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1.
Parasite ; 28: 12, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33620310

RESUMO

Orthoptera are infected by about 60 species of gregarines assigned to the genus Gregarina Dufour, 1828. Among these species, Gregarina garnhami Canning, 1956 from Schistocerca gregaria (Forsskål, 1775) was considered by Lipa et al. in 1996 to be synonymous with Gregarina acridiorum (Léger 1893), a parasite of several orthopteran species including Locusta migratoria (Linné, 1758). Here, a morphological study and molecular analyses of the SSU rDNA marker demonstrate that specimens of S. gregaria and specimens of L. migratoria are infected by two distinct Gregarina species, G. garnhami and G. acridiorum, respectively. Validation of the species confirms that molecular analyses provide useful taxonomical information. Phenotypic plasticity was clearly observed in the case of G. garnhami: the morphology of its trophozoites, gamonts and syzygies varied according to the geographical location of S. gregaria and the subspecies infected.


Assuntos
Apicomplexa/classificação , Especiação Genética , Locusta migratoria/parasitologia , Animais , DNA Ribossômico/genética
2.
Parasitol Res ; 119(11): 3739-3753, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33000433

RESUMO

Many tick-borne pathogens (TBPs) are present in wildlife. The objective of this study is to reveal the role of wild bears in maintaining TBPs. A total of 49 brown bears (Ursus arctos yesoensis) from Hokkaido, and 18 Japanese black bears (Ursus thibetanus japonicus) from Tochigi, and 66 Japanese black bears from Nagano were examined by two molecular methods, reverse line blot (RLB) hybridization, and nested PCR. A total of 5 TBPs (Hepatozoon ursi, Babesia sp. UR2-like group, Cytauxzoon sp. UR1, Babesia sp. UR1, and Babesia microti) were detected from bear blood DNA samples. B. microti was detected from blood DNA samples of Japanese black bear for the first time, with the prevalence of 6.0% (5/84). Out of detected pathogens, H. ursi, Babesia sp. UR2-like pathogens, and Cytauxzoon sp. UR1 were considered as three of the most prevalent TBPs in bears. The prevalence of H. ursi were significantly higher in Japanese black bear (0% vs 96.4%) while that of Babesia sp. UR2-like group was higher in Hokkaido brown bears (89.8% vs 40.5%). The prevalence of Babesia sp. UR1 were significantly higher in Japanese black bears from Tochigi (44.4%), comparing with those from Nagano (18.2%). The prevalence of the detected TBPs were significantly higher in adult bears, comparing with those in younger bears. The present study suggests that Japanese bear species contribute in the transmission of several TBPs in Japan. The expanding distribution of bears might cause the accidental transmission of TBPs to humans and domestic animals.


Assuntos
Apicomplexa/isolamento & purificação , Infecções Protozoárias em Animais/parasitologia , Ursidae/parasitologia , Animais , Animais Selvagens/parasitologia , Apicomplexa/classificação , Apicomplexa/genética , DNA de Protozoário/genética , Japão/epidemiologia , Prevalência , Infecções Protozoárias em Animais/epidemiologia , Infecções Protozoárias em Animais/transmissão , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/parasitologia , Doenças Transmitidas por Carrapatos/transmissão , Carrapatos/parasitologia
3.
Parasitol Res ; 119(10): 3469-3479, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32827104

RESUMO

Amphibians are among the most threatened vertebrate groups in the world, and the main causes include climate change, habitat destruction, and emerging diseases. Herein, we investigated the occurrence and characterized molecularly Apicomplexa in anurans from southeastern Brazil. Forty individuals from seven anuran species were sampled in São Paulo state. In the molecular analyses, one Leptodactylus latrans and one Rhinella diptycha were positive in PCR assays for species of Hepatozoon. Two L. latrans were also positive for coccidian infections (Lankesterella sp. and an unidentified coccidian species). Phylogenetic analysis based on 18S rDNA clustered the sequences detected in anurans from the present study with Hepatozoon spp. detected in reptiles and other anurans from Brazil, albeit they were separate from Hepatozoon haplotypes detected in frogs from Africa and North America. Our study showed, for the first time, the molecular detection of Lankesterella sp. and another coccidian in L. latrans. Additionally, co-infection by different species of Hepatozoon haplotypes and an unidentified coccidian in anurans from Brazil was documented.


Assuntos
Anuros/parasitologia , Apicomplexa/genética , Apicomplexa/isolamento & purificação , Infecções Protozoárias em Animais/parasitologia , Animais , Anuros/classificação , Apicomplexa/classificação , Brasil/epidemiologia , Coccídios/classificação , Coccídios/genética , Coccídios/isolamento & purificação , Coccidiose/epidemiologia , Coccidiose/parasitologia , Coccidiose/veterinária , DNA de Protozoário/genética , DNA Ribossômico/genética , Filogenia , Infecções Protozoárias em Animais/epidemiologia
4.
PLoS Pathog ; 16(8): e1008717, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32745123

RESUMO

Hepatocystis is a genus of single-celled parasites infecting, amongst other hosts, monkeys, bats and squirrels. Although thought to have descended from malaria parasites (Plasmodium spp.), Hepatocystis spp. are thought not to undergo replication in the blood-the part of the Plasmodium life cycle which causes the symptoms of malaria. Furthermore, Hepatocystis is transmitted by biting midges, not mosquitoes. Comparative genomics of Hepatocystis and Plasmodium species therefore presents an opportunity to better understand some of the most important aspects of malaria parasite biology. We were able to generate a draft genome for Hepatocystis sp. using DNA sequencing reads from the blood of a naturally infected red colobus monkey. We provide robust phylogenetic support for Hepatocystis sp. as a sister group to Plasmodium parasites infecting rodents. We show transcriptomic support for a lack of replication in the blood and genomic support for a complete loss of a family of genes involved in red blood cell invasion. Our analyses highlight the rapid evolution of genes involved in parasite vector stages, revealing genes that may be critical for interactions between malaria parasites and mosquitoes.


Assuntos
Apicomplexa/genética , Sangue/parasitologia , Colobus/parasitologia , Malária/veterinária , Doenças dos Macacos/parasitologia , Plasmodium/genética , Infecções Protozoárias em Animais/parasitologia , Animais , Apicomplexa/classificação , Apicomplexa/fisiologia , Genoma de Protozoário , Malária/sangue , Malária/parasitologia , Doenças dos Macacos/sangue , Filogenia , Plasmodium/classificação , Plasmodium/fisiologia , Infecções Protozoárias em Animais/sangue , Transcriptoma
5.
Rev Bras Parasitol Vet ; 29(3): e000920, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32667500

RESUMO

The aim of this study was to verify the presence and identify the species of haemosporidian parasites in eared doves (Zenaida auriculata) in Brazil. Two hundred and eleven male and female eared doves were trap-captured in four different regions of Londrina city, in southern Brazil. Whole blood was collected in EDTA tubes through heart puncture after euthanasia in a CO2 chamber. A nested PCR targeting the mitochondrial cytochrome b gene (cyt b) of Haemoproteus spp./Plasmodium spp. was performed, followed by an enzymatic digestion to identify the genus. Phylogenetic trees were constructed to determine the closely related species. Out of 211 eared doves, 209 (99.05%) were positive for Haemoproteus spp. and/or Plasmodium spp. RFLP analysis showed that 72.72% (152/209) of eared doves were positive only for Haemoproteus spp., 6.22% (13/209) were positive only for Plasmodium spp., and 21.05% (44/209) of eared doves had mixed infections. Genetic analysis found four samples that were homologous with Haemoproteus multipigmentatus and one that was homologous with Plasmodium sp. This is the first molecular study of hemoparasites from eared doves in Brazil, and it is also the first description of H. multipigmentatus and Plasmodium spp. infection in eared doves in Brazil.


Assuntos
Apicomplexa , Doenças das Aves , Columbidae , Plasmodium , Infecções Protozoárias em Animais , Animais , Apicomplexa/classificação , Apicomplexa/genética , Doenças das Aves/diagnóstico , Doenças das Aves/parasitologia , Brasil , Columbidae/parasitologia , Feminino , Masculino , Filogenia , Plasmodium/classificação , Plasmodium/genética , Reação em Cadeia da Polimerase/veterinária , Infecções Protozoárias em Animais/diagnóstico , Infecções Protozoárias em Animais/parasitologia
6.
Trends Parasitol ; 36(9): 727-734, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32680786

RESUMO

Despite the benefits of phototrophy, many algae have lost photosynthesis and have converted back to heterotrophy. Parasitism is a heterotrophic strategy, with apicomplexans being among the most devastating parasites for humans. The presence of a nonphotosynthetic plastid in apicomplexan parasites suggests their phototrophic ancestry. The discovery of related phototrophic chromerids has unlocked the possibility to study the transition between phototrophy and parasitism in the Apicomplexa. The chromerid Chromera velia can live as an intracellular parasite in coral larvae as well as a free-living phototroph, combining phototrophy and parasitism in what I call photoparasitism. Since early-branching apicomplexans live extracellularly, their evolution from an intracellular symbiont is unlikely. In this opinion article I discuss possible evolutionary trajectories from an extracellular photoparasite to an obligatory apicomplexan parasite.


Assuntos
Apicomplexa/classificação , Apicomplexa/fisiologia , Evolução Biológica , Parasitos/classificação , Parasitos/fisiologia , Processos Fototróficos , Animais , Apicomplexa/metabolismo , Humanos , Parasitos/metabolismo
7.
Rev Bras Parasitol Vet ; 29(2): e002420, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32428179

RESUMO

Hepatozoon pyramidumi sp. n. is described from the blood of the Egyptian saw-scaled viper, Echis pyramidum, captured from Saudi Arabia. Five out of ten viper specimens examined (50%) were found infected with Hepatozoon pyramidumi sp. n. with parasitaemia level ranged from 20-30%. The infection was restricted only to the erythrocytes. Two morphologically different forms of intraerythrocytic stages were observed; small and mature gamonts. The small ganomt with average size of 10.7 × 3.5 µm. Mature gamont was sausage-shaped with recurved poles measuring 16.3 × 4.2 µm in average size. Infected erythrocytes were hypertrophied; their nuclei were deformed and sometimes displaced from their central position in the normal uninfected cell. Merogonic stages were observed in the lung endothelial cell and the liver parenchyma cells. Mature meront was 17.8 × 13.6 µm and contained banana-shaped merozoites with average size of ~15 × 2 µm. Phylogenetic analysis based on the SSU rDNA sequence clustered Hepatozoon pyramidumi sp. n with previously sequenced Hepatozoon spp., most of them infected reptilian hosts without geographic consideration. The morphological and molecular comparison with closely related species proved the taxonomic uniqueness and novelty of the present form.


Assuntos
Apicomplexa/genética , Apicomplexa/fisiologia , DNA de Protozoário/genética , Viperidae/parasitologia , Animais , Apicomplexa/classificação , DNA Ribossômico/genética , Eritrócitos/parasitologia , Eritrócitos/patologia , Fígado/parasitologia , Fígado/patologia , Pulmão/parasitologia , Pulmão/patologia , Parasitemia/parasitologia , Parasitemia/veterinária , Filogenia , Arábia Saudita , Análise de Sequência de DNA , Viperidae/sangue
8.
Eur J Protistol ; 73: 125688, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32143143

RESUMO

The molecular divergence, morphology and pathology of a cryptic gregarine that is related to the bee parasite Apicystis bombi Lipa and Triggiani, 1996 is described. The 18S ribosomal DNA gene sequence of the new gregarine was equally dissimilar to that of A. bombi and the closest related genus Mattesia Naville, 1930, although phylogenetic analysis supported a closer relation to A. bombi. Pronounced divergence with A. bombi was found in the ITS1 sequence (69.6% similarity) and seven protein-coding genes (nucleotide 78.05% and protein 90.2% similarity). The new gregarine was isolated from a Bombus pascuorum Scopoli, 1763 female and caused heavy hypertrophism of the fat body tissue in its host. In addition, infected cells of the hypopharyngeal gland tissue, an important excretory organ of the host, were observed. Mature oocysts were navicular in shape and contained four sporozoites, similar to A. bombi oocysts. Given these characteristics, we proposed the name Apicystis cryptica sp. n. Detections so far indicated that distribution and host species occupation of Apicystis spp. overlap at least in Europe, and that historical detections could not discriminate between them. Specific molecular assays were developed that can be implemented in future pathogen screens that aim to discriminate Apicystis spp. in bees.


Assuntos
Apicomplexa/classificação , Abelhas/parasitologia , Animais , Apicomplexa/citologia , Apicomplexa/genética , DNA de Protozoário/genética , Europa (Continente) , Corpo Adiposo/parasitologia , Oocistos/citologia , Especificidade da Espécie
9.
J Eukaryot Microbiol ; 67(1): 4-17, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31231936

RESUMO

Eugregarines are understudied apicomplexan parasites of invertebrates inhabiting marine, freshwater, and terrestrial environments. Most currently known terrestrial eugregarines have been described parasitizing the gut from less than 1% of total insect diversity, with a high likelihood that the remaining insect species are infected. Eugregarine diversity in orthopterans (grasshoppers, locusts, katydids, and crickets) is still little known. We carried out a survey of the eugregarines parasitizing the Mexican lubber grasshopper, Taeniopoda centurio, an endemic species to the northwest of Mexico. We described two new eugregarine species from the gut of the host: Amoebogregarina taeniopoda n. sp. and Quadruspinospora mexicana n. sp. Both species are morphologically dissimilar in their life-cycle stages. Our SSU rDNA phylogenetic analysis showed that both species are phylogenetically distant to each other, even though they parasitize the same host. Amoebogregarina taeniopoda n. sp. clustered within the clade Gregarinoidea, being closely related to Amoebogregarina nigra from the grasshopper Melanoplus differentialis. Quadruspinospora mexicana n. sp. clustered within the clade Actinocephaloidea and grouped with Prismatospora evansi, a parasite from dragonfly naiads. Amoebogregarina taeniopoda n. sp. and Q. mexicana n. sp. represent the first record of eugregarines found to infect a species of the family Romaleidae.


Assuntos
Apicomplexa/classificação , Apicomplexa/citologia , Gafanhotos/parasitologia , Interações Hospedeiro-Parasita , Filogenia , Animais , Apicomplexa/ultraestrutura , DNA de Protozoário/análise , DNA Ribossômico/análise , México , Microscopia , Microscopia Eletrônica de Varredura , Análise de Sequência de DNA
10.
Protist ; 171(1): 125710, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31884404

RESUMO

This study set out to bolster morphological and molecular datasets of marine gregarine apicomplexans. Gregarines were sampled from the Sea of Japan and Northwest Pacific from cirratuliform polychaetes (Acrocirridae, Cirratulidae, and Flabelligeridae), as well as sipunculids. Trophozoites (feeding stages) were gathered for identification using light microscopy, scanning electron microscopy, and transmission electron microscopy. Cells were also collected for molecular phylogenetic analysis using 18S rDNA and 28S rDNA. As a result, three new species of Selenidium, S. planusae n. sp., S. validusae n. sp., and S. pyroidea n. sp. were described, and additional morphological and genetic data were gathered for an existing species, S. orientale; and Trollidium was established as a new genus. Trollidium akkeshiense n. gen. n. sp. possessed a unique, unsymmetrical organization of microtubules running the longitudinal length of one side of the trophozoite, corresponding to a zig-zag pattern of epicytic (surface) folds, and a flicking pattern of movement. Phylogenetic analyses of 18S rDNA and 28S rDNA showed that these portions of the ribosomal operon are able to resolve some relationships among Selenidium, while other lineages including Trollidium akkeshiense n. gen. n. sp. appeared to be highly influenced by long branch attraction. High evolutionary rates along the ribosomal operon of gregarines may hinder this marker from resolving deeper nodes among early apicomplexans.


Assuntos
Apicomplexa/classificação , Apicomplexa/genética , Organismos Aquáticos/classificação , Organismos Aquáticos/genética , Filogenia , DNA Ribossômico/genética , Oceano Pacífico , Especificidade da Espécie
11.
Database (Oxford) ; 20192019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31529106

RESUMO

Despite significant progress in apicomplexan genome sequencing and genomics, the current list of experimentally validated transcription factors (TFs) in these genomes is incomplete and mainly consists of AP2 family of proteins, with only a limited number of non-AP2 family TFs and transcription-associated co-factors (TcoFs). We have performed a systematic bioinformatics-aided prediction of TFs and TcoFs in apicomplexan genomes and developed the ApicoTFdb database which consists of experimentally validated as well as computationally predicted TFs and TcoFs in 14 apicomplexan species. The predicted TFs are manually curated to complement the existing annotations. The current version of the database includes 1292 TFs which includes experimentally validated and computationally predicted TFs, representing 20 distinct families across 14 apicomplexan species. The predictions include TFs of TUB, NAC, BSD, HTH, Cupin/Jumonji, winged helix and FHA family proteins, not reported earlier as TFs in the genomes. Apart from TFs, ApicoTFdb also classifies TcoFs into three main subclasses: TRs, CRRs and RNARs, representing 2491 TcoFs in 14 apicomplexan species, are analyzed in this study. The database is designed to integrate different tools for comparative analysis. All entries in the database are dynamically linked with other databases, literature reference, protein-protein interactions, pathways and annotations associated with each protein. ApicoTFdb will be useful to the researchers interested in less-studied gene regulatory mechanisms mediating the complex life cycle of the apicomplexan parasites. The database will aid in the discovery of novel drug targets to much needed combat the growing drug resistance in the parasites.


Assuntos
Apicomplexa/genética , Bases de Dados de Proteínas , Internet , Proteínas de Protozoários/genética , Fatores de Transcrição/genética , Apicomplexa/classificação
12.
Curr Biol ; 29(17): 2936-2941.e5, 2019 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-31422883

RESUMO

The apicomplexans are a group of obligate animal pathogens that include Plasmodium (malaria), Toxoplasma (toxoplasmosis), and Cryptosporidium (cryptosporidiosis) [1]. They are an extremely diverse and specious group but are nevertheless united by a distinctive suite of cytoskeletal and secretory structures related to infection, called the apical complex, which is used to recognize and gain entry into animal host cells. The apicomplexans are also known to have evolved from free-living photosynthetic ancestors and retain a relict plastid (the apicoplast), which is non-photosynthetic but houses a number of other essential metabolic pathways [2]. Their closest relatives include a mix of both photosynthetic algae (chromerids) and non-photosynthetic microbial predators (colpodellids) [3]. Genomic analyses of these free-living relatives have revealed a great deal about how the alga-parasite transition may have taken place, as well as origins of parasitism more generally [4]. Here, we show that, despite the surprisingly complex origin of apicomplexans from algae, this transition actually occurred at least three times independently. Using single-cell genomics and transcriptomics from diverse uncultivated parasites, we find that two genera previously classified within the Apicomplexa, Piridium and Platyproteum, form separately branching lineages in phylogenomic analyses. Both retain cryptic plastids with genomic and metabolic features convergent with apicomplexans. These findings suggest a predilection in this lineage for both the convergent loss of photosynthesis and transition to parasitism, resulting in multiple lineages of superficially similar animal parasites.


Assuntos
Apicomplexa/classificação , Evolução Biológica , Animais , Apicoplastos/classificação , Parasitos/classificação , Filogenia
13.
Elife ; 82019 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-31418692

RESUMO

The phylum Apicomplexa comprises human pathogens such as Plasmodium but is also an under-explored hotspot of evolutionary diversity central to understanding the origins of parasitism and non-photosynthetic plastids. We generated single-cell transcriptomes for all major apicomplexan groups lacking large-scale sequence data. Phylogenetic analysis reveals that apicomplexan-like parasites are polyphyletic and their similar morphologies emerged convergently at least three times. Gregarines and eugregarines are monophyletic, against most expectations, and rhytidocystids and Eleutheroschizon are sister lineages to medically important taxa. Although previously unrecognized, plastids in deep-branching apicomplexans are common, and they contain some of the most divergent and AT-rich genomes ever found. In eugregarines, however, plastids are either abnormally reduced or absent, thus increasing known plastid losses in eukaryotes from two to four. Environmental sequences of ten novel plastid lineages and structural innovations in plastid proteins confirm that plastids in apicomplexans and their relatives are widespread and share a common, photosynthetic origin.


Assuntos
Apicomplexa/classificação , Apicomplexa/crescimento & desenvolvimento , Apicoplastos/metabolismo , Variação Genética , Apicomplexa/genética , Apicoplastos/genética , Evolução Molecular , Perfilação da Expressão Gênica , Filogenia
14.
Genome Biol Evol ; 11(10): 2727-2740, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31328784

RESUMO

A most interesting exception within the parasitic Apicomplexa is Nephromyces, an extracellular, probably mutualistic, endosymbiont found living inside molgulid ascidian tunicates (i.e., sea squirts). Even though Nephromyces is now known to be an apicomplexan, many other questions about its nature remain unanswered. To gain further insights into the biology and evolutionary history of this unusual apicomplexan, we aimed to 1) find the precise phylogenetic position of Nephromyces within the Apicomplexa, 2) search for the apicoplast genome of Nephromyces, and 3) infer the major metabolic pathways in the apicoplast of Nephromyces. To do this, we sequenced a metagenome and a metatranscriptome from the molgulid renal sac, the specialized habitat where Nephromyces thrives. Our phylogenetic analyses of conserved nucleus-encoded genes robustly suggest that Nephromyces is a novel lineage sister to the Hematozoa, which comprises both the Haemosporidia (e.g., Plasmodium) and the Piroplasmida (e.g., Babesia and Theileria). Furthermore, a survey of the renal sac metagenome revealed 13 small contigs that closely resemble the genomes of the nonphotosynthetic reduced plastids, or apicoplasts, of other apicomplexans. We show that these apicoplast genomes correspond to a diverse set of most closely related but genetically divergent Nephromyces lineages that co-inhabit a single tunicate host. In addition, the apicoplast of Nephromyces appears to have retained all biosynthetic pathways inferred to have been ancestral to parasitic apicomplexans. Our results shed light on the evolutionary history of the only probably mutualistic apicomplexan known, Nephromyces, and provide context for a better understanding of its life style and intricate symbiosis.


Assuntos
Apicomplexa/genética , Apicoplastos/genética , Genoma , Apicomplexa/classificação , Núcleo Celular/genética , Redes e Vias Metabólicas/genética , Filogenia
15.
Parasit Vectors ; 12(1): 193, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31046822

RESUMO

BACKGROUND: The epidemiology of feline vector-borne pathogens (FeVBPs) has been less investigated in cats than in dogs. The present study assessed the prevalence of Rickettsia spp., Babesia spp., Cytauxzoon spp. and Leishmania infantum infections in cat populations living in central Italy, by molecular and serological tools. RESULTS: A total of 286 healthy cats were randomly selected from catteries and colonies in central Italy. Peripheral blood and conjunctival swab (CS) samples were collected during surgical procedures for regional neutering projects. Sera were analysed by IFAT to detect anti-Rickettsia felis, R. conorii, Babesia microti and Leishmania IgG antibodies using commercial and home-made antigens. DNA extracted from buffy coats (BCs) was tested for Rickettsia spp., and Piroplasmida species, including Cytauxzoon spp. and Babesia spp. by PCR. Buffy coats and CS samples were assayed by a nested (n)-PCR for Leishmania spp. Sixty-two cats (21.67%) were seropositive to at least one of the tested pathogens. The serological assay revealed 23 (8.04%) and 18 (6.29%) positive cats for R. felis and R. conorii, respectively, with low titers (1/64-1/128). No antibodies against B. microti were detected. Neither Rickettsia nor Piroplasmida DNA were amplified using the specific PCR assays. Thirty-one cats (10.83%) tested positive to anti-Leishmania IgG, with titers ranging from 1:40 to 1:160 and 45 animals (15.73%) tested positive to Leishmania CS n-PCR, whereas none of the animals tested positive to BC n-PCR. Considering the results obtained by IFAT and CS n-PCR, a moderate agreement between the two tests was detected (κ = 0.27). CONCLUSIONS: The results of the serological and molecular surveys showed a moderate exposure to Leishmania in the investigated cats and highlighted the limited molecular diagnostic value of BC versus CS samples for this pathogen. Conversely no evidence supported the circulation of Cytauxzoon spp. in domestic cats, in contrast with previous detections in European wild cats in the same areas monitored. The low positive titres for R. felis in association with no DNA BC amplification prevent speculation on the exposure of feline populations to this FeVBP due to the cross-reactivity existing within spotted fever group rickettsiosis (SFGR).


Assuntos
Apicomplexa/isolamento & purificação , Babesia/isolamento & purificação , Doenças do Gato/microbiologia , Doenças do Gato/parasitologia , Doenças Transmissíveis Emergentes/veterinária , Leishmania infantum/isolamento & purificação , Infecções Protozoárias em Animais/parasitologia , Infecções por Rickettsia/veterinária , Rickettsia/isolamento & purificação , Animais , Apicomplexa/classificação , Apicomplexa/genética , Babesia/classificação , Babesia/genética , Doenças do Gato/epidemiologia , Gatos , Doenças Transmissíveis Emergentes/microbiologia , Doenças Transmissíveis Emergentes/parasitologia , Estudos Transversais , Feminino , Itália/epidemiologia , Leishmania infantum/classificação , Leishmania infantum/genética , Masculino , Rickettsia/classificação , Rickettsia/genética , Infecções por Rickettsia/microbiologia
16.
Parasit Vectors ; 12(1): 172, 2019 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-30992062

RESUMO

Screening of ticks from companion animals from Australia using genetic tools has recently been used to identify and name eight new species of Apicomplexan parasites. However, the diagnosis of these was based on genetic distinctiveness and phylogenetic relationships rather than determination of specific characters, which is required by the International Code of Zoological Nomenclature. The recently proposed names are therefore invalid. The use of informal names is necessary until formal valid descriptions are available.


Assuntos
Apicomplexa/classificação , Carrapatos/parasitologia , Animais , Apicomplexa/isolamento & purificação , Filogenia
17.
Int J Parasitol ; 49(5): 375-387, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30790556

RESUMO

Extrachromosomal genomes of the adeleorinid parasite Hepatozoon canis infecting an Israeli dog were investigated using next-generation and standard sequencing technologies. A complete apicoplast genome and several mitochondrion-associated sequences were generated. The apicoplast genome (31,869 bp) possessed two copies of both large subunit (23S) and small subunit (16S) ribosomal RNA genes (rDNA) within an inverted repeat region, as well as 22 protein-coding sequences, 25 transfer RNA genes (tDNA) and seven open reading frames of unknown function. Although circular-mapping, the apicoplast genome was physically linear according to next-generation data. Unlike other apicoplast genomes, genes encoding ribosomal protein S19 and tDNAs for alanine, aspartic acid, histidine, threonine and valine were not identified. No complete mitochondrial genome was recovered using next-generation data or directed PCR amplifications. Eight mitochondrion-associated (215-3523 bp) contigs assembled from next-generation data encoded a complete cytochrome c oxidase subunit I coding sequence, a complete cytochrome c oxidase subunit III coding sequence, two complete cytochrome B coding sequences, a non-coding, pseudogene for cytochrome B and multiple fragmented mitochondrial rDNA genes (SSUA, SSUB, SSUD, LSUC, LSUG, RNA6, RNA10, RNA14, RNA18). The paucity of NGS reads generating each of the mitochondrion-like sequences suggested that a complete mitochondrial genome at typically high copy number was absent in H. canis. In contrast, the complete nuclear rDNA unit sequence of H. canis (18S rDNA to 28S rDNA, 6977 bp) had >1000-fold next-generation coverage. Multiple divergent (from 93.6% to 99.9% pairwise identities) nuclear 18S rDNA contigs were generated (three types with 10 subtypes total). To our knowledge this is the first apicoplast genome sequenced from any adeleorinid coccidium and the first mitochondrion-associated sequences from this serious pathogen of wild and domestic canids. These newly generated sequences may provide useful genetic loci for high-resolution species-level genotyping that is currently impossible using existing nuclear rDNA targets.


Assuntos
Apicomplexa/genética , Apicoplastos/genética , Genomas de Plastídeos , Mitocôndrias/genética , Animais , Apicomplexa/classificação , Apicomplexa/isolamento & purificação , Citocromos b/genética , DNA de Protozoário/genética , DNA Ribossômico/genética , Doenças do Cão/parasitologia , Cães , Genoma Mitocondrial , Genoma de Protozoário , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Infecções Protozoárias em Animais/parasitologia
18.
Bull Math Biol ; 81(2): 568-597, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30206809

RESUMO

Principal component analysis is a widely used method for the dimensionality reduction of a given data set in a high-dimensional Euclidean space. Here we define and analyze two analogues of principal component analysis in the setting of tropical geometry. In one approach, we study the Stiefel tropical linear space of fixed dimension closest to the data points in the tropical projective torus; in the other approach, we consider the tropical polytope with a fixed number of vertices closest to the data points. We then give approximative algorithms for both approaches and apply them to phylogenetics, testing the methods on simulated phylogenetic data and on an empirical dataset of Apicomplexa genomes.


Assuntos
Filogenia , Análise de Componente Principal , Algoritmos , Apicomplexa/classificação , Apicomplexa/genética , Biologia Computacional , Heurística Computacional , Simulação por Computador , Bases de Dados Genéticas/estatística & dados numéricos , Genoma de Protozoário , Modelos Lineares , Conceitos Matemáticos , Modelos Genéticos , Modelos Estatísticos
19.
Parasitol Res ; 118(1): 235-243, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30474737

RESUMO

Babesia gibsoni (B. gibsoni), an intracellular apicomplexan protozoan, poses great threat to canine health. Currently, little information is available about the B. gibsoni (WH58) endemic to Wuhan, China. Here, the mitochondrial (mt) genome of B. gibsoni (WH58) was amplified by five pairs of primers and sequenced and annotated by alignment with the reported mt genome sequences of Babesia canis (B. canis, KC207822), Babesia orientalis (KF218819), Babesia bovis (AB499088), and Theileria equi (AB499091). The evolutionary relationships were analyzed with the amino acid sequences of cytochrome c oxidase I (cox1) and cytochrome b (cob) genes in apicomplexan parasite species. Additionally, the mt genomes of Babesia, Theileria, and Plasmodium spp. were compared in size, host infection, form, distribution, and direction of the protein-coding genes. The full size of the mt genome of B. gibsoni (WH58) was 5865 bp with a linear form, containing terminal-inverted repeats on both ends, six large subunit ribosomal RNA fragments, and three protein-coding genes: cox1, cob, and cytochrome c oxidase III (cox3). Babesia, Theileria, and Plasmodium spp. had a similar mt genome size of about 6000 bp. The mt genomes of parasites that cause canine babesiosis showed a slightly smaller size than the other species. Moreover, Babesia microti (R1 strain) was about 11,100 bp in size, which was twice larger than that of the other species. The mt form was linear for Babesia and Theileria spp. but circular for Plasmodium falciparum and Plasmodium knowlesi. Additionally, all the species contained the three protein-coding genes of cox1, cox3, and cob except Toxoplasma gondii (RH strain) which only contained the cox1 and cob genes. The phylogenetic analysis indicated that B. gibsoni (WH58) was more identical to B. gibsoni (AB499087), B. canis (KC207822), and Babesia rossi (KC207823) and most divergent from Babesia conradae in Babesia spp. Despite the highest similarity to B. gibsoni (AB499087) reported in Japan, B. gibsoni (WH58) showed notable differences in the sequence of nucleotides and amino acids and the property in virulence to host and in vitro cultivation. This study compared the mt genomes of the two B. gibsoni isolates and other parasites in the phylum Apicomplexa and provided new insights into their differences and evolutionary relationships.


Assuntos
Babesia/isolamento & purificação , Babesiose/parasitologia , Doenças do Cão/parasitologia , Genoma Mitocondrial , Infecções Protozoárias em Animais/parasitologia , Sequência de Aminoácidos , Animais , Apicomplexa/classificação , Apicomplexa/genética , Apicomplexa/isolamento & purificação , Babesia/classificação , Babesia/genética , China/epidemiologia , Citocromos b/genética , Primers do DNA/genética , Cães , Anotação de Sequência Molecular , Filogenia , Infecções Protozoárias em Animais/epidemiologia , Análise de Sequência de DNA
20.
Protist ; 169(6): 826-852, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30453272

RESUMO

Archigregarines are a key group for understanding the early evolution of Apicomplexa. Here we report morphological, ultrastructural, and molecular phylogenetic evidence from two archigregarine species: Selenidium pygospionis sp. n. and S. pherusae sp. n. They exhibited typical features of archigregarines. Additionally, an axial row of vacuoles of a presumably nutrient distribution system was revealed in S. pygospionis. Intracellular stages of S. pygospionis found in the host intestinal epithelium may point to the initial intracellular localization in the course of parasite development. Available archigregarine SSU (18S) rDNA sequences formed four major lineages fitting the taxonomical affiliations of their hosts, but not the morphological or biological features used for the taxonomical revision by Levine (1971). Consequently, the genus Selenidioides Levine, 1971 should be abolished. The branching order of these lineages was unresolved; topology tests rejected neither para- nor monophyly of archigregarines. We provided phylogenies based on LSU (28S) rDNA and near-complete ribosomal operon (concatenated SSU, 5.8S, LSU rDNAs) sequences including S. pygospionis sequences. Although being preliminary, they nevertheless revealed the monophyly of gregarines previously challenged by many molecular phylogenetic studies. Despite their molecular-phylogenetic heterogeneity, archigregarines exhibit an extremely conservative plesiomorphic structure; their ultrastructural key features appear to be symplesiomorphies rather than synapomorphies.


Assuntos
Apicomplexa/classificação , Apicomplexa/isolamento & purificação , Organismos Aquáticos/classificação , Organismos Aquáticos/isolamento & purificação , Filogenia , Animais , Apicomplexa/genética , Apicomplexa/ultraestrutura , Organismos Aquáticos/genética , Organismos Aquáticos/ultraestrutura , Análise por Conglomerados , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Locomoção , Microscopia , Microscopia Eletrônica , Poliquetos/parasitologia , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNA
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