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1.
Dis Aquat Organ ; 158: 133-141, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38813854

RESUMO

A novel microsporidium was observed in wild swamp guppies Micropoecilia picta from Levera Pond within Levera National Park Grenada, West Indies. Initial observations indicated similarity with Pseudoloma neurophilia, an important pathogen in zebrafish Danio rerio. P. neurophilia exhibit broad host specifity, including members of the family Poecillidae, and both parasites infect the central nervous system. However, spore morphology and molecular phylogeny based on rDNA showed that the swamp guppy microsporidium (SGM) is distinct from P. neurophilia and related microsporidia (Microsporidium cerebralis and M. luceopercae). Spores of the SGM were smaller than others in the clade (3.6 µm long). Differences were also noted in histology; the SGM formed large aggregates of spores within neural tissues along with a high incidence of numerous smaller aggregates and single spores within the surface tissue along the ventricular spaces that extended submeninx, whereas P. neurophilia and M. cerebralis infect deep into the neuropile and cause associated lesions. Analysis of small subunit ribosomal DNA sequences showed that the SGM was <93% similar to these related microsporidia. Nevertheless, one of 2 commonly used PCR tests for P. neurophilia cross reacted with tissues infected with SGM. These data suggest that there could be other related microsporidia capable of infecting zebrafish and other laboratory fishes that are not being detected by these highly specific assays. Consequently, exclusive use of these PCR tests may not accurately diagnose other related microsporidia infecting animals in laboratory and ornamental fish facilities.


Assuntos
Doenças dos Peixes , Microsporídios , Microsporidiose , Filogenia , Poecilia , Animais , Doenças dos Peixes/microbiologia , Doenças dos Peixes/parasitologia , Microsporídios/genética , Microsporídios/isolamento & purificação , Microsporídios/classificação , Microsporidiose/veterinária , Microsporidiose/microbiologia , Granada/epidemiologia
2.
J Invertebr Pathol ; 200: 107958, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37429541

RESUMO

Several PCR methodologies are available for the detection of Enterocytozoon hepatopenaei (EHP) that target the SSU rRNA gene. However, these methodologies are reported as unsuitable for the detection of EHP due to specificity issues. Here, we report the applicability of two commonly used SSU rRNA methodologies for the detection of additional microsporidia from the genus Vittaforma that is present in cultured Penaeus vannamei from Costa Rica. The molecular detection of DNA of the novel microsporidia can only be achieved using SSU rRNA targeting methodologies and does not cross-react with the highly specific spore wall protein gene PCR detection method.


Assuntos
Enterocytozoon , Microsporídios não Classificados , Microsporídios , Penaeidae , Animais , Microsporídios não Classificados/genética , Penaeidae/genética , Vittaforma/genética , Costa Rica , Reação em Cadeia da Polimerase/métodos , Enterocytozoon/genética , Microsporídios/genética , RNA Ribossômico
3.
J Invertebr Pathol ; 198: 107908, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36878425

RESUMO

Carcinus spp. are global aquatic invaders and carriers of several parasites, including a taxonomically unrecognised microsporidian recently observed from Argentina. We provide genome drafts for two parasite isolates, one from Carcinus maenas and one from Carcinus aestuarii, and use multi-gene phylogenetics and genome comparison methods to outline their similarities. Their SSU genes are 100 % similar and other genes have an average similarity of 99.31 %. We informally name the parasite Agmasoma carcini, terming the isolates Ac. var. aestuarii and Ac. var. maenas, following the wealth of genomic data available for each. This study follows on from Frizzera et al. (2021), where this parasite was first histologically identified.


Assuntos
Braquiúros , Microsporídios , Parasitos , Animais , Braquiúros/parasitologia , Microsporídios/genética , Argentina , Genômica
4.
J Eukaryot Microbiol ; 69(3): e12902, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35279911

RESUMO

Speciation is a complex and continuous process that makes the delineation of species boundaries a challenging task in particular in species with little morphological differentiation, such as parasites. In this case, the use of genomic data is often necessary, such as for the intracellular Microsporidian parasites. Here, we characterize the genome of a gut parasite of the cladoceran Daphnia longispina (isolate FI-F-10), which we propose as a new species within the genus Ordospora: Ordospora pajunii sp. nov (Ordosporidae). FI-F-10 closest relative, Ordospora colligata is only found in D. magna. Both microsporidian species share several morphological features. Although it is not possible to estimate divergence times for Microsporidia due to the lack of fossil records and accelerated evolutionary rates, we base our proposal on the phylogenomic and genomic distances between both microsporidian lineages. The phylogenomic reconstruction shows that FI-F-10 forms an early diverging branch basal to the cluster that contains all known O. colligata strains. Whole-genome comparisons show that FI-F-10 presents a greater divergence at the sequence level than observed among O. colligata strains, and its genomic average nucleotide identity (ANI) values against O. colligata are beyond the intraspecific range previously established for yeast and prokaryotes. Our data confirm that the ANI metrics are useful for fine genetic divergence calibration across Microsporidia taxa. In combination with phylogenetic and ecological data, genome-based metrics provide a powerful approach to delimitate species boundaries.


Assuntos
Microsporídios , Parasitos , Animais , Daphnia/genética , Daphnia/parasitologia , Genômica , Microsporídios/genética , Filogenia
5.
PLoS Negl Trop Dis ; 15(12): e0009942, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34928947

RESUMO

BACKGROUND: Secondary symbionts of insects include a range of bacteria and fungi that perform various functional roles on their hosts, such as fitness, tolerance to heat stress, susceptibility to insecticides and effects on reproduction. These endosymbionts could have the potential to shape microbial communites and high potential to develop strategies for mosquito-borne disease control. METHODOLOGY/PRINCIPAL FINDINGS: The relative frequency and molecular phylogeny of Wolbachia, Microsporidia and Cardinium were determined of phlebotomine sand flies and mosquitoes in two regions from Colombia. Illumina Miseq using the 16S rRNA gene as a biomarker was conducted to examine the microbiota. Different percentages of natural infection by Wolbachia, Cardinium, and Microsporidia in phlebotomines and mosquitoes were detected. Phylogenetic analysis of Wolbachia shows putative new strains of Lutzomyia gomezi (wLgom), Brumptomyia hamata (wBrham), and a putative new group associated with Culex nigripalpus (Cnig) from the Andean region, located in Supergroup A and Supergroup B, respectively. The sequences of Microsporidia were obtained of Pi. pia and Cx. nigripalpus, which are located on phylogeny in the IV clade (terrestrial origin). The Cardinium of Tr. triramula and Ps. shannoni were located in group C next to Culicoides sequences while Cardinium of Mi. cayennensis formed two putative new subgroups of Cardinium in group A. In total were obtained 550 bacterial amplicon sequence variants (ASVs) and 189 taxa to the genus level. The microbiota profiles of Sand flies and mosquitoes showed mainly at the phylum level to Proteobacteria (67.6%), Firmicutes (17.9%) and Actinobacteria (7.4%). High percentages of relative abundance for Wolbachia (30%-83%) in Lu. gomezi, Ev. dubitans, Mi. micropyga, Br. hamata, and Cx. nigripalpus were found. ASVs assigned as Microsporidia were found in greater abundance in Pi. pia (23%) and Cx. nigripalpus (11%). An important finding is the detection of Rickettsia in Pi. pia (58,8%) and Bartonella sp. in Cx. nigripalpus. CONCLUSIONS/SIGNIFICANCE: We found that Wolbachia infection significantly decreased the alpha diversity and negatively impacts the number of taxa on sand flies and Culex nigripalpus. The Principal Coordinate Analysis (PCoA) is consistent, which showed statistically significant differences (PERMANOVA, F = 2.4744; R2 = 0.18363; p-value = 0.007) between the microbiota of sand flies and mosquitoes depending on its origin, host and possibly for the abundance of some endosymbionts (Wolbachia, Rickettsia).


Assuntos
Bacteroidetes/isolamento & purificação , Culex/microbiologia , Microbiota , Microsporídios/isolamento & purificação , Filogenia , Psychodidae/microbiologia , Wolbachia/isolamento & purificação , Animais , Bacteroidetes/classificação , Bacteroidetes/genética , Bacteroidetes/fisiologia , Biodiversidade , Colômbia , Culex/fisiologia , Microsporídios/classificação , Microsporídios/genética , Microsporídios/fisiologia , Psychodidae/fisiologia , Simbiose , Wolbachia/classificação , Wolbachia/genética , Wolbachia/fisiologia
6.
Rev. argent. microbiol ; 53(2): 1-10, June 2021. graf
Artigo em Inglês | LILACS | ID: biblio-1376402

RESUMO

Abstract Microsporidia are obligate intracellular fungi with a remarkable ability to infect a wide range of invertebrate and vertebrate hosts. Namely, Enterocytozoon bieneusi is the most frequently microsporidia reported worldwide, and mainly associated with chronic diarrea and wasting syndrome in AIDS patients. Microscopy and PCR-based detection techniques are effective for diagnosis and identification of species and genotypes; however, these methods should be standardized in each laboratory. In this study, we performed microscopy and nested PCR techniques with PCR product sequencing to detect E. bieneusi in human stool samples. These techniques, if applied together, might prove useful for diagnosis and future epidemiological studies of intestinal microsporidiosis in Argentina.


Resumen Los microsporidios son hongos intracelulares obligados con una notable capacidad para infectar una amplia gama de hospedadores invertebrados y vertebrados. Enterocytozoon bieneusi es el microsporidio más frecuentemente reportado en todo el mundo, principalmente tricrómicaasociado con diarrea crónica y síndrome debilitante en pacientes con sida. Las técnicas dedetección basadas en microscopía y PCR son útiles para el diagnóstico y la identificación deespecies y genotipos, pero estos métodos deben estar estandarizados en cada laboratorio.En este estudio evaluamos técnicas de microscopía y PCR anidada, con secuenciación de losproductos, para detectar E. bieneusi en muestras de heces humanas. Estas técnicas, usadas con-juntamente, podrían ser útiles para su aplicación en el diagnóstico de microsporidiosis intestinaly para realizar estudios epidemiológicos de esta afección en Argentina.


Assuntos
Humanos , Microsporídios , Enterocytozoon , Esporos Fúngicos , Reação em Cadeia da Polimerase , Microsporídios/genética , Enterocytozoon/genética , Fezes
7.
Rev Argent Microbiol ; 53(2): 124-128, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32595002

RESUMO

Microsporidia are obligate intracellular fungi with a remarkable ability to infect a wide range of invertebrate and vertebrate hosts. Namely, Enterocytozoon bieneusi is the most frequently microsporidia reported worldwide, and mainly associated with chronic diarrhea and wasting syndrome in AIDS patients. Microscopy and PCR-based detection techniques are effective for diagnosis and identification of species and genotypes; however, these methods should be standardized in each laboratory. In this study, we performed microscopy and nested PCR techniques with PCR product sequencing to detect E. bieneusi in human stool samples. These techniques, if applied together, might prove useful for diagnosis and future epidemiological studies of intestinal microsporidiosis in Argentina.


Assuntos
Enterocytozoon , Microsporídios , Enterocytozoon/genética , Fezes , Humanos , Microsporídios/genética , Reação em Cadeia da Polimerase , Esporos Fúngicos
8.
Med Mycol ; 58(8): 1191-1194, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-32497173

RESUMO

Pneumocystis jirovecii and microsporidia species are recognized as opportunistic infectious pathogens in AIDS patients. Coinfection of both in one patient has been rarely reported. The aim of the present study was to investigate the coinfection of P. jirovecii and microsporidia in different tissues from AIDS deceased patients. Post mortem histological finding of P. jirovecii and microsporidia was demonstrated by means of the Grocott's methenamine silver and Brown Brenn staining, respectively. Molecular technique was used for identification and characterization of both fungi. Out of the 514 autopsied cases P. jirovecii and microsporidia species were identified in 53 (10.3%) and 62 (12.1%) cases respectively. A total of five cases (0.97%) coinfected with Pneumocystis and microsporidia were recovered from all analyzed autopsies. Coinfection of Pneumocystis and microsporidia is very challenging and raises interesting issues about host-parasite relationship. The early diagnosis of both pathogens must be crucial to establish correct and early treatments, improve the patient's evolution, reducing the risk of death.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Coinfecção/microbiologia , Microsporídios/isolamento & purificação , Pneumocystis carinii/isolamento & purificação , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Adulto , Autopsia , Coinfecção/epidemiologia , Feminino , Humanos , Masculino , Microsporídios/genética , Pessoa de Meia-Idade , Pneumocystis carinii/genética , Adulto Jovem
9.
Genome Biol Evol ; 12(1): 3599-3614, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31825473

RESUMO

Microsporidia have the leanest genomes among eukaryotes, and their physiological and genomic simplicity has been attributed to their intracellular, obligate parasitic life-style. However, not all microsporidia genomes are small or lean, with the largest dwarfing the smallest ones by at least an order of magnitude. To better understand the evolutionary mechanisms behind this genomic diversification, we explore here two clades of microsporidia with distinct life histories, Ordospora and Hamiltosporidium, parasitizing the same host species, Daphnia magna. Based on seven newly assembled genomes, we show that mixed-mode transmission (the combination of horizontal and vertical transmission), which occurs in Hamiltosporidium, is found to be associated with larger and AT-biased genomes, more genes, and longer intergenic regions, as compared with the exclusively horizontally transmitted Ordospora. Furthermore, the Hamiltosporidium genome assemblies contain a variety of repetitive elements and long segmental duplications. We show that there is an excess of nonsynonymous substitutions in the microsporidia with mixed-mode transmission, which cannot be solely attributed to the lack of recombination, suggesting that bursts of genome size in these microsporidia result primarily from genetic drift. Overall, these findings suggest that the switch from a horizontal-only to a mixed mode of transmission likely produces population bottlenecks in Hamiltosporidium species, therefore reducing the effectiveness of natural selection, and allowing their genomic features to be largely shaped by nonadaptive processes.


Assuntos
Evolução Molecular , Genoma Fúngico , Microsporídios/genética , Transferência Genética Horizontal , Deriva Genética , Recombinação Genética , Seleção Genética
10.
Acta Parasitol ; 64(3): 658-669, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31286356

RESUMO

PURPOSE: Microsporidiosis is an opportunistic infection that produces chronic diarrhoea and cholangiopathy in patients with AIDS, mainly caused by two species of microsporidia, Enterocytozoon bieneusi and Encephalitozon intestinalis. The aim of this work was to develop an integral system for the diagnosis of microsporidiosis of the intestine and biliary tract in HIV-infected patients, comprising microscopic and molecular techniques. METHODS: The study population comprised 143 adult patients of both sexes with diagnosis of HIV infection, with chronic diarrhoea, and with or without HIV-associated cholangiopathy. Stool studies for microsporidia identification of spores were performed on each patient. A video esofagogastroduodenoscopy with biopsy collection was also carried out for routine histology and semi-thin sections stained with Azure II. Species identification was carried out by transmission electron microscopy and/or polymerase chain reaction for the species E. bieneusi and E. intestinalis. RESULTS: Out of the 143 patients a total of 12.6% (n = 18) were infected with microsporidia. Microsporidia species identified in most cases was E. bieneusi (16/18 cases), followed by E. intestinalis (4/18), all of these last ones in coinfection with E. bieneusi. CONCLUSIONS: Clinical, imaging, microscopic and molecular analyses, when applied in a systematic and integrated approach, allow diagnosis and identification of microsporidia at species level in AIDS patients with chronic diarrhoea, and with or without HIV-associated cholangiopathy.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Infecções por HIV/complicações , Microsporídios/isolamento & purificação , Microsporidiose/microbiologia , Infecções Oportunistas Relacionadas com a AIDS/etiologia , Adulto , Diarreia/etiologia , Diarreia/microbiologia , Fezes/microbiologia , Feminino , Trato Gastrointestinal/microbiologia , Humanos , Masculino , Microsporídios/classificação , Microsporídios/genética , Microsporidiose/etiologia , Pessoa de Meia-Idade , Adulto Jovem
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