A5012544526- Trypanosoma species research and implications
- Carbohydrate Chemistry and Synthesis
- Glycosylation and Glycoproteins Research
- Research on Leishmaniasis Studies
- Fungal Infections and Studies
- Antifungal resistance and susceptibility
- Lysosomal Storage Disorders Research
- Polysaccharides and Plant Cell Walls
- Drug Transport and Resistance Mechanisms
- Plant-Microbe Interactions and Immunity
- Toxin Mechanisms and Immunotoxins
- Synthesis and Biological Evaluation
- Biochemical and Molecular Research
- Galectins and Cancer Biology
- Legume Nitrogen Fixing Symbiosis
- Nail Diseases and Treatments
- Immune Cell Function and Interaction
- Enzyme Production and Characterization
- Piperaceae Chemical and Biological Studies
- Yeasts and Rust Fungi Studies
- Plant Pathogenic Bacteria Studies
- Phytochemical compounds biological activities
- Plant Pathogens and Fungal Diseases
- Monoclonal and Polyclonal Antibodies Research
- Sphingolipid Metabolism and Signaling
Universidade Federal do Rio de Janeiro
2016-2025
Instituto de Biofísica Carlos Chagas Filho
2002-2024
Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro
2010-2023
Fundação Carlos Chagas
2002-2021
Instituto di Biofisica
2010
Instituto Butantan
2010
Adaptimmune (United Kingdom)
2010
National Institute for Biological Standards and Control
1997-2004
Universidade Federal Rural do Rio de Janeiro
2004
Universidade do Estado do Rio de Janeiro
2002
Abstract TLRs function as pattern recognition receptors in mammals and play an essential role the of microbial components. We found that injection glycoinositolphospholipids (GIPLs) from Trypanosoma cruzi into peritoneal cavity mice induced neutrophil recruitment a TLR4-dependent manner: GIPL TLR4-deficient strain (C57BL/10ScCr) caused no inflammatory response. In contrast, TLR2 knockout mice, chemoattraction did not differ significantly seen wild-type controls. GIPL-induced attraction MIP-2...
In the present study, we characterized in vitro modulation of NETs (neutrophil extracellular traps) induced human neutrophils by opportunistic fungus Cryptococcus neoformans, evaluating participation capsular polysaccharides glucuronoxylomanan (GXM) and glucuronoxylomannogalactan (GXMGal) this phenomenon. The mutant acapsular strain CAP67 polysaccharide GXMGal NET production. contrast, wild-type major GXM did not induce release. addition, C. neoformans inhibited PMA-induced Additionally,...
Burkholderia kururiensis M130 is one of the few rice endophytic diazotrophic bacteria identified thus far which able to enhance growth rice. To date, very little known how strain and other endophytes enter colonize plants. Here, we genes that are differentially regulated in presence plant extract. A genetic screening a promoter probe transposon mutant genome bank RNAseq analysis were performed. The 10,100 insertions genomic reporter library resulted isolation 61 displaying differential...
The lipopeptidophosphoglycan of epimastigote forms Trypanosoma cruzi is composed a glycan linked through non-N-acetylated glucosamine residue to an inositol phosphorylceramide. Using conventional analysis techniques, including 1H, 13C, and 31P NMR spectroscopy negative ion fast atom bombardment mass spectroscopy, the structure carbohydrate-containing part molecule determined as: (Sequence: see text). There uncertainty as which 2-O-substituted alpha-D-Manp unit attached side chain or whether...
We have investigated the structure of glycosylphosphatidylinositol (GPI) anchor and O-linked glycan chains 40/45-kDa glycoprotein from cell surface protozoan parasite Trypanosoma cruzi. This glycoconjugate is major acceptor for sialic acid transferred by trans-sialidase T. cruzi Y-strain, epimastigote form. The GPI was liberated treatment with hot alkali, phosphoinositol-oligosaccharide moiety characterized shown to following structure. AEP | Man α(1−2) α(1−6) α(1−4) GleN α(1− 6)...
The effects of capsular polysaccharides, galactoxylomannan (GalXM) and glucuronoxylomannan (GXM), from acapsular (GXM negative) encapsulate strains Cryptococcus neoformans were investigated in RAW 264.7 peritoneal macrophages. Here, we demonstrate that GalXM GXM induced different cytokines profiles production TNF-α, NO iNOS expression, while predominantly TGF-β secretion. Both early morphological changes identified as autophagy late macrophages apoptosis mediated by Fas/FasL interaction, a...
We have recently described the application of a purified glycoprotein 25,000 Mr (GP25) Trypanosoma cruzi in serodiagnosis Chagas' disease. Purified GP25 lacks appreciable immunogenicity some animal species, spite being generally antigenic to parasitized hosts. The underlying cause for these contrasting observations has not been determined, but it may relate drastic extraction conditions used original isolation procedure, and possible damage inflicted native form this antigen. This report...
In this report we describe studies on the structures of O-linked carbohydrate units in cell-surface glycoproteins epimastigote forms G-strain Trypanosoma cruzi. Mild alkaline reductive degradation 38/43 kDa resulted beta-elimination glycosylated threonine and/or serine residues, and liberation N-acetylglucosaminitol, galactobiosyl-, galactotriosyl-, galactotetraosyl- galactopentaosyl-N-acetylglucosaminitol. The these oligosaccharide alditols were established by n.m.r. spectroscopy...
Burkholderia kururiensis is a diazotrophic bacterium originally isolated from polluted aquifer environment and presents high level of similarity with the rice endophyte "B. brasilensis" species. This work assessed ability B. to endophytically colonize plantlets by monitoring different tissues root-inoculated plants for presence bacterial growth in media, electron microscopy 16S rDNA analysis. Observations roots, stems leaves inoculated revealed colonization predominantly on root hair zones,...
Multidrug resistance (MDR) in cancer arises from cross-resistance to structurally- and functionally-divergent chemotherapeutic drugs. In particular, MDR is characterized by increased expression activity of ATP-binding cassette (ABC) superfamily transporters. Sphingolipids are substrates ABC proteins cell signaling, membrane biosynthesis, inflammation, for example, their products can favor progression. Glucosylceramide (GlcCer) a ubiquitous glycosphingolipid (GSL) generated glucosylceramide...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTChemical structure and antigenic aspects of complexes obtained from epimastigotes Trypanosoma cruziLucia Mendonca-Previato, Philip A. J. Gorin, Arnaldo F. Braga, Julio Scharfstein, Jose O. PreviatoCite this: Biochemistry 1983, 22, 21, 4980–4987Publication Date (Print):October 11, 1983Publication History Published online1 May 2002Published inissue 11 October...
A glycoprotein of 25,000 daltons (G25) purified from T. cruzi extracts is recognized by serum antibodies Chagas' disease patients. These human were isolated affinity chromatography and used to demonstrate that G25 antigenic determinants are i) represented at the parasite surface, ii) expressed in all developmental stages parasite's life cycle, as well several strains. This antigen-antibody system may be useful for diagnosis because radiolabeled found 96.5% 173 chagasic patients different...
Leishmania donovani, the agent of human visceral leishmaniasis, is an intracellular parasite that must be recognized and internalized by host macrophages to complete its biological cycle. In a search for possible ligands macrophage surface receptors, glycoconjugates were obtained from promastigotes aqueous, phenol-aqueous, alkaline extraction. A fucose-mannose glycoproteic ligand, lipopeptidephosphoglycan, phosphate mannogalactan ligand purified analyzed their chemical contents, with special...
Trypsin digestion of Hansenula wingei 21-cells releases a protein (21-factor-T) that inhibits the agglutination by purified 5-agglutinin obtained from 5-cells subtilisin [Crandall, M. A. & Brock, T. D. (1968) Bacteriol. Rev. 32, 139-163]. We have this inhibitor 415-fold ion-exchange chromatography, affinity adsorption to 5-cells, and gel permeation chromatography. The material shows diffuse band, on polyacrylamide electrophoresis in presence sodium dodecyl sulfate, with an apparent M r...
The genus Burkholderia includes over 60 species isolated from a wide range of environmental niches and can be tentatively divided into two major clusters. first cluster pathogens such as glumae, B. pseudomallei, mallei 17 well-studied the cepacia complex. other recently established comprises at least 29 nonpathogenic species, which in most cases have been found to associated with plants. It was previously that kururiensis, member latter cluster, possesses an N-acyl homoserine lactone (AHL)...
Upon activation, cytotoxic CD8(+) T lymphocytes are desialylated exposing beta-galactose residues in a physiological change that enhances their effector activity and can be monitored on the basis of increased binding lectin peanut agglutinin. Herein, we investigated impact sialylation mediated by trans-sialidase, specific unique Trypanosoma transglycosylase for sialic acid, cell response mice infected with T. cruzi. Our data demonstrate cruzi uses its trans-sialidase enzyme to resialylate...
The work reported herein describes the synthesis and assessment of trypanocidal activity thirteen new 1,2,4-triazole-3-thiones obtained from natural piperine, main constituent dry fruits Piper nigrum. It is part a research program aiming to use abundant easily available products as starting materials for design molecules potentially useful antiparasitic drugs. variously substituted triazole derivatives were synthesized amide in four steps with microwave irradiation on overall yields ranging...
Cryptococcus neoformans is a lethal fungus that primarily affects the respiratory system and central nervous system. One of main virulence factors capsule, constituted by polysaccharides glucuronoxylomannan (GXM) glucuronoxylomanogalactan (GXMGal). Polysaccharides are immunomodulators. target cell populations for modulation macrophages, which part first line defense important innate adaptive immunity. It has been reported macrophages can be modulated to act as “Trojan horse,” taking...
Abstract Cryptococcus gattii is a saprophytic basidiomycete that grows in the environment and can cause systemic cryptococcosis. Ocular cryptococcosis causes blindness commonly associated with central nervous system (CNS) infection. Toll-like receptor 9 (TLR9) control another mycosis. Here, using C57BL/6 TLR9 knockout mice (TLR9-/-), we evaluated role of signaling ocular involvement during C. gattii-infection. We observed impairment found high fungal burden retina, vitreous humor (VH), optic...