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1.
Parasit Vectors ; 12(1): 225, 2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31088523

RESUMO

BACKGROUND: The genus Trypanosoma Gruby, 1843 is constituted by terrestrial and aquatic phylogenetic lineages both harboring understudied trypanosomes from reptiles including an increasing diversity of crocodilian trypanosomes. Trypanosoma clandestinus Teixeira & Camargo, 2016 of the aquatic lineage is transmitted by leeches to caimans. Trypanosoma grayi Novy, 1906 of the terrestrial lineage is transmitted by tsetse flies to crocodiles in Africa, but the vectors of Neotropical caiman trypanosomes nested in this lineage remain unknown. RESULTS: Our phylogenetic analyses uncovered crocodilian trypanosomes in tabanids from South America and Africa, and trypanosomes other than T. grayi in tsetse flies. All trypanosomes found in tabanids clustered in the crocodilian clade (terrestrial lineage) forming six clades: Grayi (African trypanosomes from crocodiles and tsetse flies); Ralphi (trypanosomes from caimans, African and Brazilian tabanids and tsetse flies); Terena (caimans); Cay03 (caimans and Brazilian tabanids); and two new clades, Tab01 (Brazilian tabanid and tsetse flies) and Kaiowa. The clade Kaiowa comprises Trypanosoma kaiowa n. sp. and trypanosomes from African and Brazilian tabanids, caimans, tsetse flies and the African dwarf crocodile. Trypanosoma kaiowa n. sp. heavily colonises tabanid guts and differs remarkably in morphology from other caiman trypanosomes. This species multiplied predominantly as promastigotes on log-phase cultures showing scarce epimastigotes and exhibited very long flagellates in old cultures. Analyses of growth behavior revealed that insect cells allow the intracellular development of Trypanosoma kaiowa n. sp. CONCLUSIONS: Prior to this description of Trypanosoma kaiowa n. sp., no crocodilian trypanosome parasitic in tabanid flies had been cultured, morphologically examined by light, scanning and transmission microscopy, and phylogenetically compared with other crocodilian trypanosomes. Additionally, trypanosomes thought to be restricted to caimans were identified in Brazilian and African tabanids, tsetse flies and the dwarf crocodile. Similar repertoires of trypanosomes found in South American caimans, African crocodiles and tabanids from both continents support the recent diversification of these transcontinental trypanosomes. Our findings are consistent with trypanosome host-switching likely mediated by tabanid flies between caimans and transoceanic migrant crocodiles co-inhabiting South American wetlands at the Miocene.


Assuntos
Jacarés e Crocodilos/parasitologia , Dípteros/parasitologia , Trypanosoma/genética , Trypanosoma/isolamento & purificação , África , Animais , Brasil , DNA de Protozoário/genética , DNA Ribossômico/genética , Feminino , Insetos Vetores/parasitologia , Filogenia , RNA Ribossômico 18S/genética , Análise de Sequência de DNA , Moscas Tsé-Tsé/parasitologia
2.
Parasit. vectors. ; 12: 225, 2019.
Artigo | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib16000

RESUMO

Background The genus Trypanosoma Gruby, 1843 is constituted by terrestrial and aquatic phylogenetic lineages both harboring understudied trypanosomes from reptiles including an increasing diversity of crocodilian trypanosomes. Trypanosoma clandestinus Teixeira & Camargo, 2016 of the aquatic lineage is transmitted by leeches to caimans. Trypanosoma grayi Novy, 1906 of the terrestrial lineage is transmitted by tsetse flies to crocodiles in Africa, but the vectors of Neotropical caiman trypanosomes nested in this lineage remain unknown. Results Our phylogenetic analyses uncovered crocodilian trypanosomes in tabanids from South America and Africa, and trypanosomes other than T. grayi in tsetse flies. All trypanosomes found in tabanids clustered in the crocodilian clade (terrestrial lineage) forming six clades: Grayi (African trypanosomes from crocodiles and tsetse flies); Ralphi (trypanosomes from caimans, African and Brazilian tabanids and tsetse flies); Terena (caimans); Cay03 (caimans and Brazilian tabanids); and two new clades, Tab01 (Brazilian tabanid and tsetse flies) and Kaiowa. The clade Kaiowa comprises Trypanosoma kaiowa n. sp. and trypanosomes from African and Brazilian tabanids, caimans, tsetse flies and the African dwarf crocodile. Trypanosoma kaiowa n. sp. heavily colonises tabanid guts and differs remarkably in morphology from other caiman trypanosomes. This species multiplied predominantly as promastigotes on log-phase cultures showing scarce epimastigotes and exhibited very long flagellates in old cultures. Analyses of growth behavior revealed that insect cells allow the intracellular development of Trypanosoma kaiowa n. sp. Conclusions Prior to this description of Trypanosoma kaiowa n. sp., no crocodilian trypanosome parasitic in tabanid flies had been cultured, morphologically examined by light, scanning and transmission microscopy, and phylogenetically compared with other crocodilian trypanosomes. Additionally, trypanosomes thought to be restricted to caimans were identified in Brazilian and African tabanids, tsetse flies and the dwarf crocodile. Similar repertoires of trypanosomes found in South American caimans, African crocodiles and tabanids from both continents support the recent diversification of these transcontinental trypanosomes. Our findings are consistent with trypanosome host-switching likely mediated by tabanid flies between caimans and transoceanic migrant crocodiles co-inhabiting South American wetlands at the Miocene.

3.
Front Microbiol ; 9: 131, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29467742

RESUMO

This study is about the inter- and intra-specific genetic diversity of trypanosomatids of the genus Angomonas, and their association with Calliphoridae (blowflies) in Neotropical and Afrotropical regions. Microscopic examination of 3,900 flies of various families, mostly Calliphoridae, revealed that 31% of them harbored trypanosomatids. Small subunit rRNA (SSU rRNA) barcoding showed that Angomonas predominated (46%) over the other common trypanosomatids of blowflies of genera Herpetomonas and Wallacemonas. Among Angomonas spp., A. deanei was much more common than the two-other species, A. desouzai and A. ambiguus. Phylogenetic analyses based on SSU rRNA, glycosomal glyceraldehyde-3-phosphate dehydrogenase (gGAPDH) and internal transcribed spacer rDNA (ITS rDNA) sequences revealed a marked genetic diversity within A. deanei, which comprised four infraspecific genotypes (Dea1-Dea4), and four corresponding symbiont genotypes (Kcr1-Kcr4). Host and symbiont phylogenies were highly congruent corroborating their co-divergence, consistent with host-symbiont interdependent metabolism and symbiont reduced genomes shaped by a long coevolutionary history. We compared the diversity of Angomonas/symbionts from three genera of blowflies, Lucilia, Chrysomya and Cochliomyia. A. deanei, A. desouzai, and A. ambiguus were found in the three genera of blowflies in South America. In Africa, A. deanei and A. ambiguus were identified in Chrysomya. The absence of A. desouzai in Africa and its presence in Neotropical Cochliomyia and Lucilia suggests parasite spillback of A. desouzai into Chrysomya, which was most likely introduced four decades ago from Africa into the Neotropic. The absence of correlation between parasite diversity and geographic and genetic distances, with identical genotypes of A. deanei found in the Neotropic and Afrotropic, is consistent with disjunct distribution due to the recent human-mediated transoceanic dispersal of Angomonas by Chrysomya. This study provides the most comprehensive data gathered so far on the genetic repertoires of a genus of trypanosomatids found in flies from a wide geographical range.

4.
Infect Genet Evol ; 63: 380-390, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-28882517

RESUMO

Trypanosoma (Herpetosoma) lewisi is a cosmopolitan parasite of rodents strongly linked to the human dispersal of Rattus spp. from Asia to the rest of the world. This species is highly phylogenetically related to trypanosomes from other rodents (T. lewisi-like), and sporadically infects other mammals. T. lewisi may opportunistically infect humans, and has been considered an emergent rat-borne zoonosis associated to poverty. We developed the THeCATL-PCR based on Cathepsin L (CATL) sequences to specifically detect T. (Herpetosoma) spp., and assess their genetic diversity. This method exhibited high sensitivity using blood samples, and is the first molecular method employed to search for T. lewisi in its flea vectors. THeCATL-PCR surveys using simple DNA preparation from blood preserved in ethanol or filter paper detected T. lewisi in Rattus spp. from human dwellings in South America (Brazil and Venezuela), East Africa (Mozambique), and Southeast Asia (Thailand, Cambodia and Lao PDR). In addition, native rodents captured in anthropogenic and nearby human settlements in natural habitats harbored T. (Herpetosoma) spp. PCR-amplified CATL gene fragments (253bp) distinguish T. lewisi and T. lewisi-like from other trypanosomes, and allow for assessment of genetic diversity and relationships among T. (Herpetosoma) spp. Our molecular surveys corroborated worldwide high prevalence of T. lewisi, incriminating Mastomys natalensis as an important carrier of this species in Africa, and supported its spillover from invader Rattus spp. to native rodents in Brazil and Mozambique. THeCATL-PCR provided new insights on the accurate diagnosis and genetic repertoire of T. (Herpetosoma) spp. in rodent and non-rodent hosts, revealing a novel species of this subgenus in an African gerbil. Phylogenetic analysis based on CATL sequences from T. (Herpetosoma) spp. and other trypanosomes (amplified using pan-trypanosome primers) uncovered rodents harboring, beyond mammal trypanosomes of different subgenera, some species that clustered in the lizard-snake clade of trypanosomes.


Assuntos
Catepsina L/genética , Proteínas de Protozoários/genética , Doenças dos Roedores/epidemiologia , Trypanosoma lewisi/genética , Tripanossomíase/veterinária , Zoonoses/epidemiologia , Distribuição Animal , Animais , Brasil/epidemiologia , Camboja/epidemiologia , DNA de Protozoário/genética , Gerbillinae/parasitologia , Humanos , Laos/epidemiologia , Moçambique/epidemiologia , Murinae/parasitologia , Filogenia , Reação em Cadeia da Polimerase/métodos , Ratos , Doenças dos Roedores/parasitologia , Doenças dos Roedores/transmissão , Sifonápteros/parasitologia , Tailândia/epidemiologia , Trypanosoma lewisi/classificação , Trypanosoma lewisi/isolamento & purificação , Tripanossomíase/epidemiologia , Tripanossomíase/parasitologia , Tripanossomíase/transmissão , Zoonoses/parasitologia , Zoonoses/transmissão
5.
Eur J Protistol ; 56: 232-249, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27771468

RESUMO

The genus Phytomonas includes trypanosomatids transmitted to the fruits, latex, and phloem of vascular plants by hemipterans. We inferred the phylogenetic relationships of plant and insect isolates assigned to the previously defined genetic groups A-F and H of Phytomonas, particularly those from groups A, C and E comprising flagellates of Solanaceae fruits. Phylogenetic analyses using glycosomal Glyceraldehyde Phosphate Dehydrogenase (gGAPDH) and Small Subunit rRNA (SSU rRNA) genes strongly supported the monophyly of the genus Phytomonas and its division into seven main infrageneric phylogenetic lineages (Phy clades). Isolates from fruit or latex do not constitute monophyletic assemblages but disperse through more than one lineages. In this study, fruit flagellates were distributed in three clades: PhyA, formed by isolates from Solanaceae and phytophagous hemipterans; PhyC comprising flagellates from four plant families; and PhyE, which contains 15 fruit isolates from seven species of Solanaceae. The flagellates of PhyE are described as Phytomonas dolleti n. sp. according to their positioning in phylogenetic trees, complemented by data about their life cycle, and developmental and morphological characteristics in cultures, fruits of Solanum spp., and salivary glands of the vector, the phytophagous hemipteran Arvelius albopunctatus (Pentatomidae).


Assuntos
Euglenozoários/classificação , Hemípteros/parasitologia , Filogenia , Animais , Glândulas Salivares/parasitologia , Solanaceae/parasitologia , Especificidade da Espécie
6.
J Eukaryot Microbiol ; 63(5): 610-22, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26932133

RESUMO

We described the phylogenetic affiliation, development in cultures and ultrastructural features of a trypanosome of Leptodacylus chaquensis from the Pantanal biome of Brazil. In the inferred phylogeny, this trypanosome nested into the Anura clade of the basal Aquatic clade of Trypanosoma, but was separate from all known species within this clade. This finding enabled us to describe it as Trypanosoma herthameyeri n. sp., which also infects other Leptodacylus species from the Pantanal and Caatinga biomes. Trypanosoma herthameyeri multiplies as small rounded forms clumped together and evolving into multiple-fission forms and rosettes of epimastigotes released as long forms with long flagella; scarce trypomastigotes and glove-like forms are common in stationary-phase cultures. For the first time, a trypanosome from an amphibian was observed by field emission scanning electron microscopy, revealing a cytostome opening, well-developed flagellar lamella, and many grooves in pumpkin-like forms. Transmission electron microscopy showed highly developed Golgi complexes, relaxed catenation of KDNA, and a rich set of spongiome tubules in a regular parallel arrangement to the flagellar pocket as confirmed by electron tomography. Considering the basal position in the phylogenetic tree, developmental and ultrastructural data of T. herthameyeri are valuable for evolutionary studies of trypanosome architecture and cell biology.


Assuntos
Anuros/parasitologia , Filogenia , Trypanosoma/classificação , Trypanosoma/ultraestrutura , Tripanossomíase/veterinária , Animais , Anuros/sangue , Biodiversidade , Brasil , Classificação , DNA de Protozoário/genética , Ecologia , Ecossistema , Tomografia com Microscopia Eletrônica/métodos , Flagelos/ultraestrutura , Complexo de Golgi/ultraestrutura , Especificidade de Hospedeiro , Microscopia Eletrônica de Varredura/métodos , Microscopia Eletrônica de Transmissão/métodos , Trypanosoma/crescimento & desenvolvimento , Trypanosoma/isolamento & purificação , Tripanossomíase/sangue , Tripanossomíase/diagnóstico , Tripanossomíase/parasitologia
7.
Parasit Vectors ; 8: 657, 2015 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-26701154

RESUMO

BACKGROUND: Bat trypanosomes are implicated in the evolution of the T. cruzi clade, which harbours most African, European and American trypanosomes from bats and other trypanosomes from African, Australian and American terrestrial mammals, including T. cruzi and T. rangeli, the agents of the American human trypanosomiasis. The diversity of bat trypanosomes globally is still poorly understood, and the common ancestor, geographical origin, and evolution of species within the T. cruzi clade remain largely unresolved. METHODS: Trypanosome sequences were obtained from cultured parasites and from museum archived liver/blood samples of bats captured from Guatemala (Central America) to the Brazilian Atlantic Coast. Phylogenies were inferred using Small Subunit (SSU) rRNA, glycosomal glyceraldehyde phosphate dehydrogenase (gGAPDH), and Spliced Leader (SL) RNA genes. RESULTS: Here, we described Trypanosoma wauwau n. sp. from Pteronotus bats (Mormoopidae) placed in the T. cruzi clade, then supporting the bat-seeding hypothesis whereby the common ancestor of this clade likely was a bat trypanosome. T. wauwau was sister to the clade T. spp-Neobats from phyllostomid bats forming an assemblage of trypanosome species exclusively of Noctilionoidea Neotropical bats, which was sister to an Australian clade of trypanosomes from indigenous marsupials and rodents, which possibly evolved from a bat trypanosome. T. wauwau was found in 26.5% of the Pteronotus bats examined, and phylogeographical analysis evidenced the wide geographical range of this species. To date, this species was not detected in other bats, including those that were sympatric or shared shelters with Pteronotus. T. wauwau did not develop within mammalian cells, and was not infective to Balb/c mice or to triatomine vectors of T. cruzi and T. rangeli. CONCLUSIONS: Trypanosoma wauwau n. sp. was linked to Pteronotus bats. The positioning of the clade T. wauwau/T.spp-Neobats as the most basal Neotropical bat trypanosomes and closely related to an Australian lineage of trypanosomes provides additional evidence that the T. cruzi clade trypanosomes likely evolved from bats, and were dispersed in bats within and between continents from ancient to unexpectedly recent times.


Assuntos
Evolução Molecular , Variação Genética , Trypanosoma cruzi/classificação , Trypanosoma cruzi/genética , Animais , Austrália , Brasil , América Central , Quirópteros , Análise por Conglomerados , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/genética , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 18S/genética , RNA Líder para Processamento , Análise de Sequência de DNA , Homologia de Sequência , Trypanosoma cruzi/isolamento & purificação
8.
Int J Parasitol Parasites Wildl ; 4(3): 368-78, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26767165

RESUMO

Trypanosoma terena and Trypanosoma ralphi are known species of the South American crocodilians Caiman crocodilus, Caiman yacare and Melanosuchus niger and are phylogenetically related to the tsetse-transmitted Trypanosoma grayi of the African Crocodylus niloticus. These trypanosomes form the Crocodilian clade of the terrestrial clade of the genus Trypanosoma. A PCR-survey for trypanosomes in caiman blood samples and in leeches taken from caimans revealed unknown trypanosome diversity and frequent mixed infections. Phylogenies based on SSU (small subunit) of rRNA and gGAPDH (glycosomal Glyceraldehyde Phosphate Dehydrogenase) gene sequences revealed a new trypanosome species clustering with T. terena and T. ralphi in the crocodilian clade and an additional new species nesting in the distant Aquatic clade of trypanosomes, which is herein named Trypanosoma clandestinus n. sp. This new species was found in Caiman yacare, Caiman crocodilus and M. niger from the Pantanal and Amazonian biomes in Brazil. Large numbers of dividing epimastigotes and unique thin and long trypomastigotes were found in the guts of leeches (Haementeria sp.) removed from the mouths of caimans. The trypanosomes recovered from the leeches had sequences identical to those of T. clandestinus of caiman blood samples. Experimental infestation of young caimans (Caiman yacare) with infected leeches resulted in long-lasting T. clandestinus infections that permitted us to delineate its life cycle. In contrast to T. terena, T. ralphi and T. grayi, which are detectable by hemoculturing, microscopy and standard PCR of caiman blood, T. clandestinus passes undetected by these methods due to very low parasitemia and could be detected solely by the more sensitive nested PCR method. T. clandestinus n. sp. is the first crocodilian trypanosome known to be transmitted by leeches and positioned in the aquatic clade closest to fish trypanosomes. Our data show that caimans can host trypanosomes of the aquatic or terrestrial clade, sometimes simultaneously.

9.
Rev Soc Bras Med Trop ; 47(3): 374-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24728471

RESUMO

INTRODUCTION: This study reports for the first time the infection of Rhodnius montenegrensis by Trypanosoma rangeli. METHODS: The triatomines were manually collected in Attalea speciosa in the municipality of Buritis, Rondônia. The identification of the trypanosomatid species was confirmed by multiplex PCR. RESULTS: All of the collected triatomines were R. montenegrensis. The analysis confirmed that all of the adults were infected with the epimastigote form of T. rangeli. CONCLUSIONS: This report of a new vector of T. rangeli raises a warning for the State of Rondônia because the simultaneous presence of T. rangeli with T. cruzi in the same geographic region enables the occurrence of mixed infections in hosts and vectors, which complicates the differential diagnosis.


Assuntos
DNA de Protozoário/genética , Insetos Vetores/parasitologia , Rhodnius/parasitologia , Trypanosoma rangeli/isolamento & purificação , Animais , Reação em Cadeia da Polimerase Multiplex , Trypanosoma rangeli/genética
10.
Parasit Vectors ; 6(1): 221, 2013 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-23915781

RESUMO

BACKGROUND: Bat trypanosomes have been implicated in the evolutionary history of the T. cruzi clade, which comprises species from a wide geographic and host range in South America, Africa and Europe, including bat-restricted species and the generalist agents of human American trypanosomosis T. cruzi and T. rangeli. METHODS: Trypanosomes from bats (Rhinolophus landeri and Hipposideros caffer) captured in Mozambique, southeast Africa, were isolated by hemoculture. Barcoding was carried out through the V7V8 region of Small Subunit (SSU) rRNA and Fluorescent Fragment Length barcoding (FFLB). Phylogenetic inferences were based on SSU rRNA, glyceraldehyde phosphate dehydrogenase (gGAPDH) and Spliced Leader (SL) genes. Morphological characterization included light, scanning and transmission electron microscopy. RESULTS: New trypanosomes from bats clustered together forming a clade basal to a larger assemblage called the T. cruzi clade. Barcoding, phylogenetic analyses and genetic distances based on SSU rRNA and gGAPDH supported these trypanosomes as a new species, which we named Trypanosoma livingstonei n. sp. The large and highly polymorphic SL gene repeats of this species showed a copy of the 5S ribosomal RNA into the intergenic region. Unique morphological (large and broad blood trypomastigotes compatible to species of the subgenus Megatrypanum and cultures showing highly pleomorphic epimastigotes and long and slender trypomastigotes) and ultrastructural (cytostome and reservosomes) features and growth behaviour (when co-cultivated with HeLa cells at 37°C differentiated into trypomastigotes resembling the blood forms and do not invaded the cells) complemented the description of this species. CONCLUSION: Phylogenetic inferences supported the hypothesis that Trypanosoma livingstonei n. sp. diverged from a common ancestral bat trypanosome that evolved exclusively in Chiroptera or switched at independent opportunities to mammals of several orders forming the clade T. cruzi, hence, providing further support for the bat seeding hypothesis to explain the origin of T. cruzi and T. rangeli.


Assuntos
Quirópteros/parasitologia , Reservatórios de Doenças/parasitologia , Trypanosoma cruzi/classificação , Trypanosoma cruzi/isolamento & purificação , Tripanossomíase/parasitologia , Animais , DNA de Protozoário/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Moçambique , Filogenia , Proteínas de Protozoários/genética , RNA Ribossômico/genética , Trypanosoma cruzi/genética , Trypanosoma cruzi/fisiologia
11.
Parasit Vectors ; 6(1): 313, 2013 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-24499634

RESUMO

BACKGROUND: Little is known about the diversity, phylogenetic relationships, and biogeography of trypanosomes infecting non-mammalian hosts. In this study, we investigated the influence of host species and biogeography on shaping the genetic diversity, phylogenetic relationship, and distribution of trypanosomes from South American alligatorids and African crocodilids. METHODS: Small Subunit rRNA (SSU rRNA) and glycosomal Glyceraldehyde Phosphate Dehydrogenase (gGAPDH) genes were employed for phylogenetic inferences. Trypanosomes from crocodilians were obtained by haemoculturing. Growth behaviour, morphology, and ultrastructural features complement the molecular description of two new species strongly supported by phylogenetic analyses. RESULTS: The inferred phylogenies disclosed a strongly supported crocodilian-restricted clade comprising three subclades. The subclade T. grayi comprised the African Trypanosoma grayi from Crocodylus niloticus and tsetse flies. The subclade T. ralphi comprised alligatorid trypanosomes represented by Trypanosoma ralphi n. sp. from Melanosuchus niger, Caiman crocodilus and Caiman yacare from Brazilian river basins. T. grayi and T. ralphi were sister subclades. The basal subclade T. terena comprised alligatorid trypanosomes represented by Trypanosoma terena n. sp. from Ca. yacare sharing hosts and basins with the distantly genetic related T. ralphi. This subclade also included the trypanosome from Ca. crocodilus from the Orinoco basin in Venezuela and, unexpectedly, a trypanosome from the African crocodilian Osteolaemus tetraspis. CONCLUSION: The close relationship between South American and African trypanosomes is consistent with paleontological evidence of recent transoceanic dispersal of Crocodylus at the Miocene/Pliocene boundaries (4-5 mya), and host-switching of trypanosomes throughout the geological configuration of South American hydrographical basins shaping the evolutionary histories of the crocodilians and their trypanosomes.


Assuntos
Jacarés e Crocodilos/parasitologia , Variação Genética , Filogeografia , Trypanosoma/classificação , Trypanosoma/isolamento & purificação , África , Animais , Análise por Conglomerados , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Genes de RNAr , Microscopia , Dados de Sequência Molecular , RNA de Protozoário/genética , RNA Ribossômico 18S/genética , Análise de Sequência de DNA , América do Sul , Trypanosoma/citologia , Trypanosoma/genética
12.
Protist ; 164(1): 129-52, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22938923

RESUMO

In order to review the taxonomy of the genus Herpetomonas through phylogenetic and morphological analyses we barcoded 527 insect trypanosomatids by sequencing the V7V8 region of the small subunit ribosomal RNA (SSU rRNA) gene. Fifty two flagellates, 90% of them from Diptera, revealed to be related to known species of Herpetomonas. Sequences of entire glycosomal glyceraldehyde phosphate dehydrogenase (gGAPDH) and SSU rRNA genes were employed for phylogenetic inferences including representatives of all genera of Trypanosomatidae. In the resulting phylogenetic trees, the selected flagellates clustered into a monophyletic assemblage that we are considering as the redefined genus Herpetomonas. Internal transcribed spacer 1 (ITS1) rDNA sequences and putative secondary structures of this region were compared for evaluation of inter- and intraspecific variability. The flagellates were classified in six already known species and five new species. In addition, two Leptomonas spp. were moved to Herpetomonas, now comprising 13 valid species, while four species were excluded from the genus. Light and electron microscopy revealed the extreme polymorphism of Herpetomonas, hindering genus and species identification by morphological characteristics. Our findings also showed that some species of Herpetomonas are generalist parasites of flies and appear to be as cosmopolitan as their hosts.


Assuntos
Dípteros/parasitologia , Trypanosomatina/classificação , Trypanosomatina/genética , Animais , Análise por Conglomerados , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Genes de RNAr , Gliceraldeído-3-Fosfato Desidrogenases/genética , Microscopia , Modelos Moleculares , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Filogenia , RNA de Protozoário/genética , RNA Ribossômico 18S/genética , Análise de Sequência de DNA , Trypanosomatina/citologia , Trypanosomatina/isolamento & purificação
13.
Protist ; 163(6): 856-72, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22277804

RESUMO

Parasites of the genus Trypanosoma are common in bats and those of the subgenus Schizotrypanum are restricted to bats throughout the world, with the exception of Trypanosoma (Schizotrypanum) cruzi that also infects other mammals and is restricted to the American Continent. We have characterized trypanosome isolates from Molossidae bats captured in Mozambique, Africa. Morphology and behaviour in culture, supported by phylogenetic inferences using SSU (small subunit) rRNA, gGAPDH (glycosomal glyceraldehyde 3-phosphate dehydrogenase) and Cyt b (cytochrome b) genes, allowed to classify the isolates as a new Schizotrypanum species named Trypanosoma (Schizotrypanum) erneyi sp. nov. This is the first report of a Schizotrypanum species from African bats cultured, characterized morphologically and biologically, and positioned in phylogenetic trees. The unprecedented finding of a new species of the subgenus Schizotrypanum from Africa that is closest related to the America-restricted Trypanosoma (Schizotrypanum) cruzi marinkellei and T. cruzi provides new insights into the origin and evolutionary history of T. cruzi and closely related bat trypanosomes. Altogether, data from our study support the hypothesis of an ancestor trypanosome parasite of bats evolving to infect other mammals, even humans, and adapted to transmission by triatomine bugs in the evolutionary history of T. cruzi in the New World.


Assuntos
Quirópteros/parasitologia , Trypanosoma/classificação , Trypanosoma/isolamento & purificação , Tripanossomíase/veterinária , Animais , Análise por Conglomerados , Citocromos b/genética , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Genes de RNAr , Gliceraldeído 3-Fosfato Desidrogenase (NADP+)/genética , Dados de Sequência Molecular , Moçambique , Filogenia , RNA de Protozoário/genética , RNA Ribossômico 18S/genética , Análise de Sequência de DNA , Trypanosoma/citologia , Trypanosoma/genética , Tripanossomíase/parasitologia
14.
Int J Parasitol ; 41(13-14): 1385-96, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22051399

RESUMO

Species of the subgenus Trypanosoma (Megatrypanum) have been reported in cattle and other domestic and wild ruminants worldwide. A previous study in Brazil found at least four genotypes infecting cattle (Bos taurus), but only one in water buffalo (Bubalus bubalis). However, the small number of isolates examined from buffalo, all inhabiting nearby areas, has precluded evaluation of their diversity, host associations and geographical structure. To address these questions, we evaluated the genetic diversity and phylogeographical patterns of 25 isolates from water buffalo and 28 from cattle from four separate locations in Brazil and Venezuela. Multigene phylogenetic analyses of ssrRNA, internal transcribed spacer of rDNA (ITSrDNA), 5SrRNA, glycosomal glyceraldehyde 3-phosphate dehydrogenase (gGAPDH), mitochondrial cytochrome b (Cyt b), spliced leader (SL) and cathepsin L-like (CATL) sequences positioned all isolates from sympatric and allopatric buffalo populations into the highly homogeneous genotype TthIA, while the cattle isolates were assigned to three different genotypes, all distinct from TthIA. Polymorphisms in all of these sequences separated the trypanosomes infecting water buffalo, cattle, sheep, antelope and deer, and suggested that they correspond to separate species. Congruent phylogenies inferred with all genes indicated a predominant clonal structure of the genotypes. The multilocus analysis revealed one monophyletic assemblage formed exclusively by trypanosomes of ruminants, which corresponds to the subgenus T. (Megatrypanum). The high degree of host specificity, evidenced by genotypes exclusive to each ruminant species and lack of genotype shared by different host species, suggested that the evolutionary history of trypanosomes of this subgenus was strongly constrained by their ruminant hosts. However, incongruence between ruminant and trypanosome phylogenies did not support host-parasite co-evolution, indicating that host switches have occurred across ruminants followed by divergences, giving rise to new trypanosome genotypes adapted exclusively to one host species.


Assuntos
Evolução Biológica , Búfalos/parasitologia , Doenças dos Bovinos/parasitologia , Filogenia , Ruminantes/parasitologia , Trypanosoma/classificação , Trypanosoma/genética , Tripanossomíase/veterinária , Animais , Brasil , Bovinos , Genótipo , Especificidade de Hospedeiro , Dados de Sequência Molecular , Filogeografia , Trypanosoma/isolamento & purificação , Trypanosoma/fisiologia , Tripanossomíase/parasitologia , Venezuela
15.
Protist ; 162(3): 503-24, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21420905

RESUMO

We comparatively examined the nutritional, molecular and optical and electron microscopical characteristics of reference species and new isolates of trypanosomatids harboring bacterial endosymbionts. Sequencing of the V7V8 region of the small subunit of the ribosomal RNA (SSU rRNA) gene distinguished six major genotypes among the 13 isolates examined. The entire sequences of the SSU rRNA and glycosomal glyceraldehyde phosphate dehydrogenase (gGAPDH) genes were obtained for phylogenetic analyses. In the resulting phylogenetic trees, the symbiont-harboring species clustered as a major clade comprising two subclades that corresponded to the proposed genera Angomonas and Strigomonas. The genus Angomonas comprised 10 flagellates including former Crithidia deanei and C. desouzai plus a new species. The genus Strigomonas included former Crithidia oncopelti and Blastocrithidia culicis plus a new species. Sequences from the internal transcribed spacer of ribosomal DNA (ITS rDNA) and size polymorphism of kinetoplast DNA (kDNA) minicircles revealed considerable genetic heterogeneity within the genera Angomonas and Strigomonas. Phylogenetic analyses based on 16S rDNA and ITS rDNA sequences demonstrated that all of the endosymbionts belonged to the Betaproteobacteria and revealed three new species. The congruence of the phylogenetic trees of trypanosomatids and their symbionts support a co-divergent host-symbiont evolutionary history.


Assuntos
Betaproteobacteria/classificação , Betaproteobacteria/genética , Simbiose , Trypanosomatina/classificação , Trypanosomatina/genética , Sequência de Bases , Betaproteobacteria/isolamento & purificação , Betaproteobacteria/ultraestrutura , Evolução Biológica , Código de Barras de DNA Taxonômico/métodos , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Intergênico/química , DNA Intergênico/genética , DNA de Cinetoplasto/química , DNA de Cinetoplasto/genética , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Funções Verossimilhança , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Filogenia , Polimorfismo Genético , RNA Ribossômico 16S/genética , Subunidades Ribossômicas Menores/genética , Análise de Sequência de DNA , Simbiose/genética , Trypanosomatina/isolamento & purificação , Trypanosomatina/ultraestrutura
16.
Parasitol Int ; 59(3): 318-25, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20230907

RESUMO

Although Trypanosomatheileri and allied trypanosomes are the most widespread trypanosomes in bovids little is known about proteolytic enzymes in these species. We have characterized genes encoding for cathepsin L-like (CATL) cysteine proteases from isolates of cattle, water buffalo and deer that largely diverged from homologues of other trypanosome species. Analysis of 78 CATL catalytic domain sequences from 22 T. theileri trypanosomes disclosed 6 genotypes tightly clustered together into the T. theileri clade. The CATL genes in these trypanosomes are organized in tandem arrays of approximately 1.7kb located in 2 chromosomal bands of 600-720kb. A diagnostic PCR assay targeting CATL sequences detected T. theileri of all genotypes from cattle, buffaloes and cervids and also from tabanid vectors. Expression of T. theileri cysteine proteases was demonstrated by proteolytic activity in gelatin gels and hydrolysis of Z-Phe-Arg-AMC substrate. Results from this work agree with previous data using ribosomal and spliced leader genes demonstrating that CATL gene sequences are useful for diagnosis, population genotyping and evolutionary studies of T. theileri trypanosomes.


Assuntos
Catepsina L/genética , Doenças dos Bovinos/diagnóstico , Cisteína Proteases/genética , Gado/parasitologia , Trypanosoma/enzimologia , Tripanossomíase/veterinária , Sequência de Aminoácidos , Animais , Búfalos/parasitologia , Catepsina L/química , Catepsina L/metabolismo , Bovinos , Doenças dos Bovinos/parasitologia , Cisteína Proteases/química , Cisteína Proteases/metabolismo , DNA de Protozoário/análise , DNA de Protozoário/genética , Cervos/parasitologia , Genótipo , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Trypanosoma/classificação , Trypanosoma/genética , Tripanossomíase/diagnóstico , Tripanossomíase/parasitologia
17.
Int J Parasitol ; 40(3): 345-55, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-19766649

RESUMO

The genetic diversity and phylogeographical patterns of Trypanosoma species that infect Brazilian bats were evaluated by examining 1043 bats from 63 species of seven families captured in Amazonia, the Pantanal, Cerrado and the Atlantic Forest biomes of Brazil. The prevalence of trypanosome-infected bats, as estimated by haemoculture, was 12.9%, resulting in 77 cultures of isolates, most morphologically identified as Trypanosoma cf. cruzi, classified by barcoding using partial sequences from ssrRNA gene into the subgenus Schizotrypanum and identified as T. cruzi (15), T. cruzi marinkellei (37) or T. cf. dionisii (25). Phylogenetic analyses using nuclear ssrRNA, glycosomal glyceraldehyde 3-phosphate dehydrogenase (gGAPDH) and mitochondrial cytochrome b (Cyt b) gene sequences generated three clades, which clustered together forming the subgenus Schizotrypanum. In addition to vector association, bat trypanosomes were related by the evolutionary history, ecology and phylogeography of the bats. Trypanosoma cf. dionisii trypanosomes (32.4%) infected 12 species from four bat families captured in all biomes, from North to South Brazil, and clustered with T. dionisii from Europe despite being separated by some genetic distance. Trypanosoma cruzi marinkellei (49.3%) was restricted to phyllostomid bats from Amazonia to the Pantanal (North to Central). Trypanosoma cruzi (18.2%) was found mainly in vespertilionid and phyllostomid bats from the Pantanal/Cerrado and the Atlantic Forest (Central to Southeast), with a few isolates from Amazonia.


Assuntos
Quirópteros/parasitologia , Variação Genética , Trypanosoma/classificação , Trypanosoma/isolamento & purificação , Tripanossomíase/veterinária , Animais , Brasil , Análise por Conglomerados , Citocromos b/genética , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Genes de RNAr , Geografia , Gliceraldeído-3-Fosfato Desidrogenases/genética , Dados de Sequência Molecular , Filogenia , Proteínas de Protozoários/genética , RNA de Protozoário/genética , RNA Ribossômico 18S/genética , Análise de Sequência de DNA , Trypanosoma/genética , Tripanossomíase/parasitologia
18.
J Eukaryot Microbiol ; 56(6): 594-602, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19883449

RESUMO

We sequenced the small subunit (SSU) rRNA and glycosomal glyceraldehyde-3-phosphate dehydrogenase (gGAPDH) genes of two trypanosomes isolated from the Brazilian snakes Pseudoboa nigra and Crotalus durissus terrificus. Trypanosomes were cultured and their morphometrical and ultrastructural features were characterized by light microscopy and scanning and transmission electron microscopy. Phylogenetic trees inferred using independent or combined SSU rRNA and gGAPDH data sets always clustered the snake trypanosomes together in a clade closest to lizard trypanosomes, forming a strongly supported monophyletic assemblage (i.e. lizard-snake clade). The positioning in the phylogenetic trees and the barcoding based on the variable V7-V8 region of the SSU rRNA, which showed high sequence divergences, allowed us to classify the isolates from distinct snake species as separate species. The isolate from P. nigra is described as a new species, Trypanosoma serpentis n. sp., whereas the isolate from C. d. terrificus is redescribed here as Trypanosoma cascavelli.


Assuntos
DNA de Protozoário/classificação , Gliceraldeído-3-Fosfato Desidrogenases/genética , Filogenia , Subunidades Ribossômicas Menores/genética , Serpentes/parasitologia , Trypanosoma/classificação , Animais , Brasil , DNA de Protozoário/análise , DNA de Protozoário/genética , Interações Hospedeiro-Parasita , Lagartos/parasitologia , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , RNA Ribossômico/análise , RNA Ribossômico/classificação , RNA Ribossômico/genética , Análise de Sequência de DNA , Especificidade da Espécie , Trypanosoma/genética , Trypanosoma/ultraestrutura
19.
Infect Genet Evol ; 9(6): 1265-74, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19632356

RESUMO

We characterized 28 new isolates of Trypanosoma cruzi IIc (TCIIc) of mammals and triatomines from Northern to Southern Brazil, confirming the widespread distribution of this lineage. Phylogenetic analyses using cytochrome b and SSU rDNA sequences clearly separated TCIIc from TCIIa according to terrestrial and arboreal ecotopes of their preferential mammalian hosts and vectors. TCIIc was more closely related to TCIId/e, followed by TCIIa, and separated by large distances from TCIIb and TCI. Despite being indistinguishable by traditional genotyping and generally being assigned to Z3, we provide evidence that TCIIa from South America and TCIIa from North America correspond to independent lineages that circulate in distinct hosts and ecological niches. Armadillos, terrestrial didelphids and rodents, and domestic dogs were found infected by TCIIc in Brazil. We believe that, in Brazil, this is the first description of TCIIc from rodents and domestic dogs. Terrestrial triatomines of genera Panstrongylus and Triatoma were confirmed as vectors of TCIIc. Together, habitat, mammalian host and vector association corroborated the link between TCIIc and terrestrial transmission cycles/ecological niches. Analysis of ITS1 rDNA sequences disclosed clusters of TCIIc isolates in accordance with their geographic origin, independent of their host species.


Assuntos
Doença de Chagas/veterinária , Ecossistema , Geografia , Doenças Parasitárias em Animais/parasitologia , Filogenia , Trypanosoma cruzi/classificação , Animais , Tatus/parasitologia , Brasil , Doença de Chagas/parasitologia , Citocromos b/análise , Citocromos b/genética , DNA Espaçador Ribossômico/análise , DNA Espaçador Ribossômico/genética , Cães , Genoma de Protozoário , Interações Hospedeiro-Parasita , Humanos , Insetos Vetores/parasitologia , Gambás/parasitologia , Panstrongylus/parasitologia , Roedores/parasitologia , Especificidade da Espécie , Triatoma/parasitologia , Trypanosoma cruzi/genética , Trypanosoma cruzi/isolamento & purificação
20.
Int J Parasitol ; 39(5): 615-23, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19041313

RESUMO

In this study, we provide phylogenetic and biogeographic evidence that the Trypanosoma cruzi lineages T. cruzi I (TCI) and T. cruzi IIa (TCIIa) circulate amongst non-human primates in Brazilian Amazonia, and are transmitted by Rhodnius species in overlapping arboreal transmission cycles, sporadically infecting humans. TCI presented higher prevalence rates, and no lineages other than TCI and TCIIa were found in this study in wild monkeys and Rhodnius from the Amazonian region. We characterised TCI and TCIIa from wild primates (16 TCI and five TCIIa), Rhodnius spp. (13 TCI and nine TCIIa), and humans with Chagas disease associated with oral transmission (14 TCI and five TCIIa) in Brazilian Amazonia. To our knowledge, TCIIa had not been associated with wild monkeys until now. Polymorphisms of ssrDNA, cytochrome b gene sequences and randomly amplified polymorphic DNA (RAPD) patterns clearly separated TCIIa from TCIIb-e and TCI lineages, and disclosed small intra-lineage polymorphisms amongst isolates from Amazonia. These data are important in understanding the complexity of the transmission cycles, genetic structure, and evolutionary history of T. cruzi populations circulating in Amazonia, and they contribute to both the unravelling of human infection routes and the pathological peculiarities of Chagas disease in this region.


Assuntos
Doença de Chagas/veterinária , Insetos Vetores/parasitologia , Doenças dos Macacos/parasitologia , Rhodnius/parasitologia , Trypanosoma cruzi/classificação , Animais , Aotidae/parasitologia , Brasil/epidemiologia , Cebidae/parasitologia , Doença de Chagas/epidemiologia , Doença de Chagas/parasitologia , Doença de Chagas/transmissão , Citocromos b/genética , DNA de Protozoário/genética , Genótipo , Humanos , Doenças dos Macacos/epidemiologia , Filogenia , Polimorfismo Genético , Primatas/parasitologia , Técnica de Amplificação ao Acaso de DNA Polimórfico/métodos , Saguinus/parasitologia , Especificidade da Espécie , Trypanosoma cruzi/genética , Trypanosoma cruzi/isolamento & purificação
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