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1.
Infect Genet Evol ; 70: 182-188, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30244093

RESUMO

The centriole in eukaryotes functions as the cell's microtubule-organizing center (MTOC) to nucleate spindle assembly. The evolutionarily conserved protein SAS-6 constitutes the center of the cartwheel assembly that scaffolds centrioles early in their biogenesis. Microsporidia possess the spindle plaque instead of centriole as their MTOC to nucleate spindle assembly. However, little is known about the components of spindle plaques in microsporidia. In our present study, we identified a SAS-6 protein in the microsporidium Nosema bombycis and named it as NSAS-6. The NSAS-6 gene contains a complete ORF of 1104 bp in length that encodes a 367-amino acid polypeptide. NSAS-6 consists of a conserved N-terminal domain and a coiled-coil domain. The high identity of SAS-6 homologous sequences from microsporidia indicates that SAS-6 is a conserved protein in microsporidia. Immunolocalization in sporoplasms, intracellular stages and mature spores showed that NSAS-6 probably localizes to the nucleus of N. bombycis and exists throughout the life cycle of N. bombycis. These results suggest that NSAS-6 is required in cell morphogenesis and division in N. bombycis. The function and structure of NSAS-6 should be the focus for further studies, which is essential to elucidate the role of SAS-6 in spindle plaque assembly.


Assuntos
Proteínas Cromossômicas não Histona/genética , Fuso Acromático/genética , Proteínas Fúngicas/genética , Microsporídios não Classificados/genética , Microsporídios não Classificados/ultraestrutura , Centro Organizador dos Microtúbulos , Nosema/genética , Nosema/ultraestrutura
2.
Dis Aquat Organ ; 129(1): 31-39, 2018 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-29916390

RESUMO

Microsporidial spores were identified in the musculature of a loggerhead sea turtle Caretta caretta found dead on the shore in New Brunswick, Canada. Gastroenteritis was diagnosed on gross postmortem examination, with no gross abnormalities detected in the skeletal muscle. Histologically, the microsporidial spores were associated with inflammation and muscular necrosis and measured 1.1-1.7 × 2.2-3.4 µm. Spores were typically identified within sporophorous vesicles and, less often, in sporophorocysts and were weakly Gram positive, had punctate PAS staining, and were occasionally strongly acid-fast. Ultrastructural characteristics included 7-10 polar filament coils and other standard features of microsporidial spores. PCR for the microsporidial small subunit rRNA gene sequence was performed on DNA extracted from the muscle and small intestine, and the resulting amplicon was sequenced and queried against published microsporidial genomes. DNA sequences shared 98.2-99.8% sequence identity to Clade III of the Marinosporidia. This is the first report of a microsporidial infection contributing to the mortality of a sea turtle.


Assuntos
Microsporídios não Classificados/genética , Microsporídios não Classificados/ultraestrutura , Microsporidiose/veterinária , Filogenia , Tartarugas/microbiologia , Animais , DNA Fúngico/genética , Feminino , Microsporidiose/microbiologia , Músculo Esquelético/patologia , RNA Fúngico/genética , RNA Ribossômico/genética
3.
J Invertebr Pathol ; 143: 124-134, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27993617

RESUMO

Parahepatospora carcini n. gen. n. sp., is a novel microsporidian parasite discovered infecting the cytoplasm of epithelial cells of the hepatopancreas of a single Carcinus maenas specimen. The crab was sampled from within its invasive range in Atlantic Canada (Nova Scotia). Histopathology and transmission electron microscopy were used to show the development of the parasite within a simple interfacial membrane, culminating in the formation of unikaryotic spores with 5-6 turns of an isofilar polar filament. Formation of a multinucleate meront (>12 nuclei observed) preceded thickening and invagination of the plasmodial membrane, and in many cases, formation of spore extrusion precursors (polar filaments, anchoring disk) prior to complete separation of pre-sporoblasts from the sporogonial plasmodium. This developmental feature is intermediate between the Enterocytozoonidae (formation of spore extrusion precursors within the sporont plasmodium) and all other Microsporidia (formation of spore extrusion precursors after separation of sporont from the sporont plasmodium). SSU rRNA-based gene phylogenies place P. carcini within microsporidian Clade IV, between the Enterocytozoonidae and the so-called Enterocytospora-clade, which includes Enterocytospora artemiae and Globulispora mitoportans. Both of these groups contain gut-infecting microsporidians of aquatic invertebrates, fish and humans. According to morphological and phylogenetic characters, we propose that P. carcini occupies a basal position to the Enterocytozoonidae. We discuss the discovery of this parasite from a taxonomic perspective and consider its origins and presence within a high profile invasive host on the Atlantic Canadian coastline.


Assuntos
Braquiúros/parasitologia , Microsporídios não Classificados/classificação , Microsporídios não Classificados/genética , Animais , Microscopia Eletrônica de Transmissão , Microsporídios não Classificados/ultraestrutura , Filogenia , Reação em Cadeia da Polimerase
4.
Parasitol Res ; 116(2): 773-780, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27987055

RESUMO

This study describes a new genus and species of microsporidia which is a pathogen of the elm leaf beetle, Xanthogaleruca luteola Muller, 1776 (Coleoptera: Chrysomelidae). The beetles were collected from Istanbul in Turkey. All developmental stages are uninucleate and in direct contact with the host cell cytoplasm. Giemsa-stained mature spores are oval in shape and measured 3.40 ± 0.37 µm in length and 1.63 ± 0.20 µm in width. These uninucleate spores have an isofilar polar filament with 11 turns. The spore wall was trilaminar (75 to 115 nm) with a rugose, electron-dense exospore (34 to 45 nm) and a thickened, electron-lucent endospore (65 to 80 nm) overlaying the plasmalemma. Morphological, ultrastructural, and molecular features indicate that the described microsporidium is dissimilar to all known microsporidian taxa and confirm that it has different taxonomic characters than other microsporidia infecting X. luteola and is named here as Rugispora istanbulensis n. gen., n. sp.


Assuntos
Besouros/microbiologia , Microsporídios não Classificados/classificação , Animais , Microsporídios não Classificados/genética , Microsporídios não Classificados/isolamento & purificação , Microsporídios não Classificados/ultraestrutura , Filogenia , Folhas de Planta/parasitologia , Análise de Sequência de DNA , Esporos Fúngicos , Turquia , Ulmus/parasitologia
5.
J Invertebr Pathol ; 135: 43-52, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26853837

RESUMO

The microsporidian parasite Globulispora mitoportans, n. g., n. sp., infects the intestinal epithelium of two species of daphnids (Crustacea: Cladocera). Mature spores are thin-walled and possess a novel type of polaroplast with a conspicuous part consisting of globules that occupies a large part of the spore volume. Both developmental stages and the spores possess large, electron-lucent vesicles enveloped by a double membrane and filled with an internal web of filamentous material, corresponding structurally to microsporidian mitosomes. The SSU rRNA phylogeny places Globulispora into a specific "Enterocytospora-like" clade, part of a large "non-enterocytozoonidae" clade, grouping a heterogenous assemblage of microsporidia infecting almost exclusively insects and crustacea.


Assuntos
Daphnia/parasitologia , Microsporídios não Classificados/classificação , Animais , Núcleo Celular/ultraestrutura , DNA Fúngico/química , DNA Fúngico/isolamento & purificação , DNA Ribossômico/química , Funções Verossimilhança , Microscopia Eletrônica de Transmissão , Microsporídios não Classificados/genética , Microsporídios não Classificados/ultraestrutura , Filogenia , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Esporos Fúngicos/ultraestrutura
6.
J Eukaryot Microbiol ; 63(3): 318-25, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26567000

RESUMO

The microsporidium, Anncaliia algerae (Brachiola algerae), is a eukaryotic obligate intracellular parasite first isolated from mosquitoes and is an important opportunistic human pathogen that can cause morbidity and mortality among immune-compromised individuals including patients with AIDS and those undergoing chemotherapy. There is little known about the Microsporidia-host cell interface in living host cells, due to current approaches being limited by the lack of fluorescent reporters for detecting the parasite lifecycle. Here, we have developed and applied novel vital fluorescent parasite labeling methodologies in conjunction with fluorescent protein-tagged reporters to track simultaneously the dynamics of both parasite and host cell specific components, including the secretory and endocytic trafficking pathways, during the entire infection time period. We have found dramatic changes in the dynamics of host secretory trafficking organelles during the course of infection. The Golgi compartment is gradually disassembled and regenerated into mini-Golgi structures in parallel with cellular microtubule depolymerization. Importantly, we find that Microsporidia progeny are associated with these de novo formed mini-Golgi structures. These host structures appear to create a membrane bound niche environment for parasite development. Our studies presented here provide novel imaging tools and methodologies that will facilitate in understanding the biology of microsporidial parasites in the living host.


Assuntos
Microsporídios não Classificados/crescimento & desenvolvimento , Microsporídios não Classificados/ultraestrutura , Análise Espaço-Temporal , Coloração e Rotulagem/métodos , Complexo de Golgi/parasitologia , Complexo de Golgi/ultraestrutura , Células HeLa , Interações Hospedeiro-Parasita , Humanos , Estágios do Ciclo de Vida , Microscopia Confocal , Microscopia de Fluorescência/métodos , Microsporídios não Classificados/fisiologia , Microtúbulos/microbiologia , Esporos Fúngicos/ultraestrutura , Vesículas Transportadoras/microbiologia
7.
J Invertebr Pathol ; 126: 31-42, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25637516

RESUMO

An undescribed microsporidium was detected and isolated from the South American bumble bee Bombus atratus collected in the Pampas region of Argentina. Infection intensity in workers averaged 8.2 × 10(7)spores/bee. The main site of infection was adipose tissue where hypertrophy of adipocytes resulted in cyst-like body formation. Mature spores were ovoid and monomorphic. They measured 4.00 µm × 2.37 µm (fresh) or 3.98 µm × 1.88 µm (fixed). All stages were diplokariotic and developed in direct contact with host cytoplasm. Isofilar polar filament was arranged in 16 coils in one or, posteriorly, two layers. Coiling angle was variable, between perpendicular and almost parallel to major spore axis. Late meronts and sporogonial stages were surrounded by vesicles of approximately 60 nm in diameter. Based on both new and already designed primers, a 1827 bp (SSUrRNA, ITS, LSUrRNA) sequence was obtained. Data analyses suggest that this microsporidium is a new species of the genus Tubulinosema. The name Tubulinosema pampeana sp. n. is proposed.


Assuntos
Abelhas/microbiologia , Interações Hospedeiro-Patógeno , Microsporídios não Classificados/fisiologia , Animais , Argentina , Abelhas/ultraestrutura , Citoplasma/microbiologia , Feminino , Funções Verossimilhança , Masculino , Microscopia Eletrônica de Transmissão , Microsporídios não Classificados/isolamento & purificação , Microsporídios não Classificados/ultraestrutura , Filogenia , Esporos Fúngicos/ultraestrutura
8.
J Eukaryot Microbiol ; 62(1): 60-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25105446

RESUMO

The Microsporidium, Anncaliia algerae, an obligate intracellular parasite, has been identified as an opportunistic human pathogen, but treatment has not been evaluated for infections with this organism. Albendazole, an antitubulin polymerization drug used against parasitic worm infections, has been the medication of choice used to treat some microsporidial infections affecting humans, with varying results ranging from clearing infection (Encephalitozoon) to resistance (Enterocytozoon). This study illustrates the effect of albendazole treatment on A. algerae infection in Rabbit Kidney (RK13) cells and Human Fetal Lung (HFL-1) fibroblasts. Albendazole appears to have an attenuating effect on A. algerae infection and albendazole's IC50 in RK13 cells is 0.1 µg/ml. Long-term treatment inhibits up to 98% of spore production, but interrupting treatment reestablishes the infection without new exposure to the parasite as supported by microscopic observations. The parasite's beta-tubulin gene was purified, cloned, and sequenced. Five of the six specific amino acids, associated with benzimidazole sensitivity, are conserved in A. algerae. These findings suggest that A. algerae is sensitive to albendazole; however, the organism is not completely cleared from cultures.


Assuntos
Proteínas Fúngicas/genética , Microsporídios não Classificados/efeitos dos fármacos , Esporos Fúngicos/efeitos dos fármacos , Moduladores de Tubulina/farmacologia , Tubulina (Proteína)/genética , Albendazol/farmacologia , Sequência de Aminoácidos , Animais , Benzimidazóis/farmacologia , Linhagem Celular , Clonagem Molecular , Sequência Conservada , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/microbiologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/microbiologia , Proteínas Fúngicas/metabolismo , Expressão Gênica , Humanos , Rim , Pulmão , Testes de Sensibilidade Microbiana , Microsporídios não Classificados/genética , Microsporídios não Classificados/metabolismo , Microsporídios não Classificados/ultraestrutura , Dados de Sequência Molecular , Coelhos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Esporos Fúngicos/genética , Esporos Fúngicos/metabolismo , Esporos Fúngicos/ultraestrutura , Tubulina (Proteína)/metabolismo
9.
J Eukaryot Microbiol ; 60(2): 166-78, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23316714

RESUMO

This study provides evidence for the Golgi-like activity of the multilayered interlaced network (MIN) and new ultrastructural observations of the MIN in the sporoplasm of Anncaliia algerae, a microsporidium that infects both insects and humans. The MIN is attached to the end of the polar tubule upon extrusion from the germinating spore. It surrounds the sporoplasm, immediately below its plasma membrane, and most likely maintains the integrity of the sporoplasm, as it is pulled through the everting polar tube. Furthermore, the MIN appears to deposit its dense contents on the surface of the sporoplasm within minutes of spore discharge thickening the plasma membrane. This thickening is characteristic of the developmental stages of the genus Anncaliia. The current study utilizes transmission electron microscopy (TEM), enzyme histochemistry, and high voltage TEM (HVEM) with 3D tomographic reconstruction to both visualize the structure of the MIN and demonstrate that the MIN is a Golgi-related structure. The presence of developmentally regulated Golgi in the Microsporidia has been previously documented. The current study extends our understanding of the microsporidial Golgi and is consistent with the MIN being involved in the extracellular secretion in Anncaliia algerae. This report further illustrates the unique morphology of the MIN as illustrated by HVEM using 3D tomography.


Assuntos
Citoplasma/ultraestrutura , Complexo de Golgi/ultraestrutura , Microsporídios não Classificados/ultraestrutura , Esporos Fúngicos/ultraestrutura , Tomografia com Microscopia Eletrônica , Imageamento Tridimensional , Microscopia Eletrônica de Transmissão
10.
Parasitol Res ; 110(3): 1201-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21863399

RESUMO

The description of Helmichia lacustris Voronin (Parazitologiya 34:327-331 1998) is supplemented with morphogenesis and ultrastructure of the extrusion apparatus. Formation of the anterior (made up by rare short lamellae) and posterior (made up by spongy matter or small vesicles) regions of the polaroplast is preceded by granulated spheres and agglomerations of bean-like bodies, respectively. The anchoring disc is formed by an oval structure of moderate electron density, sometimes possessing a granular texture. The parasite development occurs within the cisterns of granular endoplasmatic reticulum (ER) of the host cell. Each group of spores is enclosed within a two-layered sheath, including the smooth inner membrane of the sporophorous vesicle and the outer ribosome-encrusted membrane (which originates from the host cell ER) of the parasitophorous vacuole. Two microsporidia, H. lacustris (GenBank accession number GU130406) and Euplotespora binucleata (GenBank accession number DQ675604) share 78.1% of 16S rRNA gene sequence similarity. Both parasites are characterized by an uncoiled isofilar polar filament. They form a cluster nested among terrestrial and aquatic microsporidia with well-developed coiled polar filaments, suggesting that an uncoiled polar filament in this species is a result of reduction, rather than a "primitive" character.


Assuntos
Chironomidae/parasitologia , Microsporídios não Classificados/genética , Microsporídios não Classificados/ultraestrutura , Organelas/ultraestrutura , Filogenia , Animais , Chironomidae/crescimento & desenvolvimento , DNA Fúngico/genética , DNA Ribossômico/genética , Larva/parasitologia , Microscopia Eletrônica de Transmissão , Microsporídios não Classificados/isolamento & purificação , Microsporídios não Classificados/fisiologia , Dados de Sequência Molecular , Análise de Sequência de DNA , Esporos Fúngicos/ultraestrutura
11.
J Invertebr Pathol ; 106(2): 280-8, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21056570

RESUMO

Hippodamia convergens, the convergent lady beetle, is available for aphid control in home gardens and in commercial food production systems throughout the United States and Canada. Beetles received from commercial insectaries for biological control are occasionally infected with a microsporidium. The objective of this study was to describe the pathogen by means of ultrastructure, molecular characterization and tissue pathology. All stages of the microsporidium were in direct contact with the host cell cytoplasm. Early developmental stages were proximal to mature spores and both were observed throughout the tissue sections that were examined. Merogony resulted from binary fission. Early-stage sporoblasts were surrounded by a highly convoluted plasma membrane and contained an electron-dense cytoplasm and diplokaryon. Ovoid to elongated late-stage sporoblasts were surrounded by a relatively complete spore wall. The polar filament, polaroplast, and anchoring disk were readily observed within the cell cytoplasm. Mature spores were typical of terrestrial microsporidia, with a thickened endospore surrounded by a thin exospore. Spores contained well-defined internal structures, including a diplokaryon, lamellar polaroplast and a slightly anisofilar polar filament with 10-14 coils arranged in a single or double row. A prominent indentation was evident at the apical end of the spore wall proximal to the anchoring disk. Aberrant spores were also observed. These had a fully developed endospore and exospore but lacked any discernable internal spore structures, and were, instead, filled with lamellar or vesicular structures. Typical and aberrant spores measured 3.58 ± 0.2 × 2.06 ± 0.2 µm (n=10) and 3.38 ± 0.8 × 2.13 ± 0.2 µm (n=10), respectively. Spores were observed in longitudinal muscle surrounding the midgut and within the fat body, Malpighian tubules, pyloric valve epithelium, ventral nerve cord ganglia, muscles and ovaries. The hindgut epithelium was often infected but the connective tissues were rarely invaded. The life cycle and pathology of the microsporidium bears some resemblance to Nosema hippodamiae, the only microsporidium reported from H. convergens by Lipa and Steinhaus in 1959. Molecular characterization of the pathogen genomic DNA revealed that it is 99% similar to Tubulinosema acridophagus and T. ratisbonensis, two pathogens that infect Drosophila melanogaster and 98% similar to T. kingi from D. willistoni. Based on similarities in pathogen ultrastructure and the molecular information gained during this study, we propose that the microsporidium in H. convergens be given the name Tubulinosema hippodamiae.


Assuntos
Besouros/microbiologia , Microsporídios não Classificados/ultraestrutura , Animais , Besouros/citologia , Citoplasma/microbiologia , Citoplasma/ultraestrutura , Estruturas Citoplasmáticas/microbiologia , Estruturas Citoplasmáticas/ultraestrutura , Feminino , Gânglios/microbiologia , Masculino , Túbulos de Malpighi/microbiologia , Microsporídios não Classificados/patogenicidade , Músculos/microbiologia , Especificidade da Espécie , Terminologia como Assunto
12.
J Eukaryot Microbiol ; 57(6): 562-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20958855

RESUMO

We describe a biopsy proven case of microsporidial infection of the false vocal cords in a 69-yr-old male with a history of chronic lymphocytic leukemia. The patient had hoarseness for several weeks before his admission to the hospital for shortness of breath. He had received chemotherapy with fludarabine 6 wk before this hospital admission. A biopsy of vocal cord nodules demonstrated an organism that was identified as Anncaliia algerae by electron microscopy. Molecular analysis of the small subunit RNA gene amplified by polymerase chain reaction further confirmed the identification of this organism as A. algerae. This case illustrates the ability of this insect pathogen to cause disease in immune-compromised mammalian hosts.


Assuntos
Laringite/diagnóstico , Microsporídios não Classificados/isolamento & purificação , Microsporidiose/diagnóstico , Prega Vocal/patologia , Idoso , Biópsia , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Humanos , Laringite/microbiologia , Leucemia Linfocítica Crônica de Células B/complicações , Masculino , Microscopia Eletrônica , Microsporídios não Classificados/classificação , Microsporídios não Classificados/ultraestrutura , Microsporidiose/microbiologia , Dados de Sequência Molecular , Micologia/métodos , Filogenia , Análise de Sequência de DNA , Prega Vocal/microbiologia
13.
Parasitol Res ; 107(6): 1381-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20697911

RESUMO

The life cycle, ultrastructure, and molecular phylogeny of a new microsporidium Crispospora chironomi g.n. sp.n., a parasite of the midge Chironomus plumosus, are described. The parasite infects the gut epithelium of the host larvae and possesses sporogonies of two types, polysporoblastic and disporoblastic, respectively, proceeding within the same host cell. In the sporogonial sequence of the first type, dozens of spherical monokaryotic spores within a thick-walled capsule are formed. The spores are 1.5-2.0 µm in diameter; the exospore possesses two to three bundles of tubular protrusions. In the sporogonial sequence of the second type, diplokaryotic oval spores, 2.5 × 1.5 µm in size, are formed within a compartment, partially surrounded with multilayered membranes. Spores of both types are similar in respect to inner structure, possessing a well-developed extrusion apparatus with (a) the anterior vesicular part of the polaroplast covering the lamellar posterior one and (b) isofilar polar filament with several coils in one row. Small subunit ribosomal DNA phylogeny showed position of the new microsporidium in a cluster uniting microsporidia of terrestrial origin infecting diverse hosts, nested within Clade IV, corresponding to Class Terresporidia sensu Vossbrinck and Debrunner-Vossbrinck (Folia Parasitol 52:131-142, 2005).


Assuntos
Chironomidae/microbiologia , Microsporídios não Classificados/classificação , Microsporídios não Classificados/ultraestrutura , Animais , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Genes de RNAr , Mucosa Intestinal/microbiologia , Estágios do Ciclo de Vida , Microsporídios não Classificados/genética , Microsporídios não Classificados/crescimento & desenvolvimento , Dados de Sequência Molecular , Filogenia , RNA Fúngico/genética , RNA Ribossômico 18S/genética , Análise de Sequência de DNA , Esporos Fúngicos/ultraestrutura
14.
Parasitol Res ; 107(1): 39-46, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20372928

RESUMO

Larvae of Chironomus plumosus, collected in North-Western Russia in September 2008, were infected with a microsporidium possessing broadly oval uninucleate spores in sporophorous vesicles. Sporogony and spore ultrastructure of this microsporidium differed from that of known microsporidian species, suggesting establishment of a new species, Anisofilariata chironomi, being a type species of a new genus. Sporogony di-, tetra-, octo-, and 16-sporoblastic. Fixed and stained spores are 4.7-6.8 x 3.4-5.4 microm in size, the spore measurements varying depending upon the number of spores in the sporophorous vesicle. The polaroplast is bipartite, with anterior and posterior parts composed of very thin and thick lamellae, respectively, and occupies the major volume of the spore. The polar filament is anisofilar, with two broad proximal and 10-13 narrow distal coils arranged in 2-4 layers. The sporophorous vesicle is bounded by a thin membrane and contains multiple tubular structures. Small subunit ribosomal DNA phylogeny showed basal position of the new microsporidium to a cluster uniting microsporidia infecting ciliates (Euplotespora binucleata), microcrustaceans (Glugoides intestinalis, Mrazekia macrocyclopis), lepidopteran insects (Cystosporogenes spp., Endoreticulatus spp.) and human (Vittaforma corneae), nested within Clade IV sensu Vossbrinck and Debrunner-Vossbrinck (2005 Folia Parasitol 52:131-142). No close phylogenetic relationships were found between A. chironomi and microsporidia from other dipteran hosts.


Assuntos
Chironomidae/microbiologia , Microsporídios não Classificados/classificação , Microsporídios não Classificados/ultraestrutura , Filogenia , Animais , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Genes de RNAr , Microscopia , Microscopia Eletrônica de Transmissão , Microsporídios não Classificados/genética , Microsporídios não Classificados/isolamento & purificação , Dados de Sequência Molecular , Organelas/ultraestrutura , RNA Fúngico/genética , RNA Ribossômico 18S/genética , Federação Russa , Análise de Sequência de DNA , Esporos Fúngicos/ultraestrutura
15.
Parasitology ; 135(8): 903-29, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18598575

RESUMO

Thelohania solenopsae is a unique microsporidium with a life-cycle finely tuned to parasitizing fire ant colonies. Unlike other microsporidia of social hymenopterans, T. solenopsae infects all castes and stages of the host. Four distinctive spore types are produced: diplokaryotic spores, which develop only in brood (Type 1 DK spores); octets of octospores within sporophorous vesicles, the most prominent spore type in adults but never occurring in brood; Nosema-like diplokaryotic spores (Type 2 DK spores) developing in adults; and megaspores, which occur occasionally in larvae 4, pupae, and adults of all castes but predominantly infect gonads of alates and germinate in inseminated ovaries of queens. Type 2 DK spores function in autoinfection of adipocytes. Proliferation of diplokaryotic meronts in some cells is followed by karyogamy of diplokarya counterparts and meiosis, thereby switching the diplokaryotic sequence to octospore or megaspore development. Megaspores transmit the pathogen transovarially. From the egg to larvae 4, infection is inapparent and can be detected only by PCR. Type 1 DK spore and megaspore sequences are abruptly triggered in larvae 4, the key stage in intra-colony food distribution via trophallaxis, and presumably the central player in horizontal transmission of spores. Molecular, morphological, ultrastructural and life-cycle data indicate that T. solenopsae must be assigned to a new genus. We propose a new combination, Kneallhazia solenopsae.


Assuntos
Formigas/parasitologia , Estágios do Ciclo de Vida/fisiologia , Microsporídios não Classificados/classificação , Microsporídios não Classificados/crescimento & desenvolvimento , Animais , DNA Ribossômico/genética , Feminino , Larva/parasitologia , Microscopia Eletrônica de Transmissão , Microsporídios não Classificados/citologia , Microsporídios não Classificados/ultraestrutura , Ovário/parasitologia , Filogenia , Pupa/parasitologia , Esporos de Protozoários/citologia , Esporos de Protozoários/ultraestrutura
16.
J Parasitol ; 93(3): 655-60, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17626360

RESUMO

A previously unrecognized microsporidian (Kabatana newberryi n. sp.) is described from the musculature of Eucyclogobius newberryi (Gobiidae) in Big Lagoon, Humboldt County, California. Spores are ovoid, ranging in size from 2.8 +/- 0.3 microm in total length and 1.9 +/- 0.4 microm in width (measurements of 30 spores made by calculation from micrograph). The polar filament has 9-10 coils in 1-2 rows. Development occurs in direct contact with host muscle cell cytoplasm, without xenoma or sporophorous vesicle. Phylogenetic analysis of the new species and of 35 other microsporidians known to infect fish using 1115 base pairs of aligned 16S rRNA gene indicate the new species is most closely related to Kabatana takedai. However, the new species differs by 11% sequence divergence from K. takedai. Divergence in morphology and genetic data allow for diagnosis from all other fish-infecting microsporidia and supports recognition of a new species of microsporidian, Kabatana newberryi n. sp., presently known only from a suspected specific host, the endangered tidewater goby Eucyclogobius newberryi.


Assuntos
Doenças dos Peixes/parasitologia , Microsporídios não Classificados/classificação , Microsporidiose/veterinária , Perciformes/parasitologia , Animais , California , DNA Fúngico/química , DNA Ribossômico/química , Microscopia Eletrônica de Transmissão/veterinária , Microsporídios não Classificados/genética , Microsporídios não Classificados/crescimento & desenvolvimento , Microsporídios não Classificados/ultraestrutura , Microsporidiose/parasitologia , Músculos/microbiologia , Músculos/ultraestrutura , Filogenia , Reação em Cadeia da Polimerase/veterinária , RNA Fúngico/genética , RNA Ribossômico 16S/genética
17.
Folia Parasitol (Praha) ; 54(4): 259-71, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18303767

RESUMO

A brief nomenclatural history of Vavraia culicis (Weiser, 1947), the type species for the genus Vavraia Weiser, 1977, is presented together with a detailed description of the cytological and ultrastructural characteristics of a Vavraia culicis-like microsporidian species isolated from Aedes albopictus (Scuse) in Florida. This "Florida isolate", is the only known isolate of a species of the genus Vavraia from mosquitoes propagated in laboratory culture. Although the Florida isolate has been used under the name Vavraia culicis in several molecular phylogeny and host-parasite studies, it has not been structurally characterized and its relationship to the type species Vavraia culicis has never been examined. Structural data strongly support placement of the Florida isolate within the genus Vavraia and indicate its close relationship to both the type species of the genus and to other Vavraia-like mosquito microsporidia to which the name V. culicis has been applied. However, the identity of the Florida isolate with V. culicis (Weiser, 1947) Weiser, 1977 cannot be presently confirmed. Morphometric examination of spores of several Vavraia-like microsporidia isolates from mosquitoes, including the type material of Vavraia culicis, indicates that Vavraia culicis-like microsporidia probably represent not a single species, but a group of closely related organisms. Subspecies status is proposed for the Florida isolate.


Assuntos
Microsporídios não Classificados/classificação , Microsporídios não Classificados/ultraestrutura , Aedes/microbiologia , Animais , Florida , Microscopia Eletrônica de Transmissão , Especificidade da Espécie , Esporos Fúngicos/ultraestrutura
18.
J Invertebr Pathol ; 91(3): 168-82, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16524588

RESUMO

A new microsporidium, Liebermannia patagonica n. gen., n. sp., is described from midgut and gastric caecum epithelial cells of Tristira magellanica, an apterous grasshopper species of southern Patagonia, Argentina. L.patagonica is diplokaryotic, apansporoblastic, homosporous, and polysporoblastic. Transitional (from merogony to sporogony) stages and sporonts of L. patagonica were surrounded by host rough endoplasmic reticulum. The ovocylindrical spores measured 2.9 +/- 0.09 x 1.2 +/- 0.04 microm (fresh, n = 50), and they had an isofilar polar filament of only three coils and a cluster of tubules instead of a classical posterior vacuole. Prevalence was high (up to 80.6%) at the type locality for the four years sampled . Maximum likelihood , neighbor joining, maximum parismony analyses of the small submit rDNA all placed L.patagonica(Accession No. DQ 239917) in one with Orthosomella operophterae.


Assuntos
Gafanhotos/parasitologia , Microsporídios não Classificados/genética , Microsporídios não Classificados/ultraestrutura , Esporos de Protozoários/genética , Esporos de Protozoários/ultraestrutura , Animais , DNA Ribossômico , Interações Hospedeiro-Parasita , Microscopia Eletrônica de Transmissão , Microsporídios não Classificados/classificação , Microsporídios não Classificados/crescimento & desenvolvimento , Microsporídios não Classificados/isolamento & purificação , Microsporídios não Classificados/fisiologia , Dados de Sequência Molecular , Filogenia , Esporos de Protozoários/fisiologia , Tropismo
19.
J Eukaryot Microbiol ; 52(6): 476-83, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16313438

RESUMO

A new species of Microsporidia classified to a new genus was observed in the trunk muscle of commercial hake (Merluccius capensis/paradoxus complex) from Namibian fisheries. Macroscopic examination revealed thin and dark filaments inserted among muscle fibers. Inside the filaments were many sporophorous vesicles with about 30-50 spores per vesicle. The shape of the spore was pyriform and the extruded polar filament was of moderate length (up to 4.29 microm, n=12). This new species of Microsporidia is described using macrophotography, microphotography, staining, and transmission electron microscopy (TEM), as well as molecular methods. Its 16S rRNA was found to be similar to that of Microsporidium prosopium Kent et al., 1999, while both sequences were quite different from 16S rRNA sequences known for other Microsporidia. Nevertheless, this new species is separated morphologically from M. prosopium by the presence of 11-12 anisofilar coils and the formation of the xenoma at the site of infection. Type species.


Assuntos
Doenças dos Peixes/microbiologia , Pesqueiros , Gadiformes/microbiologia , Microsporídios não Classificados/classificação , Microsporídios não Classificados/isolamento & purificação , Microsporídios não Classificados/ultraestrutura , Microsporidiose/veterinária , Músculos/microbiologia , Animais , DNA Fúngico/análise , DNA Ribossômico/análise , Microscopia Eletrônica de Transmissão , Microsporídios não Classificados/genética , Dados de Sequência Molecular , Técnicas de Tipagem Micológica , Namíbia , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
20.
J Invertebr Pathol ; 83(3): 240-8, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12877831

RESUMO

We have isolated a microsporidium from a laboratory stock of the European grape vine moth, Lobesia botrana Den. et Schiff. (Lepidoptera, Tortricidae). Screening of this stock showed an infection rate of more than 90%, whereas field collected larvae from three different locations in Rhineland-Palatinate (Germany) did not demonstrate any signs of infection. Light and electron microscopic investigations of infected insects showed that gross pathology, morphology, and ultrastructure of the microsporidium are similar to those described earlier for Pleistophora legeri. Comparative phylogenetic analysis of the small subunit rDNA using maximum likelihood, maximum parsimony, and neighbour joining distance methods showed that our isolate was closely related to Cystosporogenes operophterae. Based on our morphological and molecular investigations we propose to rename this species Cystosporogenes legeri nov. comb.


Assuntos
DNA de Protozoário/análise , Microsporídios não Classificados/classificação , Microsporidiose , Mariposas/parasitologia , Homologia de Sequência do Ácido Nucleico , Animais , Sequência de Bases , DNA Ribossômico/análise , Microscopia Eletrônica , Microsporídios não Classificados/patogenicidade , Microsporídios não Classificados/fisiologia , Microsporídios não Classificados/ultraestrutura , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
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