1
|
Springer AL, Agrawal S, Chang EP. Malate dehydrogenase in parasitic protozoans: roles in metabolism and potential therapeutic applications. Essays Biochem 2024:EBC20230075. [PMID: 38938216 DOI: 10.1042/ebc20230075] [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: 03/06/2024] [Revised: 05/31/2024] [Accepted: 06/18/2024] [Indexed: 06/29/2024]
Abstract
The role of malate dehydrogenase (MDH) in the metabolism of various medically significant protozoan parasites is reviewed. MDH is an NADH-dependent oxidoreductase that catalyzes interconversion between oxaloacetate and malate, provides metabolic intermediates for both catabolic and anabolic pathways, and can contribute to NAD+/NADH balance in multiple cellular compartments. MDH is present in nearly all organisms; isoforms of MDH from apicomplexans (Plasmodium falciparum, Toxoplasma gondii, Cryptosporidium spp.), trypanosomatids (Trypanosoma brucei, T. cruzi) and anaerobic protozoans (Trichomonas vaginalis, Giardia duodenalis) are presented here. Many parasitic species have complex life cycles and depend on the environment of their hosts for carbon sources and other nutrients. Metabolic plasticity is crucial to parasite transition between host environments; thus, the regulation of metabolic processes is an important area to explore for therapeutic intervention. Common themes in protozoan parasite metabolism include emphasis on glycolytic catabolism, substrate-level phosphorylation, non-traditional uses of common pathways like tricarboxylic acid cycle and adapted or reduced mitochondria-like organelles. We describe the roles of MDH isoforms in these pathways, discuss unusual structural or functional features of these isoforms relevant to activity or drug targeting, and review current studies exploring the therapeutic potential of MDH and related genes. These studies show that MDH activity has important roles in many metabolic pathways, and thus in the metabolic transitions of protozoan parasites needed for success as pathogens.
Collapse
Affiliation(s)
- Amy L Springer
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, MA, U.S.A
| | - Swati Agrawal
- Department of Biological Sciences, University of Mary Washington, Fredericksburg, VA, U.S.A
| | - Eric P Chang
- Department of Chemistry and Physical Sciences, Pace University, New York, NY, U.S.A
| |
Collapse
|
2
|
Sasidharan S, Saudagar P. An anti-leishmanial compound 4',7-dihydroxyflavone elicits ROS-mediated apoptosis-like death in Leishmania parasite. FEBS J 2023. [PMID: 36871140 DOI: 10.1111/febs.16770] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 01/12/2023] [Accepted: 03/02/2023] [Indexed: 03/06/2023]
Abstract
The treatment for leishmaniasis is currently plagued by side effects such as toxicity and the emergence of drug resistance to the available repertoire of drugs, as well as the expense of these drugs. Considering such rising concerns, we report the anti-leishmanial activity and mechanism of a flavone compound 4',7-dihydroxyflavone (TI 4). Four flavanoids were initially screened for anti-leishmanial activity and cytotoxicity. The results showed that the compound TI 4 exhibited higher activity and selectivity index at the same time as maintaining low cytotoxicity. Preliminary microscopic studies and fluorescence-activated cell sorting analysis reported that the parasite underwent apoptosis on TI 4 treatment. Further in-depth studies revealed high reactive oxygen species (ROS) production and thiol levels in the parasites, suggesting ROS-mediated apoptosis in the parasites upon TI 4 treatment. Other apoptotic indicators such as intracellular Ca2+ and mitochondrial membrane potential also indicated the onset of apoptosis in the treated parasites. The mRNA expression levels signified that the redox metabolism genes were upregulated by two-fold along with the apoptotic genes. In summary, the use of TI 4 on Leishmania parasites induces ROS-mediated apoptosis; therefore, the compound has immense potential to be an anti-leishmanial drug. However, in vivo studies would be required to ascertain its safety and efficacy before we can exploit the compound against the growing leishmaniasis crisis.
Collapse
Affiliation(s)
- Santanu Sasidharan
- Department of Biotechnology, National Institute of Technology, Warangal, India
| | - Prakash Saudagar
- Department of Biotechnology, National Institute of Technology, Warangal, India
| |
Collapse
|
3
|
Sasidharan S, Saudagar P. Knockout of Tyrosine Aminotransferase Gene by Homologous Recombination Arrests Growth and Disrupts Redox Homeostasis in Leishmania Parasite. Parasitol Res 2022; 121:3229-3241. [PMID: 36056961 DOI: 10.1007/s00436-022-07642-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 08/24/2022] [Indexed: 11/26/2022]
Abstract
Tyrosine aminotransferase is a well-characterized enzyme in the Leishmania parasite, but the role of TAT in the parasite functioning remains largely unknown. In this study, we attempt to gain a better understanding of the enzyme's role in the parasite by gene knockout and overexpression of the TAT gene. The overexpression of TAT protein was well tolerated by the parasites in two independent repeats. Single knockout of TAT gene by homologous recombination, LdTAT+/- displayed distinct retardation in the proliferation rates and entered the death phase immediately. Morphology of LdTAT+/- parasites had important structural defects as they rounded up with elongated flagella. Gene regulation studies suggested the upregulation of key apoptotic and redox metabolism genes in LdTAT+/-. Moreover, LdTAT+/- cells accumulated higher ROS, thiols, intracellular Ca2+ concentrations, and mitochondrial membrane depolarization signifying the onset of apoptosis. Tocopherol levels were reduced by 50% in LdTAT+/- suggesting the involvement of TAT in tocopherol biosynthesis in the parasite. Overall, our results provide the first evidence that gene knockout of TAT results in apoptosis and that TAT is required for the survival and viability of Leishmania donovani.
Collapse
Affiliation(s)
- Santanu Sasidharan
- Department of Biotechnology, National Institute of Technology, Warangal, Telangana, 506004, India
| | - Prakash Saudagar
- Department of Biotechnology, National Institute of Technology, Warangal, Telangana, 506004, India.
| |
Collapse
|
4
|
Klöppel S, Richarz R, Wirtz DA, Vasenda N, König GM, Crüsemann M. A Specialized Dehydrogenase Provides l-Phenyllactate for FR900359 Biosynthesis. Chembiochem 2021; 23:e202100569. [PMID: 34846772 PMCID: PMC9299796 DOI: 10.1002/cbic.202100569] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/29/2021] [Indexed: 11/30/2022]
Abstract
d‐Phenyllactate (PLA) is a component of the selective Gq protein inhibitor and nonribosomal cyclic depsipeptide FR900359 (FR). Here we report a detailed biochemical investigation of pla biosynthesis and its incorporation into the natural product FR. The enzyme FrsC, member of the lactate/malate dehydrogenase superfamily, was shown to catalyze the formation of l‐PLA from phenylpyruvate. FrsC was kinetically characterized and its substrate specificity determined. Incorporation of l‐PLA was probed by assaying the adenylation domain FrsE‐A3 and feeding studies with a Chromobacterium vaccinii ΔfrsC mutant, confirming preferred activation of l‐PLA followed by on‐line epimerization to d‐pla. Finally, detailed bioinformatic analyses of FrsC revealed its close relation to malate dehydrogenases from primary metabolism and suggest extensions in the substrate binding loop to be responsible for its adaptation to accepting larger aromatic substrates with high specificity.
Collapse
Affiliation(s)
- Sophie Klöppel
- Institute of Pharmaceutical Biology, University of Bonn, Nussallee 6, 53115, Bonn, Germany
| | - René Richarz
- Institute of Pharmaceutical Biology, University of Bonn, Nussallee 6, 53115, Bonn, Germany
| | - Daniel A Wirtz
- Institute of Pharmaceutical Biology, University of Bonn, Nussallee 6, 53115, Bonn, Germany
| | - Natalia Vasenda
- Institute of Pharmaceutical Biology, University of Bonn, Nussallee 6, 53115, Bonn, Germany
| | - Gabriele M König
- Institute of Pharmaceutical Biology, University of Bonn, Nussallee 6, 53115, Bonn, Germany
| | - Max Crüsemann
- Institute of Pharmaceutical Biology, University of Bonn, Nussallee 6, 53115, Bonn, Germany
| |
Collapse
|
5
|
Trypanosoma cruzi synthesizes proline via a Δ1-pyrroline-5-carboxylate reductase whose activity is fine-tuned by NADPH cytosolic pools. Biochem J 2020; 477:1827-1845. [PMID: 32315030 DOI: 10.1042/bcj20200232] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 04/19/2020] [Accepted: 04/20/2020] [Indexed: 12/27/2022]
Abstract
In Trypanosoma cruzi, the etiological agent of Chagas disease, the amino acid proline participates in processes related to T. cruzi survival and infection, such as ATP production, cell differentiation, host-cell invasion, and in protection against osmotic, nutritional, and thermal stresses and oxidative imbalance. However, little is known about proline biosynthesis in this parasite. Δ1-Pyrroline-5-carboxylate reductase (P5CR, EC 1.5.1.2) catalyzes the biosynthesis of proline from Δ1-pyrroline-5-carboxylate (P5C) with concomitant NADPH oxidation. Herein, we show that unlike other eukaryotes, T. cruzi biosynthesizes proline from P5C, which is produced exclusively from glutamate. We found that TcP5CR is an NADPH-dependent cytosolic enzyme with a Kmapp for P5C of 27.7 μM and with a higher expression in the insect-resident form of the parasite. High concentrations of the co-substrate NADPH partially inhibited TcP5CR activity, prompting us to analyze multiple kinetic inhibition models. The model that best explained the obtained data included a non-competitive substrate inhibition mechanism (Kiapp=45±0.7μM). Therefore, TcP5CR is a candidate as a regulatory factor of this pathway. Finally, we show that P5C can exit trypanosomatid mitochondria in conditions that do not compromise organelle integrity. These observations, together with previously reported results, lead us to propose that in T. cruzi TcP5CR participates in a redox shuttle between the mitochondria and the cytoplasm. In this model, cytoplasmic redox equivalents from NADPH pools are transferred to the mitochondria using proline as a reduced metabolite, and shuttling to fuel electrons to the respiratory chain through proline oxidation by its cognate dehydrogenase.
Collapse
|
6
|
Campbell NK, Williams DG, Fitzgerald HK, Barry PJ, Cunningham CC, Nolan DP, Dunne A. Trypanosoma brucei Secreted Aromatic Ketoacids Activate the Nrf2/HO-1 Pathway and Suppress Pro-inflammatory Responses in Primary Murine Glia and Macrophages. Front Immunol 2019; 10:2137. [PMID: 31572363 PMCID: PMC6749089 DOI: 10.3389/fimmu.2019.02137] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 08/27/2019] [Indexed: 11/23/2022] Open
Abstract
African trypanosomes, such as Trypanosoma brucei (T. brucei), are protozoan parasites of the mammalian vasculature and central nervous system that are best known for causing fatal human sleeping sickness. As exclusively extracellular parasites, trypanosomes are subject to constant challenge from host immune defenses but they have developed very effective strategies to evade and modulate these responses to maintain an infection while simultaneously prolonging host survival. Here we investigate host parasite interactions, especially within the CNS context, which are not well-understood. We demonstrate that T. brucei strongly upregulates the stress response protein, Heme Oxygenase 1 (HO-1), in primary murine glia and macrophages in vitro. Furthermore, using a novel AHADHinT. brucei cell line, we demonstrate that specific aromatic ketoacids secreted by bloodstream forms of T. brucei are potent drivers of HO-1 expression and are capable of inhibiting pro-IL1β induction in both glia and macrophages. Additionally, we found that these ketoacids significantly reduced IL-6 and TNFα production by glia, but not macrophages. Finally, we present data to support Nrf2 activation as the mechanism of action by which these ketoacids upregulate HO-1 expression and mediate their anti-inflammatory activity. This study therefore reports a novel immune evasion mechanism, whereby T. brucei secretes amino-acid derived metabolites for the purpose of suppressing both the host CNS and peripheral immune response, potentially via induction of the Nrf2/HO-1 pathway.
Collapse
Affiliation(s)
- Nicole K Campbell
- School of Biochemistry and Immunology, Trinity College Dublin, University of Dublin, Dublin, Ireland
| | - David G Williams
- School of Biochemistry and Immunology, Trinity College Dublin, University of Dublin, Dublin, Ireland
| | - Hannah K Fitzgerald
- School of Biochemistry and Immunology, Trinity College Dublin, University of Dublin, Dublin, Ireland
| | - Paul J Barry
- School of Biochemistry and Immunology, Trinity College Dublin, University of Dublin, Dublin, Ireland
| | - Clare C Cunningham
- School of Biochemistry and Immunology, Trinity College Dublin, University of Dublin, Dublin, Ireland
| | - Derek P Nolan
- School of Biochemistry and Immunology, Trinity College Dublin, University of Dublin, Dublin, Ireland
| | - Aisling Dunne
- School of Biochemistry and Immunology, Trinity College Dublin, University of Dublin, Dublin, Ireland.,School of Medicine, Trinity Biomedical Biosciences Institute, Trinity College Dublin, Dublin, Ireland
| |
Collapse
|
7
|
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.
Collapse
|
8
|
Trypanosoma brucei metabolite indolepyruvate decreases HIF-1α and glycolysis in macrophages as a mechanism of innate immune evasion. Proc Natl Acad Sci U S A 2016; 113:E7778-E7787. [PMID: 27856732 DOI: 10.1073/pnas.1608221113] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The parasite Trypanasoma brucei causes African trypanosomiasis, known as sleeping sickness in humans and nagana in domestic animals. These diseases are a major burden in the 36 sub-Saharan African countries where the tsetse fly vector is endemic. Untreated trypanosomiasis is fatal and the current treatments are stage-dependent and can be problematic during the meningoencephalitic stage, where no new therapies have been developed in recent years and the current drugs have a low therapeutic index. There is a need for more effective treatments and a better understanding of how these parasites evade the host immune response will help in this regard. The bloodstream form of T. brucei excretes significant amounts of aromatic ketoacids, including indolepyruvate, a transamination product of tryptophan. This study demonstrates that this process is essential in bloodstream forms, is mediated by a specialized isoform of cytoplasmic aminotransferase and, importantly, reveals an immunomodulatory role for indolepyruvate. Indolepyruvate prevents the LPS-induced glycolytic shift in macrophages. This effect is the result of an increase in the hydroxylation and degradation of the transcription factor hypoxia-inducible factor-1α (HIF-1α). The reduction in HIF-1α levels by indolepyruvate, following LPS or trypanosome activation, results in a decrease in production of the proinflammatory cytokine IL-1β. These data demonstrate an important role for indolepyruvate in immune evasion by T. brucei.
Collapse
|
9
|
Abstract
The causative agent of Chagas disease, Trypanosoma cruzi, metabolizes glucose through two major pathways: glycolysis and the pentose phosphate pathway. Glucose is taken up via one facilitated transporter and its catabolism by the glycolytic pathway leads to the excretion of reduced products, succinate and l-alanine, even in the presence of oxygen; the first six enzymes are located in a peroxisome-like organelle, the glycosome, and the lack of regulatory controls in hexokinase and phosphofructokinase results in the lack of the Pasteur effect. All of the enzymes of the pentose phosphate pathway are present in the four major stages of the parasite's life cycle, and some of them are possible targets for chemotherapy. The gluconeogenic enzymes phosphoenolpyruvate carboxykinase and fructose-1,6-bisphosphatase are present, but there is no reserve polysaccharide.
Collapse
|
10
|
Leroux AE, Maugeri DA, Opperdoes FR, Cazzulo JJ, Nowicki C. Comparative studies on the biochemical properties of the malic enzymes from Trypanosoma cruzi and Trypanosoma brucei. FEMS Microbiol Lett 2010; 314:25-33. [PMID: 21105905 DOI: 10.1111/j.1574-6968.2010.02142.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Comparative studies showed that, like Trypanosoma cruzi, Trypanosoma brucei exhibits functional cytosolic and mitochondrial malic enzymes (MEs), which are specifically linked to NADP. Kinetic studies provided evidence that T. cruzi and T. brucei MEs display similarly high affinities towards NADP(+) and are also almost equally efficient in catalyzing the production of NADPH. Nevertheless, in contrast to the cytosolic ME from T. cruzi, which is highly activated by l-aspartate (over 10-fold), the T. brucei homologue is slightly more active (50%) in the presence of this amino acid. In T. brucei, both isozymes appear to be clearly more abundant in the insect stage, although they can be immunodetected in the bloodstream forms. By contrast, in T. cruzi the expression of the mitochondrial ME seems to be clearly upregulated in amastigotes, whereas the cytosolic isoform appears to be more abundant in the insect stages of the parasite. It might be hypothesized that in those environments where glucose is very low or absent, these pathogens depend on NADP-linked dehydrogenases such as the MEs for NADPH production, as in those conditions the pentose phosphate pathway cannot serve as a source of essential reducing power.
Collapse
Affiliation(s)
- Alejandro E Leroux
- Instituto de Química y Fisicoquímica Biológica IQUIFIB-CONICET, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina
| | | | | | | | | |
Collapse
|
11
|
Initial characterization of a recombinant kynureninase from Trypanosoma cruzi identified from an EST database. Gene 2009; 448:1-6. [DOI: 10.1016/j.gene.2009.08.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2009] [Revised: 08/12/2009] [Accepted: 08/13/2009] [Indexed: 11/29/2022]
|
12
|
Alcolea PJ, Alonso A, Sánchez-Gorostiaga A, Moreno-Paz M, Gómez MJ, Ramos I, Parro V, Larraga V. Genome-wide analysis reveals increased levels of transcripts related with infectivity in peanut lectin non-agglutinated promastigotes of Leishmania infantum. Genomics 2009; 93:551-64. [DOI: 10.1016/j.ygeno.2009.01.007] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2008] [Revised: 01/26/2009] [Accepted: 01/27/2009] [Indexed: 10/21/2022]
|
13
|
Marciano D, Llorente C, Maugeri DA, de la Fuente C, Opperdoes F, Cazzulo JJ, Nowicki C. Biochemical characterization of stage-specific isoforms of aspartate aminotransferases from Trypanosoma cruzi and Trypanosoma brucei. Mol Biochem Parasitol 2008; 161:12-20. [DOI: 10.1016/j.molbiopara.2008.05.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2008] [Revised: 05/20/2008] [Accepted: 05/21/2008] [Indexed: 12/01/2022]
|
14
|
Nowicki C, Cazzulo JJ. Aromatic amino acid catabolism in trypanosomatids. Comp Biochem Physiol A Mol Integr Physiol 2007; 151:381-390. [PMID: 17433885 DOI: 10.1016/j.cbpa.2007.03.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2006] [Revised: 03/07/2007] [Accepted: 03/08/2007] [Indexed: 11/25/2022]
Abstract
Trypanosomatids cause important human diseases, like sleeping sickness, Chagas disease, and the leishmaniases. Unlike in the mammalian host, the metabolism of aromatic amino acids is a very simple pathway in these parasites. Trypanosoma brucei and Trypanosoma cruzi transaminate the three aromatic amino acids, the resulting 2-oxo acids being reduced to the corresponding lactate derivatives and excreted. In T. cruzi, two enzymes are involved in this process: a tyrosine aminotransferase (TAT), which despite a high sequence similarity with the mammalian enzyme, has a different substrate specificity; and an aromatic L-2-hydroxyacid dehydrogenase (AHADH), which belongs to the subfamily of the cytosolic malate dehydrogenases (MDHs), yet has no MDH activity. In T. cruzi AHADH the substitution of Ala102 for Arg enables AHADH to reduce oxaloacetate. In the members of the 2-hydroxyacid dehydrogenases family, the residue at this position is known to be responsible for substrate specificity. T. cruzi does not possess a cytosolic MDH but contains a mitochondrial and a glycosomal MDH; by contrast T. brucei and Leishmania spp. possess a cytosolic MDH in addition to glycosomal and mitochondrial isozymes. Although Leishmania mexicana also transaminates aromatic amino acids through a broad specificity aminotransferase, the latter presents low sequence similarity with TATs, and this parasite does not seem to have an enzyme equivalent to T. cruzi AHADH. Therefore, these closely related primitive eukaryotes have developed aromatic amino acid catabolism systems using different enzymes and probably for different metabolic purposes.
Collapse
Affiliation(s)
- Cristina Nowicki
- IQUIFIB/Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, CP1113, Argentina.
| | - Juan J Cazzulo
- IIB-INTECH, Instituto de Investigaciones Biotecnológicas, Universidad Nacional de General San Martín-CONICET, Av. Gral. Paz y Albarellos, INTI, edificio 24, 1650 San Martín, Buenos Aires, Argentina
| |
Collapse
|
15
|
Leroux A, Fleming-Canepa X, Aranda A, Maugeri D, Cazzulo JJ, Sánchez MA, Nowicki C. Functional characterization and subcellular localization of the three malate dehydrogenase isozymes in Leishmania spp. Mol Biochem Parasitol 2006; 149:74-85. [PMID: 16750864 DOI: 10.1016/j.molbiopara.2006.04.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2005] [Revised: 04/25/2006] [Accepted: 04/27/2006] [Indexed: 11/19/2022]
Abstract
As part of a study on the malate dehydrogenase isozymes (MDHs) from Trypanosomatids, three different fractions with MDH activity were obtained from crude extracts of Leishmania mexicana promastigotes combining two different chromatographic steps. Gel filtration chromatography in native conditions showed that most of the MDH activity present in the crude extracts eluted in a single peak, which corresponded to a lower apparent molecular mass ( congruent with 57kDa) than the value expected for typical MDHs. To further characterize the leishmanial isozymes, three putative MDH genes, presumably corresponding to the mitochondrial, glycosomal and cytosolic isoforms were amplified by PCR, cloned into bacterial expression vectors, and the recombinant enzymes purified. Digitonin extraction of intact L. mexicana promastigotes and immunofluorescence microscopy of L. major promastigotes confirmed the subcellular compartmentation of each of the three isozymes. Western blot analysis showed that the three MDHs are developmentally regulated. At the protein level, these isozymes are remarkably more abundant in amastigotes than in promastigotes of L. mexicana. Altogether our results demonstrate the presence of three MDH isoforms with slightly distinct biochemical properties and different subcellular localization in Leishmania spp. Presumably the functional and biochemical features of these isozymes reflect the metabolic adaptation to the different nutrient sources these parasites have to face along their life cycle. These results also emphasize the differences among Trypanosomatids in this area of metabolism, since in the case of Trypanosoma brucei the cMDH is the only isoform expressed in bloodstream trypomastigotes, whereas in Trypanosoma cruzi cMDH is absent.
Collapse
Affiliation(s)
- Alejandro Leroux
- Instituto de Química y Fisicoquímica Biológica IQUIFIB-CONICET, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, CP1113 Buenos Aires, Argentina
| | | | | | | | | | | | | |
Collapse
|
16
|
Aranda A, Maugeri D, Uttaro AD, Opperdoes F, Cazzulo JJ, Nowicki C. The malate dehydrogenase isoforms from Trypanosoma brucei: subcellular localization and differential expression in bloodstream and procyclic forms. Int J Parasitol 2005; 36:295-307. [PMID: 16321390 DOI: 10.1016/j.ijpara.2005.09.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2005] [Revised: 09/14/2005] [Accepted: 09/16/2005] [Indexed: 11/24/2022]
Abstract
Trypanosoma brucei procyclic forms possess three different malate dehydrogenase isozymes that could be separated by hydrophobic interaction chromatography and were recognized as the mitochondrial, glycosomal and cytosolic malate dehydrogenase isozymes. The latter is the only malate dehydrogenase expressed in the bloodstream forms, thus confirming that the expression of malate dehydrogenase isozymes is regulated during the T. brucei life cycle. To achieve further biochemical characterization, the genes encoding mitochondrial and glycosomal malate dehydrogenase were cloned on the basis of previously reported nucleotide sequences and the recombinant enzymes were functionally expressed in Escherichia coli cultures. Mitochondrial malate dehydrogenase showed to be more active than glycosomal malate dehydrogenase in the reduction of oxaloacetate; nearly 80% of the total activity in procyclic crude extracts corresponds to the former isozyme which also catalyzes, although less efficiently, the reduction of p-hydroxyphenyl-pyruvate. The rabbit antisera raised against each of the recombinant isozymes showed that the three malate dehydrogenases do not cross-react immunologically. Immunofluorescence experiments using these antisera confirmed the glycosomal and mitochondrial localization of glycosomal and mitochondrial malate dehydrogenase, as well as a cytosolic localization for the third malate dehydrogenase isozyme. These results clearly distinguish Trypanosoma brucei from Trypanosoma cruzi, since in the latter parasite a cytosolic malate dehydrogenase is not present and mitochondrial malate dehydrogenase specifically reduces oxaloacetate.
Collapse
Affiliation(s)
- Alejandro Aranda
- Instituto de Química y Fisicoquímica Biológica IQUIFIB-CONICET, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, CP1113, Argentina
| | | | | | | | | | | |
Collapse
|
17
|
Vernal J, José Cazzulo J, Nowicki C. Cloning and heterologous expression of a broad specificity aminotransferase ofLeishmania mexicanapromastigotes. FEMS Microbiol Lett 2003; 229:217-22. [PMID: 14680702 DOI: 10.1016/s0378-1097(03)00824-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
We have previously reported that Leishmania mexicana promastigotes possess a broad substrate specificity aminotransferase (BSAT), able to transaminate aspartate, aromatic amino acids, methionine and leucine. We have confirmed now this unusual substrate specificity by cloning its gene and expressing in Escherichia coli the recombinant active protein. The amino acid sequence of BSAT shares over 40% identity with other eukaryotic and prokaryotic aspartate aminotransferases, thus showing that the enzyme belongs to the subfamily Ialpha of aminotransferases, and has only 6% identity with the tyrosine aminotransferase from Trypanosoma cruzi, which has a similar substrate specificity. The production of recombinant active enzyme in good yields opens up the possibility of obtaining its 3D-structure, in order to investigate the structural basis of the broad substrate specificity.
Collapse
Affiliation(s)
- Javier Vernal
- Instituto de Química y Fisicoquímica Biológica IQUIFIB-CONICET, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, CP1113 Buenos Aires, Argentina
| | | | | |
Collapse
|
18
|
Hannaert V, Bringaud F, Opperdoes FR, Michels PAM. Evolution of energy metabolism and its compartmentation in Kinetoplastida. KINETOPLASTID BIOLOGY AND DISEASE 2003; 2:11. [PMID: 14613499 PMCID: PMC317351 DOI: 10.1186/1475-9292-2-11] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2003] [Accepted: 10/28/2003] [Indexed: 04/27/2023]
Abstract
Kinetoplastida are protozoan organisms that probably diverged early in evolution from other eukaryotes. They are characterized by a number of unique features with respect to their energy and carbohydrate metabolism. These organisms possess peculiar peroxisomes, called glycosomes, which play a central role in this metabolism; the organelles harbour enzymes of several catabolic and anabolic routes, including major parts of the glycolytic and pentosephosphate pathways. The kinetoplastid mitochondrion is also unusual with regard to both its structural and functional properties.In this review, we describe the unique compartmentation of metabolism in Kinetoplastida and the metabolic properties resulting from this compartmentation. We discuss the evidence for our recently proposed hypothesis that a common ancestor of Kinetoplastida and Euglenida acquired a photosynthetic alga as an endosymbiont, contrary to the earlier notion that this event occurred at a later stage of evolution, in the Euglenida lineage alone. The endosymbiont was subsequently lost from the kinetoplastid lineage but, during that process, some of its pathways of energy and carbohydrate metabolism were sequestered in the kinetoplastid peroxisomes, which consequently became glycosomes. The evolution of the kinetoplastid glycosomes and the possible selective advantages of these organelles for Kinetoplastida are discussed. We propose that the possession of glycosomes provided metabolic flexibility that has been important for the organisms to adapt easily to changing environmental conditions. It is likely that metabolic flexibility has been an important selective advantage for many kinetoplastid species during their evolution into the highly successful parasites today found in many divergent taxonomic groups.Also addressed is the evolution of the kinetoplastid mitochondrion, from a supposedly pluripotent organelle, attributed to a single endosymbiotic event that resulted in all mitochondria and hydrogenosomes of extant eukaryotes. Furthermore, indications are presented that Kinetoplastida may have acquired other enzymes of energy and carbohydrate metabolism by various lateral gene transfer events different from those that involved the algal- and alpha-proteobacterial-like endosymbionts responsible for the respective formation of the glycosomes and mitochondria.
Collapse
Affiliation(s)
- Véronique Hannaert
- Research Unit for Tropical Diseases, Christian de Duve Institute of Cellular Pathology and Laboratory of Biochemistry, Université Catholique de Louvain, Avenue Hippocrate 74, B-1200 Brussels, Belgium
| | - Frédéric Bringaud
- Laboratoire de Parasitologie Moléculaire, Université Victor Segalen, Bordeaux II, UMR-CNRS 5016, 146 Rue Léo Saignat, 33076 Bordeaux Cedex, France
| | - Fred R Opperdoes
- Research Unit for Tropical Diseases, Christian de Duve Institute of Cellular Pathology and Laboratory of Biochemistry, Université Catholique de Louvain, Avenue Hippocrate 74, B-1200 Brussels, Belgium
| | - Paul AM Michels
- Research Unit for Tropical Diseases, Christian de Duve Institute of Cellular Pathology and Laboratory of Biochemistry, Université Catholique de Louvain, Avenue Hippocrate 74, B-1200 Brussels, Belgium
| |
Collapse
|
19
|
Hannaert V, Saavedra E, Duffieux F, Szikora JP, Rigden DJ, Michels PAM, Opperdoes FR. Plant-like traits associated with metabolism of Trypanosoma parasites. Proc Natl Acad Sci U S A 2003; 100:1067-71. [PMID: 12552132 PMCID: PMC298727 DOI: 10.1073/pnas.0335769100] [Citation(s) in RCA: 157] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Trypanosomatid parasites cause serious diseases among humans, livestock, and plants. They belong to the order of the Kinetoplastida and form, together with the Euglenida, the phylum Euglenozoa. Euglenoid algae possess plastids capable of photosynthesis, but plastids are unknown in trypanosomatids. Here we present molecular evidence that trypanosomatids possessed a plastid at some point in their evolutionary history. Extant trypanosomatid parasites, such as Trypanosoma and Leishmania, contain several "plant-like" genes encoding homologs of proteins found in either chloroplasts or the cytosol of plants and algae. The data suggest that kinetoplastids and euglenoids acquired plastids by endosymbiosis before their divergence and that the former lineage subsequently lost the organelle but retained numerous genes. Several of the proteins encoded by these genes are now, in the parasites, found inside highly specialized peroxisomes, called glycosomes, absent from all other eukaryotes, including euglenoids.
Collapse
Affiliation(s)
- Veronique Hannaert
- Research Unit for Tropical Diseases and Laboratory of Biochemistry, Christian de Duve Institute of Cellular Pathology and Université Catholique de Louvain, B-1200 Brussels, Belgium
| | | | | | | | | | | | | |
Collapse
|
20
|
Vernal J, Fiser A, Sali A, Müller M, Cazzulo JJ, Nowicki C. Probing the specificity of a trypanosomal aromatic alpha-hydroxy acid dehydrogenase by site-directed mutagenesis. Biochem Biophys Res Commun 2002; 293:633-9. [PMID: 12054650 DOI: 10.1016/s0006-291x(02)00270-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The aromatic l-alpha-hydroxy acid dehydrogenase (AHDAH) from Trypanosoma cruzi has over 50% sequence identity with cytosolic malate dehydrogenases (cMDHs), yet it is unable to reduce oxaloacetate. Molecular modeling of the three-dimensional structure of AHADH using the pig cMDH as template directed the construction of several mutants. AHADH shares with MDHs the essential catalytic residues H195 and R171 (using Eventoff's numbering). The AHADH A102R mutant became able to reduce oxaloacetate, while remaining fully active towards aromatic alpha-oxoacids. The Y237G mutant diminished its affinity for all of the natural substrates, whereas the double mutant A102R/Y237G was more active than Y237G and had similar activity with oxaloacetate and with aromatic substrates. The present results reinforce our proposal that AHADH arose by a moderate number of point mutations from a cMDH no longer present in the parasite.
Collapse
Affiliation(s)
- Javier Vernal
- IQUIFIB, CONICET-Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, 1113 Buenos Aires, Argentina
| | | | | | | | | | | |
Collapse
|
21
|
Vernal J, Muñoz-Jordán J, Müller M, Cazzulo JJ, Nowicki C. Sequencing and heterologous expression of a cytosolic-type malate dehydrogenase of Trypanosoma brucei. Mol Biochem Parasitol 2001; 117:217-21. [PMID: 11606232 DOI: 10.1016/s0166-6851(01)00343-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- J Vernal
- Instituto de Química y Fisicoquímica Biológica IQUIFIB-CONICET, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, 1113 Buenos Aires, Argentina
| | | | | | | | | |
Collapse
|
22
|
Paris G, Cremona ML, Amaya MF, Buschiazzo A, Giambiagi S, Frasch AC, Alzari PM. Probing molecular function of trypanosomal sialidases: single point mutations can change substrate specificity and increase hydrolytic activity. Glycobiology 2001; 11:305-11. [PMID: 11358879 DOI: 10.1093/glycob/11.4.305] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Sialidases are present on the surface of several trypanosomatid protozoan parasites. They are highly specific for sialic acid linked in alpha-(2,3) to a terminal beta-galactose and include the strictly hydrolytic enzymes and trans-sialidases (sialyl-transferases). Based on the structural comparison of the sialidase from Trypanosoma rangeli and the trans-sialidase from T. cruzi (the agent of Chagas' disease in humans), we have explored the role of specific amino acid residues sought to be important for substrate specificity. The substitution of a conserved tryptophanyl residue in the two enzymes, Trp312/313-Ala, changed substrate specificity, rendering the point mutants capable to hydrolyze both alpha-(2,3)- and alpha-(2,6)-linked sialoconjugates. The same mutation abolished sialyl-transferase activity, indicating that transfer (but not hydrolysis) requires a precise orientation of the bound substrate. The exchange substitution of another residue that modulates oligosaccharide binding, Gln284-Pro, was found to significantly increase the hydrolytic activity of sialidase, and residue Tyr119 was confirmed to be part of a second binding site for the acceptor substrate in trans-sialidase. Together with the structural information, these results provide a consistent framework to account for the unique enzymatic properties of trypanosome trans-sialidases.
Collapse
Affiliation(s)
- G Paris
- Instituto de Investigaciones Biotecnológicas, Universidad Nacional de San Martín, CC30, 1650 San Martín, Argentina
| | | | | | | | | | | | | |
Collapse
|