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Opperdoes FR, Záhonová K, Škodová-Sveráková I, Bučková B, Chmelová Ľ, Lukeš J, Yurchenko V. In silico prediction of the metabolism of Blastocrithidia nonstop, a trypanosomatid with non-canonical genetic code. BMC Genomics 2024; 25:184. [PMID: 38365628 PMCID: PMC10874023 DOI: 10.1186/s12864-024-10094-8] [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] [Received: 09/03/2023] [Accepted: 02/06/2024] [Indexed: 02/18/2024] Open
Abstract
BACKGROUND Almost all extant organisms use the same, so-called canonical, genetic code with departures from it being very rare. Even more exceptional are the instances when a eukaryote with non-canonical code can be easily cultivated and has its whole genome and transcriptome sequenced. This is the case of Blastocrithidia nonstop, a trypanosomatid flagellate that reassigned all three stop codons to encode amino acids. RESULTS We in silico predicted the metabolism of B. nonstop and compared it with that of the well-studied human parasites Trypanosoma brucei and Leishmania major. The mapped mitochondrial, glycosomal and cytosolic metabolism contains all typical features of these diverse and important parasites. We also provided experimental validation for some of the predicted observations, concerning, specifically presence of glycosomes, cellular respiration, and assembly of the respiratory complexes. CONCLUSIONS In an unusual comparison of metabolism between a parasitic protist with a massively altered genetic code and its close relatives that rely on a canonical code we showed that the dramatic differences on the level of nucleic acids do not seem to be reflected in the metabolisms. Moreover, although the genome of B. nonstop is extremely AT-rich, we could not find any alterations of its pyrimidine synthesis pathway when compared to other trypanosomatids. Hence, we conclude that the dramatic alteration of the genetic code of B. nonstop has no significant repercussions on the metabolism of this flagellate.
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Affiliation(s)
- Fred R Opperdoes
- de Duve Institute, Université catholique de Louvain, Brussels, Belgium
| | - Kristína Záhonová
- Life Science Research Centre, Faculty of Science, University of Ostrava, Ostrava, Czechia
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czechia
- Department of Parasitology, Faculty of Science, Charles University, BIOCEV, Vestec, Czechia
- Division of Infectious Diseases, Department of Medicine, University of Alberta, Edmonton, Canada
| | - Ingrid Škodová-Sveráková
- Life Science Research Centre, Faculty of Science, University of Ostrava, Ostrava, Czechia
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czechia
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia
| | - Barbora Bučková
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia
| | - Ľubomíra Chmelová
- Life Science Research Centre, Faculty of Science, University of Ostrava, Ostrava, Czechia
| | - Julius Lukeš
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czechia
- Faculty of Science, University of South Bohemia, České Budějovice, Czechia
| | - Vyacheslav Yurchenko
- Life Science Research Centre, Faculty of Science, University of Ostrava, Ostrava, Czechia.
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Berneburg I, Stumpf M, Velten AS, Rahlfs S, Przyborski J, Becker K, Fritz-Wolf K. Structure of Leishmania donovani 6-Phosphogluconate Dehydrogenase and Inhibition by Phosphine Gold(I) Complexes: A Potential Approach to Leishmaniasis Treatment. Int J Mol Sci 2023; 24:ijms24108615. [PMID: 37239962 DOI: 10.3390/ijms24108615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 05/08/2023] [Accepted: 05/09/2023] [Indexed: 05/28/2023] Open
Abstract
As unicellular parasites are highly dependent on NADPH as a source for reducing equivalents, the main NADPH-producing enzymes glucose 6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6PGD) of the pentose phosphate pathway are considered promising antitrypanosomatid drug targets. Here we present the biochemical characterization and crystal structure of Leishmania donovani 6PGD (Ld6PGD) in complex with NADP(H). Most interestingly, a previously unknown conformation of NADPH is visible in this structure. In addition, we identified auranofin and other gold(I)-containing compounds as efficient Ld6PGD inhibitors, although it has so far been assumed that trypanothione reductase is the sole target of auranofin in Kinetoplastida. Interestingly, 6PGD from Plasmodium falciparum is also inhibited at lower micromolar concentrations, whereas human 6PGD is not. Mode-of-inhibition studies indicate that auranofin competes with 6PG for its binding site followed by a rapid irreversible inhibition. By analogy with other enzymes, this suggests that the gold moiety is responsible for the observed inhibition. Taken together, we identified gold(I)-containing compounds as an interesting class of inhibitors against 6PGDs from Leishmania and possibly from other protozoan parasites. Together with the three-dimensional crystal structure, this provides a valid basis for further drug discovery approaches.
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Affiliation(s)
- Isabell Berneburg
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, 35392 Giessen, Germany
| | - Michaela Stumpf
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, 35392 Giessen, Germany
| | - Ann-Sophie Velten
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, 35392 Giessen, Germany
| | - Stefan Rahlfs
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, 35392 Giessen, Germany
| | - Jude Przyborski
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, 35392 Giessen, Germany
| | - Katja Becker
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, 35392 Giessen, Germany
| | - Karin Fritz-Wolf
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, 35392 Giessen, Germany
- Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
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3
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Hanau S, Helliwell JR. 6-Phosphogluconate dehydrogenase and its crystal structures. Acta Crystallogr F Struct Biol Commun 2022; 78:96-112. [PMID: 35234135 PMCID: PMC8900737 DOI: 10.1107/s2053230x22001091] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 01/31/2022] [Indexed: 11/10/2022] Open
Abstract
6-Phosphogluconate dehydrogenase (6PGDH; EC 1.1.1.44) catalyses the oxidative decarboxylation of 6-phosphogluconate to ribulose 5-phosphate in the context of the oxidative part of the pentose phosphate pathway. Depending on the species, it can be a homodimer or a homotetramer. Oligomerization plays a functional role not only because the active site is at the interface between subunits but also due to the interlocking tail-modulating activity, similar to that of isocitrate dehydrogenase and malic enzyme, which catalyse a similar type of reaction. Since the pioneering crystal structure of sheep liver 6PGDH, which allowed motifs common to the β-hydroxyacid dehydrogenase superfamily to be recognized, several other 6PGDH crystal structures have been solved, including those of ternary complexes. These showed that more than one conformation exists, as had been suggested for many years from enzyme studies in solution. It is inferred that an asymmetrical conformation with a rearrangement of one of the two subunits underlies the homotropic cooperativity. There has been particular interest in the presence or absence of sulfate during crystallization. This might be related to the fact that this ion, which is a competitive inhibitor that binds in the active site, can induce the same 6PGDH configuration as in the complexes with physiological ligands. Mutagenesis, inhibitors, kinetic and binding studies, post-translational modifications and research on the enzyme in cancer cells have been complementary to the crystallographic studies. Computational modelling and new structural studies will probably help to refine the understanding of the functioning of this enzyme, which represents a promising therapeutic target in immunity, cancer and infective diseases. 6PGDH also has applied-science potential as a biosensor or a biobattery. To this end, the enzyme has been efficiently immobilized on specific polymers and nanoparticles. This review spans the 6PGDH literature and all of the 6PGDH crystal structure data files held by the Protein Data Bank.
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Jakkula P, Narsimulu B, Qureshi IA. Biochemical and structural insights into 6-phosphogluconate dehydrogenase from Leishmania donovani. Appl Microbiol Biotechnol 2021; 105:5471-5489. [PMID: 34250571 DOI: 10.1007/s00253-021-11434-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 05/19/2021] [Accepted: 06/13/2021] [Indexed: 11/29/2022]
Abstract
6-phosphogluconate dehydrogenase (6PGDH) participates in pentose phosphate pathway of glucose metabolism by catalyzing oxidative decarboxylation of 6-phsophogluconate (6PG) and its absence has been lethal for several eukaryotes. Despite being a validated drug target in many organisms like Plasmodium, the enzyme has not been explored in leishmanial parasites. In the present study, 6PGDH of Leishmania donovani (Ld6PGDH) is cloned and purified followed by its characterization using biochemical and structural approaches. Ld6PGDH lacks the glycine-serine-rich sequence at its C-terminal that is present in other eukaryotes including humans. Leishmanial 6PGDH possesses more affinity for substrate (6PG) and cofactor (NADP) in comparison to that of human. The enzymatic activity is inhibited by gentamicin and cefuroxime through competitive mode with functioning more potently towards leishmanial 6PGDH than its human counterpart. CD analysis has shown higher α-helical content in the secondary structure of Ld6PGDH, while fluorescence studies revealed that tryptophan residues are not completely accessible to solvent environment. The three-dimensional structure was generated through homology modelling and docked with substrate and cofactor. The docking studies demonstrated two separate binding pockets for 6PG and NADP with higher affinity for the cofactor binding, and Asn105 is interacting with substrate as well as the cofactor. Additionally, MD simulation has shown complexes of Ld6PGDH with 6PG and NADP to be more stable than its apo form. Altogether, the present study might provide the foundation to investigate this enzyme as potential target against leishmaniasis. KEY POINTS: • Ld6PGDH enzymatic activity is competitively inhibited by gentamicin and cefuroxime. • It displays more helical contents and all structural characteristics of 6PGDH family. • Interaction studies demonstrate higher affinity of cofactor than substrate for Ld6PGDH.
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Affiliation(s)
- Pranay Jakkula
- Department of Biotechnology & Bioinformatics, School of Life Sciences, University of Hyderabad, Prof. C.R. Rao Road, Hyderabad, 500046, India
| | - Bandigi Narsimulu
- Department of Biotechnology & Bioinformatics, School of Life Sciences, University of Hyderabad, Prof. C.R. Rao Road, Hyderabad, 500046, India
| | - Insaf Ahmed Qureshi
- Department of Biotechnology & Bioinformatics, School of Life Sciences, University of Hyderabad, Prof. C.R. Rao Road, Hyderabad, 500046, India.
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5
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Morales-Luna L, Hernández-Ochoa B, Martínez-Rosas V, González-Valdez A, Cárdenas-Rodríguez N, Enríquez-Flores S, Marcial-Quino J, Gómez-Manzo S. Cloning, purification, and characterization of the 6-phosphogluconate dehydrogenase (6 PGDH) from Giardia lamblia. Mol Biochem Parasitol 2021; 244:111383. [PMID: 34048823 DOI: 10.1016/j.molbiopara.2021.111383] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 03/21/2021] [Accepted: 05/24/2021] [Indexed: 12/11/2022]
Abstract
Giardia lamblia, due to the habitat in which it develops, requires a continuous supply of intermediate compounds that allow it to survive in the host. The pentose phosphate pathway (PPP) provides essential molecules such as NADPH and ribulose-5-phosphate during the oxidative phase of the pathway. One of the key enzymes during this stage is 6-phosphogluconate dehydrogenase (6 PGDH) for generating NADPH. Given the relevance of the enzyme, in the present work, the 6pgdh gene from G. lamblia was amplified and cloned to produce the recombinant protein (Gl-6 PGDH) and characterize it functionally and structurally after the purification of Gl-6 PGDH by affinity chromatography. The results of the characterization showed that the protein has a molecular mass of 54 kDa, with an optimal pH of 7.0 and a temperature of 36-42 °C. The kinetic parameters of Gl-6 PGDH were Km = 49.2 and 139.9 μM (for NADP+ and 6-PG, respectively), Vmax =26.27 μmol*min-1*mg-1, and Kcat = 24.0 s-1. Finally, computational modeling studies were performed to obtain a structural visualization of the Gl-6 PGDH protein. The generation of the model and the characterization assays will allow us to expand our knowledge for future studies of the function of the protein in the metabolism of the parasite.
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Affiliation(s)
- Laura Morales-Luna
- Laboratorio de Bioquímica Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México, 04530, Mexico; Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México, 04510, Ciudad de México, Mexico
| | - Beatriz Hernández-Ochoa
- Laboratorio de Inmunoquímica, Hospital Infantil de México Federico Gómez, Secretaría de Salud, 06720, Ciudad de México, Mexico; Programa de Posgrado en Biomedicina y Biotecnología Molecular, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, 11340, Ciudad de México, Mexico
| | - Víctor Martínez-Rosas
- Laboratorio de Bioquímica Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México, 04530, Mexico; Programa de Posgrado en Biomedicina y Biotecnología Molecular, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, 11340, Ciudad de México, Mexico
| | - Abigail González-Valdez
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, 04510, Ciudad de México, Mexico
| | - Noemi Cárdenas-Rodríguez
- Laboratorio de Neurociencias, Instituto Nacional de Pediatría, Secretaría de Salud, 04530, Ciudad de México, Mexico
| | - Sergio Enríquez-Flores
- Grupo de Investigación en Biomoléculas y Salud Infantil, Laboratorio de EIMyT, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México, 04530, Mexico
| | - Jaime Marcial-Quino
- Investigador Independiente en Área de Salud, Ciudad de México, 03303, Mexico
| | - Saúl Gómez-Manzo
- Laboratorio de Bioquímica Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México, 04530, Mexico.
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6
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Maturana P, Tobar-Calfucoy E, Fuentealba M, Roversi P, Garratt R, Cabrera R. Crystal structure of the 6-phosphogluconate dehydrogenase from Gluconobacter oxydans reveals tetrameric 6PGDHs as the crucial intermediate in the evolution of structure and cofactor preference in the 6PGDH family. Wellcome Open Res 2021. [DOI: 10.12688/wellcomeopenres.16572.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Background: The enzyme 6-phosphogluconate dehydrogenase (6PGDH) is the central enzyme of the oxidative pentose phosphate pathway. Members of the 6PGDH family belong to different classes: either homodimeric enzymes assembled from long-chain subunits or homotetrameric ones assembled from short-chain subunits. Dimeric 6PGDHs bear an internal duplication absent in tetrameric 6PGDHs and distant homologues of the β-hydroxyacid dehydrogenase (βHADH) superfamily. Methods: We use X-ray crystallography to determine the structure of the apo form of the 6PGDH from Gluconobacter oxydans (Go6PGDH). We carried out a structural and phylogenetic analysis of short and long-chain 6PGDHs. We put forward an evolutionary hypothesis explaining the differences seen in oligomeric state vs. dinucleotide preference of the 6PGDH family. We determined the cofactor preference of Go6PGDH at different 6-phosphogluconate concentrations, characterizing the wild-type enzyme and three-point mutants of residues in the cofactor binding site of Go6PGDH. Results: The structural comparison suggests that the 6PG binding site initially evolved by exchanging C-terminal α-helices between subunits. An internal duplication event changed the quaternary structure of the enzyme from a tetrameric to a dimeric arrangement. The phylogenetic analysis suggests that 6PGDHs have spread from Bacteria to Archaea and Eukarya on multiple occasions by lateral gene transfer. Sequence motifs consistent with NAD+- and NADP+-specificity are found in the β2-α2 loop of dimeric and tetrameric 6PGDHs. Site-directed mutagenesis of Go6PGDH inspired by this analysis fully reverses dinucleotide preference. One of the mutants we engineered has the highest efficiency and specificity for NAD+ so far described for a 6PGDH. Conclusions: The family 6PGDH comprises dimeric and tetrameric members whose active sites are conformed by a C-terminal α-helix contributed from adjacent subunits. Dimeric 6PGDHs have evolved from the duplication-fusion of the tetrameric C-terminal domain before independent transitions of cofactor specificity. Changes in the conserved β2-α2 loop are crucial to modulate the cofactor specificity in Go6PGDH.
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7
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Omolabi KF, Odeniran PO, Olotu FA, S Soliman ME. A Mechanistic Probe into the Dual Inhibition of T. cruzi Glucokinase and Hexokinase in Chagas Disease Treatment - A Stone Killing Two Birds? Chem Biodivers 2021; 18:e2000863. [PMID: 33411971 DOI: 10.1002/cbdv.202000863] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Accepted: 01/07/2021] [Indexed: 01/15/2023]
Abstract
Glucokinase (GLK) and Hexokinase (HK) have been characterized as essential targets in Trypanosoma cruzi (Tc)-mediated infection. A recent study reported the propensity of the concomitant inhibition of TcGLK and TcHK by compounds GLK2-003 and GLK2-004, thereby presenting an efficient approach in Chagas disease treatment. We investigated this possibility using atomic and molecular scaling methods. Sequence alignment of TcGLK and TcHK revealed that both proteins shared approximately 33.3 % homology in their glucose/inhibitor binding sites. The total binding free energies of GLK2-003 and GLK2-004 were favorable in both proteins. PRO92 and THR185 were pivotal to the binding and stabilization of the ligands in TcGLK, likewise their conserved counterparts, PRO163 and THR237 in TcHK. Both compounds also induced a similar pattern of perturbations in both TcGLK and TcHK secondary structure. Findings from this study therefore provide insights into the underlying mechanisms of dual inhibition exhibited by the compounds. These results can pave way to discover and optimize novel dual Tc inhibitors with favorable pharmacokinetics properties eventuating in the mitigation of Chagas disease.
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Affiliation(s)
- Kehinde F Omolabi
- Molecular Bio-Computation and Drug Design Laboratory, School of Health Sciences, University of KwaZulu-Natal, Westville Campus, Durban, 4001, South Africa
| | - Paul O Odeniran
- Department of Veterinary Parasitology and Entomology, Faculty of Veterinary Medicine, University of Ibadan, Ibadan, 200001, Nigeria
| | - Fisayo A Olotu
- Molecular Bio-Computation and Drug Design Laboratory, School of Health Sciences, University of KwaZulu-Natal, Westville Campus, Durban, 4001, South Africa
| | - Mahmoud E S Soliman
- Molecular Bio-Computation and Drug Design Laboratory, School of Health Sciences, University of KwaZulu-Natal, Westville Campus, Durban, 4001, South Africa
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Ortíz C, Moraca F, Laverriere M, Jordan A, Hamilton N, Comini MA. Glucose 6-Phosphate Dehydrogenase from Trypanosomes: Selectivity for Steroids and Chemical Validation in Bloodstream Trypanosoma brucei. Molecules 2021; 26:E358. [PMID: 33445584 PMCID: PMC7826790 DOI: 10.3390/molecules26020358] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 01/07/2021] [Accepted: 01/09/2021] [Indexed: 11/17/2022] Open
Abstract
Glucose 6-phosphate dehydrogenase (G6PDH) fulfills an essential role in cell physiology by catalyzing the production of NADPH+ and of a precursor for the de novo synthesis of ribose 5-phosphate. In trypanosomatids, G6PDH is essential for in vitro proliferation, antioxidant defense and, thereby, drug resistance mechanisms. So far, 16α-brominated epiandrosterone represents the most potent hit targeting trypanosomal G6PDH. Here, we extended the investigations on this important drug target and its inhibition by using a small subset of androstane derivatives. In Trypanosoma cruzi, immunofluorescence revealed a cytoplasmic distribution of G6PDH and the absence of signal in major organelles. Cytochemical assays confirmed parasitic G6PDH as the molecular target of epiandrosterone. Structure-activity analysis for a set of new (dehydro)epiandrosterone derivatives revealed that bromination at position 16α of the cyclopentane moiety yielded more potent T. cruzi G6PDH inhibitors than the corresponding β-substituted analogues. For the 16α brominated compounds, the inclusion of an acetoxy group at position 3 either proved detrimental or enhanced the activity of the epiandrosterone or the dehydroepiandrosterone derivatives, respectively. Most derivatives presented single digit μM EC50 against infective T. brucei and the killing mechanism involved an early thiol-redox unbalance. This data suggests that infective African trypanosomes lack efficient NADPH+-synthesizing pathways, beyond the Pentose Phosphate, to maintain thiol-redox homeostasis.
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Affiliation(s)
- Cecilia Ortíz
- Redox Biology of Trypanosomes, Institut Pasteur de Montevideo, Mataojo 2020, Montevideo 11400, Uruguay;
| | - Francesca Moraca
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, Via Aldo Moro 2, 53100 Siena, Italy;
| | - Marc Laverriere
- Instituto de Investigaciones Biotecnológicas, Instituto Tecnológico de Chascomus (IIB-INTECH, UNSAM-CONICET), Av. General Paz 5445, INTI, San Martín 1650, Pcia de Buenos Aires, Argentina;
| | - Allan Jordan
- Drug Discovery Unit, Cancer Research UK Manchester Institute, University of Manchester, Alderley Park, Macclesfield SK10 4TG, UK; (A.J.); (N.H.)
| | - Niall Hamilton
- Drug Discovery Unit, Cancer Research UK Manchester Institute, University of Manchester, Alderley Park, Macclesfield SK10 4TG, UK; (A.J.); (N.H.)
| | - Marcelo A. Comini
- Redox Biology of Trypanosomes, Institut Pasteur de Montevideo, Mataojo 2020, Montevideo 11400, Uruguay;
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9
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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.
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10
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Cordeiro AT. NADPH Producing Enzymes as Promising Drug Targets for Chagas Disease. Curr Med Chem 2019; 26:6564-6571. [PMID: 30306853 DOI: 10.2174/0929867325666181009152844] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 09/10/2018] [Accepted: 09/19/2018] [Indexed: 11/22/2022]
Abstract
Reduced Nicotinamide Adenine Dinucleotide Phosphate (NADPH) is a cofactor used in different anabolic reactions, such as lipid and nucleic acid synthesis, and for oxidative stress defense. NADPH is essential for parasite growth and viability. In trypanosomatid parasites, NADPH is supplied by the oxidative branch of the pentose phosphate pathway and by enzymes associated with the citric acid cycle. The present article will review recent achievements that suggest glucose-6-phosphate dehydrogenase and the cytosolic isoform of the malic enzyme as promising drug targets for the discovery of new drugs against Trypanosoma cruzi and T. brucei. Topics involving an alternative strategy in accelerating T. cruzi drug-target validation and the concept of drug-target classification will also be revisited.
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Affiliation(s)
- Artur T Cordeiro
- Brazilian Bioscience National Laboratory, Brazilian Center for Research in Energy and Materials, Campinas- SP, Brazil
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11
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Glucose-6-Phosphate Dehydrogenase from the Human Pathogen Trypanosoma cruzi Evolved Unique Structural Features to Support Efficient Product Formation. J Mol Biol 2019; 431:2143-2162. [DOI: 10.1016/j.jmb.2019.03.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 03/04/2019] [Accepted: 03/24/2019] [Indexed: 12/25/2022]
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12
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Acosta H, Burchmore R, Naula C, Gualdrón-López M, Quintero-Troconis E, Cáceres AJ, Michels PAM, Concepción JL, Quiñones W. Proteomic analysis of glycosomes from Trypanosoma cruzi epimastigotes. Mol Biochem Parasitol 2019; 229:62-74. [PMID: 30831156 PMCID: PMC7082770 DOI: 10.1016/j.molbiopara.2019.02.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 02/25/2019] [Accepted: 02/27/2019] [Indexed: 12/20/2022]
Abstract
In Trypanosoma cruzi, the causal agent of Chagas disease, the first seven steps of glycolysis are compartmentalized in glycosomes, which are authentic but specialized peroxisomes. Besides glycolysis, activity of enzymes of other metabolic processes have been reported to be present in glycosomes, such as β-oxidation of fatty acids, purine salvage, pentose-phosphate pathway, gluconeogenesis and biosynthesis of ether-lipids, isoprenoids, sterols and pyrimidines. In this study, we have purified glycosomes from T. cruzi epimastigotes, collected the soluble and membrane fractions of these organelles, and separated peripheral and integral membrane proteins by Na2CO3 treatment and osmotic shock. Proteomic analysis was performed on each of these fractions, allowing us to confirm the presence of enzymes involved in various metabolic pathways as well as identify new components of this parasite's glycosomes.
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Affiliation(s)
- Héctor Acosta
- Laboratorio de Enzimología de Parásitos, Facultad de Ciencias, Universidad de Los Andes, Mérida, 5101, Venezuela
| | - Richard Burchmore
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Christina Naula
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Melisa Gualdrón-López
- Instituto Salud Global, Hospital Clinic-Universitat de Barcelona, and Institute for Health Sciences Trias i Pujol, Barcelona, Spain
| | - Ender Quintero-Troconis
- Laboratorio de Enzimología de Parásitos, Facultad de Ciencias, Universidad de Los Andes, Mérida, 5101, Venezuela
| | - Ana J Cáceres
- Laboratorio de Enzimología de Parásitos, Facultad de Ciencias, Universidad de Los Andes, Mérida, 5101, Venezuela
| | - Paul A M Michels
- Centre for Immunity, Infection and Evolution and Centre for Translational and Chemical Biology, The University of Edinburgh, Edinburgh, EH9 3FL, UK
| | - Juan Luis Concepción
- Laboratorio de Enzimología de Parásitos, Facultad de Ciencias, Universidad de Los Andes, Mérida, 5101, Venezuela
| | - Wilfredo Quiñones
- Laboratorio de Enzimología de Parásitos, Facultad de Ciencias, Universidad de Los Andes, Mérida, 5101, Venezuela.
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Haeussler K, Fritz-Wolf K, Reichmann M, Rahlfs S, Becker K. Characterization of Plasmodium falciparum 6-Phosphogluconate Dehydrogenase as an Antimalarial Drug Target. J Mol Biol 2018; 430:4049-4067. [DOI: 10.1016/j.jmb.2018.07.030] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 07/27/2018] [Accepted: 07/27/2018] [Indexed: 12/14/2022]
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Wachsmuth LM, Johnson MG, Gavenonis J. Essential multimeric enzymes in kinetoplastid parasites: A host of potentially druggable protein-protein interactions. PLoS Negl Trop Dis 2017; 11:e0005720. [PMID: 28662026 PMCID: PMC5507555 DOI: 10.1371/journal.pntd.0005720] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Revised: 07/12/2017] [Accepted: 06/16/2017] [Indexed: 12/18/2022] Open
Abstract
Parasitic diseases caused by kinetoplastid parasites of the genera Trypanosoma and Leishmania are an urgent public health crisis in the developing world. These closely related species possess a number of multimeric enzymes in highly conserved pathways involved in vital functions, such as redox homeostasis and nucleotide synthesis. Computational alanine scanning of these protein-protein interfaces has revealed a host of potentially ligandable sites on several established and emerging anti-parasitic drug targets. Analysis of interfaces with multiple clustered hotspots has suggested several potentially inhibitable protein-protein interactions that may have been overlooked by previous large-scale analyses focusing solely on secondary structure. These protein-protein interactions provide a promising lead for the development of new peptide and macrocycle inhibitors of these enzymes.
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Affiliation(s)
- Leah M. Wachsmuth
- Department of Chemistry, Dickinson College, Carlisle, Pennsylvania, United States of America
| | - Meredith G. Johnson
- Department of Chemistry, Dickinson College, Carlisle, Pennsylvania, United States of America
| | - Jason Gavenonis
- Department of Chemistry, Dickinson College, Carlisle, Pennsylvania, United States of America
- * E-mail:
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Gonzalez SN, Valsecchi WM, Maugeri D, Delfino JM, Cazzulo JJ. Structure, kinetic characterization and subcellular localization of the two ribulose 5-phosphate epimerase isoenzymes from Trypanosoma cruzi. PLoS One 2017; 12:e0172405. [PMID: 28207833 PMCID: PMC5312968 DOI: 10.1371/journal.pone.0172405] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 02/03/2017] [Indexed: 02/01/2023] Open
Abstract
The enzyme of the pentose phosphate pathway (PPP) ribulose-5-phosphate-epimerase (RPE) is encoded by two genes present in the genome of Trypanosoma cruzi CL Brener clone: TcRPE1 and TcRPE2. Despite high sequence similarity at the amino acid residue level, the recombinant isoenzymes show a strikingly different kinetics. Whereas TcRPE2 follows a typical michaelian behavior, TcRPE1 shows a complex kinetic pattern, displaying a biphasic curve, suggesting the coexistence of -at least- two kinetically different molecular forms. Regarding the subcellular localization in epimastigotes, whereas TcRPE1 is a cytosolic enzyme, TcRPE2 is localized in glycosomes. To our knowledge, TcRPE2 is the first PPP isoenzyme that is exclusively localized in glycosomes. Over-expression of TcRPE1, but not of TcRPE2, significantly reduces the parasite doubling time in vitro, as compared with wild type epimastigotes. Both TcRPEs represent single domain proteins exhibiting the classical α/β TIM-barrel fold, as expected for enzymes with this activity. With regard to the architecture of the active site, all the important amino acid residues for catalysis -with the exception of M58- are also present in both TcRPEs models. The superimposition of the binding pocket of both isoenzyme models shows that they adopt essentially identical positions in the active site with a residue specific RMSD < 2Å, with the sole exception of S12, which displays a large deviation (residue specific RMSD: 11.07 Å). Studies on the quaternary arrangement of these isoenzymes reveal that both are present in a mixture of various oligomeric species made up of an even number of molecules, probably pointing to the dimer as their minimal functional unit. This multiplicity of oligomeric species has not been reported for any of the other RPEs studied so far and it might bear implications for the regulation of TcRPEs activity, although further investigation will be necessary to unravel the physiological significance of these structural findings.
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Affiliation(s)
- Soledad Natalia Gonzalez
- Instituto de Investigaciones Biotecnológicas Dr. Rodolfo A. Ugalde-Instituto Tecnológico de Chascomús Dr. Raúl Alfonsín (IIB-INTECH), Universidad Nacional de San Martín (UNSAM)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Campus Miguelete, Buenos Aires, Argentina
| | - Wanda Mariela Valsecchi
- Instituto de Química y Fisicoquímica Biológicas, Universidad de Buenos Aires, Junín, Buenos Aires, Argentina
| | - Dante Maugeri
- Instituto de Investigaciones Biotecnológicas Dr. Rodolfo A. Ugalde-Instituto Tecnológico de Chascomús Dr. Raúl Alfonsín (IIB-INTECH), Universidad Nacional de San Martín (UNSAM)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Campus Miguelete, Buenos Aires, Argentina
| | - José María Delfino
- Instituto de Química y Fisicoquímica Biológicas, Universidad de Buenos Aires, Junín, Buenos Aires, Argentina
| | - Juan José Cazzulo
- Instituto de Investigaciones Biotecnológicas Dr. Rodolfo A. Ugalde-Instituto Tecnológico de Chascomús Dr. Raúl Alfonsín (IIB-INTECH), Universidad Nacional de San Martín (UNSAM)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Campus Miguelete, Buenos Aires, Argentina
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The Pentose Phosphate Pathway in Parasitic Trypanosomatids. Trends Parasitol 2016; 32:622-634. [DOI: 10.1016/j.pt.2016.04.010] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Revised: 04/11/2016] [Accepted: 04/13/2016] [Indexed: 12/20/2022]
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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.
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Igoillo-Esteve M, Maugeri D, Stern AL, Beluardi P, Cazzulo JJ. The pentose phosphate pathway in Trypanosoma cruzi: a potential target for the chemotherapy of Chagas disease. AN ACAD BRAS CIENC 2008; 79:649-63. [PMID: 18066434 DOI: 10.1590/s0001-37652007000400007] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2007] [Accepted: 08/17/2007] [Indexed: 11/21/2022] Open
Abstract
Trypanosoma cruzi is highly sensitive to oxidative stress caused by reactive oxygen species. Trypanothione, the parasite's major protection against oxidative stress, is kept reduced by trypanothione reductase, using NADPH; the major source of the reduced coenzyme seems to be the pentose phosphate pathway. Its seven enzymes are present in the four major stages in the parasite's biological cycle; we have cloned and expressed them in Escherichia coli as active proteins. Glucose 6-phosphate dehydrogenase, which controls glucose flux through the pathway by its response to the NADP/NADPH ratio, is encoded by a number of genes per haploid genome, and is induced up to 46-fold by hydrogen peroxide in metacyclic trypomastigotes. The genes encoding 6-phosphogluconolactonase, 6-phosphogluconate dehydrogenase, transaldolase and transketolase are present in the CL Brener clone as a single copy per haploid genome. 6-phosphogluconate dehydrogenase is very unstable, but was stabilized introducing two salt bridges by site-directed mutagenesis. Ribose-5-phosphate isomerase belongs to Type B; genes encoding Type A enzymes, present in mammals, are absent. Ribulose-5-phosphate epimerase is encoded by two genes. The enzymes of the pathway have a major cytosolic component, although several of them have a secondary glycosomal localization, and also minor localizations in other organelles.
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Affiliation(s)
- Mariana Igoillo-Esteve
- Instituto de Investigaciones Biotecnologicas, Instituto Tecnologico de Chascomus, Provincia de Buenos Aires, Argentina
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Cordeiro AT, Cáceres AJ, Vertommen D, Concepción JL, Michels PAM, Versées W. The crystal structure of Trypanosoma cruzi glucokinase reveals features determining oligomerization and anomer specificity of hexose-phosphorylating enzymes. J Mol Biol 2007; 372:1215-26. [PMID: 17761195 DOI: 10.1016/j.jmb.2007.07.021] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2007] [Revised: 07/06/2007] [Accepted: 07/11/2007] [Indexed: 11/30/2022]
Abstract
Glucose is an essential substrate for Trypanosoma cruzi, the protozoan organism responsible for Chagas' disease. The glucose is intracellularly phosphorylated to glucose 6-phosphate. Previously, a hexokinase responsible for this phosphorylation has been characterized. Recently, we identified an ATP-dependent glucokinase in T. cruzi exhibiting a tenfold lower substrate affinity compared to the hexokinase. Both enzymes, which belong to very different groups of the same family, are located inside glycosomes, the peroxisome-like organelles of Kinetoplastida that are known to contain the first seven glycolytic steps as well as enzymes of the oxidative branch of the pentose phosphate pathway. Here, we present the crystallographic structure of T. cruzi glucokinase, in complex with glucose and ADP. The structure suggests a loose tetrameric assembly formed by the association of two tight dimers. TcGlcK was previously reported to exist in a concentration-dependent equilibrium of monomeric and dimeric states. Here, we used mass spectrometry analysis to confirm the existence of TcGlcK monomeric and dimeric states. The analysis of subunit interactions and comparison with the bacterial glucokinases give insights into the forces promoting the stability of the different oligomeric states. Each T. cruzi glucokinase monomer contains one glucose and one ADP molecule. In contrast to hexokinases, which show a moderate preference for the alpha anomer of glucose, the electron density clearly shows the d-glucose bound in the beta configuration in the T.cruzi glucokinase. Kinetic assays with alpha and beta-d-glucose further confirm a moderate preference of the T. cruzi glucokinase for the beta anomer. Structural comparison of the glucokinase and hexokinases permits the identification of a possible mechanism for anomer selectivity in these hexose-phosphorylating enzymes. The preference for distinct anomers suggests that in T. cruzi hexokinase and glucokinase are not directly competing for the same substrate and are probably both present because they exert distinct physiological functions.
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Affiliation(s)
- Artur T Cordeiro
- Research Unit for Tropical Diseases, Christian de Duve Institute of Cellular Pathology, Avenue Hippocrate 74, B-1200 Brussels, Belgium
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