. Recently, neglected tropical diseases (NTDs) have been listed as threats by the WHO, as have drug-resistant bacteria. The spread of these pathogens is increasing due to an increase in global travel. Malaria and more than half of the NTDs are parasitic diseases, such as trypanosomiasis and soil-borne helminthiasis. These are caused by parasites, with eukaryotes similar to their host mammals. In the case of these NTDs, protective immune responses induced by differences between a pathogen and host do not work well, and there is no vaccine against parasites. As for drugs developed to treat these diseases, because the properties of enzymes and target receptors are very similar, and effective drugs simultaneously show efficacy against both the disease and the host, severe side effects often occur. Therefore, the search for targets specifically present in parasites, and screening for drugs that inhibit their physiological functions, is extremely important. Here, as an example of the development of antiparasitic drugs, I will introduce a study on malaria.
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Affiliation(s)
- Kiyoshi Kita
- School of Tropical Medicine and Global Health, Nagasaki University
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5
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Kloehn J, Harding CR, Soldati-Favre D. Supply and demand-heme synthesis, salvage and utilization by Apicomplexa. FEBS J 2020; 288:382-404. [PMID: 32530125 DOI: 10.1111/febs.15445] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 05/23/2020] [Accepted: 06/05/2020] [Indexed: 01/05/2023]
Abstract
The Apicomplexa phylum groups important human and animal pathogens that cause severe diseases, encompassing malaria, toxoplasmosis, and cryptosporidiosis. In common with most organisms, apicomplexans rely on heme as cofactor for several enzymes, including cytochromes of the electron transport chain. This heme derives from de novo synthesis and/or the development of uptake mechanisms to scavenge heme from their host. Recent studies have revealed that heme synthesis is essential for Toxoplasma gondii tachyzoites, as well as for the mosquito and liver stages of Plasmodium spp. In contrast, the erythrocytic stages of the malaria parasites rely on scavenging heme from the host red blood cell. The unusual heme synthesis pathway in Apicomplexa spans three cellular compartments and comprises enzymes of distinct ancestral origin, providing promising drug targets. Remarkably given the requirement for heme, T. gondii can tolerate the loss of several heme synthesis enzymes at a high fitness cost, while the ferrochelatase is essential for survival. These findings indicate that T. gondii is capable of salvaging heme precursors from its host. Furthermore, heme is implicated in the activation of the key antimalarial drug artemisinin. Recent findings established that a reduction in heme availability corresponds to decreased sensitivity to artemisinin in T. gondii and Plasmodium falciparum, providing insights into the possible development of combination therapies to tackle apicomplexan parasites. This review describes the microeconomics of heme in Apicomplexa, from supply, either from de novo synthesis or scavenging, to demand by metabolic pathways, including the electron transport chain.
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Affiliation(s)
- Joachim Kloehn
- Department of Microbiology and Molecular Medicine, CMU, University of Geneva, Switzerland
| | - Clare R Harding
- Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity & Inflammation, University of Glasgow, UK
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6
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Tjhin ET, Hayward JA, McFadden GI, van Dooren GG. Characterization of the apicoplast-localized enzyme TgUroD in Toxoplasma gondii reveals a key role of the apicoplast in heme biosynthesis. J Biol Chem 2020; 295:1539-1550. [PMID: 31914409 PMCID: PMC7008375 DOI: 10.1074/jbc.ra119.011605] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 12/21/2019] [Indexed: 12/29/2022] Open
Abstract
Apicomplexan parasites such as Toxoplasma gondii possess an unusual heme biosynthesis pathway whose enzymes localize to the mitochondrion, cytosol, or apicoplast, a nonphotosynthetic plastid present in most apicomplexans. To characterize the involvement of the apicoplast in the T. gondii heme biosynthesis pathway, we investigated the role of the apicoplast-localized enzyme uroporphyrinogen III decarboxylase (TgUroD). We found that TgUroD knockdown impaired parasite proliferation, decreased free heme levels in the parasite, and decreased the abundance of heme-containing c-type cytochrome proteins in the parasite mitochondrion. We validated the effects of heme loss on mitochondrial cytochromes by knocking down cytochrome c/c1 heme lyase 1 (TgCCHL1), a mitochondrial enzyme that catalyzes the covalent attachment of heme to c-type cytochromes. TgCCHL1 depletion reduced parasite proliferation and decreased the abundance of c-type cytochromes. We further sought to characterize the overall importance of TgUroD and TgCCHL1 for both mitochondrial and general parasite metabolism. TgUroD depletion decreased cellular ATP levels, mitochondrial oxygen consumption, and extracellular acidification rates. By contrast, depletion of TgCCHL1 neither diminished ATP levels in the parasite nor impaired extracellular acidification rate, but resulted in specific defects in mitochondrial oxygen consumption. Together, our results indicate that the apicoplast has a key role in heme biology in T. gondii and is important for both mitochondrial and general parasite metabolism. Our study highlights the importance of heme and its synthesis in these parasites.
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Affiliation(s)
- Edwin T Tjhin
- Research School of Biology, Australian National University, Canberra, ACT 2601, Australia
| | - Jenni A Hayward
- Research School of Biology, Australian National University, Canberra, ACT 2601, Australia
| | - Geoffrey I McFadden
- School of BioSciences University of Melbourne, Parkville, VIC 3010, Australia
| | - Giel G van Dooren
- Research School of Biology, Australian National University, Canberra, ACT 2601, Australia.
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Sharma D, Soni R, Rai P, Sharma B, Bhatt TK. Relict plastidic metabolic process as a potential therapeutic target. Drug Discov Today 2017; 23:134-140. [PMID: 28987288 DOI: 10.1016/j.drudis.2017.09.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 09/03/2017] [Accepted: 09/27/2017] [Indexed: 12/16/2022]
Abstract
The alignment of the evolutionary history of parasites with that of plants provides a different panorama in the drug development process. The housing of different metabolic processes, essential for parasite survival, adds to the indispensability of the apicoplast. The different pathways responsible for fueling the apicoplast and parasite offer a myriad of proteins responsible for the apicoplast function. The studies emphasizing the target-based approaches might help in the discovery of antimalarials. The different putative drug targets and their roles are highlighted. In addition, the origin of the apicoplast and metabolic processes are reviewed and the different drugs acting upon the enzymes of the apicoplast are discussed.
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Affiliation(s)
- Drista Sharma
- Department of Biotechnology, Central University of Rajasthan, NH-8, Bandarsindri, Rajasthan 305801, India
| | - Rani Soni
- Department of Biotechnology, Central University of Rajasthan, NH-8, Bandarsindri, Rajasthan 305801, India
| | - Praveen Rai
- Department of Biotechnology, Central University of Rajasthan, NH-8, Bandarsindri, Rajasthan 305801, India
| | - Bhaskar Sharma
- Department of Biotechnology, Central University of Rajasthan, NH-8, Bandarsindri, Rajasthan 305801, India
| | - Tarun Kumar Bhatt
- Department of Biotechnology, Central University of Rajasthan, NH-8, Bandarsindri, Rajasthan 305801, India.
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8
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McFadden GI, Yeh E. The apicoplast: now you see it, now you don't. Int J Parasitol 2016; 47:137-144. [PMID: 27773518 DOI: 10.1016/j.ijpara.2016.08.005] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 08/19/2016] [Accepted: 08/25/2016] [Indexed: 10/20/2022]
Abstract
Parasites such as Plasmodium and Toxoplasma possess a vestigial plastid homologous to the chloroplasts of algae and plants. The plastid (known as the apicoplast; for apicomplexan plastid) is non-photosynthetic and very much reduced, but has clear endosymbiotic ancestry including a circular genome that encodes RNAs and proteins and a suite of bacterial biosynthetic pathways. Here we review the initial discovery of the apicoplast, and recount the major new insights into apicoplast origin, biogenesis and function. We conclude by examining how the apicoplast can be removed from malaria parasites in vitro, ultimately completing its reduction by chemical supplementation.
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Affiliation(s)
| | - Ellen Yeh
- Department of Biochemistry, Stanford Medical School, Stanford, CA, USA; Department of Pathology, Stanford Medical School, Stanford, CA, USA
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9
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Distinct Prominent Roles for Enzymes of Plasmodium berghei Heme Biosynthesis in Sporozoite and Liver Stage Maturation. Infect Immun 2016; 84:3252-3262. [PMID: 27600503 DOI: 10.1128/iai.00148-16] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 08/29/2016] [Indexed: 11/20/2022] Open
Abstract
Malarial parasites have evolved complex regulation of heme supply and disposal to adjust to heme-rich and -deprived host environments. In addition to its own pathway for heme biosynthesis, Plasmodium likely harbors mechanisms for heme scavenging from host erythrocytes. Elaborate compartmentalization of de novo heme synthesis into three subcellular locations, including the vestigial plastid organelle, indicates critical roles in life cycle progression. In this study, we systematically profile the essentiality of heme biosynthesis by targeted gene deletion of enzymes in early steps of this pathway. We show that disruption of endogenous heme biosynthesis leads to a first detectable defect in oocyst maturation and sporogony in the Anopheles vector, whereas blood stage propagation, colonization of mosquito midguts, or initiation of oocyst development occurs indistinguishably from that of wild-type parasites. Although sporozoites are produced by parasites lacking an intact pathway for heme biosynthesis, they are absent from mosquito salivary glands, indicative of a vital role for heme biosynthesis only in sporozoite maturation. Rescue of the first defect in sporogony permitted analysis of potential roles in liver stages. We show that liver stage parasites benefit from but do not strictly depend upon their own aminolevulinic acid synthase and that they can scavenge aminolevulinic acid from the host environment. Together, our experimental genetics analysis of Plasmodium enzymes for heme biosynthesis exemplifies remarkable shifts between the use of endogenous and host resources during life cycle progression.
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10
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Padma Priya P, Grover M, Tatu US, Natarajan V. Characterization of Precursor PfHsp60 in Plasmodium falciparum Cytosol during Its Asexual Development in Human Erythrocytes. PLoS One 2015; 10:e0136401. [PMID: 26317863 PMCID: PMC4552884 DOI: 10.1371/journal.pone.0136401] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Accepted: 08/03/2015] [Indexed: 11/18/2022] Open
Abstract
Mitochondrial heat shock protein 60 (Hsp60) is a nuclear encoded gene product that gets post-translationally translocated into the mitochondria. Using multiple approaches such as immunofluorescence experiments, isoelectric point analysis with two-dimensional gel electrophoresis, and mass spectrometric identification of the signal peptide, we show that Hsp60 from Plasmodium falciparum (PfHsp60) accumulates in the parasite cytoplasm during the ring, trophozoite, and schizont stages of parasite development before being imported into the parasite mitochondria. Using co-immunoprecipitation experiments with antibodies specific to cytoplasmic PfHsp90, PfHsp70-1, and PfHsp60, we show association of precursor PfHsp60 with cytoplasmic chaperone machinery. Metabolic labeling involving pulse and chase indicates translocation of the precursor pool into the parasite mitochondrion during chase. Analysis of results obtained with Geldanamycin treatment confirmed precursor PfHsp60 to be one of the clients for PfHsp90. Cytosolic chaperones bind precursor PfHsp60 prior to its import into the mitochondrion of the parasite. Our data suggests an inefficient co-ordination in the synthesis and translocation of mitochondrial PfHsp60 during asexual growth of malaria parasite in human erythrocytes.
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Affiliation(s)
- P. Padma Priya
- Department of Physics, Indian Institute of Science, Bangalore, Karnataka, India
- Department of Biochemistry, Indian Institute of Science, Bangalore, Karnataka, India
| | - Manish Grover
- Department of Biochemistry, Indian Institute of Science, Bangalore, Karnataka, India
| | - Utpal S. Tatu
- Department of Biochemistry, Indian Institute of Science, Bangalore, Karnataka, India
| | - Vasant Natarajan
- Department of Physics, Indian Institute of Science, Bangalore, Karnataka, India
- * E-mail:
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11
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Ke H, Sigala PA, Miura K, Morrisey JM, Mather MW, Crowley JR, Henderson JP, Goldberg DE, Long CA, Vaidya AB. The heme biosynthesis pathway is essential for Plasmodium falciparum development in mosquito stage but not in blood stages. J Biol Chem 2014; 289:34827-37. [PMID: 25352601 DOI: 10.1074/jbc.m114.615831] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Heme is an essential cofactor for aerobic organisms. Its redox chemistry is central to a variety of biological functions mediated by hemoproteins. In blood stages, malaria parasites consume most of the hemoglobin inside the infected erythrocytes, forming nontoxic hemozoin crystals from large quantities of heme released during digestion. At the same time, the parasites possess a heme de novo biosynthetic pathway. This pathway in the human malaria parasite Plasmodium falciparum has been considered essential and is proposed as a potential drug target. However, we successfully disrupted the first and last genes of the pathway, individually and in combination. These knock-out parasite lines, lacking 5-aminolevulinic acid synthase and/or ferrochelatase (FC), grew normally in blood-stage culture and exhibited no changes in sensitivity to heme-related antimalarial drugs. We developed a sensitive LC-MS/MS assay to monitor stable isotope incorporation into heme from its precursor 5-[(13)C4]aminolevulinic acid, and this assay confirmed that de novo heme synthesis was ablated in FC knock-out parasites. Disrupting the FC gene also caused no defects in gametocyte generation or maturation but resulted in a greater than 70% reduction in male gamete formation and completely prevented oocyst formation in female Anopheles stephensi mosquitoes. Our data demonstrate that the heme biosynthesis pathway is not essential for asexual blood-stage growth of P. falciparum parasites but is required for mosquito transmission. Drug inhibition of pathway activity is therefore unlikely to provide successful antimalarial therapy. These data also suggest the existence of a parasite mechanism for scavenging host heme to meet metabolic needs.
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Affiliation(s)
- Hangjun Ke
- From the Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania 19129
| | - Paul A Sigala
- the Department of Molecular Microbiology and the Howard Hughes Medical Institute, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Kazutoyo Miura
- the Laboratory of Malaria and Vector Research, NIAID, National Institutes of Health, Rockville, Maryland 20852, and
| | - Joanne M Morrisey
- From the Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania 19129
| | - Michael W Mather
- From the Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania 19129
| | - Jan R Crowley
- the Center for Women's Infectious Disease Research and
| | - Jeffrey P Henderson
- the Center for Women's Infectious Disease Research and Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Daniel E Goldberg
- the Department of Molecular Microbiology and the Howard Hughes Medical Institute, Washington University School of Medicine, St. Louis, Missouri 63110, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Carole A Long
- the Laboratory of Malaria and Vector Research, NIAID, National Institutes of Health, Rockville, Maryland 20852, and
| | - Akhil B Vaidya
- From the Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania 19129,
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12
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Affiliation(s)
- Paul A. Sigala
- Departments of Medicine and Molecular Microbiology and the Howard Hughes Medical Institute, Washington University School of Medicine, St. Louis, Missouri 63110; ,
| | - Daniel E. Goldberg
- Departments of Medicine and Molecular Microbiology and the Howard Hughes Medical Institute, Washington University School of Medicine, St. Louis, Missouri 63110; ,
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13
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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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14
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Nagaraj VA, Sundaram B, Varadarajan NM, Subramani PA, Kalappa DM, Ghosh SK, Padmanaban G. Malaria parasite-synthesized heme is essential in the mosquito and liver stages and complements host heme in the blood stages of infection. PLoS Pathog 2013; 9:e1003522. [PMID: 23935500 PMCID: PMC3731253 DOI: 10.1371/journal.ppat.1003522] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2013] [Accepted: 06/10/2013] [Indexed: 01/21/2023] Open
Abstract
Heme metabolism is central to malaria parasite biology. The parasite acquires heme from host hemoglobin in the intraerythrocytic stages and stores it as hemozoin to prevent free heme toxicity. The parasite can also synthesize heme de novo, and all the enzymes in the pathway are characterized. To study the role of the dual heme sources in malaria parasite growth and development, we knocked out the first enzyme, δ-aminolevulinate synthase (ALAS), and the last enzyme, ferrochelatase (FC), in the heme-biosynthetic pathway of Plasmodium berghei (Pb). The wild-type and knockout (KO) parasites had similar intraerythrocytic growth patterns in mice. We carried out in vitro radiolabeling of heme in Pb-infected mouse reticulocytes and Plasmodium falciparum-infected human RBCs using [4-14C] aminolevulinic acid (ALA). We found that the parasites incorporated both host hemoglobin-heme and parasite-synthesized heme into hemozoin and mitochondrial cytochromes. The similar fates of the two heme sources suggest that they may serve as backup mechanisms to provide heme in the intraerythrocytic stages. Nevertheless, the de novo pathway is absolutely essential for parasite development in the mosquito and liver stages. PbKO parasites formed drastically reduced oocysts and did not form sporozoites in the salivary glands. Oocyst production in PbALASKO parasites recovered when mosquitoes received an ALA supplement. PbALASKO sporozoites could infect mice only when the mice received an ALA supplement. Our results indicate the potential for new therapeutic interventions targeting the heme-biosynthetic pathway in the parasite during the mosquito and liver stages. We demonstrated about two decades ago that the malaria parasite could make heme on its own, although it imports heme from red blood cell hemoglobin during the blood stages of infection. We investigated the role of parasite-synthesized heme in all stages of parasite growth by knocking out two genes in the heme-biosynthetic pathway of Plasmodium berghei that infects mice. We found that the parasite-synthesized heme complements the function of hemoglobin-heme during the blood stages. The parasite-synthesized heme appears to be a backup mechanism. The parasite incorporates both sources of heme into hemozoin, a detoxification product, and into mitochondrial cytochromes. The parasite-synthesized heme is, however, absolutely essential for parasite growth during the mosquito and liver stages. We restored the sporozoite formation and liver-stage development of the knockout parasites by providing the missing metabolite. Thus, the heme-biosynthetic pathway could be a target for antimalarial therapies in the mosquito and liver stages of infection. The knockout parasite could also be tested for its potential as a genetically attenuated sporozoite vaccine.
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Abstract
INTRODUCTION The relict plastid, or apicoplast, is a characteristic feature of Plasmodium spp. and reflects the unusual evolutionary origins of these parasites. The essential role this organelle plays in the life of the parasite, and its unusual, non-mammalian metabolism, make the apicoplast an excellent drug target. AREAS COVERED This review focuses on the biological role of the apicoplast in the erythrocytic life cycle and what that reveals about existing drug targets. We also discuss the future of the apicoplast in the development of anti-malarials, emphasizing those pathways with greatest potential as a source of novel drug targets and emphasizing the need to understand in vitro drug responses to optimize eventual use of these drugs to treat malaria. EXPERT OPINION More than a decade of research on the apicoplast has confirmed the promise of this organelle as a source of drug targets. It is now possible to rationally assess the value of existing drugs and new drug targets, and to understand the role these drugs can play in the arsenal of anti-malarial treatments.
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Affiliation(s)
- Christopher D Goodman
- University of Melbourne, School of Botany, Professor's Walk, Parkville, Vic, 3010, Australia.
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Sigala PA, Crowley JR, Hsieh S, Henderson JP, Goldberg DE. Direct tests of enzymatic heme degradation by the malaria parasite Plasmodium falciparum. J Biol Chem 2012; 287:37793-807. [PMID: 22992734 PMCID: PMC3488054 DOI: 10.1074/jbc.m112.414078] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Malaria parasites generate vast quantities of heme during blood stage infection via hemoglobin digestion and limited de novo biosynthesis, but it remains unclear if parasites metabolize heme for utilization or disposal. Recent in vitro experiments with a heme oxygenase (HO)-like protein from Plasmodium falciparum suggested that parasites may enzymatically degrade some heme to the canonical HO product, biliverdin (BV), or its downstream metabolite, bilirubin (BR). To directly test for BV and BR production by P. falciparum parasites, we DMSO-extracted equal numbers of infected and uninfected erythrocytes and developed a sensitive LC-MS/MS assay to quantify these tetrapyrroles. We found comparable low levels of BV and BR in both samples, suggesting the absence of HO activity in parasites. We further tested live parasites by targeted expression of a fluorescent BV-binding protein within the parasite cytosol, mitochondrion, and plant-like plastid. This probe could detect exogenously added BV but gave no signal indicative of endogenous BV production within parasites. Finally, we recombinantly expressed and tested the proposed heme degrading activity of the HO-like protein, PfHO. Although PfHO bound heme and protoporphyrin IX with modest affinity, it did not catalyze heme degradation in vivo within bacteria or in vitro in UV absorbance and HPLC assays. These observations are consistent with PfHO's lack of a heme-coordinating His residue and suggest an alternative function within parasites. We conclude that P. falciparum parasites lack a canonical HO pathway for heme degradation and thus rely fully on alternative mechanisms for heme detoxification and iron acquisition during blood stage infection.
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Affiliation(s)
- Paul A Sigala
- Department of Molecular Microbiology and the Howard Hughes Medical Institute, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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van Dooren GG, Kennedy AT, McFadden GI. The use and abuse of heme in apicomplexan parasites. Antioxid Redox Signal 2012; 17:634-56. [PMID: 22320355 DOI: 10.1089/ars.2012.4539] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
SIGNIFICANCE Heme is an essential prosthetic group for most life on Earth. It functions in numerous cellular redox reactions, including in antioxidant defenses and at several stages of the electron transport chain in prokaryotes and eukaryotic mitochondria. Heme also functions as a sensor and transport molecule for gases such as oxygen. Heme is a complex organic molecule and can only be synthesized through a multienzyme pathway from simpler precursors. Most free-living organisms synthesize their own heme by a broadly conserved metabolic pathway. Parasites are adept at scavenging molecules from their hosts, and heme is no exception. RECENT ADVANCES In this review we examine recent advances in understanding heme usage and acquisition in Apicomplexa, a group of parasites that include the causative agents of malaria, toxoplasmosis, and several major parasites of livestock. CRITICAL ISSUES Heme is critical to the survival of Apicomplexa, although the functions of heme in these organisms remain poorly understood. Some Apicomplexa likely scavenge heme from their host organisms, while others retain the ability to synthesize heme. Surprisingly, some Apicomplexa may be able to both synthesize and scavenge heme. Several Apicomplexa live in intracellular environments that contain high levels of heme. Since heme is toxic at high concentrations, parasites must carefully regulate intracellular heme levels and develop mechanisms to detoxify excess heme. Indeed, drugs interfering with heme detoxification serve as major antimalarials. FUTURE DIRECTIONS Understanding heme requirements and regulation in apicomplexan parasites promises to reveal multiple targets for much-needed therapeutic intervention against these parasites.
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Affiliation(s)
- Giel G van Dooren
- Research School of Biology, Australian National University, Canberra, ACT, Australia.
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18
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Abstract
Parasites like malaria and Toxoplasma possess a vestigial plastid homologous to the chloroplasts of plants. The plastid (known as the apicoplast) is non-photosynthetic but retains many hallmarks of its ancestry including a circular genome that it synthesises proteins from and a suite of biosynthetic pathways of cyanobacterial origin. In this review, the discovery of the apicoplast and its integration, function and purpose are explored. New insights into the apicoplast fatty acid biosynthesis pathway and some novel roles of the apicoplast in vaccine development are reviewed.
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Kořený L, Sobotka R, Janouškovec J, Keeling PJ, Oborník M. Tetrapyrrole synthesis of photosynthetic chromerids is likely homologous to the unusual pathway of apicomplexan parasites. THE PLANT CELL 2011; 23:3454-3462. [PMID: 21963666 PMCID: PMC3203424 DOI: 10.1105/tpc.111.089102] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Revised: 09/07/2011] [Accepted: 09/19/2011] [Indexed: 05/31/2023]
Abstract
Most photosynthetic eukaryotes synthesize both heme and chlorophyll via a common tetrapyrrole biosynthetic pathway starting from glutamate. This pathway was derived mainly from cyanobacterial predecessor of the plastid and differs from the heme synthesis of the plastid-lacking eukaryotes. Here, we show that the coral-associated alveolate Chromera velia, the closest known photosynthetic relative to Apicomplexa, possesses a tetrapyrrole pathway that is homologous to the unusual pathway of apicomplexan parasites. We also demonstrate that, unlike other eukaryotic phototrophs, Chromera synthesizes chlorophyll from glycine and succinyl-CoA rather than glutamate. Our data shed light on the evolution of the heme biosynthesis in parasitic Apicomplexa and photosynthesis-related biochemical processes in their ancestors.
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Affiliation(s)
- Luděk Kořený
- Institute of Parasitology, Biology Centre, Academy of Sciences of the Czech Republic, and Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
| | - Roman Sobotka
- Institute of Microbiology, Academy of Sciences of the Czech Republic, 37981 Třeboň, Czech Republic
| | - Jan Janouškovec
- Department of Botany, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Patrick J. Keeling
- Department of Botany, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Miroslav Oborník
- Institute of Parasitology, Biology Centre, Academy of Sciences of the Czech Republic, and Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
- Institute of Microbiology, Academy of Sciences of the Czech Republic, 37981 Třeboň, Czech Republic
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Tripodi KEJ, Menendez Bravo SM, Cricco JA. Role of heme and heme-proteins in trypanosomatid essential metabolic pathways. Enzyme Res 2011; 2011:873230. [PMID: 21603276 PMCID: PMC3092630 DOI: 10.4061/2011/873230] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Accepted: 02/07/2011] [Indexed: 11/29/2022] Open
Abstract
Around the world, trypanosomatids are known for being etiological agents of several highly disabling and often fatal diseases like Chagas disease (Trypanosoma cruzi), leishmaniasis (Leishmania spp.), and African trypanosomiasis (Trypanosoma brucei). Throughout their life cycle, they must cope with diverse environmental conditions, and the mechanisms involved in these processes are crucial for their survival. In this review, we describe the role of heme in several essential metabolic pathways of these protozoans. Notwithstanding trypanosomatids lack of the complete heme biosynthetic pathway, we focus our discussion in the metabolic role played for important heme-proteins, like cytochromes. Although several genes for different types of cytochromes, involved in mitochondrial respiration, polyunsaturated fatty acid metabolism, and sterol biosynthesis, are annotated at the Tritryp Genome Project, the encoded proteins have not yet been deeply studied. We pointed our attention into relevant aspects of these protein functions that are amenable to be considered for rational design of trypanocidal agents.
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Affiliation(s)
- Karina E J Tripodi
- Departamento de Química Biológica and Instituto de Biología Molecular y Celular de Rosario (IBR, CONICET-UNR), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, S2002LRK Rosario, Argentina
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Kořený L, Oborník M. Sequence evidence for the presence of two tetrapyrrole pathways in Euglena gracilis. Genome Biol Evol 2011; 3:359-64. [PMID: 21444293 PMCID: PMC5654406 DOI: 10.1093/gbe/evr029] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/22/2011] [Indexed: 11/16/2022] Open
Abstract
Genes encoding enzymes of the tetrapyrrole biosynthetic pathway were searched within Euglena gracilis EST databases and 454 genome reads and their 5' end regions were sequenced when not available. Phylogenetic analyses and protein localization predictions support the hypothesis concerning the presence of two separated tetrapyrrole pathways in E. gracilis. One of these pathways resembles the heme synthesis in primarily heterotrophic eukaryotes and was presumably present in the host cell prior to secondary endosymbiosis with a green alga. The second pathway is similar to the plastid-localized tetrapyrrole syntheses in plants and photosynthetic algae. It appears to be localized to the secondary plastid, presumably derived from an algal endosymbiont and probably serves only for the production of plastidial heme and chlorophyll. Thus, E. gracilis represents an evolutionary intermediate in a metabolic transformation of a primary heterotroph to a photoautotroph through secondary endosymbiosis. We propose here that the tetrapyrrole pathway serves as a highly informative marker for the evolution of plastids and plays a crucial role in the loss of plastids.
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Affiliation(s)
- Luděk Kořený
- Department of Molecular Biology of Protists, Biology Centre of the Academy of Sciences of the Czech Republic, Institute of Parasitology, České Budějovice, Czech Republic
- Department of Molecular Biology, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Miroslav Oborník
- Department of Molecular Biology of Protists, Biology Centre of the Academy of Sciences of the Czech Republic, Institute of Parasitology, České Budějovice, Czech Republic
- Department of Molecular Biology, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
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Nagaraj VA, Arumugam R, Prasad D, Rangarajan PN, Padmanaban G. Protoporphyrinogen IX oxidase from Plasmodium falciparum is anaerobic and is localized to the mitochondrion. Mol Biochem Parasitol 2010; 174:44-52. [PMID: 20603160 DOI: 10.1016/j.molbiopara.2010.06.012] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Revised: 05/21/2010] [Accepted: 06/24/2010] [Indexed: 11/19/2022]
Abstract
Earlier studies in this laboratory had shown that the malarial parasite can synthesize heme de novo and inhibition of the pathway leads to death of the parasite. It has been proposed that the pathway for the biosynthesis of heme in Plasmodium falciparum is unique involving three different cellular compartments, namely mitochondrion, apicoplast and cytosol. Experimental evidences are now available for the functionality and localization of all the enzymes of this pathway, except protoporphyrinogen IX oxidase (PfPPO), the penultimate enzyme. In the present study, PfPPO has been cloned, expressed and shown to be localized to the mitochondrion by immunofluorescence microscopy. Interestingly, the enzyme has been found to be active only under anaerobic conditions and is dependent on electron transport chain (ETC) acceptors for its activity. The native enzyme present in the parasite is inhibited by the ETC inhibitors, atovaquone and antimycin. Atovaquone, a well known inhibitor of parasite dihydroorotate dehydrogenase, dependent on the ETC, inhibits synthesis of heme as well in P. falciparum culture. A model is proposed to explain the ETC dependence of both the pyrimidine and heme-biosynthetic pathways in P. falciparum.
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Nagaraj VA, Prasad D, Arumugam R, Rangarajan PN, Padmanaban G. Characterization of coproporphyrinogen III oxidase in Plasmodium falciparum cytosol. Parasitol Int 2010. [DOI: 10.1016/j.parint.2009.12.001 10.1016/j.molbiopara.2009.05.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
Members of the phylum Apicomplexa are motile and rapidly dividing intracellular parasites, able to occupy a large spectrum of niches by infecting diverse hosts and invading various cell types. As obligate intracellular parasites, most apicomplexans only survive for a short period extracellularly, and, during this time, have a high energy demand to power gliding motility and invasion into new host cells. Similarly, these fast-replicating intracellular parasites are critically dependent on host-cell nutrients as energy and carbon sources, noticeably for the extensive membrane biogenesis imposed during growth and division. To access host-cell metabolites, the apicomplexans Toxoplasma gondii and Plasmodium falciparum have evolved strategies that exquisitely reflect adaptation to their respective niches. In the present review, we summarize and compare some recent findings regarding the energetic metabolism and carbon sources used by these two genetically tractable apicomplexans during host-cell invasion and intracellular growth and replication.
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Abstract
Most Apicomplexans possess a relic plastid named apicoplast, originating from secondary endosymbiosis of a red algae. This non-photosynthetic organelle fulfils important metabolic functions and confers sensitivity to antibiotics. The tasks of this organelle is compared across the phylum of Apicomplexa, highlighting its role in metabolic adaptation to different intracellular niches.
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Seeber F, Soldati-Favre D. Metabolic Pathways in the Apicoplast of Apicomplexa. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2010; 281:161-228. [DOI: 10.1016/s1937-6448(10)81005-6] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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Nagaraj VA, Prasad D, Arumugam R, Rangarajan PN, Padmanaban G. Characterization of coproporphyrinogen III oxidase in Plasmodium falciparum cytosol. Parasitol Int 2009; 59:121-7. [PMID: 20006984 DOI: 10.1016/j.parint.2009.12.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2009] [Revised: 11/28/2009] [Accepted: 12/07/2009] [Indexed: 10/20/2022]
Abstract
A unique hybrid pathway has been proposed for de novo heme biosynthesis in Plasmodium falciparum involving three different compartments of the parasite, namely mitochondrion, apicoplast and cytosol. While parasite mitochondrion and apicoplast have been shown to harbor key enzymes of the pathway, there has been no experimental evidence for the involvement of parasite cytosol in heme biosynthesis. In this study, a recombinant P. falciparum coproporphyrinogen III oxidase (rPfCPO) was produced in E. coli and confirmed to be active under aerobic conditions. rPfCPO behaved as a monomer of 61kDa molecular mass in gel filtration analysis. Immunofluorescence studies using antibodies to rPfCPO suggested that the enzyme was present in the parasite cytosol. These results were confirmed by detection of enzyme activity only in the parasite soluble fraction. Western blot analysis with anti-rPfCPO antibodies also revealed a 58kDa protein only in this fraction and not in the membrane fraction. The cytosolic presence of PfCPO provides evidence for a hybrid heme-biosynthetic pathway in the malarial parasite.
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