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Soprano LL, Ferrero MR, Jacobs T, Couto AS, Duschak VG. Hallmarks of the relationship between host and Trypanosoma cruzi sulfated glycoconjugates along the course of Chagas disease. Front Cell Infect Microbiol 2023; 13:1028496. [PMID: 37256110 PMCID: PMC10225527 DOI: 10.3389/fcimb.2023.1028496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 04/17/2023] [Indexed: 06/01/2023] Open
Abstract
American Trypanosomiasis or Chagas disease (ChD), a major problem that is still endemic in large areas of Latin America, is caused by Trypanosoma cruzi. This agent holds a major antigen, cruzipain (Cz). Its C-terminal domain (C-T) is retained in the glycoprotein mature form and bears several post-translational modifications. Glycoproteins containing sulfated N-linked oligosaccharides have been mostly implicated in numerous specific procedures of molecular recognition. The presence of sulfated oligosaccharides was demonstrated in Cz, also in a minor abundant antigen with serine-carboxypeptidase (SCP) activity, as well as in parasite sulfatides. Sulfate-bearing glycoproteins in Trypanosomatids are targets of specific immune responses. T. cruzi chronically infected subjects mount specific humoral immune responses to sulfated Cz. Unexpectedly, in the absence of infection, mice immunized with C-T, but not with sulfate-depleted C-T, showed ultrastructural heart anomalous pathological effects. Moreover, the synthetic anionic sugar conjugate GlcNAc6SO3-BSA showed to mimic the N-glycan-linked sulfated epitope (sulfotope) humoral responses that natural Cz elicits. Furthermore, it has been reported that sulfotopes participate via the binding of sialic acid Ig-like-specific lectins (Siglecs) to sulfosialylated glycoproteins in the immunomodulation by host-parasite interaction as well as in the parasite infection process. Strikingly, recent evidence involved Cz-sulfotope-specific antibodies in the immunopathogenesis and infection processes during the experimental ChD. Remarkably, sera from chronically T. cruzi-infected individuals with mild disease displayed higher levels of IgG2 antibodies specific for sulfated glycoproteins and sulfatides than those with more severe forms of the disease, evidencing that T. cruzi sulfotopes are antigenic independently of the sulfated glycoconjugate type. Ongoing assays indicate that antibodies specific for sulfotopes might be considered biomarkers of human cardiac ChD progression, playing a role as predictors of stability from the early mild stages of chronic ChD.
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Affiliation(s)
- Luciana L. Soprano
- Area of Protein Biochemistry and Parasite Glycobiology, Research Department National Institute of Parasitology (INP)”Dr. Mario Fatala Chaben”, National Administration of Health Institutes (ANLIS)-Malbrán, National Health Department, National Council of Scientific and Technical Research (CONICET), Buenos Aires, Argentina
| | - Maximiliano R. Ferrero
- Max-Planck Heart and Lung Laboratory, Research Institute in Biomedicine in Buenos Aires (IBioBA), Argentine-Department of Internal Medicine II, University Medical Center Giessen and Marburg, Giessen, Germany
| | - Thomas Jacobs
- Immunology Department, Bernhard Notch Institute of Tropical Medicine, Hamburg, Germany
| | - Alicia S. Couto
- Faculty in Exact and Natural Sciences (FCEN), Chemical Organic Department-National Council of Scientific and Technical Research (CONICET), Center of CarboHydrates (CHIHIDECAR), University of Buenos Aires, Buenos Aires, Argentina
| | - Vilma G. Duschak
- Area of Protein Biochemistry and Parasite Glycobiology, Research Department National Institute of Parasitology (INP)”Dr. Mario Fatala Chaben”, National Administration of Health Institutes (ANLIS)-Malbrán, National Health Department, National Council of Scientific and Technical Research (CONICET), Buenos Aires, Argentina
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Brogi S, Ibba R, Rossi S, Butini S, Calderone V, Gemma S, Campiani G. Covalent Reversible Inhibitors of Cysteine Proteases Containing the Nitrile Warhead: Recent Advancement in the Field of Viral and Parasitic Diseases. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27082561. [PMID: 35458759 PMCID: PMC9029279 DOI: 10.3390/molecules27082561] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 04/08/2022] [Accepted: 04/13/2022] [Indexed: 12/29/2022]
Abstract
In the field of drug discovery, the nitrile group is well represented among drugs and biologically active compounds. It can form both non-covalent and covalent interactions with diverse biological targets, and it is amenable as an electrophilic warhead for covalent inhibition. The main advantage of the nitrile group as a warhead is mainly due to its milder electrophilic character relative to other more reactive groups (e.g., -CHO), reducing the possibility of unwanted reactions that would hinder the development of safe drugs, coupled to the ease of installation through different synthetic approaches. The covalent inhibition is a well-assessed design approach for serine, threonine, and cysteine protease inhibitors. The mechanism of hydrolysis of these enzymes involves the formation of a covalent acyl intermediate, and this mechanism can be exploited by introducing electrophilic warheads in order to mimic this covalent intermediate. Due to the relevant role played by the cysteine protease in the survival and replication of infective agents, spanning from viruses to protozoan parasites, we will review the most relevant and recent examples of protease inhibitors presenting a nitrile group that have been introduced to form or to facilitate the formation of a covalent bond with the catalytic cysteine active site residue.
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Affiliation(s)
- Simone Brogi
- Department of Pharmacy, University of Pisa, Via Bonanno 6, 56126 Pisa, Italy; (S.B.); (V.C.)
| | - Roberta Ibba
- Department of Biotechnology, Chemistry and Pharmacy, DoE Department of Excellence 2018-2022, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; (R.I.); (S.R.); (S.B.); (G.C.)
| | - Sara Rossi
- Department of Biotechnology, Chemistry and Pharmacy, DoE Department of Excellence 2018-2022, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; (R.I.); (S.R.); (S.B.); (G.C.)
| | - Stefania Butini
- Department of Biotechnology, Chemistry and Pharmacy, DoE Department of Excellence 2018-2022, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; (R.I.); (S.R.); (S.B.); (G.C.)
| | - Vincenzo Calderone
- Department of Pharmacy, University of Pisa, Via Bonanno 6, 56126 Pisa, Italy; (S.B.); (V.C.)
| | - Sandra Gemma
- Department of Biotechnology, Chemistry and Pharmacy, DoE Department of Excellence 2018-2022, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; (R.I.); (S.R.); (S.B.); (G.C.)
- Correspondence:
| | - Giuseppe Campiani
- Department of Biotechnology, Chemistry and Pharmacy, DoE Department of Excellence 2018-2022, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; (R.I.); (S.R.); (S.B.); (G.C.)
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Yoon KA, Kim WJ, Lee S, Yang HS, Lee BH, Lee SH. Comparative analyses of the venom components in the salivary gland transcriptomes and saliva proteomes of some heteropteran insects. INSECT SCIENCE 2022; 29:411-429. [PMID: 34296820 DOI: 10.1111/1744-7917.12955] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 07/16/2021] [Accepted: 07/19/2021] [Indexed: 06/13/2023]
Abstract
Salivary gland-specific transcriptomes of nine heteropteran insects with distinct feeding strategies (predaceous, hematophagous, and phytophagous) were analyzed and annotated to compare and identify the venom components as well as their expression profiles. The transcriptional abundance of venom genes was verified via quantitative real-time PCR. Hierarchical clustering of 30 representative differentially expressed venom genes from the nine heteropteran species revealed unique groups of salivary gland-specific genes depending on their feeding strategy. The commonly transcribed genes included a paralytic neurotoxin (arginine kinase), digestive enzymes (cathepsin and serine protease), an anti-inflammatory protein (cystatin), hexamerin, and an odorant binding protein. Both predaceous and hematophagous (bed bug) heteropteran species showed relatively higher transcription levels of genes encoding proteins involved in proteolysis and cytolysis, whereas phytophagous heteropterans exhibited little or no expression of these genes, but had a high expression of vitellogenin, a multifunctional allergen. Saliva proteomes from four representative species were also analyzed. All venom proteins identified via saliva proteome analysis were annotated using salivary gland transcriptome data. The proteomic expression profiles of venom proteins were in good agreement with the salivary gland-specific transcriptomic profiles. Our results indicate that profiling of the salivary gland transcriptome provides important information on the composition and evolutionary features of venoms depending on their feeding strategy.
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Affiliation(s)
- Kyungjae Andrew Yoon
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, Korea
| | | | - Seungki Lee
- National Institute of Biological Resources, Environmental Research Complex, Incheon, Korea
| | - Hee-Sun Yang
- National Institute of Biological Resources, Environmental Research Complex, Incheon, Korea
| | - Byoung-Hee Lee
- National Institute of Biological Resources, Environmental Research Complex, Incheon, Korea
| | - Si Hyeock Lee
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, Korea
- Department of Agricultural Biology, Seoul National University, Seoul, Korea
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Vieira RP, Santos VC, Ferreira RS. Structure-based Approaches Targeting Parasite Cysteine Proteases. Curr Med Chem 2019; 26:4435-4453. [PMID: 28799498 DOI: 10.2174/0929867324666170810165302] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 07/18/2017] [Accepted: 07/18/2017] [Indexed: 12/17/2022]
Abstract
Cysteine proteases are essential hydrolytic enzymes present in the majority of organisms, including viruses and unicellular parasites. Despite the high sequence identity displayed among these proteins, specific structural features across different species grant distinct functions to these biomolecules, frequently related to pathological conditions. Consequently, their relevance as promising targets for potential specific inhibitors has been highlighted and occasionally validated in recent decades. In this review, we discuss the recent outcomes of structure-based campaigns aiming the discovery of new inhibitor prototypes against cruzain and falcipain, as alternative therapeutic tools for Chagas disease and malaria treatments, respectively. Computational and synthetic approaches have been combined on hit optimization strategies and are also discussed herein. These rationales are extended to additional tropical infectious and neglected pathologies, such as schistosomiasis, leishmaniasis and babesiosis, and also to Alzheimer's Disease, a widespread neurodegenerative disease poorly managed by currently available drugs and recently linked to particular physiopathological roles of human cysteine proteases.
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Affiliation(s)
- Rafael Pinto Vieira
- Departamento de Bioquimica e Imunologia, Instituto de Ciencias Biologicas, Universidade Federal de Minas Gerais, 31270-901 Belo Horizonte, MG, Brazil.,CAPES Foundation, Ministry of Education of Brazil, 70040-020 Brasília, DF, Brazil
| | - Viviane Corrêa Santos
- Departamento de Bioquimica e Imunologia, Instituto de Ciencias Biologicas, Universidade Federal de Minas Gerais, 31270-901 Belo Horizonte, MG, Brazil
| | - Rafaela Salgado Ferreira
- Departamento de Bioquimica e Imunologia, Instituto de Ciencias Biologicas, Universidade Federal de Minas Gerais, 31270-901 Belo Horizonte, MG, Brazil
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Boudreau PD, Miller BW, McCall LI, Almaliti J, Reher R, Hirata K, Le T, Siqueira-Neto JL, Hook V, Gerwick WH. Design of Gallinamide A Analogs as Potent Inhibitors of the Cysteine Proteases Human Cathepsin L and Trypanosoma cruzi Cruzain. J Med Chem 2019; 62:9026-9044. [PMID: 31539239 DOI: 10.1021/acs.jmedchem.9b00294] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Gallinamide A, originally isolated with a modest antimalarial activity, was subsequently reisolated and characterized as a potent, selective, and irreversible inhibitor of the human cysteine protease cathepsin L. Molecular docking identified potential modifications to improve binding, which were synthesized as a suite of analogs. Resultingly, this current study produced the most potent gallinamide analog yet tested against cathepsin L (10, Ki = 0.0937 ± 0.01 nM and kinact/Ki = 8 730 000). From a protein structure and substrate preference perspective, cruzain, an essential Trypanosoma cruzi cysteine protease, is highly homologous. Our investigations revealed that gallinamide and its analogs potently inhibit cruzain and are exquisitely toxic toward T. cruzi in the intracellular amastigote stage. The most active compound, 5, had an IC50 = 5.1 ± 1.4 nM, but was relatively inactive to both the epimastigote (insect stage) and the host cell, and thus represents a new candidate for the treatment of Chagas disease.
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Affiliation(s)
| | | | | | - Jehad Almaliti
- Department of Pharmaceutical Sciences, College of Pharmacy , The University of Jordan , Amman 11942 , Jordan
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Siqueira-Neto JL, Debnath A, McCall LI, Bernatchez JA, Ndao M, Reed SL, Rosenthal PJ. Cysteine proteases in protozoan parasites. PLoS Negl Trop Dis 2018; 12:e0006512. [PMID: 30138453 PMCID: PMC6107107 DOI: 10.1371/journal.pntd.0006512] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Cysteine proteases (CPs) play key roles in the pathogenesis of protozoan parasites, including cell/tissue penetration, hydrolysis of host or parasite proteins, autophagy, and evasion or modulation of the host immune response, making them attractive chemotherapeutic and vaccine targets. This review highlights current knowledge on clan CA cysteine proteases, the best-characterized group of cysteine proteases, from 7 protozoan organisms causing human diseases with significant impact: Entamoeba histolytica, Leishmania species (sp.), Trypanosoma brucei, T. cruzi, Cryptosporidium sp., Plasmodium sp., and Toxoplasma gondii. Clan CA proteases from three organisms (T. brucei, T. cruzi, and Plasmodium sp.) are well characterized as druggable targets based on in vitro and in vivo models. A number of candidate inhibitors are under development. CPs from these organisms and from other protozoan parasites should be further characterized to improve our understanding of their biological functions and identify novel targets for chemotherapy.
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Affiliation(s)
- Jair L. Siqueira-Neto
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, United States of America
- * E-mail:
| | - Anjan Debnath
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, United States of America
| | - Laura-Isobel McCall
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, United States of America
| | - Jean A. Bernatchez
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, United States of America
| | - Momar Ndao
- National Reference Centre for Parasitology, The Research Institute of the McGill University Health Center, Montreal, Canada
- Program in Infectious Diseases and Immunity in Global Health, The Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
| | - Sharon L. Reed
- Departments of Pathology and Medicine, University of California San Diego School of Medicine, La Jolla, California, United States of America
| | - Philip J. Rosenthal
- Department of Medicine, University of California, San Francisco, San Francisco, California, United States of America
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Moreira CMDN, Batista CM, Fernandes JC, Kessler RL, Soares MJ, Fragoso SP. Knockout of the gamma subunit of the AP-1 adaptor complex in the human parasite Trypanosoma cruzi impairs infectivity and differentiation and prevents the maturation and targeting of the major protease cruzipain. PLoS One 2017; 12:e0179615. [PMID: 28759609 PMCID: PMC5536268 DOI: 10.1371/journal.pone.0179615] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 05/31/2017] [Indexed: 11/18/2022] Open
Abstract
The AP-1 Adaptor Complex assists clathrin-coated vesicle assembly in the trans-Golgi network (TGN) of eukaryotic cells. However, the role of AP-1 in the protozoan Trypanosoma cruzi-the Chagas disease parasite-has not been addressed. Here, we studied the function and localization of AP-1 in different T. cruzi life cycle forms, by generating a gene knockout of the large AP-1 subunit gamma adaptin (TcAP1-γ), and raising a monoclonal antibody against TcAP1-γ. Co-localization with a Golgi marker and with the clathrin light chain showed that TcAP1-γ is located in the Golgi, and it may interact with clathrin in vivo, at the TGN. Epimastigote (insect form) parasites lacking TcAP1-γ (TcγKO) have reduced proliferation and differentiation into infective metacyclic trypomastigotes (compared with wild-type parasites). TcγKO parasites have also displayed significantly reduced infectivity towards mammalian cells. Importantly, TcAP1-γ knockout impaired maturation and transport to lysosome-related organelles (reservosomes) of a key cargo-the major cysteine protease cruzipain, which is important for parasite nutrition, differentiation and infection. In conclusion, the defective processing and transport of cruzipain upon AP-1 ablation may underlie the phenotype of TcγKO parasites.
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Affiliation(s)
| | | | | | - Rafael Luis Kessler
- Laboratory of Functional Genomics. Instituto Carlos Chagas/Fiocruz, Curitiba - PR, Brazil
| | - Maurilio José Soares
- Laboratory of Cell Biology, Instituto Carlos Chagas/Fiocruz, Curitiba - PR, Brazil
| | - Stenio Perdigão Fragoso
- Laboratory of Molecular Biology of Trypanosomatids, Instituto Carlos Chagas/Fiocruz, Curitiba - PR, Brazil
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Arafet K, Ferrer S, Moliner V. First quantum mechanics/molecular mechanics studies of the inhibition mechanism of cruzain by peptidyl halomethyl ketones. Biochemistry 2015; 54:3381-91. [PMID: 25965914 DOI: 10.1021/bi501551g] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Cruzain is a primary cysteine protease expressed by the protozoan parasite Trypanosoma cruzi during Chagas disease infection, and thus, the development of inhibitors of this protein is a promising target for designing an effective therapy against the disease. In this paper, the mechanism of inhibition of cruzain by two different irreversible peptidyl halomethyl ketones (PHK) inhibitors has been studied by means of hybrid quantum mechanics/molecular mechanics-molecular dynamics (MD) simulations to obtain a complete representation of the possible free energy reaction paths. These have been traced on free energy surfaces in terms of the potential of mean force computed at AM1d/MM and DFT/MM levels of theory. An analysis of the possible reaction mechanisms of the inhibition process has been performed showing that the nucleophilic attack of an active site cysteine, Cys25, on a carbon atom of the inhibitor and the cleavage of the halogen-carbon bond take place in a single step. PClK appears to be much more favorable than PFK from a kinetic point of view. This result would be in agreement with experimental studies in other papain-like enzymes. A deeper analysis of the results suggests that the origin of the differences between PClK and PFK can be the different stabilizing interactions established between the inhibitors and the residues of the active site of the protein. Any attempt to explore the viability of the inhibition process through a stepwise mechanism involving the formation of a thiohemiketal intermediate and a three-membered sulfonium intermediate has been unsuccessful. Nevertheless, a mechanism through a protonated thiohemiketal, with participation of His159 as a proton donor, appears to be feasible despite showing higher free energy barriers. Our results suggest that PClK can be used as a starting point to develop a proper inhibitor of cruzain.
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Affiliation(s)
- Kemel Arafet
- Departament de Química Física i Analítica, Universitat Jaume I, 12071 Castelló, Spain
| | - Silvia Ferrer
- Departament de Química Física i Analítica, Universitat Jaume I, 12071 Castelló, Spain
| | - Vicent Moliner
- Departament de Química Física i Analítica, Universitat Jaume I, 12071 Castelló, Spain
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Alves LR, Guerra-Slompo EP, de Oliveira AV, Malgarin JS, Goldenberg S, Dallagiovanna B. mRNA localization mechanisms in Trypanosoma cruzi. PLoS One 2013; 8:e81375. [PMID: 24324687 PMCID: PMC3852752 DOI: 10.1371/journal.pone.0081375] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Accepted: 10/13/2013] [Indexed: 01/06/2023] Open
Abstract
Asymmetric mRNA localization is a sophisticated tool for regulating and optimizing protein synthesis and maintaining cell polarity. Molecular mechanisms involved in the regulated localization of transcripts are widespread in higher eukaryotes and fungi, but not in protozoa. Trypanosomes are ancient eukaryotes that branched off early in eukaryote evolution. We hypothesized that these organisms would have basic mechanisms of mRNA localization. FISH assays with probes against transcripts coding for proteins with restricted distributions showed a discrete localization of the mRNAs in the cytoplasm. Moreover, cruzipain mRNA was found inside reservosomes suggesting new unexpected functions for this vacuolar organelle. Individual mRNAs were also mobilized to RNA granules in response to nutritional stress. The cytoplasmic distribution of these transcripts changed with cell differentiation, suggesting that localization mechanisms might be involved in the regulation of stage-specific protein expression. Transfection assays with reporter genes showed that, as in higher eukaryotes, 3'UTRs were responsible for guiding mRNAs to their final location. Our results strongly suggest that Trypanosoma cruzi have a core, basic mechanism of mRNA localization. This kind of controlled mRNA transport is ancient, dating back to early eukaryote evolution.
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Affiliation(s)
- Lysangela R. Alves
- Laboratório de Regulação da Expressão Gênica, Instituto Carlos Chagas, Fiocruz-Paraná. Curitiba, Paraná, Brasil
| | - Eloise P. Guerra-Slompo
- Laboratório de Regulação da Expressão Gênica, Instituto Carlos Chagas, Fiocruz-Paraná. Curitiba, Paraná, Brasil
| | - Arthur V. de Oliveira
- Laboratório de Regulação da Expressão Gênica, Instituto Carlos Chagas, Fiocruz-Paraná. Curitiba, Paraná, Brasil
| | - Juliane S. Malgarin
- Laboratório de Regulação da Expressão Gênica, Instituto Carlos Chagas, Fiocruz-Paraná. Curitiba, Paraná, Brasil
| | - Samuel Goldenberg
- Laboratório de Regulação da Expressão Gênica, Instituto Carlos Chagas, Fiocruz-Paraná. Curitiba, Paraná, Brasil
| | - Bruno Dallagiovanna
- Laboratório de Regulação da Expressão Gênica, Instituto Carlos Chagas, Fiocruz-Paraná. Curitiba, Paraná, Brasil
- * E-mail:
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Brennand A, Rico E, Michels PAM. Autophagy in trypanosomatids. Cells 2012; 1:346-71. [PMID: 24710480 PMCID: PMC3901119 DOI: 10.3390/cells1030346] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Revised: 07/14/2012] [Accepted: 07/16/2012] [Indexed: 01/07/2023] Open
Abstract
Autophagy is a ubiquitous eukaryotic process that also occurs in trypanosomatid parasites, protist organisms belonging to the supergroup Excavata, distinct from the supergroup Opistokontha that includes mammals and fungi. Half of the known yeast and mammalian AuTophaGy (ATG) proteins were detected in trypanosomatids, although with low sequence conservation. Trypanosomatids such as Trypanosoma brucei, Trypanosoma cruzi and Leishmania spp. are responsible for serious tropical diseases in humans. The parasites are transmitted by insects and, consequently, have a complicated life cycle during which they undergo dramatic morphological and metabolic transformations to adapt to the different environments. Autophagy plays a major role during these transformations. Since inhibition of autophagy affects the transformation, survival and/or virulence of the parasites, the ATGs offer promise for development of drugs against tropical diseases. Furthermore, various trypanocidal drugs have been shown to trigger autophagy-like processes in the parasites. It is inferred that autophagy is used by the parasites in an-not always successful-attempt to cope with the stress caused by the toxic compounds.
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Affiliation(s)
- Ana Brennand
- Research Unit for Tropical Diseases, de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 74, postal box B1.74.01, B-1200 Brussels, Belgium.
| | - Eva Rico
- Department of Biochemistry and Molecular Biology, University Campus, University of Alcalá, Alcalá de Henares, Madrid, 28871, Spain.
| | - Paul A M Michels
- Research Unit for Tropical Diseases, de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 74, postal box B1.74.01, B-1200 Brussels, Belgium.
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Ferrão PM, de Oliveira FL, Degrave WM, Araujo-Jorge TC, Mendonça-Lima L, Waghabi MC. A phosphoproteomic approach towards the understanding of the role of TGF-β in Trypanosoma cruzi biology. PLoS One 2012; 7:e38736. [PMID: 22719930 PMCID: PMC3373645 DOI: 10.1371/journal.pone.0038736] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2012] [Accepted: 05/09/2012] [Indexed: 01/06/2023] Open
Abstract
Transforming growth factor beta (TGF-β) plays a pivotal role in Chagas disease, not only in the development of chagasic cardiomyopathy, but also in many stages of the T. cruzi life cycle and survival in the host cell environment. The intracellular signaling pathways utilized by T. cruzi to regulate these mechanisms remain unknown. To identify parasite proteins involved in the TGF-β response, we utilized a combined approach of two-dimensional gel electrophoresis (2DE) analysis and mass spectrometry (MS) protein identification. Signaling via TGF-β is dependent on events of phosphorylation, which is one of the most relevant and ubiquitous post-translational modifications for the regulation of gene expression, and especially in trypanosomatids, since they lack several transcriptional control mechanisms. Here we show a kinetic view of T. cruzi epimastigotes (Y strain) incubated with TGF-β for 1, 5, 30 and 60 minutes, which promoted a remodeling of the parasite phosphorylation network and protein expression pattern. The altered molecules are involved in a variety of cellular processes, such as proteolysis, metabolism, heat shock response, cytoskeleton arrangement, oxidative stress regulation, translation and signal transduction. A total of 75 protein spots were up- or down-regulated more than twofold after TGF-β treatment, and from these, 42 were identified by mass spectrometry, including cruzipain-the major T. cruzi papain-like cysteine proteinase that plays an important role in invasion and participates in the escape mechanisms used by the parasite to evade the host immune system. In our study, we observed that TGF-β addition favored epimastigote proliferation, corroborating 2DE data in which proteins previously described to be involved in this process were positively stimulated by TGF-β.
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Affiliation(s)
- Patrícia M. Ferrão
- Laboratório de Genômica Funcional e Bioinformática, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Fabiane L. de Oliveira
- Laboratório de Genômica Funcional e Bioinformática, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Wim M. Degrave
- Laboratório de Genômica Funcional e Bioinformática, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Tania C. Araujo-Jorge
- Laboratório de Inovações em Terapias, Ensino e Bioprodutos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Leila Mendonça-Lima
- Laboratório de Genômica Funcional e Bioinformática, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
- * E-mail: (LM-L); (MCW)
| | - Mariana C. Waghabi
- Laboratório de Genômica Funcional e Bioinformática, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
- * E-mail: (LM-L); (MCW)
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Repertoire, genealogy and genomic organization of cruzipain and homologous genes in Trypanosoma cruzi, T. cruzi-like and other trypanosome species. PLoS One 2012; 7:e38385. [PMID: 22685565 PMCID: PMC3369871 DOI: 10.1371/journal.pone.0038385] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2011] [Accepted: 05/04/2012] [Indexed: 12/29/2022] Open
Abstract
Trypanosoma cruzi, the agent of Chagas disease, is a complex of genetically diverse isolates highly phylogenetically related to T. cruzi-like species, Trypanosoma cruzi marinkellei and Trypanosoma dionisii, all sharing morphology of blood and culture forms and development within cells. However, they differ in hosts, vectors and pathogenicity: T. cruzi is a human pathogen infective to virtually all mammals whilst the other two species are non-pathogenic and bat restricted. Previous studies suggest that variations in expression levels and genetic diversity of cruzipain, the major isoform of cathepsin L-like (CATL) enzymes of T. cruzi, correlate with levels of cellular invasion, differentiation, virulence and pathogenicity of distinct strains. In this study, we compared 80 sequences of genes encoding cruzipain from 25 T. cruzi isolates representative of all discrete typing units (DTUs TcI-TcVI) and the new genotype Tcbat and 10 sequences of homologous genes from other species. The catalytic domain repertoires diverged according to DTUs and trypanosome species. Relatively homogeneous sequences are found within and among isolates of the same DTU except TcV and TcVI, which displayed sequences unique or identical to those of TcII and TcIII, supporting their origin from the hybridization between these two DTUs. In network genealogies, sequences from T. cruzi clustered tightly together and closer to T. c. marinkellei than to T. dionisii and largely differed from homologues of T. rangeli and T. b. brucei. Here, analysis of isolates representative of the overall biological and genetic diversity of T. cruzi and closest T. cruzi-like species evidenced DTU- and species-specific polymorphisms corroborating phylogenetic relationships inferred with other genes. Comparison of both phylogenetically close and distant trypanosomes is valuable to understand host-parasite interactions, virulence and pathogenicity. Our findings corroborate cruzipain as valuable target for drugs, vaccine, diagnostic and genotyping approaches.
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13
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Garrido VV, Dulgerian LR, Stempin CC, Cerbán FM. The increase in mannose receptor recycling favors arginase induction and Trypanosoma cruzi survival in macrophages. Int J Biol Sci 2011; 7:1257-72. [PMID: 22110379 PMCID: PMC3221363 DOI: 10.7150/ijbs.7.1257] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Accepted: 10/01/2011] [Indexed: 01/10/2023] Open
Abstract
The macrophage mannose receptor (MR) is a pattern recognition receptor of the innate immune system that binds to microbial structures bearing mannose, fucose and N-acetylglucosamine on their surface. Trypanosoma cruzi antigen cruzipain (Cz) is found in the different developmental forms of the parasite. This glycoprotein has a highly mannosylated C-terminal domain that participates in the host-antigen contact. Our group previously demonstrated that Cz-macrophage (Mo) interaction could modulate the immune response against T. cruzi through the induction of a preferential metabolic pathway. In this work, we have studied in Mo the role of MR in arginase induction and in T. cruzi survival using different MR ligands. We have showed that pre-incubation of T. cruzi infected cells with mannose-Bovine Serum Albumin (Man-BSA, MR specific ligand) biased nitric oxide (NO)/urea balance towards urea production and increased intracellular amastigotes growth. The study of intracellular signals showed that pre-incubation with Man-BSA in T. cruzi J774 infected cells induced down-regulation of JNK and p44/p42 phosphorylation and increased of p38 MAPK phosphorylation. These results are coincident with previous data showing that Cz also modifies the MAPK phosphorylation profile induced by the parasite. In addition, we have showed by confocal microscopy that Cz and Man-BSA enhance MR recycling. Furthermore, we studied MR behavior during T. cruzi infection in vivo. MR was up-regulated in F4/80+ cells from T. cruzi infected mice at 13 and 15 days post infection. Besides, we investigated the effect of MR blocking antibody in T. cruzi infected peritoneal Mo. Arginase activity and parasite growth were decreased in infected cells pre-incubated with anti-MR antibody as compared with infected cells treated with control antibody. Therefore, we postulate that during T. cruzi infection, Cz may contact with MR, increasing MR recycling which leads to arginase activity up-regulation and intracellular parasite growth.
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Affiliation(s)
- Vanina V Garrido
- CIBICI-CONICET, Dpto Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
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14
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Tastan Bishop O, Kroon M. Study of protein complexes via homology modeling, applied to cysteine proteases and their protein inhibitors. J Mol Model 2011; 17:3163-72. [PMID: 21365221 DOI: 10.1007/s00894-011-0990-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2010] [Accepted: 01/24/2011] [Indexed: 11/29/2022]
Abstract
This paper develops and evaluates large-scale calculation of 3D structures of protein complexes by homology modeling as a promising new approach for protein docking. The complexes investigated were papain-like cysteine proteases and their protein inhibitors, which play numerous roles in human and parasitic metabolisms. The structural modeling was performed in two parts. For the first part (evaluation set), nine crystal structure complexes were selected, 1325 homology models of known complexes were rebuilt by various templates including hybrids, allowing an analysis of the factors influencing the accuracy of the models. The important considerations for modeling the interface were protease coverage and inhibitor sequence identity. In the second part (study set), the findings of the evaluation set were used to select appropriate templates to model novel cysteine protease-inhibitor complexes from human and malaria parasites Plasmodium falciparum and Plasmodium vivax. The energy scores, considering the evaluation set, indicate that the models are of high accuracy.
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Affiliation(s)
- Ozlem Tastan Bishop
- Rhodes University Bioinformatics (RUBi), Department of Biochemistry, Microbiology and Biotechnology, Rhodes University, Grahamstown 6140, South Africa.
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15
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Duszenko M, Ginger ML, Brennand A, Gualdrón-López M, Colombo MI, Coombs GH, Coppens I, Jayabalasingham B, Langsley G, de Castro SL, Menna-Barreto R, Mottram JC, Navarro M, Rigden DJ, Romano PS, Stoka V, Turk B, Michels PAM. Autophagy in protists. Autophagy 2011; 7:127-58. [PMID: 20962583 DOI: 10.4161/auto.7.2.13310] [Citation(s) in RCA: 133] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Autophagy is the degradative process by which eukaryotic cells digest their own components using acid hydrolases within the lysosome. Originally thought to function almost exclusively in providing starving cells with nutrients taken from their own cellular constituents, autophagy is in fact involved in numerous cellular events including differentiation, turnover of macromolecules and organelles, and defense against parasitic invaders. During the last 10-20 years, molecular components of the autophagic machinery have been discovered, revealing a complex interactome of proteins and lipids, which, in a concerted way, induce membrane formation to engulf cellular material and target it for lysosomal degradation. Here, our emphasis is autophagy in protists. We discuss experimental and genomic data indicating that the canonical autophagy machinery characterized in animals and fungi appeared prior to the radiation of major eukaryotic lineages. Moreover, we describe how comparative bioinformatics revealed that this canonical machinery has been subject to moderation, outright loss or elaboration on multiple occasions in protist lineages, most probably as a consequence of diverse lifestyle adaptations. We also review experimental studies illustrating how several pathogenic protists either utilize autophagy mechanisms or manipulate host-cell autophagy in order to establish or maintain infection within a host. The essentiality of autophagy for the pathogenicity of many parasites, and the unique features of some of the autophagy-related proteins involved, suggest possible new targets for drug discovery. Further studies of the molecular details of autophagy in protists will undoubtedly enhance our understanding of the diversity and complexity of this cellular phenomenon and the opportunities it offers as a drug target.
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Affiliation(s)
- Michael Duszenko
- Interfaculty Institute for Biochemistry, University of Tübingen, Tübingen, Germany
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16
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Sajid M, Robertson SA, Brinen LS, McKerrow JH. Cruzain : the path from target validation to the clinic. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 712:100-15. [PMID: 21660661 DOI: 10.1007/978-1-4419-8414-2_7] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cruzain is the major papain-like cysteine protease of Trypanosoma cruzi, the etiological agent causing Chagas' disease in humans in South America. Cruzain is indispensable for the survival and propagation of this protozoan parasite and therefore, it has attracted considerable interest as a potential drug target. This chapter charts the path from the initial identification of this proteases activity and its validation as a bone fide drug target to the arduous task of the discovery of an inhibitor targeting this protease and finally the path towards the clinic.
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Affiliation(s)
- Mohammed Sajid
- Afd. Parasitologie, Leiden University Medical Center, Leiden, The Netherlands
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17
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Bilgin M, Neuhof C, Doerr O, Benscheid U, Andrade SS, Most A, Abdallah Y, Parahuleva M, Guenduez D, Oliva ML, Erdogan A. Bauhinia bauhinioides cruzipain inhibitor reduces endothelial proliferation and induces an increase of the intracellular Ca2+ concentration. J Physiol Biochem 2010; 66:283-90. [DOI: 10.1007/s13105-010-0032-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2010] [Accepted: 06/30/2010] [Indexed: 10/19/2022]
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18
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Trossini GHG, Malvezzi A, T.-do Amaral A, Rangel-Yagui CO, Izidoro MA, Cezari MHS, Juliano L, Chin CM, Menezes CMS, Ferreira EI. Cruzain inhibition by hydroxymethylnitrofurazone and nitrofurazone: investigation of a new target in Trypanosoma cruzi. J Enzyme Inhib Med Chem 2009; 25:62-7. [DOI: 10.3109/14756360902941058] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
| | - Alberto Malvezzi
- Departamento de Química Fundamental, Instituto de Química, USP, São Paulo, Brazil
| | - Antonia T.-do Amaral
- Departamento de Química Fundamental, Instituto de Química, USP, São Paulo, Brazil
| | | | - Mario A. Izidoro
- Departamento de Biofísica, INFAR, Escola Paulista de Medicina, UNIFESP, São Paulo, Brazil
| | - Maria Helena S. Cezari
- Departamento de Biofísica, INFAR, Escola Paulista de Medicina, UNIFESP, São Paulo, Brazil
| | - Luiz Juliano
- Departamento de Biofísica, INFAR, Escola Paulista de Medicina, UNIFESP, São Paulo, Brazil
| | - Chung Man Chin
- Faculdade de Ciências Farmacêutica, UNESP, São Paulo, Brazil
| | - Carla M. S. Menezes
- Departamento de Farmácia, Faculdade de Ciências Farmacêuticas, USP, São Paulo, Brazil
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19
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Magdaleno A, Ahn IY, Paes LS, Silber AM. Actions of a proline analogue, L-thiazolidine-4-carboxylic acid (T4C), on Trypanosoma cruzi. PLoS One 2009; 4:e4534. [PMID: 19229347 PMCID: PMC2645137 DOI: 10.1371/journal.pone.0004534] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2008] [Accepted: 01/07/2009] [Indexed: 12/18/2022] Open
Abstract
It is well established that L-proline has several roles in the biology of trypanosomatids. In Trypanosoma cruzi, the etiological agent of Chagas' disease, this amino acid is involved in energy metabolism, differentiation processes and resistance to osmotic stress. In this study, we analyzed the effects of interfering with L-proline metabolism on the viability and on other aspects of the T. cruzi life cycle using the proline analogue L- thiazolidine-4-carboxylic acid (T4C). The growth of epimastigotes was evaluated using different concentrations of T4C in standard culture conditions and at high temperature or acidic pH. We also evaluated possible interactions of this analogue with stress conditions such as those produced by nutrient starvation and oxidative stress. T4C showed a dose-response effect on epimastigote growth (IC(50) = 0.89+/-0.02 mM at 28 degrees C), and the inhibitory effect of this analogue was synergistic (p<0.05) with temperature (0.54+/-0.01 mM at 37 degrees C). T4C significantly diminished parasite survival (p<0.05) in combination with nutrient starvation and oxidative stress conditions. Pre-incubation of the parasites with L-proline resulted in a protective effect against oxidative stress, but this was not seen in the presence of the drug. Finally, the trypomastigote bursting from infected mammalian cells was evaluated and found to be inhibited by up to 56% when cells were treated with non-toxic concentrations of T4C (between 1 and 10 mM). All these data together suggest that T4C could be an interesting therapeutic drug if combined with others that affect, for example, oxidative stress. The data also support the participation of proline metabolism in the resistance to oxidative stress.
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Affiliation(s)
- Anahí Magdaleno
- Departamento de Parasitología, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Il-Young Ahn
- Departamento de Parasitología, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Lisvane Silva Paes
- Departamento de Parasitología, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Ariel M. Silber
- Departamento de Parasitología, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
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20
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Rudenskaya GN, Pupov DV. Cysteine proteinases of microorganisms and viruses. BIOCHEMISTRY (MOSCOW) 2008; 73:1-13. [PMID: 18294123 PMCID: PMC7087786 DOI: 10.1134/s000629790801001x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This review considers properties of secreted cysteine proteinases of protozoa, bacteria, and viruses and presents information on the contemporary taxonomy of cysteine proteinases. Literature data on the structure and physicochemical and enzymatic properties of these enzymes are reviewed. High interest in cysteine proteinases is explained by the discovery of these enzymes mostly in pathogenic organisms. The role of the proteinases in pathogenesis of several severe diseases of human and animals is discussed.
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Affiliation(s)
- G N Rudenskaya
- Faculty of Chemistry, Lomonosov Moscow State University, Moscow, Russia.
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21
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Savel J, Durand R. Dihydrofolate reductase inhibitors: new developments in antiparasitic chemotherapy. Expert Opin Ther Pat 2005. [DOI: 10.1517/13543776.11.8.1285] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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22
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Gorr TA, Cahn JD, Yamagata H, Bunn HF. Hypoxia-induced Synthesis of Hemoglobin in the Crustacean Daphnia magna Is Hypoxia-inducible Factor-dependent. J Biol Chem 2004; 279:36038-47. [PMID: 15169764 DOI: 10.1074/jbc.m403981200] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Of the four known globin genes that exist in the fresh-water crustacean Daphnia magna, several are individually induced by hypoxia, lending pale normoxic animals a visible red color when challenged by oxygen deprivation. The promoter regions of the Daphnia globin genes each contain numerous hypoxia response elements (HREs) as potential binding sites for hypoxia-inducible factors (HIFs). Daphnia HIF, bound to human HRE sequences, was detected in extracts from hypoxic (red), but not normoxic (pale), animals. Taking advantage of the phylogenetically conserved HIF/HRE recognition, we employed heterologous transfections of HIF-expressing human and Drosophila cells to model HIF signaling in Daphnia. These experiments revealed that three functional HREs within the promoter of the D. magna globin-2 gene cooperate for maximal hypoxic induction of a downstream luciferase reporter gene. Two of these three cis-elements, at promoter positions -258 and -107, are able to specifically bind human, Drosophila, or Daphnia HIF complexes in vitro. The same two sites are also necessary for maximal induction of reporter transcription under low oxygen tension in the presence of either endogenous human or overexpressed Drosophila HIF proteins. The third motif of the globin-2 gene promoter, a CACGTG palindrome at position -146, functions as a docking site for an unknown constitutive transcription factor. In human cells, this -146 complex interferes with HIF occupancy at the adjacent -107 HRE and thus controls the extent of HIF-mediated hypoxic activation of the downstream target.
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Affiliation(s)
- Thomas A Gorr
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
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23
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Gorr TA, Tomita T, Wappner P, Bunn HF. Regulation of Drosophila hypoxia-inducible factor (HIF) activity in SL2 cells: identification of a hypoxia-induced variant isoform of the HIFalpha homolog gene similar. J Biol Chem 2004; 279:36048-58. [PMID: 15169765 DOI: 10.1074/jbc.m405077200] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Although hypoxia-inducible factor-alpha (HIFalpha) subunit-specific hydroxylation and proteolytic breakdown explain the binary switch between the presence (hypoxia) and absence (normoxia) of HIFs, little is known of the mechanisms that fine-tune HIF activity under constant, rather than changing, oxygen tensions. Here, we report that the Drosophila HIFalpha homolog, the basic helix-loop-helix/PAS protein Sima (Similar), in hypoxic cultures of SL2 cells is expressed in full-length (fl) and splice variant (sv) isoforms. The following evidence supports the role of flSima as functional HIFalpha and the role of SL2 HIF as a transcriptional activator or suppressor. The pO(2) dependence of Sima abundance matched that of HIF activity. HIF-dependent changes in candidate target gene expression were detected through variously effective stimuli: hypoxia (strong) > iron chelation, e.g. desferrioxamine (moderate) >> transition metals, e.g. cobalt approximately normoxia (ineffective). Sima overexpression augmented hypoxic induction or suppression of different targets. In addition to the full-length exon 1-12 transcript yielding the 1510-amino acid HIFalpha homolog, the sima gene also expressed, specifically under hypoxia, an exon 1-7/12 splice variant, which translated into a 426-amino acid Sima truncation termed svSima. svSima contains basic helix-loop-helix and PAS sequences identical to those of flSima, but, because of deletion of exons 8-11, lacks the oxygen-dependent degradation domain and nuclear localization signals. Overexpressed svSima failed to transactivate reporter genes. However, it attenuated HIF (Sima.Tango)-stimulated reporter expression in a dose-dependent manner. Thus, svSima has the potential to regulate Drosophila HIF function under steady and hypoxic pO(2) by creating a cytosolic sink for the Sima partner protein Tango.
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Affiliation(s)
- Thomas A Gorr
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
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24
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Dardenne LE, Werneck AS, de Oliveira Neto M, Bisch PM. Electrostatic properties in the catalytic site of papain: A possible regulatory mechanism for the reactivity of the ion pair. Proteins 2003; 52:236-53. [PMID: 12833547 DOI: 10.1002/prot.10368] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We present an analysis of the electrostatic properties in the catalytic site of papain (EC 3.4.22.2), an archetype enzyme of the C1 cysteine proteinase family, and we investigate their possible role in the formation, stabilization and regulation of the Cys25((-))...His159((+)) catalytic ion pair. The electrostatic properties were computed using a reassociation method based in multicentered multipolar expansions obtained from ab initio quantum calculations of overlapping protein fragments. Solvent effects were introduced by coupling the use of multicentered multipolar expansions to two continuum boundary element methods to solve the Poisson and the linearized Poisson-Boltzmann equations. The electrostatic profile found in the proton transfer region of papain showed that this enzyme has a well-defined electrostatic environment to favor the formation and stabilization of the catalytic ion pair. The papain catalytic site electrostatic profile can be considered as an electrostatic fingerprint of the papain family with the following characteristics: (i) the presence of a net electric field highly aligned in the (Cys25)-SG-->(His159)-ND1 direction; (ii) the electrostatic profile has a saddle-point character; (iii) it is basically a local environmental effect. Furthermore, our analysis describes a possible regulatory mechanism (the E(SG-->ND1) attenuation effect) controlling the ion pair reactivity and permits to infer the Asp57 acidic residue as the most probable candidate to act as the electrostatic modulator.
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Affiliation(s)
- Laurent E Dardenne
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro-UFRJ, CCS, Bloco G, Ilha do Fundão, 21949-900 Rio de Janeiro, RJ, Brazil
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25
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De Gaudenzi JG, D'Orso I, Frasch ACC. RNA recognition motif-type RNA-binding proteins in Trypanosoma cruzi form a family involved in the interaction with specific transcripts in vivo. J Biol Chem 2003; 278:18884-94. [PMID: 12637517 DOI: 10.1074/jbc.m301756200] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Trypanosomes, protozoan parasites from the order Kinetoplastida, have to deal with environmental changes during the interaction with their hosts. Trypanosoma cruzi, the causative agent of Chagas' disease, uses post-transcriptional mechanisms to regulate gene expression. However, few RNA-binding proteins involved in mRNA turnover control have been identified to date. In this work, an RNA recognition motif (RRM)-type RNA-binding protein family named T. cruzi RNA-binding protein (TcRBP) and composed of at least six members was identified. The genomic organization of four members revealed a head to tail arrangement within a region of 15 kilobase pairs. TcRBP members have a common RRM and different auxiliary domains with a high content of glycine, glutamine, and histidine residues within their N- and C-terminal regions. TcRBPs differ in their expression patterns as well as in their homoribopolymer binding interaction in vitro, although they preferentially recognize poly(U) and poly(G) RNAs. An interesting observation was the relaxed RNA-binding interactions with several trypanosome transcripts in vitro. In contrast, co-immunoprecipitation experiments of TcRBP-containing ribonucleoprotein complexes formed in vivo revealed a highly restricted binding interaction with specific RNAs. Several TcRBP-containing complexes are stage-specific and, in some cases, bear the poly(A)-binding protein TcPABP1. Altogether, these results suggest that TcRBPs might be modulated in vivo, to favor or preclude the interaction with specific transcripts in a developmentally regulated manner.
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Affiliation(s)
- Javier G De Gaudenzi
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús, CONICET-UNSAM, 1650 San Martín, Provincia de Buenos Aires, Argentina
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26
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Dickinson DP. Salivary (SD-type) cystatins: over one billion years in the making--but to what purpose? CRITICAL REVIEWS IN ORAL BIOLOGY AND MEDICINE : AN OFFICIAL PUBLICATION OF THE AMERICAN ASSOCIATION OF ORAL BIOLOGISTS 2003; 13:485-508. [PMID: 12499242 DOI: 10.1177/154411130201300606] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Human saliva contains relatively abundant proteins that are related ancestrally in sequence to the cystatin superfamily. Most, although not all, members of this superfamily are potent inhibitors of cysteine peptidases. Four related genes have been identified, CST1, 2, 4 and 5, encoding cystatins SN, SA, S, and D, respectively. CST1, 4, and probably CST5 are now known to be expressed in a limited number of other tissues in the body, primarily in exocrine epithelia, and the term SD-type cystatin is more appropriate than 'salivary cystatin'. These genes are co-ordinately regulated in the submandibular gland during post-natal development. The organization of these tissue-specifically-expressed genes in the genome, and their phylogeny, indicate that they evolved from an ancestral housekeeping gene encoding the ubiquitously expressed cystatin C, and are members of a larger protein family. Their relationship to rat cystatin S, a developmentally regulated rodent submandibular gland protein, remains to be established. In this review, the evolution of the SD-type cystatins in the cystatin superfamily, their genomics, expression, and structure-function relationships are examined and compared with known cystatin functions, with the goal of providing clues to their biological roles.
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Affiliation(s)
- D P Dickinson
- Medical College of Georgia, School of Dentistry, Department of Oral Biology and Maxillofacial Pathology, 1120 15th Street, Augusta, GA 30912, USA.
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27
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Lecaille F, Kaleta J, Brömme D. Human and parasitic papain-like cysteine proteases: their role in physiology and pathology and recent developments in inhibitor design. Chem Rev 2002; 102:4459-88. [PMID: 12475197 DOI: 10.1021/cr0101656] [Citation(s) in RCA: 395] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Fabien Lecaille
- Mount Sinai School of Medicine, Department of Human Genetics, Fifth Avenue at 100th Street, New York, New York 10029, USA
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28
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Abstract
Proteases from a variety of protozoan parasites have been characterized at the molecular and cellular levels, and the many roles that proteases play in these organisms are coming into focus. Central roles have been proposed for proteases in diverse processes such as host cell invasion and egress, encystation, excystation, catabolism of host proteins, differentiation, cell cycle progression, cytoadherence, and both stimulation and evasion of host immune responses. Detailed structural and functional characterization of parasite proteases has led to novel insights into the workings of these fascinating catalytic machines. The possibility of developing selective inhibitors of key proteases of pathogenic parasites into novel chemotherapeutic strategies is being vigorously explored.
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Affiliation(s)
- Michael Klemba
- Departments of Medicine and Molecular Microbiology, Howard Hughes Medical Institute, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, Missouri 63110, USA.
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29
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Rigden DJ, Mosolov VV, Galperin MY. Sequence conservation in the chagasin family suggests a common trend in cysteine proteinase binding by unrelated protein inhibitors. Protein Sci 2002; 11:1971-7. [PMID: 12142451 PMCID: PMC2373688 DOI: 10.1110/ps.0207202] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2002] [Revised: 05/13/2002] [Accepted: 05/21/2002] [Indexed: 10/27/2022]
Abstract
The recently described inhibitor of cysteine proteinases from Trypanosoma cruzi, chagasin, was found to have close homologs in several eukaryotes, bacteria and archaea, the first protein inhibitors of cysteine proteases in prokaryotes. These previously uncharacterized 110-130 residue-long proteins share a well-conserved sequence motif that corresponds to two adjacent beta-strands and the short loop connecting them. Chagasin-like proteins also have other conserved, mostly aromatic, residues, and share the same predicted secondary structure. These proteins adopt an all-beta fold with eight predicted beta-strands of the immunoglobulin type. The phylogenetic distribution of the chagasins generally correlates with the presence of papain-like cysteine proteases. Previous studies have uncovered similar trends in cysteine proteinase binding by two unrelated inhibitors, stefin and p41, that belong to the cystatin and thyroglobulin families, respectively. A hypothetical model of chagasin-cruzipain interaction suggests that chagasin may dock to the cruzipain active site in a similar manner with the conserved NPTTG motif of chagasin forming a loop that is similar to the wedge structures formed at the active sites of papain and cathepsin L by stefin and p41.
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Affiliation(s)
- Daniel J Rigden
- National Centre of Genetic Resources and Biotechnology, Cenargen/Embrapa, S.A.I.N. Parque Rural, Final W5 Norte, 70770-900 Brasília, Brazil.
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Lalmanach G, Boulangé A, Serveau C, Lecaille F, Scharfstein J, Gauthier F, Authié E. Congopain from Trypanosoma congolense: drug target and vaccine candidate. Biol Chem 2002; 383:739-49. [PMID: 12108538 DOI: 10.1515/bc.2002.077] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Trypanosomes are the etiological agents of human sleeping sickness and livestock trypanosomosis (nagana), which are major diseases in Africa. Their cysteine proteases (CPs), which are members of the papain family, are expressed during the infective stages of the parasites' life cycle. They are suspected to act as pathogenic factors in the mammalian host, where they also trigger prominent immune responses. Trypanosoma congolense, a major pathogenic species in livestock, possesses at least two families of closely related CPs, named CP1 and CP2. Congopain, a CP2-type of enzyme, shares structural and functional resemblances with cruzipain from T. cruzi and with mammalian cathepsin L. Like CPs from other Trypanosomatids, congopain might be an attractive target for trypanocidal drugs. Here we summarise the current knowledge in the two main areas of research on congopain: first, the biochemical properties of congopain were characterised and its substrate specificity was determined, as a first step towards drug design; second, the possibility was being explored that inhibition of congopain by host-specific antibodies may mitigate the pathology associated with trypanosome infection.
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Affiliation(s)
- Gilles Lalmanach
- Laboratoire d'Enzymologie et Chimie des Protéines, INSERM EMI-U 00.10, Université François Rabelais, Faculté de Médecine, Tours, France
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31
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Giordanengo L, Guiñazú N, Stempin C, Fretes R, Cerbán F, Gea S. Cruzipain, a major Trypanosoma cruzi antigen, conditions the host immune response in favor of parasite. Eur J Immunol 2002; 32:1003-11. [PMID: 11920566 DOI: 10.1002/1521-4141(200204)32:4<1003::aid-immu1003>3.0.co;2-p] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We recently demonstrated that humoral immune response to cruzipain, a major antigen of Trypanosoma cruzi parasite, is implicated in the pathogenesis of experimental Chagas' disease. In the present study, the spleen cell phenotype and the cytokine profile induced by cruzipain in immunized mice were analyzed. The results showed that cruzipain increases the number of spleen cells with large size and granularity. Splenocyte populations with CD19(+), Mac-1(+), Gr-1(+) and CD11c(+) positive surface markers significantly increased in immune mice compared to controls ones. Histological study revealed the presence of high number of megacariocyte and granulocyte-macrophage progenitors, indicating extramedullary hemopoiesis in spleens of immune mice. The finding of high levels of IL-4, IL5 and IL-10 and low levels of IFN-gamma and IL-12 in supernatants of immune cells stimulated with cruzipain indicates a preferential activation of T2 type cells in immune animals. To investigate the role of innate immunity cells, the classical and alternative metabolic pathways of spleen macrophages from immune mice stimulated by cruzipain were also studied. The results showed an increase of urea associated with a decrease of nitrite levels, suggesting that cruzipain up-regulates the arginase way. Therefore, cruzipain leads to T2 type cytokine profile which may enhance the arginase via in the macrophages promoting a susceptible mechanism to infection. Thus, we postulate that during T. cruzi infection, cruzipain could be used by the parasite to spread inside the host.
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Affiliation(s)
- Laura Giordanengo
- Inmunología, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
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Duschak VG, Riarte A, Segura EL, Laucella SA. Humoral immune response to cruzipain and cardiac dysfunction in chronic Chagas disease. Immunol Lett 2001; 78:135-42. [PMID: 11578687 DOI: 10.1016/s0165-2478(01)00255-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The humoral immune response to epitopes expressed on cruzipain was evaluated in 31 Chagas disease patients (CDP) with different degrees of cardiac dysfunction. We took advantage of the availability of anti-Trypanosoma cruzi microsomal fraction monoclonal antibodies (MoAbs) reactive with epitopes that are recognized (5A9B11) or not recognized (1A10C11) by CDP sera. The 5A9B11- and 1A10C11-like epitopes are expressed on cruzipain. The reactivity of 5A9B11 against cruzipain was completely inhibited by sera of severe cardiopathy patients while a partial inhibition was found with sera from chagasic patients with mild disease. CDP sera did not block cruzipain recognition by 1A10C11. The antigenic determinants recognized by CDP sera appeared to be linear and carbohydrate free. When the overall anti-cruzipain immune response was evaluated, 70% of CDP with severe disease showed cruzipain titers higher than 1/800 while none of them displayed titers lower that 1/400. This report shows for the first time that the humoral immune response against epitopes expressed on cruzipain appeared to be related with the severity of chronic Chagas disease.
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Affiliation(s)
- V G Duschak
- Instituto de Investigaciones Biotecnólogicas, Universidad Nacional de General San Martín, INTI. Av. Gral. Paz entre Albarellos y Constituyentes (Edificio 24) Casilla de Correo 30 (1650), San Martín, Buenos Aires, Argentina
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Duschak VG, Ciaccio M, Nassert JR, Basombrio MA. Enzymatic activity, protein expression, and gene sequence of cruzipain in virulent and attenuated Trypanosoma cruzi strains. J Parasitol 2001; 87:1016-22. [PMID: 11695358 DOI: 10.1645/0022-3395(2001)087[1016:eapeag]2.0.co;2] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Protein expression, characterized in Western blots and gelatinolytic activity, of cruzipain (Cr), the major Trypanosoma cruzi cysteine proteinase, was compared among 3 attenuated T. cruzi strains (TUL 0, TCC, and Y null) and their virulent counterparts (TUL 2, Tulahuen, and Y). All attenuated strains displayed a weaker gelatinolytic activity as compared with their virulent counterparts. The electrophoretic mobility and immunological reactivity revealed quantitative and qualitative differences, with the attenuated parasites showing bands of less density in all strains and lower mobility in 2 of them, as compared with the virulent strains. Sequence analysis of 1 Cr gene in the Tulahuen and TCC strains indicated 37/1404 base pair substitutions, corresponding to 20 amino acid changes in the attenuated strain. A similar comparative analysis of 1 Cr gene between Y and Y null strains showed 13/1404 base pair substitutions, corresponding to 8 amino acid changes in the attenuated strain. Although enough variability exists in the Cr gene to allow for less- or nonfunctional isoforms of the protein, further clones should be analyzed to establish whether attenuation is regularly associated with specific sequence changes of this enzyme.
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Affiliation(s)
- V G Duschak
- Instituto de Investigaciones Biotecnológicas, Universidad de San Martin, INTI, Provincia de Buenos Aires, Argentina
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Bhattacharya S, Ghosh S, Chakraborty S, Bera AK, Mukhopadhayay BP, Dey I, Banerjee A. Insight to structural subsite recognition in plant thiol protease-inhibitor complexes : understanding the basis of differential inhibition and the role of water. BMC STRUCTURAL BIOLOGY 2001; 1:4. [PMID: 11602025 PMCID: PMC57815 DOI: 10.1186/1472-6807-1-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2001] [Accepted: 09/11/2001] [Indexed: 12/03/2022]
Abstract
BACKGROUND This work represents an extensive MD simulation / water-dynamics studies on a series of complexes of inhibitors (leupeptin, E-64, E-64-C, ZPACK) and plant cysteine proteases (actinidin, caricain, chymopapain, calotropin DI) of papain family to understand the various interactions, water binding mode, factors influencing it and the structural basis of differential inhibition. RESULTS The tertiary structure of the enzyme-inhibitor complexes were built by visual interactive modeling and energy minimization followed by dynamic simulation of 120 ps in water environment. DASA study with and without the inhibitor revealed the potential subsite residues involved in inhibition. Though the interaction involving main chain atoms are similar, critical inspection of the complexes reveal significant differences in the side chain interactions in S2-P2 and S3-P3 pairs due to sequence differences in the equivalent positions of respective subsites leading to differential inhibition. CONCLUSION The key finding of the study is a conserved site of a water molecule near oxyanion hole of the enzyme active site, which is found in all the modeled complexes and in most crystal structures of papain family either native or complexed. Conserved water molecules at the ligand binding sites of these homologous proteins suggest the structural importance of the water, which changes the conventional definition of chemical geometry of inhibitor binding domain, its shape and complimentarity. The water mediated recognition of inhibitor to enzyme subsites (Pn.H2O.Sn) of leupeptin acetyl oxygen to caricain, chymopapain and calotropinDI is an additional information and offer valuable insight to potent inhibitor design.
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Affiliation(s)
- Suparna Bhattacharya
- Biophysics Division, Bose Institute, P 1/12, C.I.T. Scheme VIIM, Calcutta, 700054, India
| | - Sreya Ghosh
- Biophysics Division, Bose Institute, P 1/12, C.I.T. Scheme VIIM, Calcutta, 700054, India
| | - Sibani Chakraborty
- Biophysics Division, Bose Institute, P 1/12, C.I.T. Scheme VIIM, Calcutta, 700054, India
| | - Asim K Bera
- Biophysics Division, Bose Institute, P 1/12, C.I.T. Scheme VIIM, Calcutta, 700054, India
| | - Bishnu P Mukhopadhayay
- Biophysics Division, Bose Institute, P 1/12, C.I.T. Scheme VIIM, Calcutta, 700054, India
| | - Indrani Dey
- Biophysics Division, Bose Institute, P 1/12, C.I.T. Scheme VIIM, Calcutta, 700054, India
| | - Asok Banerjee
- Biophysics Division, Bose Institute, P 1/12, C.I.T. Scheme VIIM, Calcutta, 700054, India
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Magdesian MH, Giordano R, Ulrich H, Juliano MA, Juliano L, Schumacher RI, Colli W, Alves MJ. Infection by Trypanosoma cruzi. Identification of a parasite ligand and its host cell receptor. J Biol Chem 2001; 276:19382-9. [PMID: 11278913 DOI: 10.1074/jbc.m011474200] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The infective trypomastigote stage of Trypanosoma cruzi expresses a set of surface glycoproteins that are known collectively as Tc85 and belong to the gp85/trans-sialidase supergene family. A member of this family, Tc85-11, with adhesive properties to laminin and cell surfaces was recently cloned. In this report, the Tc85-11 domain for cell binding and its corresponding receptor on epithelial cell LLC-MK(2) are described. Using synthetic peptides corresponding to the Tc85-11 carboxyl-terminal segment, we show that the mammalian cell-binding domain colocalizes to the most conserved motif of the trypanosome gp85/trans-sialidase supergene family (VTVXNVFLYNR). Even though Tc85-11 binds to laminin, the 19-residue cell-binding peptide (peptide J) does not contain the laminin-binding site, because it does not bind to laminin or inhibit cell binding to this glycoprotein. The host cell receptor for the peptide was characterized as cytokeratin 18. Addition of anti-cytokeratin antibodies to the culture medium significantly inhibited the infection of epithelial cells by T. cruzi. Tc85-11 is a multiadhesive glycoprotein, encoding at least two different binding sites, one for laminin and one for cytokeratin 18, that allow the parasite to overcome the barriers imposed by cell membranes, extracellular matrices, and basal laminae to reach the definitive host cell. This is the first description of a direct interaction between cytokeratin and a protozoan parasite.
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Affiliation(s)
- M H Magdesian
- Departamento de Bioquimica, Instituto de Quimica, Universidade de São Paulo, Caixa Postal 26077, São Paulo 05513-970, São Paulo, Brazil
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Giordanengo L, Maldonado C, Rivarola HW, Iosa D, Girones N, Fresno M, Gea S. Induction of antibodies reactive to cardiac myosin and development of heart alterations in cruzipain-immunized mice and their offspring. Eur J Immunol 2000; 30:3181-9. [PMID: 11093133 DOI: 10.1002/1521-4141(200011)30:11<3181::aid-immu3181>3.0.co;2-a] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Human and murine infection with Trypanosoma cruzi parasite is usually accompanied by strong humoral and cellular immune response to cruzipain, a parasite immunodominant antigen. In the present study we report that the immunization of mice with cruzipain devoid of enzymatic activity, was able to induce antibodies which bind to a 223-kDa antigen from a mouse heart extract. We identified this protein as the mouse cardiac myosin heavy chain by sequencing analysis. The study of IgG isotype profile revealed the occurrence of all IgG isotypes against cruzipain and myosin. IgG1 showed the strongest reactivity against cruzipain, whereas IgG2a was the main isotype against myosin. Anti-cruzipain antibodies purified by immunoabsorption recognized the cardiac myosin heavy chain, suggesting cross-reactive epitopes between cruzipain and myosin. Autoimmune response in mice immunized with cruzipain was associated to heart conduction disturbances. In addition, ultrastructural findings revealed severe alterations of cardiomyocytes and IgG deposit on heart tissue of immunized mice. We investigated whether antibodies induced by cruzipain transferred from immunized mothers to their offsprings could alter the heart function in the pups. All IgG isotypes against cruzipain derived from transplacental crossing were detected in pups' sera. Electrocardiographic studies performed in the offsprings born to immunized mothers revealed conduction abnormalities. These results provide strong evidence for a pathogenic role of autoimmune response induced by a purified T. cruzi antigen in the development of experimental Chagas' disease.
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Affiliation(s)
- L Giordanengo
- Inmunología, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
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37
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Venturini G, Salvati L, Muolo M, Colasanti M, Gradoni L, Ascenzi P. Nitric oxide inhibits cruzipain, the major papain-like cysteine proteinase from Trypanosoma cruzi. Biochem Biophys Res Commun 2000; 270:437-41. [PMID: 10753643 DOI: 10.1006/bbrc.2000.2447] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nitric oxide (NO) is a pluripotent regulatory molecule showing, among others, an antiparasitic activity. Moreover, NO inhibits cysteine proteinase action by nitrosylating the Cys catalytic residue. In the present study, the inhibitory effect of the substrate N-alpha-benzyloxycarbonyl-L-phenylalanyl-L-arginine-(7-amino-4-methyl coumarin) and of NO on the catalytic activity of cruzipain, the major papain-like cysteine proteinase from Trypanosoma cruzi (the hemoflagellate protozoan parasite which causes the American trypanosomiasis), is reported. In particular, NO-donors S-nitroso-glutathione (GSNO), (+/-)-(E)-4-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide (NOR-3), 3-morpholinosydnonimine (SIN-1), S-nitroso-acetyl-penicillamine (SNAP), and sodium nitroprusside (SNP) dose-dependently inhibited cruzipain, this effect being likely attributable to the S-nitrosylation of the Cys25 catalytic residue. These results were analyzed in parallel with those concerning the inhibitory effect of the substrate and of NO on the catalytic activity of falcipain, the cruzipain-homologous cysteine proteinase from Plasmodium falciparum. The modulation of the cruzipain and falcipain activity by NO may be relevant in developing new strategies against T. cruzi and P. falciparum in human host. As a whole, the NO-mediated S-nitrosylation of pathogenic viral, bacterial, fungal, and parasitic cysteine proteinases may represent a general mechanism of antimicrobial and antiparasitic host defences.
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Affiliation(s)
- G Venturini
- Dipartimento di Biologia, Università 'Roma Tre', Viale Guglielmo Marconi 446, Rome, I-00146, Italy
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Stoka V, Turk B, McKerrow JH, Björk I, Cazzulo JJ, Turk V. The high stability of cruzipain against pH-induced inactivation is not dependent on its C-terminal domain. FEBS Lett 2000; 469:29-32. [PMID: 10708750 DOI: 10.1016/s0014-5793(00)01221-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Unlike mammalian lysosomal cysteine proteases, the trypanosomal cysteine protease cruzipain contains a 130-amino acid residue C-terminal domain, in addition to the catalytic domain, and it is stable at neutral pH. The endogenous (with C-terminal domain) and recombinant (without C-terminal domain) cruzipains exhibit similar stabilities at both acid (k(inac)=3.1x10(-3) s(-1) and 4.4x10(-3) s(-1) at pH 2.75 for endogenous and recombinant cruzipain, respectively) and alkaline pH (k(inac)=3.0x10(-3) s(-1) and 3. 7x10(-3) s(-1) at pH 9.15 for endogenous and recombinant cruzipain, respectively). The pH-induced inactivation, which is a highly pH dependent first order process, is irreversible and accompanied by significant changes of secondary and tertiary structure as revealed by circular dichroism measurements. The different stability of cruzipain as compared to related proteases, is therefore due mainly to the different number, nature and distribution of charged residues within the catalytic domain and not due to addition of the C-terminal domain.
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Affiliation(s)
- V Stoka
- Department of Biochemistry and Molecular Biology, J. Stefan Institute, Jamova 39, Sl-1000, Ljubljana, Slovenia
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Labriola C, Cazzulo JJ, Parodi AJ. Trypanosoma cruzi calreticulin is a lectin that binds monoglucosylated oligosaccharides but not protein moieties of glycoproteins. Mol Biol Cell 1999; 10:1381-94. [PMID: 10233151 PMCID: PMC25283 DOI: 10.1091/mbc.10.5.1381] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Trypanosoma cruzi is a protozoan parasite that belongs to an early branch in evolution. Although it lacks several features of the pathway of protein N-glycosylation and oligosaccharide processing present in the endoplasmic reticulum of higher eukaryotes, it displays UDP-Glc:glycoprotein glucosyltransferase and glucosidase II activities. It is herewith reported that this protozoan also expresses a calreticulin-like molecule, the third component of the quality control of glycoprotein folding. No calnexin-encoding gene was detected. Recombinant T. cruzi calreticulin specifically recognized free monoglucosylated high-mannose-type oligosaccharides. Addition of anti-calreticulin serum to extracts obtained from cells pulse-chased with [35S]Met plus [35S]Cys immunoprecipitated two proteins that were identified as calreticulin and the lysosomal proteinase cruzipain (a major soluble glycoprotein). The latter but not the former protein disappeared from immunoprecipitates upon chasing cells. Contrary to what happens in mammalian cells, addition of the glucosidase II inhibitor 1-deoxynojirimycin promoted calreticulin-cruzipain interaction. This result is consistent with the known pathway of protein N-glycosylation and oligosaccharide processing occurring in T. cruzi. A treatment of the calreticulin-cruzipain complexes with endo-beta-N-acetylglucosaminidase H either before or after addition of anti-calreticulin serum completely disrupted calreticulin-cruzipain interaction. In addition, mature monoglucosylated but not unglucosylated cruzipain isolated from lysosomes was found to interact with recombinant calreticulin. It was concluded that the quality control of glycoprotein folding appeared early in evolution, and that T. cruzi calreticulin binds monoglucosylated oligosaccharides but not the protein moiety of cruzipain. Furthermore, evidence is presented indicating that glucosyltransferase glucosylated cruzipain at its last folding stages.
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Affiliation(s)
- C Labriola
- Instituto de Investigaciones Bioquímicas Fundación Campomar, 1405 Buenos Aires, Argentina
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40
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Stoka V, Lenarcic B, Cazzulo JJ, Turk V. Cathepsin S and cruzipain are inhibited by equistatin from Actinia equina. Biol Chem 1999; 380:589-92. [PMID: 10384966 DOI: 10.1515/bc.1999.075] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Cathepsin S has been isolated for the first time from human tissue. It has a molecular mass of 24 kDa and an isoelectric point in the range of 8.2 to 8.6. The enzyme is inhibited by equistatin, which belongs to the thyropins, a new family of protein inhibitors, with an inhibition constant of Ki = 0.40 +/- 0.07 nM. Cruzipain, a cathepsin L-like enzyme sharing a 130 amino acid long C-terminal extension, is also strongly inhibited by equistatin (Ki = 0.028 +/- 0.006 nM). Together with previously reported data, these results further indicate that a functional heterogeneity exists among thyropin inhibitors, as demonstrated by their interaction with cathepsin S and cruzipain.
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Affiliation(s)
- V Stoka
- Department of Biochemistry and Molecular Biology, J. Stefan Institute, Ljubljana, Slovenia
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41
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Giordano R, Fouts DL, Tewari D, Colli W, Manning JE, Alves MJ. Cloning of a surface membrane glycoprotein specific for the infective form of Trypanosoma cruzi having adhesive properties to laminin. J Biol Chem 1999; 274:3461-8. [PMID: 9920891 DOI: 10.1074/jbc.274.6.3461] [Citation(s) in RCA: 95] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Trypomastigotes of Trypanosoma cruzi express a set of surface glycoproteins known, collectively, as Tc-85. A monoclonal antibody to these proteins, named H1A10, inhibits (50-90%) in vitro parasite interiorization into host cells, thus implicating these glycoproteins in the infection process. Two DNA inserts, a genomic DNA fragment and a full-length cDNA encoding the H1A10 epitope, have now been cloned and characterized. Results show that both have high sequence identity with all reported members of the gp85/trans-sialidase gene family, although the H1A10 epitope exists only in the Tc-85 subset of the family. The epitope has been mapped by competition of antibody binding to a Tc-85 recombinant protein with peptides having sequences predicted by the Tc-85 DNA sequence, which contains also putative N-glycosylation sites and COOH-terminal glycosylphosphatidylinositol anchor insertion sites, as expected, since an N-glycan chain and a glycosylphosphatidylinositol anchor have been characterized previously in the Tc-85 subset. The protein encoded by the full-length cDNA insert binds to cells and in vitro to laminin, but not to gelatin or fibronectin, in a saturable manner. For the first time it was possible to assign a defined ligand to a sequenced glycoprotein belonging to the gp85 family. This fact, together with the reported binding of family members to cell surfaces, reinforces the hypothesis that this family encodes glycoproteins with similar sequences but differing enough as to bind to different ligands and thus forming a family of adhesion glycoproteins enabling the parasite to overcome the barriers interposed by cell membranes, extracellular matrices, and basal laminae.
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Affiliation(s)
- R Giordano
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, Caixa Postal 26077, São Paulo 05599-970, S. P., Brazil
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Guerrero SA, Flohé L, Kalisz HM, Montemartini M, Nogoceke E, Hecht HJ, Steinert P, Singh M. Sequence, heterologous expression and functional characterization of tryparedoxin1 from Crithidia fasciculata. EUROPEAN JOURNAL OF BIOCHEMISTRY 1999; 259:789-94. [PMID: 10092865 DOI: 10.1046/j.1432-1327.1999.00087.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Tryparedoxin (TXN) has recently been discovered as a constituent of the complex peroxidase system in the trypanosomatid Crithidia fasciculata [Nogoceke et al. (1997) Biol. Chem. 378, 827-836] where it catalyzes the reduction of a peroxiredoxin-type peroxidase by trypanothione. Here we report on the full-length DNA sequence of the TXN previously isolated from C. fasciculata (TXN1). The deduced amino acid sequence comprises 147 residues and matches with all the peptide sequences of fragments obtained from TXN1. It shares a characteristic sequence motif YFSAxWCPPCR with some thioredoxin-related proteins of unknown function. This motif is homologous with the CXXC motif, which characterizes the thioredoxin superfamily of proteins and is known to catalyze disulfide reductions. Sequence conservations between TXNs and the typical thioredoxins are restricted to the intimate environment of the CXXC motif and three more remote residues presumed to contribute to the folding pattern of the thioredoxin-type proteins. The TXNs thus form a distinct molecular clade within the thioredoxin superfamily. TXN1 was expressed in Escherichia coli BL21 (DE3)pLysS as a C-terminally extended and His-tagged protein, isolated by chelate chromatography and characterized functionally. The recombinant product exhibited a kinetic pattern identical with, and kinetic parameters similar to those of the authentic enzyme in the trypanothione/peroxiredoxin oxidoreductase assay. The recombinant TXN1 can therefore be considered a valuable tool for the screening of specific inhibitors as potential trypanocidal agents.
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Affiliation(s)
- S A Guerrero
- Department of Biochemistry, Technical University of Braunschweig, Germany
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Engel JC, Doyle PS, Hsieh I, McKerrow JH. Cysteine protease inhibitors cure an experimental Trypanosoma cruzi infection. J Exp Med 1998; 188:725-34. [PMID: 9705954 PMCID: PMC2213346 DOI: 10.1084/jem.188.4.725] [Citation(s) in RCA: 306] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/1998] [Indexed: 11/24/2022] Open
Abstract
Trypanosoma cruzi is the causative agent of Chagas' disease. The major protease, cruzain, is a target for the development of new chemotherapy. We report the first successful treatment of an animal model of Chagas' disease with inhibitors designed to inactivate cruzain. Treatment with fluoromethyl ketone-derivatized pseudopeptides rescued mice from lethal infection. The optimal pseudopeptide scaffold was phenylalanine-homophenylalanine. To achieve cure of infection, this pseudopeptide scaffold was incorporated in a less toxic vinyl sulfone derivative. N-methyl piperazine-Phe-homoPhe-vinyl sulfone phenyl also rescued mice from a lethal infection. Six of the treated mice survived over nine months, three without further treatment. Three mice that had entered the chronic stage of infection were retreated with a 20-d regimen. At the conclusion of the experiments, five of the six mice had repeated negative hemacultures, indicative of parasitological cure. Studies of the effect of inhibitors on the intracellular amastigote form suggest that the life cycle is interrupted because of inhibitor arrest of normal autoproteolytic cruzain processing at the level of the Golgi complex. Parasites recovered from the hearts of treated mice showed the same abnormalities as those treated in vitro. No abnormalities were noted in the Golgi complex of host cells. This study provides proof of concept that cysteine protease inhibitors can be given at therapeutic doses to animals to selectively arrest a parasitic infection.
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Affiliation(s)
- J C Engel
- Department of Pathology, University of California San Francisco, California 94143, USA.
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Montemartini M, Kalisz HM, Kiess M, Nogoceke E, Singh M, Steinert P, Flohé L. Sequence, heterologous expression and functional characterization of a novel tryparedoxin from Crithidia fasciculata. Biol Chem 1998; 379:1137-42. [PMID: 9792447 DOI: 10.1515/bchm.1998.379.8-9.1137] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Tryparedoxin has recently been discovered as a constituent of the trypanosomal peroxidase system catalysing the reduction of a peroxiredoxin-type peroxidase by trypanothione [Nogoceke et al. (1997) Biol. Chem. 378, 827-836] and has attracted interest as a potential molecular target for the development of trypanocidal agents. Here we describe the first isolation of a novel gene from Crithidia fasciculata encoding a different tryparedoxin designated tryparedoxin II. The deduced amino acid sequence of tryparedoxin II (accession number AF055986) differs substantially from the partial sequence reported for the tryparedoxin described previously and now renamed tryparedoxin I. It shares the sequence motif Vx3FSAxWCPPCR shown to represent the catalytic site in tryparedoxin I [Gommel et al. (1997) Eur. J. Biochem. 248, 913-918] with mouse nucleoredoxin (accession number X92750), and a thioredoxin-like gene product of Caenorhabditis elegans (accession number U23511). Depending on which ATG is considered functional as translation start codon, tryparedoxin II, with 150 or 165 amino acid residues, is 50% larger than the typical thioredoxins. The tryparedoxins appear phylogenetically related to the thioredoxins, but sequence similarities are restricted to the active site motifs and their intimate neighbourhood. His-tagged tryparedoxin II expressed in E. coli exhibited ping-pong kinetics in the trypanothione:peroxiredoxin assay with kinetic parameters (KM peroxiredoxin = 4.2 microM, KM trypanothione = 33 microM, Vmax/[E] = 952 min(-1)) similar to those reported for tryparedoxin I [Gommel et al. (1997) Eur. J. Biochem. 248, 913-918]. The co-existence of two distinct tryparedoxins in C. fasciculata suggests diversified biological roles of this novel type of protein, which in trypanosomatids may substitute for the pleiotropic redox catalyst thioredoxin.
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Affiliation(s)
- M Montemartini
- Department of Biochemistry, Technical University of Braunschweig, Germany
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Montemartini M, Nogoceke E, Singh M, Steinert P, Flohé L, Kalisz HM. Sequence analysis of the tryparedoxin peroxidase gene from Crithidia fasciculata and its functional expression in Escherichia coli. J Biol Chem 1998; 273:4864-71. [PMID: 9478927 DOI: 10.1074/jbc.273.9.4864] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Tryparedoxin peroxidase from Crithidia fasciculata is an essential component of the trypanothione-dependent hydroperoxide metabolism in the trypanosomatids (Nogoceke, E., Gommel, D. U., Kiebeta, M., Kalisz, H. M., and Flohé, L. (1997) Biol. Chem. 378, 827-836). The tryparedoxin peroxidase gene and its flanking regions have been isolated and sequenced from a C. fasciculata genomic DNA library. It consists of an open reading frame of 564 base pairs encoding a protein of 188 amino acid residues. The gene, modified to encode 6 additional histidine residues, was expressed in Escherichia coli and the recombinant protein was purified to homogeneity by metal chelating chromatography. Recombinant tryparedoxin peroxidase has a subunit molecular mass of 21884 +/- 22 and contains two isoforms of pI 6.2 and 6.3. It exhibits a kinetic pattern identical to that of the authentic tryparedoxin peroxidase and has a similar specific activity of 2.51 units mg-1. The enzyme unequivocally belongs to the peroxiredoxin family of proteins, whose members have been found in all phyla. A phylogenetic tree comprising 47 protein and DNA sequences showed tryparedoxin peroxidase and a homologous Trypanosoma brucei sequence to form a distinct molecular clade. The consensus sequence: xnAx5-6Fx9Gx3Vx2Fx1Px2Fx1FVCPTEx21Sx1Dx7Wx16-19Dx15- 16Gx3Rx2Fx2Dx27Ax 1Qx4-11Cx1-3Wxn was demonstrated by alignment of the sequences of tryparedoxin peroxidase and 8 other peroxiredoxins with established peroxidase function.
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Affiliation(s)
- M Montemartini
- Gesellschaft für Biotechnologische Forschung (GBF) mbH, Mascheroder Weg 1, D-38124 Braunschweig, Germany
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Wiser MF, Lonsdale-Eccles JD, D'Alessandro A, Grab DJ. A cryptic protease activity from Trypanosoma cruzi revealed by preincubation with kininogen at low temperatures. Biochem Biophys Res Commun 1997; 240:540-4. [PMID: 9398600 DOI: 10.1006/bbrc.1997.7690] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Cysteine proteases have been identified in parasitic protozoa including the causative agent of Chagas' disease Trypanosoma cruzi. T. cruzi lysates subjected to substrate-containing SDS-polyacrylamide gel electrophoresis exhibit major bands of proteolytic activity in the 45-55 kDa molecular mass range (cruzipain activity). Paradoxically, addition of kininogen (a cystatin-like protease inhibitor) to the lysates before electrophoresis results in the appearance of additional bands of proteolytic activity in the 160-190 kDa molecular mass range. This inhibitor-activated protease activity depends upon the reaction conditions and exhibits novel properties. For example, a 24-48 hour preincubation at low temperature (-20 degrees C optimum) greatly enhances the proteolytic activity. The results suggest that a metastable complex forms between kininogen and a cryptic 30 kDa cysteine protease from T. cruzi and that this complex participates in the activation of proteolytic activity.
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Affiliation(s)
- M F Wiser
- Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana 70112, USA.
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Nogoceke E, Gommel DU, Kiess M, Kalisz HM, Flohé L. A unique cascade of oxidoreductases catalyses trypanothione-mediated peroxide metabolism in Crithidia fasciculata. Biol Chem 1997; 378:827-36. [PMID: 9377478 DOI: 10.1515/bchm.1997.378.8.827] [Citation(s) in RCA: 220] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Parasitic trypanosomatids comprise causative agents of debilitating or life-threatening tropical diseases. The limited capacity of these parasites to cope with oxidative stress has been discussed as a target area for therapeutic approaches but success has been hampered by a lack of comprehension of their peculiar oxidant defense system depending on the unique redox metabolite trypanothione. Here we report that trypanothione-dependent hydroperoxide metabolism in Crithidia fasciculata is catalysed by two distinct proteins working in concert. One is Cf16, a unique protein which, apart from a WCPPC sequence that resembles the thioredoxin-type WCG(A)PC motif, only shows low similarity to thioredoxin-like proteins of bacteria and invertebrates. The second component is Cf21, which can be classified as a member of the peroxiredoxin family of proteins. The two proteins have been purified to homogeneity and shown to be essential for the trypanothione-dependent removal of hydroperoxides. By means of selective derivatisation of the substrate-reduced proteins the flux of reduction equivalents from trypanothione to Cf16, Cf21 and finally to the hydroperoxide was elucidated. Cf21 proved to be a moderately efficient peroxidase with broad specificity. The rate constants for the reaction of the reduced protein with H2O2, t-butyl hydroperoxide, linoleic acid hydroperoxide and phosphatidylcholine hydroperoxide were 1.0 x 10(5), 1.2 x 10(5), 1.0 x 10(5) and 0.4 x 10(5) M-1S-1, respectively. The apparent rate constant for the regeneration of reduced Cf21 by Cf16 was in the range of 1.5-3.5 x 10(6) M-1S-1. This newly discovered metabolic pathway adds two further candidates to the list of potential targets for trypanocidal drugs.
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Affiliation(s)
- E Nogoceke
- GBF-Gesellschaft für Biotechnologische Forschung, Braunschweig, Germany
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