Trypanosoma rangeli

In this study, we performed the molecular and biochemical characterization of an ecto-enzyme present in Trypanosoma rangeli that is involved with the hydrolysis of extracellular inorganic pyrophosphate. PCR analysis identified a putative proton-pyrophosphatase (H(+)-PPase) in the epimastigote forms of T. rangeli. This protein was recognized with Western blot and flow cytometry analysis using an antibody against the H(+)-PPase of Arabidopsis thaliana. Immunofluorescence microscopy confirmed that this protein is located in the plasma membrane of T. rangeli. Biochemical assays revealed that the optimum pH for the ecto-PPase activity was 7.5, as previously demonstrated for other organisms. Sodium fluoride (NaF) and aminomethylenediphosphonate (AMDP) were able to inhibit approximately 75% and 90% of the ecto-PPase activity, respectively. This ecto-PPase activity was stimulated in a dose-dependent manner by MgCl2. In the presence of MgCl2, this activity was inhibited by millimolar concent...

Glycoconjugates play essential roles in cell recognition, infectivity and survival of protozoan parasites within their insect vectors and mammalian hosts. B-galactofuranose is a component of several glycoconjugates in many organisms, including a variety of trypanosomatids, but is absent in mammalian and African trypanosomes. Herein, we describe the presence of a b(1–3) galactofuranosyl transferase (GALFT), an important enzyme of the galactofuranose biosynthetic pathway, in Trypanosoma rangeli. The T. rangeli GALFT gene (TrGALFT) has an ORF of 1.2 Kb and is organized in two copies in the T. rangeli genome. Antibodies raised against an internal fragment of the transferase demonstrated a 45 kDa protein coded by TrGALFT was localized in the whole cytoplasm, mainly in the Golgi apparatus and equally expressed in epimastigotes and trypomastigotes from T. rangeli. Despite the high sequence similarity with Trypanosoma cruzi and Leishmania spp. orthologous TrGALFT showed a substitution of the metal-binding DXD motif, conserved amongst glycosyltransferases, for a DXE functionally analogous motif. Moreover, a reduced number of GALFT genes were present in T. rangeli when compared with other pathogenic kinetoplastid species.

A sylvatic infection focus of Trypanosoma rangeli, whose cycle involves the anteater Tamandua tetradactyla and triatomine insect Rhodnius robustus was observed in a pasture-dominated landscape of the rural riparian community of Sa ̃o Tome ́ located along the Tapajo ́s river in the municipal district of Aveiro (State of Para ́, Brazil), the Brazilian Amazon region. During a field work campaign with the objective of Chagas disease diagnosis in the Tapajo ́ s region, an anteater and 31 triatomines were found inhabiting in the same Attalea phalerata palm tree crown. Collected triatomines were identified as R. robustus with morphological and molecular procedures. The analysis of infection by T. rangeli using the repetitive ARN nucleolar Cl1 (sno-RNA-Cl1) gene showed that 25 triatomines of all stages were infected by T. rangeli (total infection rate of 80.6%). Infection by Trypanosoma cruzi using mini-exon markers was not identified. Examination of the digestive content of the triatomines demonstrated that the only feeding source found was the anteater. These results demonstrate that T. tetradactyla can be an important reservoir for T. rangeli and a good vehicle of the parasite within the Brazilian Amazon region.

SUMMARYTrypanosoma cruzi, causative agent of Chagas disease, co-infects its triatomine vector with its sister speciesTrypanosoma rangeli, which shares 60% of its antigens withT. cruzi. Additionally,T. rangelihas been observed to be pathogenic in some of its vector species. AlthoughT. cruzi–T. rangelico-infections are common, their effect on the vector has rarely been investigated. Therefore, we measured the fitness (survival and reproduction) of triatomine speciesRhodnius prolixusinfected with justT. cruzi, justT. rangeli, or bothT. cruziandT. rangeli. We found that survival (as estimated by survival probability and hazard ratios) was significantly different between treatments, with theT. cruzitreatment group having lower survival than the co-infected treatment. Reproduction and total fitness estimates in theT. cruziandT. rangelitreatments were significantly lower than in the co-infected and control groups. TheT. cruziandT. rangelitreatment group fitness estimates were not significa...

Trypanosoma cruzi, a human protozoan parasite, is the causative agent of Chagas disease. Currently the species is divided into six taxonomic groups. The genome of the CL Brener clone has been estimated to be 106.4-110.7 Mb, and DNA content analyses revealed that it is a diploid hybrid clone. Trypanosoma rangeli is a hemoflagellate that has the same reservoirs and vectors as T. cruzi; however, it is non-pathogenic to vertebrate hosts. The haploid genome of T. rangeli was previously estimated to be 24 Mb. The parasitic strains of T. rangeli are divided into KP1(+) and KP1(-). Thus, the objective of this study was to investigate the DNA content in different strains of T. cruzi and T. rangeli by flow cytometry. All T. cruzi and T. rangeli strains yielded cell cycle profiles with clearly identifiable G1-0 (2n) and G2-M (4n) peaks. T. cruzi and T. rangeli genome sizes were estimated using the clone CL Brener and the Leishmania major CC1 as reference cell lines because their genome sequenc...

This work shows that 3% (v/v) human urine (HU) in semisolid Liver Infusion Tryptose (SSL) medium favors the growth of Trypanosoma cruzi and T. rangeli. Parasites were plated as individual or mixed strains on SSL medium and on SSL medium with 3% human urine (SSL-HU). Isolate DNA was analyzed using polymerase chain reaction (PCR) and pulsed-field gel electrophoresis (PFGE). SSL-HU medium improved clone isolation. PCR revealed that T. cruzi strains predominate on mixed-strain plates. PFGE confirmed that isolated parasites share the same molecular karyotype as parental cell lines. SSL-HU medium constitutes a novel tool for obtaining T. cruzi and T. rangeli clonal lineages.

Cysteine metabolism is considered essential for the crucial maintenance of a reducing environment in trypanosomatids due to its importance as a precursor of trypanothione biosynthesis. Expression, activity, functional rescue, and overexpression of cysteine synthase (CS) and cystathionine β-synthase (CβS) were evaluated inLeishmania braziliensispromastigotes and intracellular amastigotes underin vitrostress conditions induced by hydrogen peroxide (H2O2),S-nitroso-N-acetylpenicillamine, or antimonial compounds. Our results demonstrate a stage-specific increase in the levels of protein expression and activity ofL. braziliensisCS (LbrCS) andL. braziliensisCβS (LbrCβS), resulting in an increment of total thiol levels in response to both oxidative and nitrosative stress. The rescue of the CS activity inTrypanosoma rangeli, a trypanosome that does not perform cysteine biosynthesisde novo, resulted in increased rates of survival of epimastigotes expressing the LbrCS under stress conditions ...

Spliced leader intergenic region (SL-IR) sequences from 23 Trypanosoma rangeli strains isolated from the salivary glands of Rhodnius colombiensis, R. ecuadoriensis, R. pallescens and R. prolixus and two human strains revealed the existence of 4 genotypes with CA, GT, TA, ATT and GTAT microsatellite repeats and the presence of insertions/deletions (INDEL) and single nucleotide polymorphism (SNP) characterizing each genotype. The strains isolated from the same vector species or the same Rhodnius evolutionary line presented the same genotypes, even in cases where strains had been isolated from vectors captured in geographically distant regions. The dendrogram constructed from the SL-IR sequences separated all of them into two main groups, one with the genotypes isolated from R. prolixus and the other group containing three well defined sub-groups with the genotypes isolated from R. pallescens, R. colombiensis and R. ecuadoriensis. Random amplified polymorphic DNA (RAPD) analysis showed the same two main groups and sub-groups supporting strict T. rangeli genotypes’ association with Rhodnius species. Combined with other studies, these results suggest a possible co-evolutionary association between T. rangeli genotypes and their vectors.Dendrograms constructed from the SL-IR sequences and RAPD showed the same topology suggesting a degree of co-evolution between the Trypanosoma rangeli genotypes and its vectors.► Strains of T. rangeli isolated from the same vector species presented the same genotypes. ► Association between the T. rangeli genotypes and its vectors was observed. ► Dendrograms from the SL-IR sequences and RAPD showed the same topology.

Assessment of the genetic variability and population structure of Trypanosoma rangeli, a non-pathogenic American trypanosome, was carried out through microsatellite and single-nucleotide polymorphism analyses. Two approaches were used for microsatellite typing: data mining in expressed sequence tag /open reading frame expressed sequence tags libraries and PCR-based Isolation of Microsatellite Arrays from genomic libraries. All microsatellites found were evaluated for their abundance, frequency and usefulness as markers. Genotyping of T. rangeli strains and clones was performed for 18 loci amplified by PCR from expressed sequence tag/open reading frame expressed sequence tags libraries. The presence of single-nucleotide polymorphisms in the nuclear, multi-copy, spliced leader gene was assessed in 18 T. rangeli strains, and the results show that T. rangeli has a predominantly clonal population structure, allowing a robust phylogenetic analysis. Microsatellite typing revealed a subdivi...