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Promastigote-to-Amastigote Conversion in Leishmania spp.—A Molecular View. Pathogens 2022; 11:pathogens11091052. [PMID: 36145483 PMCID: PMC9503511 DOI: 10.3390/pathogens11091052] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 09/08/2022] [Accepted: 09/13/2022] [Indexed: 11/28/2022] Open
Abstract
A key factor in the successful infection of a mammalian host by Leishmania parasites is their conversion from extracellular motile promastigotes into intracellular amastigotes. We discuss the physical and chemical triggers that induce this conversion and the accompanying changes at the molecular level crucial for the survival of these intracellular parasites. Special emphasis is given to the reliance of these trypanosomatids on the post-transcriptional regulation of gene expression but also to the role played by protein kinases, chaperone proteins and proteolytic enzymes. Lastly, we offer a model to integrate the transduction of different stress signals for the induction of stage conversion.
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Barral-Veloso L, Melo BCDA, Santos-de-Souza R, Cysne-Finkelstein L, Souza-Silva F, Santos FN, Sousa JFD, Alves CR. Reactivity of sera from dogs living in a leishmaniasis-endemic area to the COOH-terminal region of cysteine proteinase B. Braz J Infect Dis 2020; 24:201-207. [PMID: 32343952 PMCID: PMC9392045 DOI: 10.1016/j.bjid.2020.04.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 04/06/2020] [Accepted: 04/11/2020] [Indexed: 11/01/2022] Open
Abstract
Cysteine proteinases are well-known virulence factors of Leishmania spp. with demonstrated actions in both experimental mouse infection and human infection. However, studies on these enzymes in canine leishmaniasis are scarce. Here, we show, for the first time, the reactivity of sera from dogs living in an endemic area to a recombinant protein from the COOH-terminal region of cysteine B protease. In this work, enzyme-linked immunosorbent assays were performed using a 14kDa rcyspep protein obtained through a pET28-a expression system in Escherichia coli. First, 96-well plates were coated with rcyspep (500ng/well) and incubated with sera from dogs (1:100). Subsequently, IgG antibody detection was performed using rabbit anti-dog IgG antibodies conjugated with peroxidase. Sera from dogs (n=114), including suspect (n=30) and positive (n=50) dogs from a leishmaniasis-endemic area and dogs from a nonendemic area, (n=34), negative for leishmaniasis, were assessed. The results showed that sera from the suspect (42%) and positive (68%) groups responded differently to the antigen titers tested above the cut-off (Optical Density=0.166). This finding suggests that the immune response detected against cyspep may be related to clinical disorders present in these animals. Collectively, the data gathered here suggest that cyspep can sensitize the immune systems of dogs from a leishmaniasis-endemic area to elicit a humoral response, an immunological parameter indicating the contribution of this protein in host-parasite interaction.
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Affiliation(s)
- Laura Barral-Veloso
- Fundação Oswaldo Cruz, Instituto Oswaldo Cruz, Laboratório de Biologia Molecular e Doenças Endêmicas, Rio de Janeiro, RJ, Brazil
| | | | - Raquel Santos-de-Souza
- Fundação Oswaldo Cruz, Instituto Oswaldo Cruz, Laboratório de Biologia Molecular e Doenças Endêmicas, Rio de Janeiro, RJ, Brazil
| | - Léa Cysne-Finkelstein
- Fundação Oswaldo Cruz, Instituto Oswaldo Cruz, Laboratório de Imunoparasitologia, Rio de Janeiro, RJ, Brazil
| | - Franklin Souza-Silva
- Fundação Oswaldo Cruz, Centro de Desenvolvimento Tecnológico em Saúde, Rio de Janeiro, RJ, Brazil
| | - Fernanda Nunes Santos
- Fundação Oswaldo Cruz, Escola Nacional de Saúde Pública Sergio Arouca, Departamento de Ciências Biológicas, Laboratório de Imunodiagnóstico, Rio de Janeiro, RJ, Brazil
| | | | - Carlos Roberto Alves
- Fundação Oswaldo Cruz, Instituto Oswaldo Cruz, Laboratório de Biologia Molecular e Doenças Endêmicas, Rio de Janeiro, RJ, Brazil.
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Insights into the tracking of the cysteine proteinase B COOH-terminal polypeptide of Leishmania (Leishmania) amazonensis by surface plasmon resonance. Parasitol Res 2019; 118:1249-1259. [DOI: 10.1007/s00436-019-06238-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 01/25/2019] [Indexed: 02/06/2023]
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Diupotex M, Martínez-Salazar MB, Escalona-Montaño AR, Zamora-Chimal J, Salaiza-Suazo N, Ruiz-Remigio A, Roldán-Salgado A, Aguirre-García MM, Martínez-Calvillo S, Gaytán P, Becker I. The mKate fluorescent protein expressed by Leishmania mexicana modifies the parasite immunopathogenicity in BALB/c mice. Parasite Immunol 2019; 41:e12608. [PMID: 30500992 DOI: 10.1111/pim.12608] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 11/22/2018] [Accepted: 11/23/2018] [Indexed: 11/27/2022]
Abstract
Parasites have been engineered to express fluorescent reporter proteins, yet the impact of red fluorescent proteins on Leishmania infections remains largely unknown. We analysed the infection outcome of Leishmania mexicana parasites engineered for the constitutive expression of mKate protein and evaluated their immunogenicity in BALB/c mice. Infection of BALB/c mice with mKate transfected L. mexicana (LmexmKate ) parasites caused enlarged lesion sizes, leading to ulceration, and containing more parasites, as compared to LmexWT . The mKate protein showed immunogenic properties inducing antibody production against the mKate protein, as well as enhancing antibody production against the parasite. The augmented lesion sizes and ulcers, together with the more elevated antibody production, were related to an enhanced number of TNF-α and IL-1β producing cells in the infected tissues. We conclude that mKate red fluorescent protein is an immunogenic protein, capable of modifying disease evolution of L. mexicana.
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Affiliation(s)
- Mariana Diupotex
- Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Hospital General de México, Ciudad de México, México
| | - María Berenice Martínez-Salazar
- Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Hospital General de México, Ciudad de México, México
| | - Alma Reyna Escalona-Montaño
- Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Hospital General de México, Ciudad de México, México
| | - Jaime Zamora-Chimal
- Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Hospital General de México, Ciudad de México, México
| | - Norma Salaiza-Suazo
- Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Hospital General de México, Ciudad de México, México
| | - Adriana Ruiz-Remigio
- Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Hospital General de México, Ciudad de México, México
| | | | - María Magdalena Aguirre-García
- Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Hospital General de México, Ciudad de México, México
| | - Santiago Martínez-Calvillo
- Unidad de Biomedicina, Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla, México
| | - Paul Gaytán
- Instituto de Biotecnología-Universidad Nacional Autónoma de México, Cuernavaca, México
| | - Ingeborg Becker
- Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Hospital General de México, Ciudad de México, México
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Koolen HHF, Pral EMF, Alfieri SC, Marinho JVN, Serain AF, Hernández-Tasco AJ, Andreazza NL, Salvador MJ. Antiprotozoal and antioxidant alkaloids from Alternanthera littoralis. PHYTOCHEMISTRY 2017; 134:106-113. [PMID: 27889243 DOI: 10.1016/j.phytochem.2016.11.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 11/14/2016] [Accepted: 11/17/2016] [Indexed: 06/06/2023]
Abstract
Five alkaloids, in addition to hydroxytyrosol and uridine, were isolated from aerial parts of Alternanthera littoralis P. Beauv. Among the isolated compounds, alternamide A was an unusual tricyclic alkaloid with a bridged benzoazepine core. All isolated alkaloids have a catechol moiety, indicating a possible common biosynthetic route. Their structures were established by 1D and 2D NMR spectroscopy in combination with extensive tandem MS experiments by collisional induced dissociation (CID). The antiprotozoal activity of the isolated compounds was assayed against trypomastigote forms of Trypanosoma cruzi and amastigotes of Leishmania amazonensis. Alternamine A was the most active compound, reducing markedly the viability of both parasites. Antioxidant capacities evaluated by ORACFL assay showed that the isolated alkaloids (mainly alternamide B) contributed to the high activity recorded for the ethanolic crude extract; possibly, the catechol moiety present in all structures plays a central role in this result.
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Affiliation(s)
- Hector H F Koolen
- DeMpSter Mass Spectrometry Group, Superior Institute of Health Sciences, Amazonas State University - UEA, 69055-010 Manaus, AM, Brazil; Department of Plant Biology, PPG BTPB and PPG BV, Institute of Biology, University of Campinas - UNICAMP, 13083-970 Campinas, SP, Brazil.
| | - Elizabeth M F Pral
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo - USP, 05508-000 São Paulo, SP, Brazil
| | - Silvia C Alfieri
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo - USP, 05508-000 São Paulo, SP, Brazil
| | - Jane V N Marinho
- Department of Plant Biology, PPG BTPB and PPG BV, Institute of Biology, University of Campinas - UNICAMP, 13083-970 Campinas, SP, Brazil
| | - Alessandra F Serain
- Department of Plant Biology, PPG BTPB and PPG BV, Institute of Biology, University of Campinas - UNICAMP, 13083-970 Campinas, SP, Brazil
| | - Alvaro J Hernández-Tasco
- Department of Plant Biology, PPG BTPB and PPG BV, Institute of Biology, University of Campinas - UNICAMP, 13083-970 Campinas, SP, Brazil
| | - Nathalia L Andreazza
- Department of Plant Biology, PPG BTPB and PPG BV, Institute of Biology, University of Campinas - UNICAMP, 13083-970 Campinas, SP, Brazil
| | - Marcos J Salvador
- Department of Plant Biology, PPG BTPB and PPG BV, Institute of Biology, University of Campinas - UNICAMP, 13083-970 Campinas, SP, Brazil
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Pitaluga AN, Moreira MEC, Traub-Csekö YM. A putative role for inosine 5' monophosphate dehydrogenase (IMPDH) in Leishmania amazonensis programmed cell death. Exp Parasitol 2014; 149:32-8. [PMID: 25499513 DOI: 10.1016/j.exppara.2014.12.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 11/25/2014] [Accepted: 12/04/2014] [Indexed: 11/18/2022]
Abstract
Leishmania amazonensis undergoes apoptosis-like programmed cell death (PCD) under heat shock conditions. We identified a potential role for inosine 5' monophosphate dehydrogenase (IMPDH) in L. amazonensis PCD. Trypanosomatids do not have a "de novo" purine synthesis pathway, relying on the salvage pathway for survival. IMPDH, a key enzyme in the purine nucleotide pathway, is related to cell growth and apoptosis. Since guanine nucleotide depletion triggers cell cycle arrest and apoptosis in several organisms we analyzed the correlation between IMPDH and apoptosis-like death in L. amazonensis. The L. amazonensis IMPDH inhibition effect on PCD was evaluated through gene expression analysis, mitochondrial depolarization and detection of Annexin-V labeled parasites. We demonstrated a down-regulation of impdh expression under heat shock treatment, which mimics the natural mammalian host infection. Also, IMPDH inhibitors ribavirin and mycophenolic acid (MPA) prevented cell growth and generated an apoptosis-like phenotype in sub-populations of L. amazonensis promastigotes. Our results are in accordance with previous results showing that a subpopulation of parasites undergoes apoptosis-like cell death in the nutrient poor environment of the vector gut. Here, we suggest the involvement of purine metabolism in previously observed apoptosis-like cell death during Leishmania infection.
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Affiliation(s)
- A N Pitaluga
- Laboratório de Biologia Molecular de Parasitas e Vetores, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, Brazil.
| | - M E C Moreira
- Divisão de Medicina Experimental, Instituto Nacional de Câncer, Rio de Janeiro, Brazil
| | - Y M Traub-Csekö
- Laboratório de Biologia Molecular de Parasitas e Vetores, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, Brazil
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Austrup J, Ntais P, Christodoulou V, Dedet JP, Pratlong F, Antoniou M. Frequency of MDR1-related p-gp overexpression in Greek Leishmania isolates. Parasitol Res 2014; 113:1225-32. [PMID: 24504599 DOI: 10.1007/s00436-014-3761-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Accepted: 01/10/2014] [Indexed: 11/29/2022]
Abstract
In this work, we investigated Greek Leishmania isolates (n = 70) for their individual MDR1-gene-related p-gp (belonging to the ABC-B subfamily of permeases) expression levels by means of flow cytometric analysis of Rhodamine 123 extrusion kinetics. Of all used isolates, 5.71% express this drug-extruding ABC-transporter at alarming levels and are distributed widely over the country. Some 33% of all examined isolates originated on the island of Crete though none of the strains showed vastly elevated p-gp extrusion activity, indicating a reasonable implementation of anti-leishmanial compounds in this part of the country. Compared to isolates obtained from canine tissue, human Leishmania isolates were superior both in size and in subcellular differentiation in flow cytometry. Furthermore, a specific t test confirmed verapamil hydrochloride to be a highly potent p-gp reversal agent with p < 0.0001. In a second test series, the loading of Leishmania with Rhodamine 123 was moreover reduced when occurring under influence of verapamil hydrochloride, a known p-gp reversal agent, indicating an ATP-dependant influx of the fluorescent dye and therewith the drug itself. In a final, third experiment series, it was shown that Sb(V) does not act upon the promastigote form of Leishmania.
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Affiliation(s)
- Johannes Austrup
- Center of Anatomy, Institute II, Laboratory for Medical and Molecular Parasitology, Medical School, University of Cologne, Cologne, Germany,
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Biyani N, Madhubala R. Quantitative proteomic profiling of the promastigotes and the intracellular amastigotes of Leishmania donovani isolates identifies novel proteins having a role in Leishmania differentiation and intracellular survival. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2012; 1824:1342-50. [DOI: 10.1016/j.bbapap.2012.07.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Revised: 07/20/2012] [Accepted: 07/22/2012] [Indexed: 12/23/2022]
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Passero LFD, Da Costa Bordon MLA, De Carvalho AK, Martins LM, Corbett CEP, Laurenti MD. Exacerbation of Leishmania (Viannia) shawi infection in BALB/c mice after immunization with soluble antigen from amastigote forms. APMIS 2010; 118:973-81. [PMID: 21091779 DOI: 10.1111/j.1600-0463.2010.02679.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The present study aimed to evaluate the effects of immunization with soluble amastigote (AmaAg) and promastigote (ProAg) antigens from Leishmania (Viannia) shawi on the course of infection in BALB/c mice. After immunization with AmaAg, the challenged group showed greater lesion size and parasite load in the skin and lymph nodes, associated with diminished interleukin (IL)-2, IL-4, IL-10, interferon (IFN)-γ and nitrate levels in the supernatant of lymph node cell cultures, together with increases in transforming growth factor (TGF)-β concentrations and humoral immune response. In contrast, immunization with ProAg led to smaller lesion size with reduced numbers of viable parasites in the skin. Protection was associated with increases in IL-12, IFN-γ, TGF-β and nitrates and decreases in IL-4 and IL-10 levels. Concerning humoral immune response, a significant reduction in anti-leishmania immunoglobulin G was verified in the ProAg-challenged group. Analysis of these results suggests that AmaAg induced a suppressive cellular immune response in mice, favouring the spread of infection, whereas ProAg induced partial protection associated with increased cellular immune response.
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Alcolea PJ, Alonso A, Gómez MJ, Sánchez-Gorostiaga A, Moreno-Paz M, González-Pastor E, Toraño A, Parro V, Larraga V. Temperature increase prevails over acidification in gene expression modulation of amastigote differentiation in Leishmania infantum. BMC Genomics 2010; 11:31. [PMID: 20074347 PMCID: PMC2845110 DOI: 10.1186/1471-2164-11-31] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2009] [Accepted: 01/14/2010] [Indexed: 01/06/2023] Open
Abstract
Background The extracellular promastigote and the intracellular amastigote stages alternate in the digenetic life cycle of the trypanosomatid parasite Leishmania. Amastigotes develop inside parasitophorous vacuoles of mammalian phagocytes, where they tolerate extreme environmental conditions. Temperature increase and pH decrease are crucial factors in the multifactorial differentiation process of promastigotes to amastigotes. Although expression profiling approaches for axenic, cell culture- and lesion-derived amastigotes have already been reported, the specific influence of temperature increase and acidification of the environment on developmental regulation of genes has not been previously studied. For the first time, we have used custom L. infantum genomic DNA microarrays to compare the isolated and the combined effects of both factors on the transcriptome.
Results Immunofluorescence analysis of promastigote-specific glycoprotein gp46 and expression modulation analysis of the amastigote-specific A2 gene have revealed that concomitant exposure to temperature increase and acidification leads to amastigote-like forms. The temperature-induced gene expression profile in the absence of pH variation resembles the profile obtained under combined exposure to both factors unlike that obtained for exposure to acidification alone. In fact, the subsequent fold change-based global iterative hierarchical clustering analysis supports these findings. Conclusions The specific influence of temperature and pH on the differential regulation of genes described in this study and the evidence provided by clustering analysis is consistent with the predominant role of temperature increase over extracellular pH decrease in the amastigote differentiation process, which provides new insights into Leishmania physiology.
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Affiliation(s)
- Pedro J Alcolea
- Departamento de Microbiología Molecular y Biología de las Infecciones, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas (CSIC), calle Ramiro de Maeztu, 9, 28040, Madrid, Spain
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Nasereddin A, Schweynoch C, Schonian G, Jaffe CL. Characterization of Leishmania (Leishmania) tropica axenic amastigotes. Acta Trop 2010; 113:72-9. [PMID: 19782652 DOI: 10.1016/j.actatropica.2009.09.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2009] [Revised: 08/13/2009] [Accepted: 09/18/2009] [Indexed: 10/20/2022]
Abstract
Optimum conditions for generating Leishmania (Leishmania) tropica axenic amastigotes (AxA) in culture were determined, pH 5.5/36 degrees C, and the parasites characterized by different techniques, including light microscopy, macrophage infection, stage specific antigen expression and differential display. AxA were morphologically similar to amastigotes and 15.5-fold more infective than stationary phase promastigotes for mouse peritoneal macrophages. Western blotting with promastigote stage specific monoclonal antibodies to either lipophosphoglycan (T2) or a 60 kDa flagella antigen (F3) showed a dramatic decrease in antigen expression when AxA were compared to promastigotes. Similarly F3 gave strong immune fluorescent staining of the promastigote flagellum, but no fluorescence was detected when AxA were examined. Conversely, Western blotting with the amastigote specific monoclonal antibody (T16) showed that this antigen is more highly expressed in AxA than promastigotes. Differential display-PCR was used to identify several parasite genes showing stage specific expression. One gene selectively expressed by AxA was partially sequenced and identified as Leishmania (L.) tropicaamastin. Amastigote specific expression of this gene was further confirmed by reverse transcriptase-PCR (RT-PCR) using AxA and infected macrophages. No amastin expression was observed with promastigotes. Expression of the cysteine protease B (cpb) and protein kinase A catalytic isoform 1 subunit (pkac1) in promastigotes and AxA was also examined by RT-PCR. Pkac1 was strongly expressed by promastigotes, while cpb expression was only seen with AxA or infected macrophages. L. (L.) tropica AxA will prove useful for further studies on parasite differentiation and gene regulation, as well as for drug screening.
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Rebello KM, Côrtes LMC, Pereira BAS, Pascarelli BMO, Côrte-Real S, Finkelstein LC, Pinho RT, d'Avila-Levy CM, Alves CR. Cysteine proteinases from promastigotes of Leishmania (Viannia) braziliensis. Parasitol Res 2009; 106:95-104. [PMID: 19777260 DOI: 10.1007/s00436-009-1632-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2009] [Accepted: 09/04/2009] [Indexed: 11/30/2022]
Abstract
Leishmania (Viannia) braziliensis is the major causative agent of American tegumentary leishmaniasis, a disease that has a wide geographical distribution and is a severe public health problem. The cysteine proteinase B (CPB) from Leishmania spp. represents an important virulence factor. In this study, we characterized and localized cysteine proteinases in L. (V.) braziliensis promastigotes. By a combination of triton X-114 extraction, concanavalin A-affinity, and ion exchange chromatographies, we obtained an enriched fraction of hydrophobic proteins rich in mannose residues. This fraction contained two proteinases of 63 and 43 kDa, which were recognized by a CPB antiserum, and were partially sensitive to E-64 in enzymatic assays with the peptide Glu-Phe-Leu. In confocal microscopy, the CPB homologues localized in the peripheral region of the parasite. This data together with direct agglutination and flow cytometry assays suggest a surface localization of the CPB homologues. The incubation of intact promastigotes with phospholipase C reduced the number of CPB-positive cells, while anti-cross-reacting determinant and anti-CPB antisera recognized two polypeptides (63 and 43 kDa) derived from phospholipase C treatment, suggesting that some CPB isoforms may be glycosylphosphatidylinositol-anchored. Collectively, our results suggest the presence of CPB homologues in L. braziliensis surface and highlight the need for further studies on L. braziliensis cysteine proteinases, which require enrichment methods for enzymatic detection.
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Affiliation(s)
- Karina M Rebello
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz (IOC), FIOCRUZ, Manguinhos, 21045-900, Rio de Janeiro, RJ, Brazil
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13
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Babalola OO, Adekunle IM, Okonji RE, Ejim-Eze EE, Terebo O. Selected heavy metals in blood of male Nigerian smokers. Pak J Biol Sci 2009; 10:3730-3. [PMID: 19093492 DOI: 10.3923/pjbs.2007.3730.3733] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Lead, cadmium and zinc levels were determined in the blood of 47 all male smokers (age range, 19-56 years). The subjects were classified into 4 subgroups based on the number of years of smoking, namely: 1-5, 6-10, 11-15 years, >16 years. Thirty all male non-smokers serves as the control. The weight, height and body mass indexes of all subjects were noted in addition to other information obtained through structured questionnaire. Those that were likely to be exposed to any of these metals either occupationally or through other life style habits were excluded from the study. The mean values of blood lead (BPb), blood cadmium (BCd) and blood zinc (BZn) in male smokers (n=47) were 43.26 +/- 4.28, 98.21 +/- 6.39 and 104.84 +/- 3.66 microg dL(-1), respectively while the corresponding mean values for these parameters in the non smokers (n = 30) were 32.44 +/- 3.02, 76.51 +/- 4.59 and 90.38 +/- 2.55 microg dL(-1), respectively. The smokers have statistically significant higher BPb, BCd and BZn than the non-smokers (p < 0.001, p < 0.001 and p < 0.001, respectively). The results appear to confirm the presence of these metals as component of cigarette and agree with similar findings from literature. Consequently, it is probable that high level of these metals in blood of smokers is from tobacco smoking. Additionally it appears that the number of years of smoking has nothing to do with the level of these metals in smokers' blood.
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Affiliation(s)
- O O Babalola
- Department of Biochemistry, Faculty of Science, Obafemi Awolowo University, Ile Ife, Nigeria
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. SM, . RC, . BM, . AB. Radiation Induced Alterations in Membrane Fluidity, Microtubular Structure, Glycoconjugates and Protein in Leishmania donovani. ACTA ACUST UNITED AC 2006. [DOI: 10.3923/jp.2006.48.58] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Alves CR, Corte-Real S, Bourguignon SC, Chaves CS, Saraiva EMB. Leishmania amazonensis: early proteinase activities during promastigote-amastigote differentiation in vitro. Exp Parasitol 2004; 109:38-48. [PMID: 15639138 DOI: 10.1016/j.exppara.2004.10.005] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2004] [Revised: 10/22/2004] [Accepted: 10/29/2004] [Indexed: 11/23/2022]
Abstract
Leishmania proteinase activity is known as parasite differentiation marker, and has been considered relevant for leishmanial survival and virulence. These properties suggest that Leishmania proteinases can be promising targets for development of anti-leishmania drugs. Here, we analyze the activities of four proteinases during the early phase of the Leishmania amazonensis promastigotes differentiation into amastigotes induced by heat shock. We have examined activities of cysteine-, metallo-, serine-, and aspartic-proteinase by hydrolysis of specific chromogenic substrates at pH 5.0 and at the optimal pH for each enzyme. Our results show that metallo-, serine-, and aspartic-proteinases activities were down-regulated during the shock-induced transformation of promastigotes into amastigotes. In contrast, cysteine-proteinase activity increased concomitantly with the promastigote differentiation. Immunocytochemical localization using two anti-cysteine-proteinase monospecific rabbit antibodies detected the enzyme in several cell compartments of both parasite stages. Our results show different proteinase activity modulation and expression during the early phases of the shock-induced parasite transformation.
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Affiliation(s)
- C R Alves
- Departamento Bioquímica e Biologia Molecular, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, RJ, Brazil.
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