1
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Bezpalaya EY, Matyuta IO, Vorobyeva NN, Kurilova SA, Oreshkov SD, Minyaev ME, Boyko KM, Rodina EV. The crystal structure of yeast mitochondrial type pyrophosphatase provides a model to study pathological mutations in its human ortholog. Biochem Biophys Res Commun 2024; 738:150563. [PMID: 39178581 DOI: 10.1016/j.bbrc.2024.150563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2024] [Revised: 08/16/2024] [Accepted: 08/16/2024] [Indexed: 08/26/2024]
Abstract
Mutations in human ppa2 gene encoding mitochondrial inorganic pyrophosphatase (PPA2) result in the mitochondria malfunction in heart and brain and lead to early death. In comparison with its cytosolic counterpart, PPA2 of any species is a poorly characterized enzyme with a previously unknown 3D structure. We report here the crystal structure of PPA2 from yeast Ogataea parapolymorpha (OpPPA2), as well as its biochemical characterization. OpPPA2 is a dimer, demonstrating the fold typical for other eukaryotic Family I pyrophosphatases, including the human cytosolic enzyme. Cofactor Mg2+ ions found in OpPPA2 structure have similar coordination to most known Family I pyrophosphatases. Most of the residues associated with the pathological mutations in human PPA2 are conserved in OpPPA2, and their structural context suggests possible explanations for the effects of the mutations on the human enzyme. In this work, the mutant variant of OpPPA2, Met52Val, corresponding to the natural pathogenic variant Met94Val of human PPA2, is characterized. The obtained structural and biochemical data provide a step to understanding the structural basis of PPA2-associated pathologies.
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Affiliation(s)
| | - Ilya O Matyuta
- A.N. Bach Institute of Biochemistry, Federal Research Centre of Biotechnology of the Russian Academy of Sciences, 119071, Moscow, Russia; Landau Phystech School of Physics and Research, Moscow Institute of Physics and Technology, Institutsky Lane, 9, Dolgoprudny, 141700, Moscow, Russia
| | - Natalia N Vorobyeva
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119899, Moscow, Russia
| | - Svetlana A Kurilova
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119899, Moscow, Russia
| | - Sergey D Oreshkov
- Lomonosov Moscow State University, Chemistry Department, 119991, Moscow, Russia
| | - Mikhail E Minyaev
- N.D. Zelinsky Institute of Organic Chemistry Russian Academy of Sciences, 119071, Moscow, Russia
| | - Konstantin M Boyko
- A.N. Bach Institute of Biochemistry, Federal Research Centre of Biotechnology of the Russian Academy of Sciences, 119071, Moscow, Russia.
| | - Elena V Rodina
- Lomonosov Moscow State University, Chemistry Department, 119991, Moscow, Russia.
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2
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Docampo R. Advances in the cellular biology, biochemistry, and molecular biology of acidocalcisomes. Microbiol Mol Biol Rev 2024; 88:e0004223. [PMID: 38099688 PMCID: PMC10966946 DOI: 10.1128/mmbr.00042-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2024] Open
Abstract
SUMMARYAcidocalcisomes are organelles conserved during evolution and closely related to the so-called volutin granules of bacteria and archaea, to the acidocalcisome-like vacuoles of yeasts, and to the lysosome-related organelles of animal species. All these organelles have in common their acidity and high content of polyphosphate and calcium. They are characterized by a variety of functions from storage of phosphorus and calcium to roles in Ca2+ signaling, osmoregulation, blood coagulation, and inflammation. They interact with other organelles through membrane contact sites or by fusion, and have several enzymes, pumps, transporters, and channels.
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Affiliation(s)
- Roberto Docampo
- Department of Cellular Biology, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
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3
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Nascimento JF, Souza ROO, Alencar MB, Marsiccobetre S, Murillo AM, Damasceno FS, Girard RBMM, Marchese L, Luévano-Martinez LA, Achjian RW, Haanstra JR, Michels PAM, Silber AM. How much (ATP) does it cost to build a trypanosome? A theoretical study on the quantity of ATP needed to maintain and duplicate a bloodstream-form Trypanosoma brucei cell. PLoS Pathog 2023; 19:e1011522. [PMID: 37498954 PMCID: PMC10409291 DOI: 10.1371/journal.ppat.1011522] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 08/08/2023] [Accepted: 06/29/2023] [Indexed: 07/29/2023] Open
Abstract
ATP hydrolysis is required for the synthesis, transport and polymerization of monomers for macromolecules as well as for the assembly of the latter into cellular structures. Other cellular processes not directly related to synthesis of biomass, such as maintenance of membrane potential and cellular shape, also require ATP. The unicellular flagellated parasite Trypanosoma brucei has a complex digenetic life cycle. The primary energy source for this parasite in its bloodstream form (BSF) is glucose, which is abundant in the host's bloodstream. Here, we made a detailed estimation of the energy budget during the BSF cell cycle. As glycolysis is the source of most produced ATP, we calculated that a single parasite produces 6.0 x 1011 molecules of ATP/cell cycle. Total biomass production (which involves biomass maintenance and duplication) accounts for ~63% of the total energy budget, while the total biomass duplication accounts for the remaining ~37% of the ATP consumption, with in both cases translation being the most expensive process. These values allowed us to estimate a theoretical YATP of 10.1 (g biomass)/mole ATP and a theoretical [Formula: see text] of 28.6 (g biomass)/mole ATP. Flagellar motility, variant surface glycoprotein recycling, transport and maintenance of transmembrane potential account for less than 30% of the consumed ATP. Finally, there is still ~5.5% available in the budget that is being used for other cellular processes of as yet unknown cost. These data put a new perspective on the assumptions about the relative energetic weight of the processes a BSF trypanosome undergoes during its cell cycle.
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Affiliation(s)
- Janaina F. Nascimento
- Laboratory of Biochemistry of Tryps–LaBTryps, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo–São Paulo, Brazil
| | - Rodolpho O. O. Souza
- Laboratory of Biochemistry of Tryps–LaBTryps, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo–São Paulo, Brazil
| | - Mayke B. Alencar
- Laboratory of Biochemistry of Tryps–LaBTryps, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo–São Paulo, Brazil
| | - Sabrina Marsiccobetre
- Laboratory of Biochemistry of Tryps–LaBTryps, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo–São Paulo, Brazil
| | - Ana M. Murillo
- Laboratory of Biochemistry of Tryps–LaBTryps, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo–São Paulo, Brazil
| | - Flávia S. Damasceno
- Laboratory of Biochemistry of Tryps–LaBTryps, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo–São Paulo, Brazil
| | - Richard B. M. M. Girard
- Laboratory of Biochemistry of Tryps–LaBTryps, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo–São Paulo, Brazil
| | - Letícia Marchese
- Laboratory of Biochemistry of Tryps–LaBTryps, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo–São Paulo, Brazil
| | - Luis A. Luévano-Martinez
- Laboratory of Biochemistry of Tryps–LaBTryps, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo–São Paulo, Brazil
| | - Renan W. Achjian
- Laboratory of Biochemistry of Tryps–LaBTryps, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo–São Paulo, Brazil
| | - Jurgen R. Haanstra
- Systems Biology Lab, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Paul A. M. Michels
- School of Biological Sciences, The University of Edinburgh, Edinburgh, United Kingdom
| | - Ariel M. Silber
- Laboratory of Biochemistry of Tryps–LaBTryps, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo–São Paulo, Brazil
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4
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Down the membrane hole: Ion channels in protozoan parasites. PLoS Pathog 2022; 18:e1011004. [PMID: 36580479 PMCID: PMC9799330 DOI: 10.1371/journal.ppat.1011004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Parasitic diseases caused by protozoans are highly prevalent around the world, disproportionally affecting developing countries, where coinfection with other microorganisms is common. Control and treatment of parasitic infections are constrained by the lack of specific and effective drugs, plus the rapid emergence of resistance. Ion channels are main drug targets for numerous diseases, but their potential against protozoan parasites is still untapped. Ion channels are membrane proteins expressed in all types of cells, allowing for the flow of ions between compartments, and regulating cellular functions such as membrane potential, excitability, volume, signaling, and death. Channels and transporters reside at the interface between parasites and their hosts, controlling nutrient uptake, viability, replication, and infectivity. To understand how ion channels control protozoan parasites fate and to evaluate their suitability for therapeutics, we must deepen our knowledge of their structure, function, and modulation. However, methodological approaches commonly used in mammalian cells have proven difficult to apply in protozoans. This review focuses on ion channels described in protozoan parasites of clinical relevance, mainly apicomplexans and trypanosomatids, highlighting proteins for which molecular and functional evidence has been correlated with their physiological functions.
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5
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Ramakrishnan S, Baptista RP, Asady B, Huang G, Docampo R. TbVps41 regulates trafficking of endocytic but not biosynthetic cargo to lysosomes of bloodstream forms of Trypanosoma brucei. FASEB J 2021; 35:e21641. [PMID: 34041791 DOI: 10.1096/fj.202100487r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 04/15/2021] [Accepted: 04/19/2021] [Indexed: 11/11/2022]
Abstract
The bloodstream stage of Trypanosoma brucei, the causative agent of African trypanosomiasis, is characterized by its high rate of endocytosis, which is involved in remodeling of its surface coat. Here we present evidence that RNAi-mediated expression down-regulation of vacuolar protein sorting 41 (Vps41), a component of the homotypic fusion and vacuole protein sorting (HOPS) complex, leads to a strong inhibition of endocytosis, vesicle accumulation, enlargement of the flagellar pocket ("big eye" phenotype), and dramatic effect on cell growth. Unexpectedly, other functions described for Vps41 in mammalian cells and yeasts, such as delivery of proteins to lysosomes, and lysosome-related organelles (acidocalcisomes) were unaffected, indicating that in trypanosomes post-Golgi trafficking is distinct from that of mammalian cells and yeasts. The essentiality of TbVps41 suggests that it is a potential drug target.
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Affiliation(s)
| | | | - Beejan Asady
- Center for Tropical and Emerging Global Diseases, Athens, GA, USA
| | - Guozhong Huang
- Center for Tropical and Emerging Global Diseases, Athens, GA, USA
| | - Roberto Docampo
- Center for Tropical and Emerging Global Diseases, Athens, GA, USA.,Department of Cellular Biology, University of Georgia, Athens, GA, USA
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6
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Denoncourt A, Downey M. Model systems for studying polyphosphate biology: a focus on microorganisms. Curr Genet 2021; 67:331-346. [PMID: 33420907 DOI: 10.1007/s00294-020-01148-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 12/08/2020] [Accepted: 12/14/2020] [Indexed: 12/19/2022]
Abstract
Polyphosphates (polyP) are polymers of inorganic phosphates joined by high-energy bonds to form long chains. These chains are present in all forms of life but were once disregarded as 'molecular fossils'. PolyP has gained attention in recent years following new links to diverse biological roles ranging from energy storage to cell signaling. PolyP research in humans and other higher eukaryotes is limited by a lack of suitable tools and awaits the identification of enzymatic players that would enable more comprehensive studies. Therefore, many of the most important insights have come from single-cell model systems. Here, we review determinants of polyP metabolism, regulation, and function in major microbial systems, including bacteria, fungi, protozoa, and algae. We highlight key similarities and differences that may aid in our understanding of how polyP impacts cell physiology at a molecular level.
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Affiliation(s)
- Alix Denoncourt
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, K1H 8M5, Canada.,Ottawa Institute of Systems Biology, Ottawa, K1H 8M5, Canada
| | - Michael Downey
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, K1H 8M5, Canada. .,Ottawa Institute of Systems Biology, Ottawa, K1H 8M5, Canada.
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7
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The IP 3 receptor and Ca 2+ signaling in trypanosomes. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2021; 1868:118947. [PMID: 33421534 DOI: 10.1016/j.bbamcr.2021.118947] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 12/11/2020] [Accepted: 12/14/2020] [Indexed: 11/23/2022]
Abstract
Trypanosoma cruzi, and the T. brucei group of parasites cause neglected diseases that affect millions of people around the world. These unicellular microorganisms have complex life cycles involving an insect vector and a mammalian host. Both groups of pathogens possess an inositol 1,4,5-trisphosphate (IP3)/diacylglycerol (DAG) signaling pathway, and an IP3 receptor, but with lineage-specific adaptations that make them different from their mammalian counterparts. The phospholipase C (PLC), which hydrolyzes phosphatidyl inositol 4,5-bisphosphate (PIP2) to IP3 is N-terminally myristoylated and palmitoylated. Acidocalcisomes, which are lysosome-related organelles rich in polyphosphate, are the main intracellular Ca2+ stores. The inositol 1,4,5-trisphosphate receptor (IP3R) localizes to acidocalcisomes instead of the endoplasmic reticulum. The trypanosome IP3R is stimulated by luminal phosphate and pyrophosphate, which are hydrolysis products of polyphosphate (polyP), and inhibited by tripolyphosphate (polyP3), which is the most abundant polyP in acidocalcisomes. Ca2+ signaling is important for host cell invasion and differentiation and to maintain cellular bioenergetics.
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8
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Asady B, Dick CF, Ehrenman K, Sahu T, Romano JD, Coppens I. A single Na+-Pi cotransporter in Toxoplasma plays key roles in phosphate import and control of parasite osmoregulation. PLoS Pathog 2021; 16:e1009067. [PMID: 33383579 PMCID: PMC7817038 DOI: 10.1371/journal.ppat.1009067] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 01/20/2021] [Accepted: 10/14/2020] [Indexed: 11/22/2022] Open
Abstract
Inorganic ions such as phosphate, are essential nutrients required for a broad spectrum of cellular functions and regulation. During infection, pathogens must obtain inorganic phosphate (Pi) from the host. Despite the essentiality of phosphate for all forms of life, how the intracellular parasite Toxoplasma gondii acquires Pi from the host cell is still unknown. In this study, we demonstrated that Toxoplasma actively internalizes exogenous Pi by exploiting a gradient of Na+ ions to drive Pi uptake across the plasma membrane. The Na+-dependent phosphate transport mechanism is electrogenic and functionally coupled to a cipargarmin sensitive Na+-H+-ATPase. Toxoplasma expresses one transmembrane Pi transporter harboring PHO4 binding domains that typify the PiT Family. This transporter named TgPiT, localizes to the plasma membrane, the inward buds of the endosomal organelles termed VAC, and many cytoplasmic vesicles. Upon Pi limitation in the medium, TgPiT is more abundant at the plasma membrane. We genetically ablated the PiT gene, and ΔTgPiT parasites are impaired in importing Pi and synthesizing polyphosphates. Interestingly, ΔTgPiT parasites accumulate 4-times more acidocalcisomes, storage organelles for phosphate molecules, as compared to parental parasites. In addition, these mutants have a reduced cell volume, enlarged VAC organelles, defects in calcium storage and a slightly alkaline pH. Overall, these mutants exhibit severe growth defects and have reduced acute virulence in mice. In survival mode, ΔTgPiT parasites upregulate several genes, including those encoding enzymes that cleave or transfer phosphate groups from phosphometabolites, transporters and ions exchangers localized to VAC or acidocalcisomes. Taken together, these findings point to a critical role of TgPiT for Pi supply for Toxoplasma and also for protection against osmotic stresses. Inorganic phosphate (Pi) is indispensable for the biosynthesis of key cellular components, and is involved in many metabolic and signaling pathways. Transport across the plasma membrane is the first step in the utilization of Pi. The import mechanism of Pi by the intracellular parasite Toxoplasma is unknown. We characterized a transmembrane, high-affinity Na+-Pi cotransporter, named TgPiT, expressed by the parasite at the plasma membrane for Pi uptake. Interestingly, TgPiT is also localized to inward buds of the endosomal VAC organelles and some cytoplasmic vesicles. Loss of TgPiT results in a severe reduction in Pi internalization and polyphosphate levels, but stimulation of the biogenesis of phosphate-enriched acidocalcisomes. ΔTgPiT parasites have a shrunken cell body, enlarged VAC organelles, poor release of stored calcium and a mildly alkaline pH, suggesting a role for TgPiT in the maintenance of overall ionic homeostasis. ΔTgPiT parasites are poorly infectious in vitro and in mice. The mutant appears to partially cope with the absence of TgPiT by up-regulating genes coding for ion transporters and enzymes catalyzing phosphate group transfer. Our data highlight a scenario in which the role of TgPiT in Pi and Na+ transport is functionally coupled with osmoregulation activities central to sustain Toxoplasma survival.
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Affiliation(s)
- Beejan Asady
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore Maryland, United States of America
| | - Claudia F. Dick
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore Maryland, United States of America
| | - Karen Ehrenman
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore Maryland, United States of America
| | - Tejram Sahu
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore Maryland, United States of America
| | - Julia D. Romano
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore Maryland, United States of America
| | - Isabelle Coppens
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore Maryland, United States of America
- * E-mail:
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9
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Wallnöfer EA, Thurner GC, Kremser C, Talasz H, Stollenwerk MM, Helbok A, Klammsteiner N, Albrecht-Schgoer K, Dietrich H, Jaschke W, Debbage P. Albumin-based nanoparticles as contrast medium for MRI: vascular imaging, tissue and cell interactions, and pharmacokinetics of second-generation nanoparticles. Histochem Cell Biol 2020; 155:19-73. [PMID: 33040183 DOI: 10.1007/s00418-020-01919-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/31/2020] [Indexed: 12/14/2022]
Abstract
This multidisciplinary study examined the pharmacokinetics of nanoparticles based on albumin-DTPA-gadolinium chelates, testing the hypothesis that these nanoparticles create a stronger vessel signal than conventional gadolinium-based contrast agents and exploring if they are safe for clinical use. Nanoparticles based on human serum albumin, bearing gadolinium and designed for use in magnetic resonance imaging, were used to generate magnet resonance images (MRI) of the vascular system in rats ("blood pool imaging"). At the low nanoparticle doses used for radionuclide imaging, nanoparticle-associated metals were cleared from the blood into the liver during the first 4 h after nanoparticle application. At the higher doses required for MRI, the liver became saturated and kidney and spleen acted as additional sinks for the metals, and accounted for most processing of the nanoparticles. The multiple components of the nanoparticles were cleared independently of one another. Albumin was detected in liver, spleen, and kidneys for up to 2 days after intravenous injection. Gadolinium was retained in the liver, kidneys, and spleen in significant concentrations for much longer. Gadolinium was present as significant fractions of initial dose for longer than 2 weeks after application, and gadolinium clearance was only complete after 6 weeks. Our analysis could not account quantitatively for the full dose of gadolinium that was applied, but numerous organs were found to contain gadolinium in the collagen of their connective tissues. Multiple lines of evidence indicated intracellular processing opening the DTPA chelates and leading to gadolinium long-term storage, in particular inside lysosomes. Turnover of the stored gadolinium was found to occur in soluble form in the kidneys, the liver, and the colon for up to 3 weeks after application. Gadolinium overload poses a significant hazard due to the high toxicity of free gadolinium ions. We discuss the relevance of our findings to gadolinium-deposition diseases.
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Affiliation(s)
- E A Wallnöfer
- Department of Radiology, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria
| | - G C Thurner
- Department of Radiology, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria
- Division of Histology and Embryology, Department of Anatomy, Histology and Embryology, Medical University of Innsbruck, Müllerstrasse 59, 6020, Innsbruck, Austria
| | - C Kremser
- Department of Radiology, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria
| | - H Talasz
- Division of Clinical Biochemistry, Biocenter, Medical University of Innsbruck, Innrain 80-82, 6020, Innsbruck, Austria
| | - M M Stollenwerk
- Faculty of Health and Society, Biomedical Laboratory Science, University Hospital MAS, Malmö University, 205 06, Malmö, Sweden
- Division of Histology and Embryology, Department of Anatomy, Histology and Embryology, Medical University of Innsbruck, Müllerstrasse 59, 6020, Innsbruck, Austria
| | - A Helbok
- Department of Nuclear Medicine, Innsbruck Medical University, Anichstrasse 35, 6020, Innsbruck, Austria
| | - N Klammsteiner
- Division of Histology and Embryology, Department of Anatomy, Histology and Embryology, Medical University of Innsbruck, Müllerstrasse 59, 6020, Innsbruck, Austria
| | - K Albrecht-Schgoer
- Department of Pharmaceutical Technology, Institute of Pharmacy, Leopold-Franzens-University Innsbruck, Innrain 80-82/IV, 6020, Innsbruck, Austria
- Institute of Cell Genetics, Department for Pharmacology and Genetics, Medical University of Innsbruck, Peter-Mayr-Strasse 1a, 6020, Innsbruck, Austria
| | - H Dietrich
- Central Laboratory Animal Facilities, Innsbruck Medical University, Peter-Mayr-Strasse 4a, 6020, Innsbruck, Austria
| | - W Jaschke
- Department of Radiology, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria
| | - P Debbage
- Division of Histology and Embryology, Department of Anatomy, Histology and Embryology, Medical University of Innsbruck, Müllerstrasse 59, 6020, Innsbruck, Austria.
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10
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Sanz-Luque E, Bhaya D, Grossman AR. Polyphosphate: A Multifunctional Metabolite in Cyanobacteria and Algae. FRONTIERS IN PLANT SCIENCE 2020; 11:938. [PMID: 32670331 PMCID: PMC7332688 DOI: 10.3389/fpls.2020.00938] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 06/09/2020] [Indexed: 05/19/2023]
Abstract
Polyphosphate (polyP), a polymer of orthophosphate (PO4 3-) of varying lengths, has been identified in all kingdoms of life. It can serve as a source of chemical bond energy (phosphoanhydride bond) that may have been used by biological systems prior to the evolution of ATP. Intracellular polyP is mainly stored as granules in specific vacuoles called acidocalcisomes, and its synthesis and accumulation appear to impact a myriad of cellular functions. It serves as a reservoir for inorganic PO4 3- and an energy source for fueling cellular metabolism, participates in maintaining adenylate and metal cation homeostasis, functions as a scaffold for sequestering cations, exhibits chaperone function, covalently binds to proteins to modify their activity, and enables normal acclimation of cells to stress conditions. PolyP also appears to have a role in symbiotic and parasitic associations, and in higher eukaryotes, low polyP levels seem to impact cancerous proliferation, apoptosis, procoagulant and proinflammatory responses and cause defects in TOR signaling. In this review, we discuss the metabolism, storage, and function of polyP in photosynthetic microbes, which mostly includes research on green algae and cyanobacteria. We focus on factors that impact polyP synthesis, specific enzymes required for its synthesis and degradation, sequestration of polyP in acidocalcisomes, its role in cellular energetics, acclimation processes, and metal homeostasis, and then transition to its potential applications for bioremediation and medical purposes.
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Affiliation(s)
- Emanuel Sanz-Luque
- Department of Plant Biology, The Carnegie Institution for Science, Stanford, CA, United States
- Department of Biochemistry and Molecular Biology, University of Cordoba, Cordoba, Spain
| | - Devaki Bhaya
- Department of Plant Biology, The Carnegie Institution for Science, Stanford, CA, United States
| | - Arthur R. Grossman
- Department of Plant Biology, The Carnegie Institution for Science, Stanford, CA, United States
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11
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Johansson NG, Turku A, Vidilaseris K, Dreano L, Khattab A, Ayuso Pérez D, Wilkinson A, Zhang Y, Tamminen M, Grazhdankin E, Kiriazis A, Fishwick CWG, Meri S, Yli-Kauhaluoma J, Goldman A, Boije af Gennäs G, Xhaard H. Discovery of Membrane-Bound Pyrophosphatase Inhibitors Derived from an Isoxazole Fragment. ACS Med Chem Lett 2020; 11:605-610. [PMID: 32292570 PMCID: PMC7153278 DOI: 10.1021/acsmedchemlett.9b00537] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 02/10/2020] [Indexed: 12/21/2022] Open
Abstract
![]()
Membrane-bound
pyrophosphatases (mPPases) regulate energy homeostasis
in pathogenic protozoan parasites and lack human homologues, which
makes them promising targets in e.g. malaria. Yet
only few nonphosphorus inhibitors have been reported so far. Here,
we explore an isoxazole fragment hit, leading to the discovery of
small mPPase inhibitors with 6–10 μM IC50 values
in the Thermotoga maritima test system. Promisingly,
the compounds retained activity against Plasmodium falciparum mPPase in membranes and inhibited parasite growth.
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Affiliation(s)
- Niklas G. Johansson
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56 (Viikinkaari 5 E), FI-00014 Helsinki, Finland
| | - Ainoleena Turku
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56 (Viikinkaari 5 E), FI-00014 Helsinki, Finland
| | - Keni Vidilaseris
- Department of Biosciences, Division of Biochemistry, University of Helsinki, P.O. Box 56
(Viikinkaari 9), FI-00014 Helsinki, Finland
| | - Loïc Dreano
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56 (Viikinkaari 5 E), FI-00014 Helsinki, Finland
| | - Ayman Khattab
- Malaria Research Laboratory, Translational Immunology Research Program, Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki, P.O. Box 21
(Haartmaninkatu 3), FI-00014 Helsinki, Finland
| | - Daniel Ayuso Pérez
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56 (Viikinkaari 5 E), FI-00014 Helsinki, Finland
| | - Aaron Wilkinson
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds LS2 9JT, United Kingdom
| | - Yuezhou Zhang
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56 (Viikinkaari 5 E), FI-00014 Helsinki, Finland
| | - Matti Tamminen
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56 (Viikinkaari 5 E), FI-00014 Helsinki, Finland
| | - Evgeni Grazhdankin
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56 (Viikinkaari 5 E), FI-00014 Helsinki, Finland
| | - Alexandros Kiriazis
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56 (Viikinkaari 5 E), FI-00014 Helsinki, Finland
| | - Colin W. G. Fishwick
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds LS2 9JT, United Kingdom
| | - Seppo Meri
- Malaria Research Laboratory, Translational Immunology Research Program, Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki, P.O. Box 21
(Haartmaninkatu 3), FI-00014 Helsinki, Finland
| | - Jari Yli-Kauhaluoma
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56 (Viikinkaari 5 E), FI-00014 Helsinki, Finland
| | - Adrian Goldman
- Department of Biosciences, Division of Biochemistry, University of Helsinki, P.O. Box 56
(Viikinkaari 9), FI-00014 Helsinki, Finland
- School of Biomedical Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Clarendon Way, Leeds LS2 9JT, United Kingdom
| | - Gustav Boije af Gennäs
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56 (Viikinkaari 5 E), FI-00014 Helsinki, Finland
| | - Henri Xhaard
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56 (Viikinkaari 5 E), FI-00014 Helsinki, Finland
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12
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Mirra B, Carvalho K, Curitiba B, Ribeiro L, Moraes J, da Silva JR, Costa EP, da Fonseca RN, Campos E. Inorganic pyrophosphatase from the red flour beetle (Tribolium castaneum) modulates mitochondrial polyphosphate metabolism. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2019; 102:e21606. [PMID: 31498484 DOI: 10.1002/arch.21606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 06/11/2019] [Accepted: 07/08/2019] [Indexed: 06/10/2023]
Abstract
Polyphosphates (polyPs) have been found in all cell types examined to date and play diverse roles, depending on the cell type. In eukaryotic organisms, polyPs have been mainly investigated in mammalian cells, with few studies on insects. In this study, we investigated mitochondrial polyphosphate metabolism in the red flour beetle, Tribolium castaneum. Substrate specificity for different chain lengths demonstrated the presence of two exopolyphosphatase isoforms in mitochondria. T. castaneum mitochondrial polyP levels decreased after injection with soluble pyrophosphatase (Tc-sPPase) dsRNA, while the membrane exopolyphosphate activity increased. Mitochondrial respiration modulated exopolyphosphatase activity only in wild-type beetles. Tripolyphosphate was able to increase the F-ATPase activity in wild-type and Tc-sPPase RNAi beetles. We suggest that inorganic pyrophosphatase modulates polyphosphate metabolism in mitochondria and affects the link between mitochondrial activity and polyphosphate metabolism in T. castaneum.
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Affiliation(s)
- Bianca Mirra
- Laboratório Integrado de Bioquímica - Hatisaburo Masuda, Instituto de Biodiversidade e Sustentabilidade, NUPEM/UFRJ, Macaé, Brazil
| | - Klébea Carvalho
- Laboratório Integrado de Bioquímica - Hatisaburo Masuda, Instituto de Biodiversidade e Sustentabilidade, NUPEM/UFRJ, Macaé, Brazil
| | - Bianca Curitiba
- Laboratório Integrado de Bioquímica - Hatisaburo Masuda, Instituto de Biodiversidade e Sustentabilidade, NUPEM/UFRJ, Macaé, Brazil
| | - Lupis Ribeiro
- Laboratório Integrado de Bioquímica - Hatisaburo Masuda, Instituto de Biodiversidade e Sustentabilidade, NUPEM/UFRJ, Macaé, Brazil
| | - Jorge Moraes
- Laboratório Integrado de Bioquímica - Hatisaburo Masuda, Instituto de Biodiversidade e Sustentabilidade, NUPEM/UFRJ, Macaé, Brazil
- Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular, UFRJ, Rio de Janeiro, Brazil
| | - José R da Silva
- Laboratório Integrado de Bioquímica - Hatisaburo Masuda, Instituto de Biodiversidade e Sustentabilidade, NUPEM/UFRJ, Macaé, Brazil
- Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular, UFRJ, Rio de Janeiro, Brazil
| | - Evenilton P Costa
- Laboratório Integrado de Bioquímica - Hatisaburo Masuda, Instituto de Biodiversidade e Sustentabilidade, NUPEM/UFRJ, Macaé, Brazil
| | - Rodrigo N da Fonseca
- Laboratório Integrado de Bioquímica - Hatisaburo Masuda, Instituto de Biodiversidade e Sustentabilidade, NUPEM/UFRJ, Macaé, Brazil
- Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular, UFRJ, Rio de Janeiro, Brazil
| | - Eldo Campos
- Laboratório Integrado de Bioquímica - Hatisaburo Masuda, Instituto de Biodiversidade e Sustentabilidade, NUPEM/UFRJ, Macaé, Brazil
- Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular, UFRJ, Rio de Janeiro, Brazil
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13
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Matange N. Deorphanizing NUDIX hydrolases from Trypanosoma: tantalizing links with metabolic regulation and stress tolerance. Biosci Rep 2019; 39:BSR20191369. [PMID: 31160481 PMCID: PMC6616042 DOI: 10.1042/bsr20191369] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 06/01/2019] [Accepted: 06/03/2019] [Indexed: 12/15/2022] Open
Abstract
An explosion of sequence information in the genomics era has thrown up thousands of protein sequences without functional assignment. Though our ability to predict function based on sequence alone is improving steadily, we still have a long way to go. Proteins with common evolutionary origins carry telling sequence signatures, which ought to reveal their biological roles. These sequence signatures have allowed us to classify proteins into families with similar structures, and possibly, functions. Yet, evolution is a perpetual tinkerer, and hence, sequence signatures alone have proved inadequate in understanding the physiological activities of proteins. One such enigmatic family of enzymes is the NUDIX ( nu cleoside di phosphate linked to a moiety X ) hydrolase family that has over 80000 members from all branches of the tree of life. Though MutT, the founding member of this family, was identified in 1954, we are only now beginning to understand the diversity of substrates and biological roles that these enzymes demonstrate. In a recent article by Cordeiro et al. in Bioscience Reports [Biosci. Rep. (2019)], two members of this protein family from the human pathogen Trypanosoma brucei were deorphanized as being polyphosphate hydrolases. The authors show that of the five NUDIX hydrolases coded by the T. brucei genomes, TbNH2 and TbNH4, show in vitro hydrolytic activity against inorganic polyphosphate. Through classical biochemistry and immunostaining microscopy, differences in their substrate specificities and sub-cellular localization were revealed. These new data provide a compelling direction to the study of Trypanosome stress biology as well as our understanding of the NUDIX enzyme family.
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Affiliation(s)
- Nishad Matange
- Department of Biology, Indian Institute of Science Education and Research (IISER), Pune, India
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14
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Cordeiro CD, Ahmed MA, Windle B, Docampo R. NUDIX hydrolases with inorganic polyphosphate exo- and endopolyphosphatase activities in the glycosome, cytosol and nucleus of Trypanosoma brucei. Biosci Rep 2019; 39:BSR20190894. [PMID: 31043451 PMCID: PMC6522730 DOI: 10.1042/bsr20190894] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Revised: 04/26/2019] [Accepted: 04/30/2019] [Indexed: 12/11/2022] Open
Abstract
Trypanosoma brucei, a protist parasite that causes African trypanosomiasis or sleeping sickness, relies mainly on glycolysis for ATP production when in its mammalian host. Glycolysis occurs within a peroxisome-like organelle named the glycosome. Previous work from our laboratory reported the presence of significant amounts of inorganic polyphosphate (polyP), a polymer of three to hundreds of orthophosphate units, in the glycosomes and nucleoli of T. brucei In this work, we identified and characterized the activity of two Nudix hydrolases (NHs), T. brucei Nudix hydrolase (TbNH) 2 and TbNH4, one located in the glycosomes and the other in the cytosol and nucleus, respectively, which can degrade polyP. We found that TbNH2 is an exopolyphosphatase with higher activity on short chain polyP, while TbNH4 is an endo- and exopolyphosphatase that has similar activity on polyP of various chain sizes. Both enzymes have higher activity at around pH 8.0. We also found that only TbNH2 can dephosphorylate ATP and ADP but with lower affinity than for polyP. Our results suggest that NHs can participate in polyP homeostasis and therefore may help control polyP levels in glycosomes, cytosol and nuclei of T. brucei.
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Affiliation(s)
- Ciro D Cordeiro
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, U.S.A
| | - Michael A Ahmed
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - Brian Windle
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - Roberto Docampo
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, U.S.A
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15
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Potapenko E, Negrão NW, Huang G, Docampo R. The acidocalcisome inositol-1,4,5-trisphosphate receptor of Trypanosoma brucei is stimulated by luminal polyphosphate hydrolysis products. J Biol Chem 2019; 294:10628-10637. [PMID: 31138655 DOI: 10.1074/jbc.ra119.007906] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 05/27/2019] [Indexed: 12/21/2022] Open
Abstract
Acidocalcisomes are acidic calcium stores rich in polyphosphate (polyP) and are present in trypanosomes and also in a diverse range of other organisms. Ca2+ is released from these organelles through a channel, inositol 1,4,5-trisphosphate receptor (TbIP3R), which is essential for growth and infectivity of the parasite Trypanosoma brucei However, the mechanism by which TbIP3R controls Ca2+ release is unclear. In this work, we expressed TbIP3R in a chicken B lymphocyte cell line in which the genes for all three vertebrate IP3Rs were stably ablated (DT40-3KO). We show that IP3-mediated Ca2+ release depends on Ca2+ but not on ATP concentration and is inhibited by heparin, caffeine, and 2-aminomethoxydiphenyl borate (2-APB). Excised patch clamp recordings from nuclear membranes of DT40 cells expressing only TbIP3R disclosed that luminal inorganic orthophosphate (Pi) or pyrophosphate (PPi), and neutral or alkaline pH can stimulate IP3-generated currents. In contrast, polyP or acidic pH did not induce these currents, and nuclear membranes obtained from cells expressing rat IP3R were unresponsive to polyP or its hydrolysis products. Our results are consistent with the notion that polyP hydrolysis products within acidocalcisomes or alkalinization of their luminal pH activate TbIP3R and Ca2+ release. We conclude that TbIP3R is well-adapted to its role as the major Ca2+ release channel of acidocalcisomes in T. brucei.
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Affiliation(s)
| | - Núria W Negrão
- From the Center for Tropical and Emerging Global Diseases and.,Department of Cellular Biology, University of Georgia, Athens, Georgia 30602
| | - Guozhong Huang
- From the Center for Tropical and Emerging Global Diseases and
| | - Roberto Docampo
- From the Center for Tropical and Emerging Global Diseases and .,Department of Cellular Biology, University of Georgia, Athens, Georgia 30602
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16
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An J, Cho J. Catalytic properties of wheat phytase that favorably degrades long-chain inorganic polyphosphate. ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 2019; 33:127-131. [PMID: 31208182 PMCID: PMC6946983 DOI: 10.5713/ajas.19.0047] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 04/29/2019] [Indexed: 02/06/2023]
Abstract
Objective This study was conducted to determine catalytic properties of wheat phytase with exopolyphosphatase activity toward medium-chain and long-chain inorganic polyphosphate (polyP) substrates for comparative purpose. Methods Exopolyphosphatase assay of wheat phytase toward polyP75 (medium-chain polyP with average 75 phosphate residues) and polyP1150 (long-chain polyP with average 1150 phosphate residues) was performed at pH 5.2 and pH 7.5. Its activity toward these substrates was investigated in the presence of Mg2+, Ni2+, Co2+, Mn2+, or ethylenediaminetetraacetic acid (EDTA). Michaelis constant (Km) and maximum reaction velocity (Vmax) were determined from Lineweaver-Burk plot with polyP75 or polyP1150. Monophosphate esterase activity toward p-nitrophenyl phosphate (pNPP) was assayed in the presence of polyP75 or polyP1150. Results Wheat phytase dephosphorylated polyP75 and polyP1150 at pH 7.5 more effectively than that at pH 5.2. Its exopolyphosphatase activity toward polyP75 at pH 5.2 was 1.4-fold higher than that toward polyP1150 whereas its activity toward polyP75 at pH 7.5 was 1.4-fold lower than that toward polyP1150. Regarding enzyme kinetics, Km for polyP75 was 1.4-fold lower than that for polyP1150 while Vmax for polyP1150 was 2-fold higher than that for polyP75. The presence of Mg2+, Ni2+, Co2+, Mn2+, or EDTA (1 or 5 mM) exhibited no inhibitory effect on its activity toward polyP75. Its activity toward polyP1150 was inhibited by 1 mM of Ni2+ or Co2+ and 5 mM of Ni2+, Co2+, or Mg2+. Ni2+ inhibited its activity toward polyP1150 the most strongly among tested additives. Both polyP75 and polyP1150 inhibited the monophosphate esterase activity of wheat phytase toward pNPP in a dose-dependent manner. Conclusion Wheat phytase with an unexpected exopolyphosphatase activity has potential as a therapeutic tool and a next-generational feed additive for controlling long-chain polyP-induced inappropriate inflammation from Campylobacter jejuni and Salmonella typhimurium infection in public health and animal husbandry.
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Affiliation(s)
- Jeongmin An
- Department of Animal Science and Technology, Konkuk University, Seoul 05029, Korea
| | - Jaiesoon Cho
- Department of Animal Science and Technology, Konkuk University, Seoul 05029, Korea
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17
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Vidilaseris K, Kiriazis A, Turku A, Khattab A, Johansson NG, Leino TO, Kiuru PS, Boije af Gennäs G, Meri S, Yli-Kauhaluoma J, Xhaard H, Goldman A. Asymmetry in catalysis by Thermotoga maritima membrane-bound pyrophosphatase demonstrated by a nonphosphorus allosteric inhibitor. SCIENCE ADVANCES 2019; 5:eaav7574. [PMID: 31131322 PMCID: PMC6530997 DOI: 10.1126/sciadv.aav7574] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 04/16/2019] [Indexed: 06/09/2023]
Abstract
Membrane-bound pyrophosphatases are homodimeric integral membrane proteins that hydrolyze pyrophosphate into orthophosphates, coupled to the active transport of protons or sodium ions across membranes. They are important in the life cycle of bacteria, archaea, plants, and parasitic protists, but no homologous proteins exist in vertebrates, making them a promising drug target. Here, we report the first nonphosphorus allosteric inhibitor of the thermophilic bacterium Thermotoga maritima membrane-bound pyrophosphatase and its bound structure together with the substrate analog imidodiphosphate. The unit cell contains two protein homodimers, each binding a single inhibitor dimer near the exit channel, creating a hydrophobic clamp that inhibits the movement of β-strand 1-2 during pumping, and thus prevents the hydrophobic gate from opening. This asymmetry of inhibitor binding with respect to each homodimer provides the first clear structural demonstration of asymmetry in the catalytic cycle of membrane-bound pyrophosphatases.
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Affiliation(s)
- Keni Vidilaseris
- Research Program in Molecular and Integrative Biosciences, University of Helsinki, Helsinki, Finland
| | - Alexandros Kiriazis
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Ainoleena Turku
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Ayman Khattab
- Malaria Research Laboratory, Immunobiology Research Program, Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki, Helsinki, Finland
| | - Niklas G. Johansson
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Teppo O. Leino
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Paula S. Kiuru
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Gustav Boije af Gennäs
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Seppo Meri
- Malaria Research Laboratory, Immunobiology Research Program, Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki, Helsinki, Finland
| | - Jari Yli-Kauhaluoma
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Henri Xhaard
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Adrian Goldman
- Research Program in Molecular and Integrative Biosciences, University of Helsinki, Helsinki, Finland
- School of Biomedical Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK
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18
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PAS domain-containing phosphoglycerate kinase deficiency in Leishmania major results in increased autophagosome formation and cell death. Biochem J 2019; 476:1303-1321. [PMID: 30988012 DOI: 10.1042/bcj20190041] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 04/08/2019] [Accepted: 04/12/2019] [Indexed: 11/17/2022]
Abstract
Per-Arnt-Sim (PAS) domains are structurally conserved and present in numerous proteins throughout all branches of the phylogenetic tree. Although PAS domain-containing proteins are major players for the adaptation to environmental stimuli in both prokaryotic and eukaryotic organisms, these types of proteins are still uncharacterized in the trypanosomatid parasites, Trypanosome and Leishmania In addition, PAS-containing phosphoglycerate kinase (PGK) protein is uncharacterized in the literature. Here, we report a PAS domain-containing PGK (LmPAS-PGK) in the unicellular pathogen Leishmania The modeled structure of N-terminal of this protein exhibits four antiparallel β sheets centrally flanked by α helices, which is similar to the characteristic signature of PAS domain. Activity measurements suggest that acidic pH can directly stimulate PGK activity. Localization studies demonstrate that the protein is highly enriched in the glycosome and its presence can also be seen in the lysosome. Gene knockout, overexpression and complement studies suggest that LmPAS-PGK plays a fundamental role in cell survival through autophagy. Furthermore, the knockout cells display a marked decrease in virulence when host macrophage and BALB/c mice were infected with them. Our work begins to clarify how acidic pH-dependent ATP generation by PGK is likely to function in cellular adaptability of Leishmania.
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19
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Pyrophosphate Stimulates the Phosphate-Sodium Symporter of Trypanosoma brucei Acidocalcisomes and Saccharomyces cerevisiae Vacuoles. mSphere 2019; 4:4/2/e00045-19. [PMID: 30944211 PMCID: PMC6449605 DOI: 10.1128/msphere.00045-19] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Acidocalcisomes, first described in trypanosomes and known to be present in a variety of cells, have similarities with S. cerevisiae vacuoles in their structure and composition. Both organelles share a Na+/Pi symporter involved in Pi release to the cytosol, where it is needed for biosynthetic reactions. Here we show that PPi, at physiological cytosolic concentrations, stimulates the symporter expressed in either Xenopus oocytes or yeast vacuoles via its SPX domain, revealing a signaling role of this molecule. Inorganic pyrophosphate (PPi) is a by-product of biosynthetic reactions and has bioenergetic and regulatory roles in a variety of cells. Here we show that PPi and other pyrophosphate-containing compounds, including polyphosphate (polyP), can stimulate sodium-dependent depolarization of the membrane potential and Pi conductance in Xenopus oocytes expressing a Saccharomyces cerevisiae or Trypanosoma brucei Na+/Pi symporter. PPi is not taken up by Xenopus oocytes, and deletion of the TbPho91 SPX domain abolished its depolarizing effect. PPi generated outward currents in Na+/Pi-loaded giant vacuoles prepared from wild-type or pho91Δ yeast strains expressing TbPHO91 but not from the pho91Δ strains. Our results suggest that PPi, at physiological concentrations, can function as a signaling molecule releasing Pi from S. cerevisiae vacuoles and T. brucei acidocalcisomes. IMPORTANCE Acidocalcisomes, first described in trypanosomes and known to be present in a variety of cells, have similarities with S. cerevisiae vacuoles in their structure and composition. Both organelles share a Na+/Pi symporter involved in Pi release to the cytosol, where it is needed for biosynthetic reactions. Here we show that PPi, at physiological cytosolic concentrations, stimulates the symporter expressed in either Xenopus oocytes or yeast vacuoles via its SPX domain, revealing a signaling role of this molecule.
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20
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Grillo-Puertas M, Delaporte-Quintana P, Pedraza RO, Rapisarda VA. Intracellular Polyphosphate Levels in Gluconacetobacter diazotrophicus Affect Tolerance to Abiotic Stressors and Biofilm Formation. Microbes Environ 2018; 33:440-445. [PMID: 30404971 PMCID: PMC6307995 DOI: 10.1264/jsme2.me18044] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Gluconacetobacter diazotrophicus is a plant growth-promoting bacterium that is used as a bioinoculant. Phosphate (Pi) modulates intracellular polyphosphate (polyP) levels in Escherichia coli, affecting cellular fitness and biofilm formation capacity. It currently remains unclear whether environmental Pi modulates polyP levels in G. diazotrophicus to enhance fitness in view of its technological applications. In high Pi media, cells accumulated polyP and degraded it, thereby improving survival, tolerance to environmental stressors, biofilm formation capacity on abiotic and biotic surfaces, and competence as a growth promoter of strawberry plants. The present results support the importance of Pi and intracellular polyP as signals involved in the survival of G. diazotrophicus.
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Affiliation(s)
- Mariana Grillo-Puertas
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET-UNT, and Instituto de Química Biológica, "Dr. Bernabé Bloj", Facultad de Bioquímica, Química y Farmacia, UNT. San Miguel de Tucumán
| | | | | | - Viviana Andrea Rapisarda
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET-UNT, and Instituto de Química Biológica, "Dr. Bernabé Bloj", Facultad de Bioquímica, Química y Farmacia, UNT. San Miguel de Tucumán
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21
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Negreiros RS, Lander N, Huang G, Cordeiro CD, Smith SA, Morrissey JH, Docampo R. Inorganic polyphosphate interacts with nucleolar and glycosomal proteins in trypanosomatids. Mol Microbiol 2018; 110:973-994. [PMID: 30230089 DOI: 10.1111/mmi.14131] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/14/2018] [Indexed: 12/11/2022]
Abstract
Inorganic polyphosphate (polyP) is a polymer of three to hundreds of phosphate units bound by high-energy phosphoanhydride bonds and present from bacteria to humans. Most polyP in trypanosomatids is concentrated in acidocalcisomes, acidic calcium stores that possess a number of pumps, exchangers, and channels, and are important for their survival. In this work, using polyP as bait we identified > 25 putative protein targets in cell lysates of both Trypanosoma cruzi and Trypanosoma brucei. Gene ontology analysis of the binding partners found a significant over-representation of nucleolar and glycosomal proteins. Using the polyphosphate-binding domain (PPBD) of Escherichia coli exopolyphosphatase (PPX), we localized long-chain polyP to the nucleoli and glycosomes of trypanosomes. A competitive assay based on the pre-incubation of PPBD with exogenous polyP and subsequent immunofluorescence assay of procyclic forms (PCF) of T. brucei showed polyP concentration-dependent and chain length-dependent decrease in the fluorescence signal. Subcellular fractionation experiments confirmed the presence of polyP in glycosomes of T. brucei PCF. Targeting of yeast PPX to the glycosomes of PCF resulted in polyP hydrolysis, alteration in their glycolytic flux and increase in their susceptibility to oxidative stress.
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Affiliation(s)
- Raquel S Negreiros
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, 30602, USA
| | - Noelia Lander
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, 30602, USA.,Department of Cellular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Guozhong Huang
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, 30602, USA
| | - Ciro D Cordeiro
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, 30602, USA.,Department of Cellular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Stephanie A Smith
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - James H Morrissey
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Roberto Docampo
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, 30602, USA.,Department of Cellular Biology, University of Georgia, Athens, GA, 30602, USA
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22
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Potapenko E, Cordeiro CD, Huang G, Storey M, Wittwer C, Dutta AK, Jessen HJ, Starai VJ, Docampo R. 5-Diphosphoinositol pentakisphosphate (5-IP 7) regulates phosphate release from acidocalcisomes and yeast vacuoles. J Biol Chem 2018; 293:19101-19112. [PMID: 30315104 DOI: 10.1074/jbc.ra118.005884] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Revised: 10/10/2018] [Indexed: 12/21/2022] Open
Abstract
Acidocalcisomes of Trypanosoma brucei and the acidocalcisome-like vacuoles of Saccharomyces cerevisiae are acidic calcium compartments that store polyphosphate (polyP). Both organelles possess a phosphate-sodium symporter (TbPho91 and Pho91p in T. brucei and yeast, respectively), but the roles of these transporters in growth and orthophosphate (Pi) transport are unclear. We found here that Tbpho91 -/- trypanosomes have a lower growth rate under phosphate starvation and contain larger acidocalcisomes that have increased Pi content. Heterologous expression of TbPHO91 in Xenopus oocytes followed by two-electrode voltage clamp recordings disclosed that myo-inositol polyphosphates stimulate both sodium-dependent depolarization of the oocyte membrane potential and Pi conductance. Deletion of the SPX domain in TbPho91 abolished this stimulation. Inositol pyrophosphates such as 5-diphosphoinositol pentakisphosphate generated outward currents in Na+/Pi-loaded giant vacuoles prepared from WT or from TbPHO91-expressing pho91Δ strains but not from the pho91Δ yeast strains or from the pho91Δ strains expressing PHO91 or TbPHO91 with mutated SPX domains. Our results indicate that TbPho91 and Pho91p are responsible for vacuolar Pi and Na+ efflux and that myo-inositol polyphosphates stimulate the Na+/Pi symporter activities through their SPX domains.
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Affiliation(s)
- Evgeniy Potapenko
- From the Center for Tropical and Emerging Global Diseases and.,the Departments of Cellular Biology and
| | - Ciro D Cordeiro
- From the Center for Tropical and Emerging Global Diseases and.,the Departments of Cellular Biology and
| | - Guozhong Huang
- From the Center for Tropical and Emerging Global Diseases and
| | - Melissa Storey
- From the Center for Tropical and Emerging Global Diseases and
| | - Christopher Wittwer
- the Department of Chemistry and Pharmacy, University of Freiburg, 79098 Freiburg, Germany
| | - Amit K Dutta
- the Department of Chemistry and Pharmacy, University of Freiburg, 79098 Freiburg, Germany
| | - Henning J Jessen
- the Department of Chemistry and Pharmacy, University of Freiburg, 79098 Freiburg, Germany
| | - Vincent J Starai
- Microbiology and Infectious Diseases, University of Georgia, Athens, Georgia 30602 and
| | - Roberto Docampo
- From the Center for Tropical and Emerging Global Diseases and .,the Departments of Cellular Biology and
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23
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Kohl K, Zangger H, Rossi M, Isorce N, Lye LF, Owens KL, Beverley SM, Mayer A, Fasel N. Importance of polyphosphate in the Leishmania life cycle. MICROBIAL CELL 2018; 5:371-384. [PMID: 30175107 PMCID: PMC6116282 DOI: 10.15698/mic2018.08.642] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Protozoan parasites contain negatively charged polymers of a few up to several hundreds of phosphate residues. In other organisms, these poly-phosphate (polyP) chains serve as an energy source and phosphate reservoir, and have been implicated in adaptation to stress and virulence of pathogenic organisms. In this study, we confirmed first that the polyP polymerase vacuolar transporter chaperone 4 (VTC4) is responsible for polyP synthesis in Leishmania parasites. During Leishmaniain vitro culture, polyP is accumulated in logarithmic growth phase and subsequently consumed once stationary phase is reached. However, polyP is not essential since VTC4-deficient (vtc4-) Leishmania proliferated normally in culture and differentiated into infective metacyclic parasites and into intracellular and axenic amastigotes. In in vivo mouse infections, L. majorVTC4 knockout showed a delay in lesion formation but ultimately gave rise to strong pathology, although we were unable to restore virulence by complementation to confirm this phenotype. Knockdown of VTC4 did not alter the course of L. guyanensis infections in mice, suggesting that polyP was not required for infection, or that very low levels of it suffice for lesion development. At higher temperatures, Leishmania promastigotes highly consumed polyP, and both knockdown or deletion of VTC4 diminished parasite survival. Thus, although polyP was not essential in the life cycle of the parasite, our data suggests a role for polyP in increasing parasite survival at higher temperatures, a situation faced by the parasite when transmitted to humans.
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Affiliation(s)
- Kid Kohl
- Department of Biochemistry, University of Lausanne, Epalinges, Switzerland
| | - Haroun Zangger
- Department of Biochemistry, University of Lausanne, Epalinges, Switzerland
| | - Matteo Rossi
- Department of Biochemistry, University of Lausanne, Epalinges, Switzerland
| | - Nathalie Isorce
- Department of Biochemistry, University of Lausanne, Epalinges, Switzerland
| | - Lon-Fye Lye
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Katherine L Owens
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Stephen M Beverley
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Andreas Mayer
- Department of Biochemistry, University of Lausanne, Epalinges, Switzerland
| | - Nicolas Fasel
- Department of Biochemistry, University of Lausanne, Epalinges, Switzerland
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24
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The Uptake and Metabolism of Amino Acids, and Their Unique Role in the Biology of Pathogenic Trypanosomatids. Pathogens 2018; 7:pathogens7020036. [PMID: 29614775 PMCID: PMC6027508 DOI: 10.3390/pathogens7020036] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 03/28/2018] [Accepted: 03/29/2018] [Indexed: 01/24/2023] Open
Abstract
Trypanosoma brucei, as well as Trypanosoma cruzi and more than 20 species of the genus Leishmania, form a group of flagellated protists that threaten human health. These organisms are transmitted by insects that, together with mammals, are their natural hosts. This implies that during their life cycles each of them faces environments with different physical, chemical, biochemical, and biological characteristics. In this work we review how amino acids are obtained from such environments, how they are metabolized, and how they and some of their intermediate metabolites are used as a survival toolbox to cope with the different conditions in which these parasites should establish the infections in the insects and mammalian hosts.
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25
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Cruz CS, Costa EP, Machado JA, Silva JN, Romeiro NC, Moraes J, Silva JR, Fonseca RN, Vaz IS, Logullo C, Campos E. A soluble inorganic pyrophosphatase from the cattle tick Rhipicephalus microplus capable of hydrolysing polyphosphates. INSECT MOLECULAR BIOLOGY 2018; 27:260-267. [PMID: 29271528 DOI: 10.1111/imb.12369] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Polyphosphates have been found in all cell types examined to date and play diverse roles depending on the cell type. In eukaryotic organisms, polyphosphates have been investigated mainly in mammalian cells, and only a few studies have addressed arthropods. Pyrophosphatases have been shown to regulate polyphosphate metabolism. However, these studies were restricted to trypanosomatids. Here we focus on the tick Rhipicephalus microplus, a haematophagous ectoparasite that is highly harmful to cattle. We produced a recombinant R. microplus pyrophosphatase (rRmPPase) with the aim of investigating its kinetic parameters using polyphosphates as substrate. Molecular docking assays of RmPPase with polyphosphates were also carried out. The kinetic and Hill coefficient parameters indicated that rRmPPase has a greater affinity, higher catalytic efficiency and increased cooperativity for sodium phosphate glass type 15 (polyP15 ) than for sodium tripolyphosphate (polyP3 ). Through molecular docking, we found that polyP3 binds close to the Mg2+ atoms in the catalytic region of the protein, participating in their coordination network, whereas polyP15 interactions involve negatively charged phosphate groups and basic amino acid residues, such as Lys56, Arg58 and Lys193; polyP15 has a more favourable theoretical binding affinity than polyP3 , thus supporting the kinetic data. This study shows, for the first time in arthropods, a pyrophosphatase with polyphosphatase activity, suggesting its participation in polyphosphate metabolism.
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Affiliation(s)
- C S Cruz
- Laboratório Integrado de Bioquímica - Hatisaburo Masuda, UFRJ, NUPEM, São José do Barreto, Macaé, Rio de Janeiro, Brazil
| | - E P Costa
- Laboratório de Química e Função de Proteínas e Peptídeos and Unidade de Experimentação Animal - CBB - UENF, Horto, Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - J A Machado
- Laboratório de Química e Função de Proteínas e Peptídeos and Unidade de Experimentação Animal - CBB - UENF, Horto, Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - J N Silva
- Laboratório de Química e Função de Proteínas e Peptídeos and Unidade de Experimentação Animal - CBB - UENF, Horto, Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - N C Romeiro
- Laboratório de Química e Função de Proteínas e Peptídeos and Unidade de Experimentação Animal - CBB - UENF, Horto, Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - J Moraes
- Laboratório Integrado de Bioquímica - Hatisaburo Masuda, UFRJ, NUPEM, São José do Barreto, Macaé, Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular, Rio de Janeiro, Brazil
| | - J R Silva
- Laboratório Integrado de Bioquímica - Hatisaburo Masuda, UFRJ, NUPEM, São José do Barreto, Macaé, Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular, Rio de Janeiro, Brazil
| | - R N Fonseca
- Laboratório Integrado de Bioquímica - Hatisaburo Masuda, UFRJ, NUPEM, São José do Barreto, Macaé, Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular, Rio de Janeiro, Brazil
| | - I S Vaz
- Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular, Rio de Janeiro, Brazil
- Centro de Biotecnologia e Faculdade de Veterinária, UFRGS, Porto Alegre, Rio Grande do Sul, Brazil
| | - C Logullo
- Laboratório de Química e Função de Proteínas e Peptídeos and Unidade de Experimentação Animal - CBB - UENF, Horto, Campos dos Goytacazes, Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular, Rio de Janeiro, Brazil
| | - E Campos
- Laboratório Integrado de Bioquímica - Hatisaburo Masuda, UFRJ, NUPEM, São José do Barreto, Macaé, Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular, Rio de Janeiro, Brazil
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26
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Identification of a novel PYP-1 gene in Sarcoptes scabiei and its potential as a serodiagnostic candidate by indirect-ELISA. Parasitology 2017; 145:752-761. [PMID: 29113603 DOI: 10.1017/s0031182017001780] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Scabies is a parasitic disease caused by the ectoparasite Sarcoptes scabiei, affecting different mammalian species, including rabbits, worldwide. In the present study, we cloned and expressed a novel inorganic pyrophosphatase, Ssc-PYP-1, from S. scabiei var. cuniculi. Immunofluorescence staining showed that native Ssc-PYP-1 was localized in the tegument around the mouthparts and the entire legs, as well as in the cuticle of the mites. Interestingly, obvious staining was also observed on the fecal pellets of mites and in the integument of the mites. Based on its good immunoreactivity, an indirect enzyme-linked immunosorbent assay (ELISA) using recombinant Ssc-PYP-1 (rSsc-PYP-1) as the capture antigen was developed to diagnose sarcoptic mange in naturally infected rabbits; the assay had a sensitivity of 92·0% and specificity of 93·6%. Finally, using the rSsc-PYP-1-ELISA, the Ssc-PYP-1 antibody from 10 experimentally infected rabbits could be detected from 1 week post-infection. This is the first report of S. scabiei inorganic pyrophosphatase and the protein could serve as a potential serodiagnostic candidate for sarcoptic mange in rabbits.
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27
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Hassani Z, Saleh A, Turpault S, Khiati S, Morelle W, Vignon J, Hugnot JP, Uro-Coste E, Legrand P, Delaforge M, Loiseau S, Clarion L, Lecouvey M, Volle JN, Virieux D, Pirat JL, Duffau H, Bakalara N. Phostine PST3.1a Targets MGAT5 and Inhibits Glioblastoma-Initiating Cell Invasiveness and Proliferation. Mol Cancer Res 2017. [DOI: 10.1158/1541-7786.mcr-17-0120] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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28
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Biochemistry and Physiology of Heavy Metal Resistance and Accumulation in Euglena. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 979:91-121. [PMID: 28429319 DOI: 10.1007/978-3-319-54910-1_6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Free-living microorganisms may become suitable models for removal of heavy metals from polluted water bodies, sediments, and soils by using and enhancing their metal accumulating abilities. The available research data indicate that protists of the genus Euglena are a highly promising group of microorganisms to be used in bio-remediation of heavy metal-polluted aerobic and anaerobic acidic aquatic environments. This chapter analyzes the variety of biochemical mechanisms evolved in E. gracilis to resist, accumulate and remove heavy metals from the environment, being the most relevant those involving (1) adsorption to the external cell pellicle; (2) intracellular binding by glutathione and glutathione polymers, and their further compartmentalization as heavy metal-complexes into chloroplasts and mitochondria; (3) polyphosphate biosynthesis; and (4) secretion of organic acids. The available data at the transcriptional, kinetic and metabolic levels on these metabolic/cellular processes are herein reviewed and analyzed to provide mechanistic basis for developing genetically engineered Euglena cells that may have a greater removal and accumulating capacity for bioremediation and recycling of heavy metals.
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29
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Abstract
Inorganic polyphosphate (polyP) accumulates in acidocalcisomes, acidic calcium stores that have been found from bacteria to human cells. Proton pumps, such as the vacuolar proton pyrophosphatase (V-H(+)-PPase or VP1), the vacuolar proton ATPase (V-H(+)-ATPase) or both, maintain their acidity. A vacuolar transporter chaperone (VTC) complex is involved in the synthesis and translocation of polyP to these organelles in several eukaryotes, such as yeast, trypanosomatids, Apicomplexan and algae. Studies in trypanosomatids have revealed the role of polyP and acidocalcisomes in osmoregulation and calcium signalling.
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30
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Yang Y, Ko TP, Chen CC, Huang G, Zheng Y, Liu W, Wang I, Ho MR, Hsu STD, O’Dowd B, Huff HC, Huang CH, Docampo R, Oldfield E, Guo RT. Structures of Trypanosome Vacuolar Soluble Pyrophosphatases: Antiparasitic Drug Targets. ACS Chem Biol 2016; 11:1362-71. [PMID: 26907161 DOI: 10.1021/acschembio.5b00724] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Trypanosomatid parasites are the causative agents of many neglected tropical diseases, including the leishmaniases, Chagas disease, and human African trypanosomiasis. They exploit unusual vacuolar soluble pyrophosphatases (VSPs), absent in humans, for cell growth and virulence and, as such, are drug targets. Here, we report the crystal structures of VSP1s from Trypanosoma cruzi and T. brucei, together with that of the T. cruzi protein bound to a bisphosphonate inhibitor. Both VSP1s form a hybrid structure containing an (N-terminal) EF-hand domain fused to a (C-terminal) pyrophosphatase domain. The two domains are connected via an extended loop of about 17 residues. Crystallographic analysis and size exclusion chromatography indicate that the VSP1s form tetramers containing head-to-tail dimers. Phosphate and diphosphate ligands bind in the PPase substrate-binding pocket and interact with several conserved residues, and a bisphosphonate inhibitor (BPH-1260) binds to the same site. On the basis of Cytoscape and other bioinformatics analyses, it is apparent that similar folds will be found in most if not all trypanosomatid VSP1s, including those found in insects (Angomonas deanei, Strigomonas culicis), plant pathogens (Phytomonas spp.), and Leishmania spp. Overall, the results are of general interest since they open the way to structure-based drug design for many of the neglected tropical diseases.
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Affiliation(s)
- Yunyun Yang
- College
of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
- Industrial
Enzymes National Engineering Laboratory, Tianjin Institute of Industrial
Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Tzu-Ping Ko
- Institute
of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan
| | - Chun-Chi Chen
- Industrial
Enzymes National Engineering Laboratory, Tianjin Institute of Industrial
Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Guozhong Huang
- Center
for Tropical and Emerging Global Diseases, and Department of Cellular Biology, University of Georgia, Athens, Georgia 30602, United States
| | - Yingying Zheng
- Industrial
Enzymes National Engineering Laboratory, Tianjin Institute of Industrial
Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Weidong Liu
- Industrial
Enzymes National Engineering Laboratory, Tianjin Institute of Industrial
Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Iren Wang
- Institute
of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan
| | - Meng-Ru Ho
- Institute
of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan
| | | | - Bing O’Dowd
- Department
of Chemistry, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Hannah C. Huff
- Department
of Chemistry, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Chun-Hsiang Huang
- Industrial
Enzymes National Engineering Laboratory, Tianjin Institute of Industrial
Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Roberto Docampo
- Center
for Tropical and Emerging Global Diseases, and Department of Cellular Biology, University of Georgia, Athens, Georgia 30602, United States
| | - Eric Oldfield
- Department
of Chemistry, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Rey-Ting Guo
- Industrial
Enzymes National Engineering Laboratory, Tianjin Institute of Industrial
Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
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31
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García-García JD, Sánchez-Thomas R, Moreno-Sánchez R. Bio-recovery of non-essential heavy metals by intra- and extracellular mechanisms in free-living microorganisms. Biotechnol Adv 2016; 34:859-873. [PMID: 27184302 DOI: 10.1016/j.biotechadv.2016.05.003] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 05/10/2016] [Accepted: 05/12/2016] [Indexed: 01/29/2023]
Abstract
Free-living microorganisms may become suitable models for recovery of non-essential and essential heavy metals from wastewater bodies and soils by using and enhancing their accumulating and/or leaching abilities. This review analyzes the variety of different mechanisms developed mainly in bacteria, protists and microalgae to accumulate heavy metals, being the most relevant those involving phytochelatin and metallothionein biosyntheses; phosphate/polyphosphate metabolism; compartmentalization of heavy metal-complexes into vacuoles, chloroplasts and mitochondria; and secretion of malate and other organic acids. Cyanide biosynthesis for extra-cellular heavy metal bioleaching is also examined. These metabolic/cellular processes are herein analyzed at the transcriptional, kinetic and metabolic levels to provide mechanistic basis for developing genetically engineered microorganisms with greater capacities and efficiencies for heavy metal recovery, recycling of heavy metals, biosensing of metal ions, and engineering of metalloenzymes.
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Affiliation(s)
- Jorge D García-García
- Departamento de Bioquímica, Instituto Nacional de Cardiología "Ignacio Chávez", México D.F. 14080, México.
| | - Rosina Sánchez-Thomas
- Departamento de Bioquímica, Instituto Nacional de Cardiología "Ignacio Chávez", México D.F. 14080, México
| | - Rafael Moreno-Sánchez
- Departamento de Bioquímica, Instituto Nacional de Cardiología "Ignacio Chávez", México D.F. 14080, México
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32
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Mallo N, Lamas J, DeFelipe AP, Sueiro RA, Fontenla F, Leiro JM. Enzymes Involved in Pyrophosphate and Calcium Metabolism as Targets for Anti-scuticociliate Chemotherapy. J Eukaryot Microbiol 2016; 63:505-15. [DOI: 10.1111/jeu.12294] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2015] [Revised: 12/18/2015] [Accepted: 01/05/2016] [Indexed: 12/20/2022]
Affiliation(s)
- Natalia Mallo
- Departamento de Microbiología y Parasitología; Instituto de Investigación y Análisis Alimentarios; Universidad de Santiago de Compostela; Santiago de Compostela Spain
| | - Jesús Lamas
- Departamento de Biología Celular y Ecología; Facultad de Biología; Instituto de Acuicultura; Universidad de Santiago de Compostela; Santiago de Compostela Spain
| | - Ana-Paula DeFelipe
- Departamento de Microbiología y Parasitología; Instituto de Investigación y Análisis Alimentarios; Universidad de Santiago de Compostela; Santiago de Compostela Spain
| | - Rosa-Ana Sueiro
- Departamento de Microbiología y Parasitología; Instituto de Investigación y Análisis Alimentarios; Universidad de Santiago de Compostela; Santiago de Compostela Spain
- Departamento de Biología Celular y Ecología; Facultad de Biología; Instituto de Acuicultura; Universidad de Santiago de Compostela; Santiago de Compostela Spain
| | - Francisco Fontenla
- Departamento de Biología Celular y Ecología; Facultad de Biología; Instituto de Acuicultura; Universidad de Santiago de Compostela; Santiago de Compostela Spain
| | - José-Manuel Leiro
- Departamento de Microbiología y Parasitología; Instituto de Investigación y Análisis Alimentarios; Universidad de Santiago de Compostela; Santiago de Compostela Spain
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33
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Jamwal A, Round AR, Bannwarth L, Venien-Bryan C, Belrhali H, Yogavel M, Sharma A. Structural and Functional Highlights of Vacuolar Soluble Protein 1 from Pathogen Trypanosoma brucei brucei. J Biol Chem 2015; 290:30498-513. [PMID: 26494625 DOI: 10.1074/jbc.m115.674176] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Indexed: 11/06/2022] Open
Abstract
Trypanosoma brucei (T. brucei) is responsible for the fatal human disease called African trypanosomiasis, or sleeping sickness. The causative parasite, Trypanosoma, encodes soluble versions of inorganic pyrophosphatases (PPase), also called vacuolar soluble proteins (VSPs), which are localized to its acidocalcisomes. The latter are acidic membrane-enclosed organelles rich in polyphosphate chains and divalent cations whose significance in these parasites remains unclear. We here report the crystal structure of T. brucei brucei acidocalcisomal PPases in a ternary complex with Mg(2+) and imidodiphosphate. The crystal structure reveals a novel structural architecture distinct from known class I PPases in its tetrameric oligomeric state in which a fused EF hand domain arranges around the catalytic PPase domain. This unprecedented assembly evident from TbbVSP1 crystal structure is further confirmed by SAXS and TEM data. SAXS data suggest structural flexibility in EF hand domains indicative of conformational plasticity within TbbVSP1.
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Affiliation(s)
- Abhishek Jamwal
- From the Structural and Computational Biology Group, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India
| | - Adam R Round
- the European Molecular Biology Laboratory, Grenoble Outstation, 38042 Grenoble, France, the Unit for Virus Host-Cell Interactions, University Grenoble Alpes-EMBL-CNRS, 38042 Grenoble, France, and
| | | | | | - Hassan Belrhali
- the European Molecular Biology Laboratory, Grenoble Outstation, 38042 Grenoble, France, the Unit for Virus Host-Cell Interactions, University Grenoble Alpes-EMBL-CNRS, 38042 Grenoble, France, and
| | - Manickam Yogavel
- From the Structural and Computational Biology Group, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India
| | - Amit Sharma
- From the Structural and Computational Biology Group, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India,
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34
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Huang G, Docampo R. Proteomic analysis of acidocalcisomes of Trypanosoma brucei uncovers their role in phosphate metabolism, cation homeostasis, and calcium signaling. Commun Integr Biol 2015; 8:e1017174. [PMID: 26480268 PMCID: PMC4594416 DOI: 10.1080/19420889.2015.1017174] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 01/21/2015] [Accepted: 01/22/2015] [Indexed: 12/23/2022] Open
Abstract
Trypanosomabrucei, the causative agent of African trypanosomiasis, is a unicellular parasite that possesses lysosome-related organelles known as acidocalcisomes. These organelles have been found from bacteria to human cells, and are characterized by their acidic nature and high calcium and polyphosphate (polyP) content. Our proteomic analysis of acidocalcisomes of T. brucei procyclic stages, together with in situ epitope-tagging and immunofluorescence assays with specific antibodies against selected proteins, established the presence of 2 H+ pumps, a vacuolar H+-ATPase and a vacuolar H+-pyrophosphatase, that acidify the organelles as well as of a number of transporters and channels involved in phosphate metabolism, cation uptake and calcium signaling. Together with recent work in other organisms, these results provide direct evidence that acidocalcisomes are especially adapted to accumulate polyP bound to cations and for calcium signaling.
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Affiliation(s)
- Guozhong Huang
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology; University of Georgia ; Athens, Georgia
| | - Roberto Docampo
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology; University of Georgia ; Athens, Georgia
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35
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A soluble pyrophosphatase is essential to oogenesis and is required for polyphosphate metabolism in the red flour beetle (Tribolium castaneum). Int J Mol Sci 2015; 16:6631-44. [PMID: 25811926 PMCID: PMC4424980 DOI: 10.3390/ijms16046631] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 02/13/2015] [Accepted: 03/09/2015] [Indexed: 11/26/2022] Open
Abstract
Polyphosphates have been found in all cell types examined to date and play diverse roles depending on the cell type. In eukaryotic organisms, polyphosphates have been mainly investigated in mammalian cells with few studies on insects. Some studies have demonstrated that a pyrophosphatase regulates polyphosphate metabolism, and most of them were performed on trypanosomatids. Here, we investigated the effects of sPPase gene knocked down in oogenesis and polyphosphate metabolism in the red flour beetle (Tribolium castaneum) A single sPPase gene was identified in insect genome and is maternally provided at the mRNA level and not restricted to any embryonic or extraembryonic region during embryogenesis. After injection of Tc-sPPase dsRNA, female survival was reduced to 15% of the control (dsNeo RNA), and egg laying was completely impaired. The morphological analysis by nuclear DAPI staining of the ovarioles in Tc-sPPase dsRNA-injected females showed that the ovariole number is diminished, degenerated oocytes can be observed, and germarium is reduced. The polyphosphate level was increased in cytoplasmic and nuclear fractions in Tc-sPPase RNAi; Concomitantly, the exopolyphosphatase activity decreased in both fractions. Altogether, these data suggest a role for sPPase in the regulation on polyphosphate metabolism in insects and provide evidence that Tc-sPPase is essential to oogenesis.
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36
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Dhanasekaran AR, Pearson JL, Ganesan B, Weimer BC. Metabolome searcher: a high throughput tool for metabolite identification and metabolic pathway mapping directly from mass spectrometry and using genome restriction. BMC Bioinformatics 2015; 16:62. [PMID: 25887958 PMCID: PMC4347650 DOI: 10.1186/s12859-015-0462-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 01/13/2015] [Indexed: 01/19/2023] Open
Abstract
Background Mass spectrometric analysis of microbial metabolism provides a long list of possible compounds. Restricting the identification of the possible compounds to those produced by the specific organism would benefit the identification process. Currently, identification of mass spectrometry (MS) data is commonly done using empirically derived compound databases. Unfortunately, most databases contain relatively few compounds, leaving long lists of unidentified molecules. Incorporating genome-encoded metabolism enables MS output identification that may not be included in databases. Using an organism’s genome as a database restricts metabolite identification to only those compounds that the organism can produce. Results To address the challenge of metabolomic analysis from MS data, a web-based application to directly search genome-constructed metabolic databases was developed. The user query returns a genome-restricted list of possible compound identifications along with the putative metabolic pathways based on the name, formula, SMILES structure, and the compound mass as defined by the user. Multiple queries can be done simultaneously by submitting a text file created by the user or obtained from the MS analysis software. The user can also provide parameters specific to the experiment’s MS analysis conditions, such as mass deviation, adducts, and detection mode during the query so as to provide additional levels of evidence to produce the tentative identification. The query results are provided as an HTML page and downloadable text file of possible compounds that are restricted to a specific genome. Hyperlinks provided in the HTML file connect the user to the curated metabolic databases housed in ProCyc, a Pathway Tools platform, as well as the KEGG Pathway database for visualization and metabolic pathway analysis. Conclusions Metabolome Searcher, a web-based tool, facilitates putative compound identification of MS output based on genome-restricted metabolic capability. This enables researchers to rapidly extend the possible identifications of large data sets for metabolites that are not in compound databases. Putative compound names with their associated metabolic pathways from metabolomics data sets are returned to the user for additional biological interpretation and visualization. This novel approach enables compound identification by restricting the possible masses to those encoded in the genome.
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Affiliation(s)
- A Ranjitha Dhanasekaran
- Center for Integrated BioSystems, Computer Science Department, Utah State University, Logan, 84322-8700, USA. .,Linda Crnic Institute for Down Syndrome, Department of Pediatrics, School of Medicine, University of Colorado Denver, 12700 E 19th Avenue, Aurora, CO, 80045, USA.
| | - Jon L Pearson
- Center for Integrated BioSystems, Computer Science Department, Utah State University, Logan, 84322-8700, USA. .,Spillman Technologies, 4625 West Lake Park Blvd, Salt Lake City, UT, 84120, USA.
| | - Balasubramanian Ganesan
- Center for Integrated BioSystems, Computer Science Department, Utah State University, Logan, 84322-8700, USA. .,Western Dairy Center, Department of Nutrition, Dietetics, and Food Sciences, Utah State University, Logan, 84322-8700, USA.
| | - Bart C Weimer
- University of California, Davis, School of Veterinary Medicine, 1089 Veterinary Medicine Dr., VM3B, Room 4023, Davis, CA, 95616, USA.
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Huang G, Ulrich PN, Storey M, Johnson D, Tischer J, Tovar JA, Moreno SNJ, Orlando R, Docampo R. Proteomic analysis of the acidocalcisome, an organelle conserved from bacteria to human cells. PLoS Pathog 2014; 10:e1004555. [PMID: 25503798 PMCID: PMC4263762 DOI: 10.1371/journal.ppat.1004555] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 11/05/2014] [Indexed: 01/12/2023] Open
Abstract
Acidocalcisomes are acidic organelles present in a diverse range of organisms from bacteria to human cells. In this study acidocalcisomes were purified from the model organism Trypanosoma brucei, and their protein composition was determined by mass spectrometry. The results, along with those that we previously reported, show that acidocalcisomes are rich in pumps and transporters, involved in phosphate and cation homeostasis, and calcium signaling. We validated the acidocalcisome localization of seven new, putative, acidocalcisome proteins (phosphate transporter, vacuolar H+-ATPase subunits a and d, vacuolar iron transporter, zinc transporter, polyamine transporter, and acid phosphatase), confirmed the presence of six previously characterized acidocalcisome proteins, and validated the localization of five novel proteins to different subcellular compartments by expressing them fused to epitope tags in their endogenous loci or by immunofluorescence microscopy with specific antibodies. Knockdown of several newly identified acidocalcisome proteins by RNA interference (RNAi) revealed that they are essential for the survival of the parasites. These results provide a comprehensive insight into the unique composition of acidocalcisomes of T. brucei, an important eukaryotic pathogen, and direct evidence that acidocalcisomes are especially adapted for the accumulation of polyphosphate.
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Affiliation(s)
- Guozhong Huang
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia, United States of America
| | - Paul N Ulrich
- Department of Biology, Georgia State University, Atlanta, Georgia, United States of America
| | - Melissa Storey
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia, United States of America
| | - Darryl Johnson
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, United States of America
| | - Julie Tischer
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia, United States of America
| | - Javier A Tovar
- Department of Biology, Georgia State University, Atlanta, Georgia, United States of America
| | - Silvia N J Moreno
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia, United States of America
| | - Ron Orlando
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, United States of America
| | - Roberto Docampo
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia, United States of America
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Freitas-Mesquita AL, Fonseca-de-Souza AL, Meyer-Fernandes JR. Leishmania amazonensis: characterization of an ecto-pyrophosphatase activity. Exp Parasitol 2013; 137:8-13. [PMID: 24316462 DOI: 10.1016/j.exppara.2013.11.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Revised: 11/22/2013] [Accepted: 11/27/2013] [Indexed: 01/30/2023]
Abstract
Several ecto-enzymatic activities have been described in the plasma membrane of the protozoan Leishmania amazonensis, which is the major etiological agent of diffuse cutaneous leishmaniasis in South America. These enzymes, including ecto-phosphatases, contribute to the survival of the parasite by participating in phosphate metabolism. This work identifies and characterizes the extracellular hydrolysis of inorganic pyrophosphate related to an ecto-pyrophosphatase activity of the promastigote form of L. amazonensis. This ecto-pyrophosphatase activity is insensitive to MnCl2 but is strongly stimulated by MgCl2. This stimulation was not observed during the hydrolysis of p-nitrophenyl phosphate (p-NPP) or β-glycerophosphate, two substrates for different ecto-phosphatases present in the L. amazonensis plasma membrane. Furthermore, extracellular PPi hydrolysis is more efficient at alkaline pHs, while p-NPP hydrolysis occurs mainly at acidic pHs. These results led us to conclude that extracellular PPi is hydrolyzed not by non-specific ecto-phosphatases but rather by a genuine ecto-pyrophosphatase. In the presence of 5mM MgCl2, the ecto-pyrophosphatase activity from L. amazonensis is sensitive to micromolar concentrations of NaF and millimolar concentrations of CaCl2. Moreover, this activity is significantly higher during the first days of L. amazonensis culture, which suggests a possible role for this enzyme in parasite growth.
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Affiliation(s)
- Anita Leocadio Freitas-Mesquita
- Instituto de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, 21941-590 Rio de Janeiro, RJ, Brazil; Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, 21941-590 Rio de Janeiro, RJ, Brazil
| | - André Luiz Fonseca-de-Souza
- Laboratório de Terapia e Fisiologia Celular e Molecular, Centro Universitário Estadual da Zona Oeste, 23070-200 Rio de Janeiro, RJ, Brazil
| | - José Roberto Meyer-Fernandes
- Instituto de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, 21941-590 Rio de Janeiro, RJ, Brazil; Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, 21941-590 Rio de Janeiro, RJ, Brazil.
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Galizzi M, Bustamante JM, Fang J, Miranda K, Soares Medeiros LC, Tarleton RL, Docampo R. Evidence for the role of vacuolar soluble pyrophosphatase and inorganic polyphosphate in Trypanosoma cruzi persistence. Mol Microbiol 2013; 90:699-715. [PMID: 24033456 DOI: 10.1111/mmi.12392] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/02/2013] [Indexed: 11/30/2022]
Abstract
Trypanosoma cruzi infection leads to development of a chronic disease but the mechanisms that the parasite utilizes to establish a persistent infection despite activation of a potent immune response by the host are currently unknown. Unusual characteristics of T. cruzi are that it possesses cellular levels of pyrophosphate (PPi ) at least 10 times higher than those of ATP and molar levels of inorganic polyphosphate (polyP) within acidocalcisomes. We characterized an inorganic soluble EF-hand containing pyrophosphatase from T. cruzi (TcVSP) that, depending on the pH and cofactors, can hydrolyse either pyrophosphate (PPi ) or polyphosphate (polyP). The enzyme is localized to both acidocalcisomes and cytosol. Overexpression of TcVSP (TcVSP-OE) resulted in a significant decrease in cytosolic PPi , and short and long-chain polyP levels. Additionally, the TcVSP-OE parasites showed a significant growth defect in fibroblasts, less responsiveness to hyperosmotic stress, and reduced persistence in tissues of mice, suggesting that PPi and polyP are essential for the parasite to resist the stressful conditions in the host and to maintain a persistent infection.
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Affiliation(s)
- Melina Galizzi
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, GA, 30602, USA
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Acidocalcisomes of Trypanosoma brucei have an inositol 1,4,5-trisphosphate receptor that is required for growth and infectivity. Proc Natl Acad Sci U S A 2013; 110:1887-92. [PMID: 23319604 DOI: 10.1073/pnas.1216955110] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Acidocalcisomes are acidic calcium stores rich in polyphosphate and found in a diverse range of organisms. The mechanism of Ca(2+) release from these organelles was unknown. Here we present evidence that Trypanosoma brucei acidocalcisomes possess an inositol 1,4,5-trisphosphate receptor (TbIP(3)R) for Ca(2+) release. Localization studies in cell lines expressing TbIP(3)R in its endogenous locus fused to an epitope tag revealed its partial colocalization with the vacuolar proton pyrophosphatase, a marker of acidocalcisomes. IP(3) was able to stimulate Ca(2+) release from a chicken B-lymphocyte cell line in which the genes for all three vertebrate IP(3)Rs have been stably ablated (DT40-3KO) and that were stably expressing TbIP(3)R, providing evidence of its function. IP(3) was also able to release Ca(2+) from permeabilized trypanosomes or isolated acidocalcisomes and photolytic release of IP(3) in intact trypanosomes loaded with Fluo-4 elicited a transient Ca(2+) increase in their cytosol. Ablation of TbIP(3)R by RNA interference caused a significant reduction of IP(3)-mediated Ca(2+) release in trypanosomes and resulted in defects in growth in culture and infectivity in mice. Taken together, the data provide evidence of the presence of a functional IP(3)R as a Ca(2+) release channel in acidocalcisomes of trypanosomes and suggest that a Ca(2+) signaling pathway that involves acidocalcisomes is required for growth and establishment of infection.
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New insights into roles of acidocalcisomes and contractile vacuole complex in osmoregulation in protists. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2013; 305:69-113. [PMID: 23890380 DOI: 10.1016/b978-0-12-407695-2.00002-0] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
While free-living protists are usually subjected to hyposmotic environments, parasitic protists are also in contact with hyperosmotic habitats. Recent work in one of these parasites, Trypanosoma cruzi, has revealed that its contractile vacuole complex, which usually collects and expels excess water as a mechanism of regulatory volume decrease after hyposmotic stress, has also a role in cell shrinking when the cells are submitted to hyperosmotic stress. Trypanosomes also have an acidic calcium store rich in polyphosphate (polyP), named the acidocalcisome, which is involved in their response to osmotic stress. Here, we review newly emerging insights on the role of acidocalcisomes and the contractile vacuole complex in the cellular response to hyposmotic and hyperosmotic stresses. We also review the current state of knowledge on the composition of these organelles and their other roles in calcium homeostasis and protein trafficking.
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Urbaniak MD, Guther MLS, Ferguson MAJ. Comparative SILAC proteomic analysis of Trypanosoma brucei bloodstream and procyclic lifecycle stages. PLoS One 2012; 7:e36619. [PMID: 22574199 PMCID: PMC3344917 DOI: 10.1371/journal.pone.0036619] [Citation(s) in RCA: 136] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Accepted: 04/03/2012] [Indexed: 11/19/2022] Open
Abstract
The protozoan parasite Trypanosoma brucei has a complex digenetic lifecycle between a mammalian host and an insect vector, and adaption of its proteome between lifecycle stages is essential to its survival and virulence. We have optimized a procedure for growing Trypanosoma brucei procyclic form cells in conditions suitable for stable isotope labeling by amino acids in culture (SILAC) and report a comparative proteomic analysis of cultured procyclic form and bloodstream form T. brucei cells. In total we were able to identify 3959 proteins and quantify SILAC ratios for 3553 proteins with a false discovery rate of 0.01. A large number of proteins (10.6%) are differentially regulated by more the 5-fold between lifecycle stages, including those involved in the parasite surface coat, and in mitochondrial and glycosomal energy metabolism. Our proteomic data is broadly in agreement with transcriptomic studies, but with significantly larger fold changes observed at the protein level than at the mRNA level.
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Affiliation(s)
- Michael D. Urbaniak
- Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - M. Lucia S Guther
- Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Michael A. J. Ferguson
- Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee, United Kingdom
- * E-mail:
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Docampo R, Jimenez V, King-Keller S, Li ZH, Moreno SNJ. The role of acidocalcisomes in the stress response of Trypanosoma cruzi. ADVANCES IN PARASITOLOGY 2011; 75:307-24. [PMID: 21820562 DOI: 10.1016/b978-0-12-385863-4.00014-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Acidocalcisomes of Trypanosoma cruzi are acidic calcium-containing organelles rich in phosphorus in the form of pyrophosphate (PP(i)) and polyphosphate (poly P). Acidification of the organelles is driven by vacuolar proton pumps, one of which, the vacuolar-type proton pyrophosphatase, is absent in mammalian cells. A calcium ATPase is involved in calcium uptake, and an aquaporin is important for water transport. Enzymes involved in the synthesis and degradation of PPi and poly P are present within the organelle. Acidocalcisomes function as storage sites for cations and phosphorus, participate in PP(i) and poly P metabolism and volume regulation and are essential for virulence. A signalling pathway involving cyclic AMP generation is important for fusion of acidocalcisomes to the contractile vacuole complex, transference of aquaporin and volume regulation. This pathway is an excellent target for chemotherapy as shown by the effects of phosphodiesterase C inhibitors on parasite survival.
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Affiliation(s)
- Roberto Docampo
- Department of Cellular Biology and Center for Tropical and Global Emerging Diseases, University of Georgia, Athens, GA, USA
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Huang G, Fang J, Sant'Anna C, Li ZH, Wellems DL, Rohloff P, Docampo R. Adaptor protein-3 (AP-3) complex mediates the biogenesis of acidocalcisomes and is essential for growth and virulence of Trypanosoma brucei. J Biol Chem 2011; 286:36619-30. [PMID: 21880705 PMCID: PMC3196089 DOI: 10.1074/jbc.m111.284661] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Revised: 08/24/2011] [Indexed: 12/19/2022] Open
Abstract
Acidocalcisomes are acidic calcium and polyphosphate storage organelles found in a diverse range of organisms. Here we present evidence that the biogenesis of acidocalcisomes in Trypanosoma brucei is linked to the expression of adaptor protein-3 (AP-3) complex. Localization studies in cell lines expressing β3 and δ subunits of AP-3 fused to epitope tags revealed their partial co-localization with the vacuolar proton pyrophosphatase, a marker of acidocalcisomes, with the Golgi marker Golgi reassembly and stacking protein, and with antibodies against the small GTPase Rab11. Ablation of the β3 subunit by RNA interference (RNAi) resulted in disappearance of acidocalcisomes from both procyclic and bloodstream form trypanosomes, as revealed by immmunofluorescence and electron microscopy assays, with no alterations in trafficking of different markers to lysosomes. Knockdown of the β3 subunit resulted in lower acidic calcium, pyrophosphate, and polyphosphate content as well as defects in growth in culture, resistance to osmotic stress, and virulence in mice. Similar results were obtained by knocking down the expression of the δ subunit of AP-3. These results indicate that AP-3 is essential for the biogenesis of acidocalcisomes and for growth and virulence of T. brucei.
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Affiliation(s)
- Guozhong Huang
- From the Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia 30602
| | - Jianmin Fang
- From the Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia 30602
| | - Celso Sant'Anna
- From the Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia 30602
| | - Zhu-Hong Li
- From the Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia 30602
| | - Dianne L. Wellems
- From the Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia 30602
| | - Peter Rohloff
- From the Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia 30602
| | - Roberto Docampo
- From the Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia 30602
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Abstract
Acidocalcisomes are acidic organelles containing calcium and a high concentration of phosphorus in the form of pyrophosphate (PP(i)) and polyphosphate (poly P). Organelles with these characteristics have been found from bacteria to human cells implying an early appearance and persistence over evolutionary time or their appearance by convergent evolution. Acidification of the organelles is driven by the presence of vacuolar proton pumps, one of which, the vacuolar proton pyrophosphatase, is absent in animals, where it is substituted by a vacuolar proton ATPase. A number of other pumps, antiporters, and channels have been described in acidocalcisomes of different species and are responsible for their internal content. Enzymes involved in the synthesis and degradation of PP(i) and poly P are present within the organelle. Acidocalcisomes function as storage sites for cations and phosphorus, and participate in PP(i) and poly P metabolism, calcium homeostasis, maintenance of intracellular pH, and osmoregulation. Experiments in which the acidocalcisome Ca(2+)-ATPase of different parasites were downregulated or eliminated, or acidocalcisome Ca(2+) was depleted revealed the importance of this store in Ca(2+) signaling needed for host invasion and virulence. Acidocalcisomes interact with other organelles in a number of organisms suggesting their association with the endosomal/lysosomal pathway, and are considered part of the lysosome-related group of organelles.
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Parsons M, Myler PJ, Berriman M, Roos DS, Stuart KD. Identity crisis? The need for systematic gene IDs. Trends Parasitol 2011; 27:183-4. [PMID: 21474380 DOI: 10.1016/j.pt.2011.02.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2011] [Revised: 02/25/2011] [Accepted: 02/25/2011] [Indexed: 11/30/2022]
Abstract
Recent years have seen an explosion in the availability of protozoan pathogen genome sequences. Although data regarding the underlying genome sequence remain relatively stable after the initial draft, understanding of specific gene function is increasing rapidly. This dichotomy is reflected in the relative stability of systematic gene identifiers (SysIDs(*)) in genome sequence databases, as compared to evolving and/or conflicting gene and gene product names. GenBank/EMBL/DDBJ accession numbers are important, but most protozoan parasite researchers use organism-based databases such as EuPathDB or GeneDB as their immediate resource for gene-based information because they not only provide sequence information but also functional information and links to references. Reference to SysIDs therefore provides a valuable bridge to this repository of information.
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Luginbuehl E, Kunz S, Wentzinger L, Freimoser F, Seebeck T. The exopolyphosphatase TbrPPX1 of Trypanosoma brucei. BMC Microbiol 2011; 11:4. [PMID: 21208463 PMCID: PMC3022644 DOI: 10.1186/1471-2180-11-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Accepted: 01/06/2011] [Indexed: 01/14/2023] Open
Abstract
Background Exopolyphosphatases and pyrophosphatases play important but still incompletely understood roles in energy metabolism, and also in other aspects of cell biology such as osmoregulation or signal transduction. Earlier work has suggested that a human exopolyphosphatase, Prune, might exhibit cyclic nucleotide phosphodiesterase activity. Results The kinetoplastida, a large order of unicellular eukaryotes that contains many important pathogens such as Trypanosoma brucei (human sleeping sickness), Trypanosoma cruzi (Chagas disease) or Leishmania ssp (several clinically dinstinct leishmaniases) all contain several exo- and pyrophosphatases. The current study provides a systematic classification of these enzymes, which now allows to situate the information that is already available on some of these enzymes. It then analyses the exopolyphosphatase TbrPPX1 of T. brucei in detail, using RNA interference and genetic knockouts in an attempt to define its function, and immunofluorescence microscopy to study its subcellular localization. TbrPPX1 is an exopolyphosphatase that does hydrolyze pentasodium triphosphate, but not organic triphosphates such as ATP, pyrophosphate or long-chain polyphosphates. Finally, the study investigates the potential cyclic nucleotide phosphodiesterase activity of TbrPPX1. Conclusions All kinetoplastid genomes that are currently available contain genes for an exopolyphosphatase and two classes of pyrophosphatases, one associated with the acidocalcisomes and one cytoplasmic. TbrPPX1 represents the T. brucei exopolyphosphatase. It is located throughout the cytoplasm, and its genetic ablation does not produce a dramatic phenotype. Importantly, TbrPPX1 does not exhibit any cyclic nucleotide specific phosphodiesterase activity, which definitively eliminates it as an additional player in cAMP signalling of the kinetoplastida.
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Affiliation(s)
- Edith Luginbuehl
- Institute of Cell Biology, University of Bern, Baltzerstrasse 4, CH-3012 Bern, Switzerland
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Rooney PJ, Ayong L, Tobin CM, Moreno SNJ, Knoll LJ. TgVTC2 is involved in polyphosphate accumulation in Toxoplasma gondii. Mol Biochem Parasitol 2010; 176:121-6. [PMID: 21195114 DOI: 10.1016/j.molbiopara.2010.12.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Revised: 12/20/2010] [Accepted: 12/22/2010] [Indexed: 10/18/2022]
Abstract
Polyphosphate is found in every cell, having roles in diverse processes, including differentiation and response to stress. In this study, we characterize a Toxoplasma gondii mutant containing an insertion within the carboxy-terminal end of a homolog of Saccharomyces cerevisiae Vtc2p, a component of the polyphosphate synthetic machinery. Locus TgVTC2 encodes a 140kDa protein containing conserved SPX, VTC and transmembrane domains. TgVTC2 localizes in punctate spots within the cytoplasm that do not co-localize with known markers. The TgVTC2 mutant showed dramatically reduced polyphosphate accumulation, a defect restored by introduction of TgVTC2 to the mutant. Insertion within TgVTC2 resulted in increased transcript levels for two loci, including a putative FIKK kinase. These transcript levels were restored to wild-type levels upon complementation with the TgVTC2 locus. The TgVTC2 locus was refractory to knockout, and may be essential. Analysis of this TgVTC2 mutant will facilitate dissection of the T. gondii polyphosphate synthesis pathway.
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Affiliation(s)
- Peggy J Rooney
- Department of Medical Microbiology and Immunology, University of Wisconsin School of Medicine and Public Health, Microbial Sciences Building Room 3345, 1550 Linden Drive, Madison, WI 53706, USA
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Zhang Q, Li Y, Tang CM. The role of the exopolyphosphatase PPX in avoidance by Neisseria meningitidis of complement-mediated killing. J Biol Chem 2010; 285:34259-68. [PMID: 20736171 DOI: 10.1074/jbc.m110.154393] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The complement system is critical for immunity against the important human pathogen Neisseria meningitidis. We describe the isolation of a meningococcal mutant lacking PPX, an exopolyphosphatase responsible for cleaving cellular polyphosphate, a polymer of tens to hundreds of orthophosphate residues found in virtually all living cells. Bacteria lacking PPX exhibit increased resistance to complement-mediated killing. By site directed mutagenesis, we define amino acids necessary for the biochemical activity of meningococcal PPX, including a conserved glutamate (Glu(117)) and residues in the Walker B box predicted to be involved in binding to phosphate. We show that the biochemical activity of PPX is necessary for interactions with the complement. The relative resistance of the ppx mutant does not result from changes in structures (such as capsule, lipopolysaccharide, and factor H-binding protein), which are known to be required for evasion of this key aspect of host immunity. Instead, expression of PPX modifies the interaction of N. meningitidis with the alternative pathway of complement activation.
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Affiliation(s)
- Qian Zhang
- Department of Microbiology, Centre for Molecular Microbiology and Infection, Flowers Building, Imperial College London, London SW7 2AZ, United Kingdom
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50
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Calcium- and polyphosphate-containing acidic granules of sea urchin eggs are similar to acidocalcisomes, but are not the targets for NAADP. Biochem J 2010; 429:485-95. [PMID: 20497125 PMCID: PMC2907711 DOI: 10.1042/bj20091956] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Acidocalcisomes are acidic calcium-storage compartments described from bacteria to humans and characterized by their high content in poly P (polyphosphate), a linear polymer of many tens to hundreds of Pi residues linked by high-energy phosphoanhydride bonds. In the present paper we report that millimolar levels of short-chain poly P (in terms of Pi residues) and inorganic PPi are present in sea urchin extracts as detected using 31P-NMR, enzymatic determinations and agarose gel electrophoresis. Poly P was localized to granules randomly distributed in the sea urchin eggs, as shown by labelling with the poly-P-binding domain of Escherichia coli exopolyphosphatase. These granules were enriched using iodixanol centrifugation and shown to be acidic and to contain poly P, as determined by Acridine Orange and DAPI (4',6'-diamidino-2-phenylindole) staining respectively. These granules also contained large amounts of calcium, sodium, magnesium, potassium and zinc, as detected by X-ray microanalysis, and bafilomycin A1-sensitive ATPase, pyrophosphatase and exopolyphosphatase activities, as well as Ca2+/H+ and Na+/H+ exchange activities, being therefore similar to acidocalcisomes described in other organisms. Calcium release from these granules induced by nigericin was associated with poly P hydrolysis. Although NAADP (nicotinic acid-adenine dinucleotide phosphate) released calcium from the granule fraction, this activity was not significantly enriched as compared with the NAADP-stimulated calcium release from homogenates and was not accompanied by poly P hydrolysis. GPN (glycyl-L-phenylalanine-naphthylamide) released calcium when added to sea urchin homogenates, but was unable to release calcium from acidocalcisome-enriched fractions, suggesting that these acidic stores are not the targets for NAADP.
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