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16. Antibody Repertoires Identify β-Tubulin as a Host Protective Parasite Antigen in Mice Infected With Trypanosoma cruzi

Author

Montalvão, Fabricio, primary, Nascimento, Danielle Oliveira, additional, Nunes, Marise P., additional, Koeller, Carolina M., additional, Morrot, Alexandre, additional, Lery, Leticia Miranda S., additional, Bisch, Paulo M., additional, Teixeira, Santuza M. R., additional, Vasconcellos, Rita, additional, Freire-de-Lima, Leonardo, additional, Lopes, Marcela F., additional, Heise, Norton, additional, DosReis, George A., additional, and Freire-de-Lima, Célio Geraldo, additional

Published
2018
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17. Acidocalcisomes as calcium- and polyphosphate-storage compartments during embryogenesis of the insect rhodnius prolixus stahl

Author

Ramos, Isabela Barbosa, Gomes, Fabio Mendonça, Koeller, Carolina Macedo, Saito, Katsuharu, Heise, Norton, Masuda, Hatisaburo, Docampo, Roberto, Souza, Wanderley de, Machado, Ednildo de Alcântara, and Miranda, Kildare Rocha de

Abstract

Submitted by Lívia Oliveira (livia.oliveira2@hotmail.com) on 2012-06-22T13:18:03Z No. of bitstreams: 1 Plos One,v.6,n11, e27276, 2011.pdf: 1347454 bytes, checksum: b0ee3f52902baf6ce0e14aa8450c325d (MD5) Approved for entry into archive by Regina Mello(mrmello@inmetro.gov.br) on 2012-06-25T16:18:11Z (GMT) No. of bitstreams: 1 Plos One,v.6,n11, e27276, 2011.pdf: 1347454 bytes, checksum: b0ee3f52902baf6ce0e14aa8450c325d (MD5) Made available in DSpace on 2012-06-27T18:32:38Z (GMT). No. of bitstreams: 1 Plos One,v.6,n11, e27276, 2011.pdf: 1347454 bytes, checksum: b0ee3f52902baf6ce0e14aa8450c325d (MD5) Previous issue date: 2011 Background: The yolk of insect eggs is a cellular domain specialized in the storage of reserve components for embryo development. The reserve macromolecules are stored in different organelles and their interactions with the embryo cells are mostly unknown. Acidocalcisomes are lysosome-related organelles characterized by their acidic nature, high electron density and large content of polyphosphate bound to several cations. In this work, we report the presence of acidocalcisome-like organelles in eggs of the insect vector Rhodnius prolixus. Methodology/Principal findings: Characterization of the elemental composition of electron-dense vesicles by electron probe X-ray microanalysis revealed a composition similar to that previously described for acidocalcisomes. Following subcellular fractionation experiments, fractions enriched in acidocalcisomes were obtained and characterized. Immunofluorescence showed that polyphosphate polymers and the vacuolar proton translocating pyrophosphatase (V-H+-PPase, considered as a marker for acidocalcisomes) are found in the same vesicles and that these organelles are mainly localized in the egg cortex. Polyphosphate quantification showed that acidocalcisomes contain a significant amount of polyphosphate detected at day-0 eggs. Elemental analyses of the egg fractions showed that 24.560.65% of the egg calcium are also stored in such organelles. During embryogenesis, incubation of acidocalcisomes with acridine orange showed that these organelles are acidified at day-3 (coinciding with the period of yolk mobilization) and polyphosphate quantification showed that the levels of polyphosphate tend to decrease during early embryogenesis, being approximately 30% lower at day-3 compared to day-0 eggs. Conclusions: We found that acidocalcisomes are present in the eggs and are the main storage compartments of polyphosphate and calcium in the egg yolk. As such components have been shown to be involved in a series of dynamic events that may control embryo growth, results reveal the potential involvement of a novel organelle in the storage and mobilization of inorganic elements to the embryo cells. 11 p. : il.

Published
2011

18. The Sphingolipid Biosynthetic Pathway Is a Potential Target for Chemotherapy against Chagas Disease

Author

Koeller, Carolina Macedo and Heise, Norton

Subjects
Article Subject, parasitic diseases
Abstract

The protozoan parasite Trypanosoma cruzi is the causative agent of human Chagas disease, for which there currently is no cure. The life cycle of T. cruzi is complex, including an extracellular phase in the triatomine insect vector and an obligatory intracellular stage inside the vertebrate host. These phases depend on a variety of surface glycosylphosphatidylinositol-(GPI-) anchored glycoconjugates that are synthesized by the parasite. Therefore, the surface expression of GPI-anchored components and the biosynthetic pathways of GPI anchors are attractive targets for new therapies for Chagas disease. We identified new drug targets for chemotherapy by taking the available genome sequence information and searching for differences in the sphingolipid biosynthetic pathways (SBPs) of mammals and T. cruzi. In this paper, we discuss the major steps of the SBP in mammals, yeast and T. cruzi, focusing on the IPC synthase and ceramide remodeling of T. cruzi as potential therapeutic targets for Chagas disease.

Published
2011
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19. Capsular polysaccharides from Cryptococcus neoformans modulate production of neutrophil extracellular traps (NETs) by human neutrophils

Author

Rocha, Juliana D. B., primary, Nascimento, Michelle T. C., additional, Decote-Ricardo, Debora, additional, Côrte-Real, Suzana, additional, Morrot, Alexandre, additional, Heise, Norton, additional, Nunes, Marise P., additional, Previato, José Osvaldo, additional, Mendonça-Previato, Lucia, additional, DosReis, George A., additional, Saraiva, Elvira M., additional, and Freire-de-Lima, Célio G., additional

Published
2015
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20. 2´,3´-Dialdehyde of ATP, ADP, and Adenosine Inhibit HIV-1 Reverse Transcriptase and HIV-1 Replication

Author

Schachter, Julieta, primary, Valadao, Ana, additional, Aguiar, Renato, additional, Barreto-de-Souza, Victor, additional, Rossi, Atila, additional, Arantes, Pablo, additional, Verli, Hugo, additional, Quintana, Paula, additional, Heise, Norton, additional, Tanuri, Amilcar, additional, Bou-Habib, Dumith, additional, and Persechini, Pedro, additional

Published
2014
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21. Golgi UDP-GlcNAc:Polypeptide O -α- N -Acetyl- d -Glucosaminyltransferase 2 (TcOGNT2) Regulates Trypomastigote Production and Function in Trypanosoma cruzi

Author

Koeller, Carolina M., primary, van der Wel, Hanke, additional, Feasley, Christa L., additional, Abreu, Fernanda, additional, da Rocha, Juliana Dutra Barbosa, additional, Montalvão, Fabrício, additional, Fampa, Patrícia, additional, dos Reis, Flávia C. G., additional, Atella, Georgia C., additional, Souto-Padrón, Thaís, additional, West, Christopher M., additional, and Heise, Norton, additional

Published
2014
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34. Infection with Leishmania major Induces a Cellular Stress Response in Macrophages.

Author

Filardy, Alessandra A., Costa-da-Silva, Ana Caroline, Koeller, Carolina M., Guimarães-Pinto, Kamila, Ribeiro-Gomes, Flávia L., Lopes, Marcela F., Heise, Norton, Freire-de-Lima, Célio G., Nunes, Marise P., and DosReis, George A.

Subjects
LEISHMANIA major, PROTOZOAN diseases, MACROPHAGES, LABORATORY mice, REACTIVE oxygen species, INFLAMMATION, N-terminal residues, PROTEIN kinases
Abstract

We investigated early cellular responses induced by infection with Leishmania major in macrophages from resistant C57/BL6 mice. Infection increased production of reactive oxygen species by resident, but not inflammatory peritoneal macrophages. In addition, infection increased activation of stress-activated protein kinases/c-Jun N-terminal kinases (SAPK/JNK) in resident, but not in inflammatory peritoneal macrophages. Infection also increased expression of membrane and soluble FasL, but infected macrophages remained viable after 48 h. Infection increased secretion of cytokines/chemokines TNF-α, IL-6, TIMP-1, IL-1RA, G-CSF, TREM, KC, MIP-1α, MIP-1β, MCP-1, and MIP-2 in resident macrophages. Addition of antioxidants deferoxamine and N-acetylcysteine reduced ROS generation and JNK activation. Addition of antioxidants or JNK inhibitor SP600125 reduced secretion of KC. Furthermore, treatment with antioxidants or JNK inhibitor also reduced intracellular parasite replication. These results indicated that infection triggers a rapid cellular stress response in resident macrophages which induces proinflammatory signals, but is also involved in parasite survival and replication in host macrophages. [ABSTRACT FROM AUTHOR]

Published
2014
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43. Characterization of novel structures of mannosylinositolphosphorylceramides from the yeast forms of Sporothrix schenckii.

Author

y Penha, Carla V. Loureiro, Todeschini, Adriane R., Lopes-Bezerra, Leila M., Wait, Robin, Jones, Christopher, Mattos, Katherine A., Heise, Norton, Mendonça-Previato, Lucia, and Previato, Jose O.

Subjects
INOSITOL, YEAST, OLIGOSACCHARIDES
Abstract

Novel structures of glycoinositolphosphorylceramide (GIPC) from the infective yeast form of Sporothrix schenckii were determined by methylation analysis, mass spectrometry and NMR spectroscopy. The lipid portion was characterized as a ceramide composed of C-18 phytosphingosine N-acylated by either 2-hydroxylignoceric acid (80%), lignoceric (15%) or 2,3-dihydroxylignoceric acids (5%). The ceramide was linked through a phosphodiester to myo-inositol (Ins) which is substituted on position O-6 by an oligomannose chain. GIPC-derived Ins oligomannosides were liberated by ammonolysis and characterized as: &figf5; These structures comprise a novel family of fungal GIPC, as they contain the Manpα1→6Ins substructure, which has not previously been characterized unambigously, and may be acylated with a 2,3 dihydroxylignoceric fatty acid, a feature hitherto undescribed in fungal lipids. [ABSTRACT FROM AUTHOR]

Published
2001
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44. Golgi UDP-GlcNAc:Polypeptide O-a-N-Acetyl-d-Glucosaminyltransferase 2 (TcOGNT2) Regulates Trypomastigote Production and Function in Trypanosoma cruzi

Author

Koeller, Carolina M., van der Wel, Hanke, Feasley, Christa L., Abreu, Fernanda, da Rocha, Juliana Dutra Barbosa, Montalvão, Fabrício, Fampa, Patrícia, dos Reis, Flávia C. G., Atella, Georgia C., Souto-Padrón, Thaís, West, Christopher M., and Heise, Norton

Abstract

ABSTRACTAll life cycle stages of the protozoan parasite Trypanosoma cruziare enveloped by mucin-like glycoproteins which, despite major changes in their polypeptide cores, are extensively and similarly O-glycosylated. O-Glycan biosynthesis is initiated by the addition of aGlcNAc to Thr in a reaction catalyzed by Golgi UDP-GlcNAc:polypeptide O-a-N-acetyl-d-glucosaminyltransferases (ppaGlcNAcTs), which are encoded by TcOGNT1and TcOGNT2. We now directly show that TcOGNT2 is associated with the Golgi apparatus of the epimastigote stage and is markedly downregulated in both differentiated metacyclic trypomastigotes (MCTs) and cell culture-derived trypomastigotes (TCTs). The significance of downregulation was examined by forced continued expression of TcOGNT2, which resulted in a substantial increase of TcOGNT2 protein levels but only modestly increased ppaGlcNAcT activity in extracts and altered cell surface glycosylation in TCTs. Constitutive TcOGNT2 overexpression had no discernible effect on proliferating epimastigotes but negatively affected production of both types of trypomastigotes. MCTs differentiated from epimastigotes at a low frequency, though they were apparently normal based on morphological and biochemical criteria. However, these MCTs exhibited an impaired ability to produce amastigotes and TCTs in cell culture monolayers, most likely due to a reduced infection frequency. Remarkably, inhibition of MCT production did not depend on TcOGNT2 catalytic activity, whereas TCT production was inhibited only by active TcOGNT2. These findings indicate that TcOGNT2 downregulation is important for proper differentiation of MCTs and functioning of TCTs and that TcOGNT2 regulates these functions by using both catalytic and noncatalytic mechanisms.

Published
2014
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45. Na+-ATPase and protein kinase C are targets to 1-O-hexadecylphosphocoline (miltefosine) in Trypanosoma cruzi

Author

Saraiva, Victor Barbosa, Wengert, Mira, Gomes-Quintana, Elaine, Heise, Norton, and Caruso-Neves, Celso

Subjects
*SODIUM/POTASSIUM ATPase, *PROTEIN kinase C, *TRYPANOSOMA cruzi, *FUROSEMIDE, *ENZYME inhibitors, *CELL membranes
Abstract

Abstract: Miltefosine has been shown to be a very active compound against Trypanosoma cruzi. Here, we evaluated the effects of miltefosine on the activity of the Na+-ATPase and protein kinase C (PKC) present in the plasma membrane of T. cruzi. Furosemide (2mM), a specific inhibitor of Na+-ATPase, abolished the growth of T. cruzi showing a crucial role of this enzyme to parasite growth. Miltefosine inhibited the Na+-ATPase activity with IC50 =18±5μgmL−1. This effect was shown to be reversible, dependent on the pH and Ca2+. The inhibition was not observed when the membranes were solubilized with 0.1% deoxycholate, suggesting that the interaction between the enzyme and membrane phospholipids might be important for the drug effect. Miltefosine also inhibited the parasite PKC activity, but through a Na+-ATPase-independent way. Altogether the results indicate that miltefosine inhibits T. cruzi growth through, at least in part, the inhibition of both Na+-ATPase and PKC activities. [Copyright &y& Elsevier]

Published
2009
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46. Glycoinositolphospholipid from Trypanosoma cruzi: Structure, Biosynthesis and Immunobiology.

Author

Previato, Jose O., Wait, Robin, Jones, Christopher, DosReis, George A., Todeschini, Adriane R., Heise, Norton, and Previato, Lucia Mendonça

Subjects
*TRYPANOSOMA cruzi, *PHOSPHOLIPIDS, *BIOSYNTHESIS, *PARASITES, *PATHOGENIC protozoa, *CYTOLOGY
Abstract

Studies the biosynthesis of glycoinositolphospholipids (GPIL) found in the surface of trypanosoma cruzi, a pathogenic protozoan parasite. Role of the GPIL in the cell biology and pathogenicity of t. cruzi; Lipid composition of t. cruzi GPIL; Role of t. cruzi GIPL in T and B cell activation.

Published
2004
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47. Molecular analysis of a UDP-GlcNAc:polypeptide alpha-N-acetylglucosaminyltransferase implicated in the initiation of mucin-type O-glycosylation in Trypanosoma cruzi.

Author

Heise N, Singh D, van der Wel H, Sassi SO, Johnson JM, Feasley CL, Koeller CM, Previato JO, Mendonça-Previato L, and West CM

Subjects
Animals, Dictyostelium genetics, Dictyostelium metabolism, Genome, Protozoan, Glycosylation, Leishmania metabolism, Protein Processing, Post-Translational, Protozoan Proteins genetics, Trypanosoma cruzi genetics, Uridine Diphosphate metabolism, Mucins metabolism, N-Acetylglucosaminyltransferases metabolism, Protozoan Proteins metabolism, Trypanosoma cruzi metabolism
Abstract

Trypanosoma cruzi, the causative agent of Chagas disease, is surrounded by a mucin coat that plays important functions in parasite survival/invasion and is extensively O-glycosylated by Golgi and cell surface glycosyltransferases. The addition of the first sugar, alpha-N-acetylglucosamine (GlcNAc) linked to Threonine (Thr), is catalyzed by a polypeptide alpha-GlcNAc-transferase (pp-alphaGlcNAcT) which is unstable to purification. Here, a comparison of the genomes of T. cruzi and Dictyostelium discoideum, an amoebazoan which also forms this linkage, identified two T. cruzi genes (TcOGNT1 and TcOGNT2) that might encode this activity. Though neither was able to complement the Dictyostelium gene, expression in the trypanosomatid Leishmania tarentolae resulted in elevated levels of UDP-[(3)H]GlcNAc:Thr-peptide GlcNAc-transferase activity and UDP-[(3)H]GlcNAc breakdown activity. The ectodomain of TcOGNT2 was expressed and the secreted protein was found to retain both activities after extensive purification away from other proteins and the endogenous activity. Product analysis showed that (3)H was transferred as GlcNAc to a hydroxyamino acid, and breakdown was due to hydrolysis. Both activities were specific for UDP-GlcNAc relative to UDP-GalNAc and were abolished by active site point mutations that inactivate a related Dictyostelium enzyme and distantly related animal pp-alphaGalNAcTs. The peptide preference and the alkaline pH optimum were indistinguishable from those of the native activity in T. cruzi microsomes. The results suggest that mucin-type O-glycosylation in T. cruzi is initiated by conserved members of CAZy family GT60, which is homologous to the GT27 family of animal pp-alphaGalNAcTs that initiate mucin-type O-glycosylation in animals.

Published
2009
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