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Ilboudo K, Boulangé A, Hounyèmè RE, Gimonneau G, Kaboré J, Belem AGM, Desquesnes M, Lejon V, Koffi M, Jamonneau V, Thévenon S. Performance of diagnostic tests for Trypanosoma brucei brucei in experimentally infected pigs. PLoS Negl Trop Dis 2023; 17:e0011730. [PMID: 37943881 PMCID: PMC10662723 DOI: 10.1371/journal.pntd.0011730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 11/21/2023] [Accepted: 10/16/2023] [Indexed: 11/12/2023] Open
Abstract
Animal African trypanosomosis is an important vector-borne disease of livestock in sub-Saharan Africa. Pigs seem relatively tolerant to trypanosome infection and could act as a reservoir of trypanosomes affecting animals and humans. Our ability to reliably detect trypanosome infection in pigs depends on the performance of diagnostic tools, which is not well known. In pigs experimentally infected with Trypanosoma brucei brucei, we evaluated the performance of parasitological Buffy Coat Technique (BCT), two molecular (TBR and 5.8S PCR) and four serological tests (CATT, HAT Sero-K-Set rapid diagnostic test-RDT, indirect ELISA, immune trypanolysis). Most diagnostic tests showed high specificity, estimated at 100% (95% CI = 74-100%) with the exception of CATT and RDT whose specificity varied between 100% (95% CI = 74-100%) to 50% (95% CI = 7-93%) during the experiment. The sensitivity of each test fluctuated over the course of the infection. The percentage of positive BCT over the infection (30%) was lower than of positive PCR (56% and 62%, depending on primers). Among the serological tests, the percentage of positive tests was 97%, 96%, 86% and 84% for RDT, ELISA, immune trypanolysis and CATT, respectively. Fair agreement was observed between both molecular tests (κ = 0.36). Among the serological tests, the agreement between the ELISA and the RDT was substantial (κ = 0.65). Our results on the T.b. brucei infection model suggest that serological techniques are efficient in detecting the chronic phase of infection, PCR is able to detect positive samples several months after parasites inoculation while BCT becomes negative. BCT examination and RDT are useful to get a quick information in the field, and BCT can be used for treatment decision. ELISA appears most suited for epidemiological studies. The selection of diagnostic tests for trypanosomosis in pigs depends on the context, the objectives and the available resources.
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Affiliation(s)
- Kadidiata Ilboudo
- Unité de Recherche sur les Maladies à Vecteurs et Biodiversité, Centre International de Recherche-Développement sur l’Elevage en zone Subhumide, Bobo-Dioulasso, Burkina Faso
- Unité de Formation et de Recherche en Sciences de la Vie et de la Terre, Université Nazi Boni, Bobo-Dioulasso, Burkina Faso
| | - Alain Boulangé
- Unité de Recherche sur les Maladies à Vecteurs et Biodiversité, Centre International de Recherche-Développement sur l’Elevage en zone Subhumide, Bobo-Dioulasso, Burkina Faso
- Unité de Recherche « Trypanosomoses », Institut Pierre Richet, Bouaké, Côte d’Ivoire
- CIRAD, UMR INTERTRYP, Montpellier, France
- INTERTRYP, University of Montpellier, CIRAD, IRD, Montpellier, France
| | - Robert Eustache Hounyèmè
- Unité de Recherche sur les Maladies à Vecteurs et Biodiversité, Centre International de Recherche-Développement sur l’Elevage en zone Subhumide, Bobo-Dioulasso, Burkina Faso
- Unité de Recherche « Trypanosomoses », Institut Pierre Richet, Bouaké, Côte d’Ivoire
| | - Geoffrey Gimonneau
- CIRAD, UMR INTERTRYP, Montpellier, France
- INTERTRYP, University of Montpellier, CIRAD, IRD, Montpellier, France
- Laboratoire National d’Élevage et de Recherches Vétérinaires, Service de Bio-Écologie et Pathologies Parasitaires, Dakar—Hann, Sénégal
| | - Jacques Kaboré
- Unité de Recherche sur les Maladies à Vecteurs et Biodiversité, Centre International de Recherche-Développement sur l’Elevage en zone Subhumide, Bobo-Dioulasso, Burkina Faso
- Unité de Formation et de Recherche en Sciences de la Vie et de la Terre, Université Nazi Boni, Bobo-Dioulasso, Burkina Faso
| | | | - Marc Desquesnes
- CIRAD, UMR INTERTRYP, Montpellier, France
- INTERTRYP, University of Montpellier, CIRAD, IRD, Montpellier, France
- National Veterinary School of Toulouse (ENVT), Toulouse, France
| | - Veerle Lejon
- INTERTRYP, University of Montpellier, CIRAD, IRD, Montpellier, France
| | - Mathurin Koffi
- Laboratoire de Biodiversité et Gestion des Ecosystèmes Tropicaux, Unité de Recherche en Génétique et Épidémiologie Moléculaire, UFR Environnement, Université Jean Lorougnon Guédé, Daloa, Côte d’Ivoire
| | - Vincent Jamonneau
- Unité de Recherche « Trypanosomoses », Institut Pierre Richet, Bouaké, Côte d’Ivoire
- INTERTRYP, University of Montpellier, CIRAD, IRD, Montpellier, France
| | - Sophie Thévenon
- CIRAD, UMR INTERTRYP, Montpellier, France
- INTERTRYP, University of Montpellier, CIRAD, IRD, Montpellier, France
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Minet C, Chantal I, Berthier D. Recent advances in genome editing of bloodstream forms of Trypanosoma congolense using CRISPR-Cas9 ribonucleoproteins: Proof of concept. Exp Parasitol 2023; 252:108589. [PMID: 37516291 DOI: 10.1016/j.exppara.2023.108589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 06/26/2023] [Accepted: 07/24/2023] [Indexed: 07/31/2023]
Abstract
African Animal Trypanosomosis (AAT or Nagana) is a vector-borne disease caused by Trypanosomatidae, genus Trypanosoma. The disease is transmitted by the bite of infected hematophagous insects, mainly tsetse flies but also other blood-sucking insects including stomoxes and tabanids. Although many trypanosome species infect animals, the main agents responsible for this disease with a strong socio-economic and veterinary health impact are Trypanosoma congolense (T. congolense or Tc), Trypanosoma vivax (T.vivax), and to a lesser extent, Trypanosoma brucei brucei (T.brucei brucei or Tbb). These parasites mainly infect livestock, including cattle, in sub-Saharan Africa, with major repercussions in terms of animal productivity and poverty for populations which are often already very poor. As there is currently no vaccine, the fight against the disease is primarily based on diagnosis, treatment and vector control. To develop new tools (particularly therapeutic tools) to fight against the disease, we need to know both the biology and the genes involved in the pathogenicity and virulence of the parasites. To date, unlike for Trypanosoma brucei (T.brucei) or Trypanosoma cruzi (T.cruzi), genome editing tools has been relatively little used to study T. congolense. We present an efficient, reproducible and stable CRISPR-Cas9 genome editing system for use in Tc bloodstream forms (Tc-BSF). This plasmid-free system is based on transient expression of Cas9 protein and the use of a ribonucleoprotein formed by the Cas9 and sgRNA complex. This is the first proof of concept of genome editing using CRISPR-Cas9 ribonucleoproteins on Tc-BSF. This adapted protocol enriches the "toolbox" for the functional study of genes of interest in blood forms of the Trypanosoma congolense. This proof of concept is an important step for the scientific community working on the study of trypanosomes and opens up new perspectives for the control of and fight against animal trypanosomosis.
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Affiliation(s)
- Cécile Minet
- CIRAD, UMR INTERTRYP, F-34398, Montpellier, France; INTERTRYP, Univ Montpellier, CIRAD, IRD, Montpellier, France.
| | - Isabelle Chantal
- CIRAD, UMR INTERTRYP, F-34398, Montpellier, France; INTERTRYP, Univ Montpellier, CIRAD, IRD, Montpellier, France
| | - David Berthier
- CIRAD, UMR INTERTRYP, F-34398, Montpellier, France; INTERTRYP, Univ Montpellier, CIRAD, IRD, Montpellier, France
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Tettey MD, Rojas F, Matthews KR. Extracellular release of two peptidases dominates generation of the trypanosome quorum-sensing signal. Nat Commun 2022; 13:3322. [PMID: 35680928 PMCID: PMC9184580 DOI: 10.1038/s41467-022-31057-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 05/31/2022] [Indexed: 01/22/2023] Open
Abstract
Trypanosomes causing African sleeping sickness use quorum-sensing (QS) to generate transmission-competent stumpy forms in mammalian hosts. This density-dependent process is signalled by oligopeptides that stimulate the signal transduction pathway leading to stumpy formation. Here, using mass spectrometry analysis, we identify peptidases released by trypanosomes and, for 12 peptidases, confirm their extracellular delivery. Thereafter, we determine the contribution of each peptidase to QS signal production using systematic inducible overexpression in vivo, and confirm this activity operates through the physiological QS signalling pathway. Gene knockout of the QS-active peptidases identifies two enzymes, oligopeptidase B and metallocarboxypeptidase 1, that significantly reduce QS when ablated individually. Further, combinatorial gene knockout of both peptidases confirms their dominance in the generation of the QS signal, with peptidase release of oligopeptidase B mediated via an unconventional protein secretion pathway. This work identifies how the QS signal driving trypanosome virulence and transmission is generated in mammalian hosts.
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Affiliation(s)
- Mabel Deladem Tettey
- Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, EH93FL, UK
| | - Federico Rojas
- Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, EH93FL, UK.
- Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, LA1 4AT, UK.
| | - Keith R Matthews
- Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, EH93FL, UK.
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Kangethe RT, Winger EM, Settypalli TBK, Datta S, Wijewardana V, Lamien CE, Unger H, Coetzer TH, Cattoli G, Diallo A. Low Dose Gamma Irradiation of Trypanosoma evansi Parasites Identifies Molecular Changes That Occur to Repair Radiation Damage and Gene Transcripts That May Be Involved in Establishing Disease in Mice Post-Irradiation. Front Immunol 2022; 13:852091. [PMID: 35634275 PMCID: PMC9136415 DOI: 10.3389/fimmu.2022.852091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 04/11/2022] [Indexed: 11/29/2022] Open
Abstract
The protozoan parasite Trypanosoma evansi is responsible for causing surra in a variety of mammalian hosts and is spread by many vectors over a wide geographical area making it an ideal target for irradiation as a tool to study the initial events that occur during infection. Parasites irradiated at the representative doses 100Gy, 140Gy, and 200Gy were used to inoculate BALB/c mice revealing that parasites irradiated at 200Gy were unable to establish disease in all mice. Cytokine analysis of mice inoculated with 200Gy of irradiated parasites showed significantly lower levels of interleukins when compared to mice inoculated with non-irradiated and 100Gy irradiated parasites. Irradiation also differentially affected the abundance of gene transcripts in a dose-dependent trend measured at 6- and 20-hours post-irradiation with 234, 325, and 484 gene transcripts affected 6 hours post-irradiation for 100Gy-, 140Gy- and 200Gy-irradiated parasites, respectively. At 20 hours post-irradiation, 422, 381, and 457 gene transcripts were affected by irradiation at 100Gy, 140Gy, and 200Gy, respectively. A gene ontology (GO) term analysis was carried out for the three representative doses at 6 hours and 20 hours post-irradiation revealing different processes occurring at 20 hours when compared to 6 hours for 100Gy irradiation. The top ten most significant processes had a negative Z score. These processes fall in significance at 140Gy and even further at 200Gy, revealing that they were least likely to occur at 200Gy, and thus may have been responsible for infection in mice by 100Gy and 140Gy irradiated parasites. When looking at 100Gy irradiated parasites 20 hours post-irradiation processes with a positive Z score, we identified genes that were involved in multiple processes and compared their fold change values at 6 hours and 20 hours. We present these genes as possibly necessary for repair from irradiation damage at 6 hours and suggestive of being involved in the establishment of disease in mice at 20 hours post-irradiation. A potential strategy using this information to develop a whole parasite vaccine is also postulated.
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Affiliation(s)
- Richard T. Kangethe
- Animal Production and Health Laboratory, FAO/IAEA Agriculture and Biotechnology Laboratory, IAEA Laboratories Seibersdorf, International Atomic Energy Agency (IAEA), Vienna, Austria
- *Correspondence: Richard T. Kangethe,
| | - Eva M. Winger
- Animal Production and Health Laboratory, FAO/IAEA Agriculture and Biotechnology Laboratory, IAEA Laboratories Seibersdorf, International Atomic Energy Agency (IAEA), Vienna, Austria
| | - Tirumala Bharani K. Settypalli
- Animal Production and Health Laboratory, FAO/IAEA Agriculture and Biotechnology Laboratory, IAEA Laboratories Seibersdorf, International Atomic Energy Agency (IAEA), Vienna, Austria
| | - Sneha Datta
- Animal Production and Health Laboratory, FAO/IAEA Agriculture and Biotechnology Laboratory, IAEA Laboratories Seibersdorf, International Atomic Energy Agency (IAEA), Vienna, Austria
| | - Viskam Wijewardana
- Animal Production and Health Laboratory, FAO/IAEA Agriculture and Biotechnology Laboratory, IAEA Laboratories Seibersdorf, International Atomic Energy Agency (IAEA), Vienna, Austria
| | - Charles E. Lamien
- Animal Production and Health Laboratory, FAO/IAEA Agriculture and Biotechnology Laboratory, IAEA Laboratories Seibersdorf, International Atomic Energy Agency (IAEA), Vienna, Austria
| | - Hermann Unger
- Animal Production and Health Laboratory, FAO/IAEA Agriculture and Biotechnology Laboratory, IAEA Laboratories Seibersdorf, International Atomic Energy Agency (IAEA), Vienna, Austria
| | - Theresa H.T. Coetzer
- Biochemistry, School of Life Sciences, University of KwaZulu-Natal, Pietermaritzburg, South Africa
| | - Giovanni Cattoli
- Animal Production and Health Laboratory, FAO/IAEA Agriculture and Biotechnology Laboratory, IAEA Laboratories Seibersdorf, International Atomic Energy Agency (IAEA), Vienna, Austria
| | - Adama Diallo
- Animal Production and Health Laboratory, FAO/IAEA Agriculture and Biotechnology Laboratory, IAEA Laboratories Seibersdorf, International Atomic Energy Agency (IAEA), Vienna, Austria
- UMR CIRAD INRA, Animal, Santé, Territoires, Risques et Ecosystèmes (ASTRE), Montpellier, France
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Update on relevant trypanosome peptidases: Validated targets and future challenges. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2020; 1869:140577. [PMID: 33271348 DOI: 10.1016/j.bbapap.2020.140577] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 11/09/2020] [Accepted: 11/24/2020] [Indexed: 02/06/2023]
Abstract
Trypanosoma cruzi, the agent of the American Trypanosomiasis, Chagas disease, and Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense, the agents of Sleeping sickness (Human African Trypanosomiasis, HAT), as well as Trypanosoma brucei brucei, the agent of the cattle disease nagana, contain cysteine, serine, threonine, aspartyl and metallo peptidases. The most abundant among these enzymes are the cysteine proteases from the Clan CA, the Cathepsin L-like cruzipain and rhodesain, and the Cathepsin B-like enzymes, which have essential roles in the parasites and thus are potential targets for chemotherapy. In addition, several other proteases, present in one or both parasites, have been characterized, and some of them are also promising candidates for the developing of new drugs. Recently, new inhibitors, with good selectivity for the parasite proteasomes, have been described and are very promising as lead compounds for the development of new therapies for these neglected diseases. This article is part of a Special Issue entitled: "Play and interplay of proteases in health and disease".
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Motta FN, Azevedo CDS, Neves BP, Araújo CND, Grellier P, Santana JMD, Bastos IMD. Oligopeptidase B, a missing enzyme in mammals and a potential drug target for trypanosomatid diseases. Biochimie 2019; 167:207-216. [DOI: 10.1016/j.biochi.2019.10.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 10/15/2019] [Indexed: 12/21/2022]
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Long Y, Cao B, Yu L, Tukayo M, Feng C, Wang Y, Luo D. Angiostrongylus cantonensis cathepsin B-like protease (Ac-cathB-1) is involved in host gut penetration. ACTA ACUST UNITED AC 2015; 22:37. [PMID: 26682577 PMCID: PMC4684300 DOI: 10.1051/parasite/2015037] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Accepted: 11/27/2015] [Indexed: 12/17/2022]
Abstract
Although the global spread of the emerging zoonosis, human angiostrongyliasis, has attracted increasing attention, understanding of specific gene function has been impeded by the inaccessibility of genetic manipulation of the pathogen nematode causing this disease, Angiostrongylus cantonensis. Many parasitic proteases play key roles in host-parasite interactions, but those of A. cantonensis are always expressed as the inactive form in prokaryotic expression systems, thereby impeding functional studies. Hence, a lentiviral system that drives secreted expression of target genes fused to a Myc-His tag was used to obtain recombinant Ac-cathB-1 with biological activity. Although this class of proteases was always reported to function in nutrition and immune evasion in parasitic nematodes, recombinant Ac-cathB-1 was capable of hydrolysis of fibronectin and laminin as well as the extracellular matrix of IEC-6 monolayer, so that the intercellular space of the IEC-6 monolayer increased 5.15 times as compared to the control, while the shape of the adherent cells partly rounded up. This suggests a probable role for this protease in intestinal epithelial penetration. The inhibition of Ac-cathB-1 enzymatic activity with antiserum partly suppressed larval penetration ability in the isolated intestine. Thus, an effective system for heterologous expression of parasite proteases is presented for studying gene function in A. cantonensis; and Ac-cathB-1 was related to larval penetration ability in the host small intestine.
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Affiliation(s)
- Ying Long
- School of Life Sciences, Xiamen University, Fujian 361102, P.R. China - State Key Laboratory of Cellular Stress Biology, Xiamen University, Fujian 361102, P.R. China
| | - Binbin Cao
- School of Life Sciences, Xiamen University, Fujian 361102, P.R. China - State Key Laboratory of Cellular Stress Biology, Xiamen University, Fujian 361102, P.R. China
| | - Liang Yu
- School of Life Sciences, Xiamen University, Fujian 361102, P.R. China - State Key Laboratory of Cellular Stress Biology, Xiamen University, Fujian 361102, P.R. China
| | - Meks Tukayo
- School of Life Sciences, Xiamen University, Fujian 361102, P.R. China - State Key Laboratory of Cellular Stress Biology, Xiamen University, Fujian 361102, P.R. China
| | - Chonglv Feng
- School of Life Sciences, Xiamen University, Fujian 361102, P.R. China - State Key Laboratory of Cellular Stress Biology, Xiamen University, Fujian 361102, P.R. China
| | - Yinan Wang
- Medical College, Xiamen University, Fujian 361102, P.R. China
| | - Damin Luo
- School of Life Sciences, Xiamen University, Fujian 361102, P.R. China - State Key Laboratory of Cellular Stress Biology, Xiamen University, Fujian 361102, P.R. China
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An essential signal peptide peptidase identified in an RNAi screen of serine peptidases of Trypanosoma brucei. PLoS One 2015; 10:e0123241. [PMID: 25816352 PMCID: PMC4376731 DOI: 10.1371/journal.pone.0123241] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 03/01/2015] [Indexed: 02/05/2023] Open
Abstract
The serine peptidases of Trypanosoma brucei have been viewed as potential drug targets. In particular, the S9 prolyl oligopeptidase subfamily is thought to be a good avenue for drug discovery. This is based on the finding that some S9 peptidases are secreted and active in the mammalian bloodstream, and that they are a class of enzyme against which drugs have successfully been developed. We collated a list of all serine peptidases in T. brucei, identifying 20 serine peptidase genes, of which nine are S9 peptidases. We screened all 20 serine peptidases by RNAi to determine which, if any, are essential for bloodstream form T. brucei survival. All S9 serine peptidases were dispensable for parasite survival in vitro, even when pairs of similar genes, coding for oligopeptidase B or prolyl oligopeptidase, were targeted simultaneously. We also found no effect on parasite survival in an animal host when the S9 peptidases oligopeptidase B, prolyl oligopeptidase or dipeptidyl peptidase 8 were targeted. The only serine peptidase to emerge from the RNAi screen as essential was a putative type-I signal peptide peptidase (SPP1). This gene was essential for parasite survival both in vitro and in vivo. The growth defect conferred by RNAi depletion of SPP1 was rescued by expression of a functional peptidase from an RNAi resistant SPP1 gene. However, expression of catalytically inactive SPP1 was unable to rescue cells from the SPP1 depleted phenotype, demonstrating that SPP1 serine peptidase activity is necessary for T. brucei survival.
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Bastos IMD, Motta FN, Grellier P, Santana JM. Parasite prolyl oligopeptidases and the challenge of designing chemotherapeuticals for Chagas disease, leishmaniasis and African trypanosomiasis. Curr Med Chem 2014; 20:3103-15. [PMID: 23514419 PMCID: PMC3778648 DOI: 10.2174/0929867311320250006] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Accepted: 10/16/2012] [Indexed: 11/22/2022]
Abstract
The trypanosomatids Trypanosoma cruzi, Leishmania spp. and Trypanosoma brucei spp. cause Chagas disease, leishmaniasis and human African trypanosomiasis, respectively. It is estimated that over 10 million people worldwide suffer from these neglected diseases, posing enormous social and economic problems in endemic areas. There are no vaccines to prevent these infections and chemotherapies are not adequate. This picture indicates that new chemotherapeutic agents must be developed to treat these illnesses. For this purpose, understanding the biology of the pathogenic trypanosomatid-host cell interface is fundamental for molecular and functional characterization of virulence factors that may be used as targets for the development of inhibitors to be used for effective chemotherapy. In this context, it is well known that proteases have crucial functions for both metabolism and infectivity of pathogens and are thus potential drug targets. In this regard, prolyl oligopeptidase and oligopeptidase B, both members of the S9 serine protease family, have been shown to play important roles in the interactions of pathogenic protozoa with their mammalian hosts and may thus be considered targets for drug design. This review aims to discuss structural and functional properties of these intriguing enzymes and their potential as targets for the development of drugs against Chagas disease, leishmaniasis and African trypanosomiasis.
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Affiliation(s)
- I M D Bastos
- Pathogen-Host Interface Laboratory, Department of Cell Biology, The University of Brasília, Brasília, Brazil
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10
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Canning P, Rea D, Morty RE, Fülöp V. Crystal structures of Trypanosoma brucei oligopeptidase B broaden the paradigm of catalytic regulation in prolyl oligopeptidase family enzymes. PLoS One 2013; 8:e79349. [PMID: 24265767 PMCID: PMC3827171 DOI: 10.1371/journal.pone.0079349] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Accepted: 09/27/2013] [Indexed: 11/18/2022] Open
Abstract
Oligopeptidase B cleaves after basic amino acids in peptides up to 30 residues. As a virulence factor in bacteria and trypanosomatid pathogens that is absent in higher eukaryotes, this is a promising drug target. Here we present ligand-free open state and inhibitor-bound closed state crystal structures of oligopeptidase B from Trypanosoma brucei, the causative agent of African sleeping sickness. These (and related) structures show the importance of structural dynamics, governed by a fine enthalpic and entropic balance, in substrate size selectivity and catalysis. Peptides over 30 residues cannot fit the enzyme cavity, preventing the complete domain closure required for a key propeller Asp/Glu to fix the catalytic His and Arg in the catalytically competent conformation. This size exclusion mechanism protects larger peptides and proteins from degradation. Similar bacterial prolyl endopeptidase and archael acylaminoacyl peptidase structures demonstrate this mechanism is conserved among oligopeptidase family enzymes across all three domains of life.
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Affiliation(s)
- Peter Canning
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Dean Rea
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Rory E. Morty
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Vilmos Fülöp
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
- * E-mail:
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