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McKinley K, Tsaousis AD, Rückert S. Description and prevalence of gregarines infecting the amphipod Gammarus pulex, in the Water of Leith, Scotland, UK. Eur J Protistol 2024; 94:126084. [PMID: 38692224 DOI: 10.1016/j.ejop.2024.126084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 04/14/2024] [Accepted: 04/17/2024] [Indexed: 05/03/2024]
Abstract
Gregarines are symbiotic protists that are found in a broad spectrum of invertebrates, including insects, crustaceans, and annelids. Among these the globally distributed amphipod Gammarus pulex is one of the earliest recognized hosts for aquatic gregarines and is prevalent among macroinvertebrates in freshwater environments. In this study, samples of G. pulex were collected in the Water of Leith river, Scotland, UK. Gregarines were identified using light and scanning electron microscopy as well as standard molecular techniques. We identified three septate eugregarine symbionts-Heliospora longissima, Cephaloidophora gammari, and the here newly characterized Cephaloidophora conus n. sp. (formerly Cephaloidophora sp.) associated with Gammarus pulex in the Water of Leith. Prevalences for identified gregarine species were calculated and seasonal dynamics of gregarine infections/colonization were analyzed. Prevalences were highest in autumn and spring reaching almost 50 %. While the two Cephaloidophora species showed similar colonization patterns, the prevalence of Heliospora showed an opposite trend. Identifying gregarine infection/colonization patterns is one step towards better understanding the gregarine-host relationship, as well as possible impacts of the gregarines on their hosts.
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Affiliation(s)
- Kevin McKinley
- School of Applied Sciences, Edinburgh Napier University, Edinburgh, Scotland, UK; Laboratory of Molecular and Evolutionary Parasitology, RAPID Group, School of Biosciences, University of Kent, Canterbury, Kent, England, UK; Centre for Conservation and Restoration Science, School of Applied Sciences, Edinburgh Napier University, Edinburgh, Scotland, UK
| | - Anastasios D Tsaousis
- Laboratory of Molecular and Evolutionary Parasitology, RAPID Group, School of Biosciences, University of Kent, Canterbury, Kent, England, UK
| | - Sonja Rückert
- Department of Eukaryotic Microbiology, Faculty of Biology, University of Duisburg-Essen, Essen, Germany; Centre for Conservation and Restoration Science, School of Applied Sciences, Edinburgh Napier University, Edinburgh, Scotland, UK.
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de Albuquerque NRM, Haag KL. Using average nucleotide identity (ANI) to evaluate microsporidia species boundaries based on their genetic relatedness. J Eukaryot Microbiol 2023; 70:e12944. [PMID: 36039868 DOI: 10.1111/jeu.12944] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 08/26/2022] [Accepted: 08/27/2022] [Indexed: 11/28/2022]
Abstract
Microsporidia are obligatory intracellular parasites related to fungi and since their discovery their classification and origin has been controversial due to their unique morphology. Early taxonomic studies of microsporidia were based on ultrastructural spore features, characteristics of their life cycle and transmission modes. However, taxonomy and phylogeny based solely on these characteristics can be misleading. SSU rRNA is a traditional marker used in taxonomical classifications, but the power of SSU rRNA to resolve phylogenetic relationships between microsporidia is considered weak at the species level, as it may not show enough variation to distinguish closely related species. Overall genome relatedness indices (OGRI), such as average nucleotide identity (ANI), allows fast and easy-to-implement comparative measurements between genomes to assess species boundaries in prokaryotes, with a 95% cutoff value for grouping genomes of the same species. Due to the increasing availability of complete genomes, metrics of genome relatedness have been applied for eukaryotic microbes taxonomy such as microsporidia. However, the distribution of ANI values and cutoff values for species delimitation have not yet been fully tested in microsporidia. In this study we examined the distribution of ANI values for 65 publicly available microsporidian genomes and tested whether the 95% cutoff value is a good estimation for circumscribing species based on their genetic relatedness.
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Affiliation(s)
- Nathalia R M de Albuquerque
- Department of Genetics and Post-Graduation Program of Genetics and Molecular Biology, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Karen L Haag
- Department of Genetics and Post-Graduation Program of Genetics and Molecular Biology, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
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3
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Frolova EV, Paskerova GG, Smirnov AV, Nassonova ES. Diversity, Distribution, and Development of Hyperparasitic Microsporidia in Gregarines within One Super-Host. Microorganisms 2023; 11:microorganisms11010152. [PMID: 36677444 PMCID: PMC9864637 DOI: 10.3390/microorganisms11010152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 12/26/2022] [Accepted: 12/29/2022] [Indexed: 01/11/2023] Open
Abstract
Metchnikovellids (Microsporidia: Metchnikovellida) are poorly studied hyperparasitic microsporidia that live in gregarines inhabiting the intestines of marine invertebrates, mostly polychaetes. Our recent studies showed that diversity of metchnikovellids might be significantly higher than previously thought, even within a single host. Four species of metchnikovellids were found in the gregarines inhabiting the gut of the polychaete Pygospio elegans from littoral populations of the White and Barents Seas: the eugregarine Polyrhabdina pygospionis is the host for Metchnikovella incurvata and M. spiralis, while the archigregarine Selenidium pygospionis is the host for M. dogieli and M. dobrovolskiji. The most common species in the White Sea is M. incurvata, while M. dobrovolskiji prevails in the Barents Sea. Gregarines within a single worm could be infected with different metchnikovellid species. However, co-infection of one and the same gregarine with several species of metchnikovellids has never been observed. The difference in prevalence and intensity of metchnikovellid invasion apparently depends on the features of the life cycle and on the development strategies of individual species.
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Affiliation(s)
- Ekaterina V. Frolova
- Laboratory of Cytology of Unicellular Organisms, Institute of Cytology of Russian Academy of Sciences, Tikhoretsky Ave. 4, 194064 St. Petersburg, Russia
- Department of Invertebrate Zoology, Faculty of Biology, St Petersburg University, Universitetskaya Emb. 7/9, 199034 St. Petersburg, Russia
| | - Gita G. Paskerova
- Department of Invertebrate Zoology, Faculty of Biology, St Petersburg University, Universitetskaya Emb. 7/9, 199034 St. Petersburg, Russia
| | - Alexey V. Smirnov
- Department of Invertebrate Zoology, Faculty of Biology, St Petersburg University, Universitetskaya Emb. 7/9, 199034 St. Petersburg, Russia
| | - Elena S. Nassonova
- Laboratory of Cytology of Unicellular Organisms, Institute of Cytology of Russian Academy of Sciences, Tikhoretsky Ave. 4, 194064 St. Petersburg, Russia
- Correspondence:
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Abstract
Around 57.1% of microsporidia occupy aquatic environments, excluding a further 25.7% that utilise both terrestrial and aquatic systems. The aquatic microsporidia therefore compose the most diverse elements of the Microsporidia phylum, boasting unique structural features, variable transmission pathways, and significant ecological influence. From deep oceans to tropical rivers, these parasites are present in most aquatic environments and have been shown to infect hosts from across the Protozoa and Animalia. The consequences of infection range from mortality to intricate behavioural change, and their presence in aquatic communities often alters the overall functioning of the ecosystem.In this chapter, we explore aquatic microsporidian diversity from the perspective of aquatic animal health. Examples of microsporidian parasitism of importance to an aquacultural ('One Health') context and ecosystem context are focussed upon. These include infection of commercially important penaeid shrimp by Enterocytozoon hepatopenaei and interesting hyperparasitic microsporidians of wild host groups.Out of ~1500 suggested microsporidian species, 202 have been adequately taxonomically described using a combination of ultrastructural and genetic techniques from aquatic and semi-aquatic hosts. These species are our primary focus, and we suggest that the remaining diversity have additional genetic or morphological data collected to formalise their underlying systematics.
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Affiliation(s)
- Jamie Bojko
- School of Health and Life Sciences, Teesside University, Middlesbrough, UK.
- National Horizons Centre, Teesside University, Darlington, UK.
| | - Grant D Stentiford
- Centre for Environment, Fisheries and Aquaculture Science, Weymouth, Dorset, UK
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5
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Paskerova GG, Miroliubova TS, Valigurová A, Janouškovec J, Kováčiková M, Diakin A, Sokolova YY, Mikhailov KV, Aleoshin VV, Simdyanov TG. Evidence from the resurrected family Polyrhabdinidae Kamm, 1922 (Apicomplexa: Gregarinomorpha) supports the epimerite, an attachment organelle, as a major eugregarine innovation. PeerJ 2021; 9:e11912. [PMID: 34616591 PMCID: PMC8450007 DOI: 10.7717/peerj.11912] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 07/14/2021] [Indexed: 11/21/2022] Open
Abstract
Background Gregarines are a major group of apicomplexan parasites of invertebrates. The gregarine classification is largely incomplete because it relies primarily on light microscopy, while electron microscopy and molecular data in the group are fragmentary and often do not overlap. A key characteristic in gregarine taxonomy is the structure and function of their attachment organelles (AOs). AOs have been commonly classified as “mucrons” or “epimerites” based on their association with other cellular traits such as septation. An alternative proposal focused on the AOs structure, functional role, and developmental fate has recently restricted the terms “mucron” to archigregarines and “epimerite” to eugregarines. Methods Light microscopy and scanning and transmission electron microscopy, molecular phylogenetic analyses of ribosomal RNA genes. Results We obtained the first data on fine morphology of aseptate eugregarines Polyrhabdina pygospionis and Polyrhabdina cf. spionis, the type species. We demonstrate that their AOs differ from the mucron in archigregarines and represent an epimerite structurally resembling that in other eugregarines examined using electron microscopy. We then used the concatenated ribosomal operon DNA sequences (SSU, 5.8S, and LSU rDNA) of P. pygospionis to explore the phylogeny of eugregarines with a resolution superior to SSU rDNA alone. The obtained phylogenies show that the Polyrhabdina clade represents an independent, deep-branching family in the Ancoroidea clade within eugregarines. Combined, these results lend strong support to the hypothesis that the epimerite is a synapomorphic innovation of eugregarines. Based on these findings, we resurrect the family Polyrhabdinidae Kamm, 1922 and erect and diagnose the family Trollidiidae fam. n. within the superfamily Ancoroidea Simdyanov et al., 2017. Additionally, we re-describe the characteristics of P. pygospionis, emend the diagnoses of the genus Polyrhabdina, the family Polyrhabdinidae, and the superfamily Ancoroidea.
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Affiliation(s)
- Gita G Paskerova
- Department of Invertebrate Zoology, Faculty of Biology, St Petersburg State University, St Petersburg, Russia
| | - Tatiana S Miroliubova
- Laboratory for Fauna and Systematics of Parasites, Center for Parasitology, Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, Moscow, Russian Federation
| | - Andrea Valigurová
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Jan Janouškovec
- Centre Algatech, Institute of Microbiology of the Czech Academy of Sciences, Třeboň, Czech Republic
| | - Magdaléna Kováčiková
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Andrei Diakin
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Yuliya Ya Sokolova
- Institute of Cytology, Russian Academy of Sciences, St Petersburg, Russian Federation
| | - Kirill V Mikhailov
- Belozersky Institute for Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russian Federation.,Kharkevich Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow, Russian Federation
| | - Vladimir V Aleoshin
- Belozersky Institute for Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russian Federation.,Kharkevich Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow, Russian Federation
| | - Timur G Simdyanov
- Department of Invertebrate Zoology, Faculty of Biology, Lomonosov Moscow State University, Moscow, Russian Federation
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Frolova EV, Paskerova GG, Smirnov AV, Nassonova ES. Molecular phylogeny and new light microscopic data of Metchnikovella spiralis (Microsporidia: Metchnikovellidae), a hyperparasite of eugregarine Polyrhabdina sp. from the polychaete Pygospio elegans. Parasitology 2021; 148:779-786. [PMID: 33843504 PMCID: PMC11010189 DOI: 10.1017/s0031182021000603] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Revised: 03/19/2021] [Accepted: 03/29/2021] [Indexed: 11/07/2022]
Abstract
Metchnikovellids are a deep-branching group of microsporidia, parasites of gregarines inhabiting the alimentary tract of polychaetes and some other invertebrates. The diversity and phylogeny of these hyperparasites remain poorly studied. Modern descriptions and molecular data are still lacking for many species. The results of a light microscopy study and molecular data for Metchnikovella spiralis Sokolova et al., 2014, a hyperparasite of the eugregarine Polyrhabdina sp., isolated from the polychaete Pygospio elegans, were obtained. The original description of M. spiralis was based primarily on the analysis of stained preparations and transmission electron microscopy images. Here, the species description was complemented with the results of in vivo observations and phylogenetic analysis based on the SSU rRNA gene. It was shown that in this species, free sporogony precedes sac-bound sporogony, as it occurs in the life cycle of most other metchnikovellids. Spore sacs are entwined with spirally wound cords, and possess only one polar plug. Phylogenetic analyses did not group M. spiralis with M. incurvata, another metchnikovellid from the same gregarine species, but placed it as a sister branch to Amphiacantha. The paraphyletic nature of the genus Metchnikovella was discussed. The taxonomic summary for M. spiralis was emended.
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Affiliation(s)
- Ekaterina V. Frolova
- Laboratory of Cytology of Unicellular Organisms, Institute of Cytology RAS, Tikhoretsky ave. 4, Saint Petersburg194064, Russian Federation
- Department of Invertebrate Zoology, Faculty of Biology, Saint Petersburg State University, Universitetskaya emb. 7/9, Saint Petersburg199034, Russian Federation
| | - Gita G. Paskerova
- Department of Invertebrate Zoology, Faculty of Biology, Saint Petersburg State University, Universitetskaya emb. 7/9, Saint Petersburg199034, Russian Federation
| | - Alexey V. Smirnov
- Department of Invertebrate Zoology, Faculty of Biology, Saint Petersburg State University, Universitetskaya emb. 7/9, Saint Petersburg199034, Russian Federation
| | - Elena S. Nassonova
- Laboratory of Cytology of Unicellular Organisms, Institute of Cytology RAS, Tikhoretsky ave. 4, Saint Petersburg194064, Russian Federation
- Department of Invertebrate Zoology, Faculty of Biology, Saint Petersburg State University, Universitetskaya emb. 7/9, Saint Petersburg199034, Russian Federation
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7
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Sokolova YY, Overstreet RM, Heard RW, Isakova NP. Two new species of Unikaryon (Microsporidia) hyperparasitic in microphallid metacercariae (Digenea) from Florida intertidal crabs. J Invertebr Pathol 2021; 182:107582. [PMID: 33775675 DOI: 10.1016/j.jip.2021.107582] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 03/15/2021] [Accepted: 03/20/2021] [Indexed: 10/21/2022]
Abstract
The genus Unikaryon (Microsporidia) holds exclusively hyperparasites of Platyhelminthes. Four species of Unikaryon are presently known from trematodes infecting mollusks and fish, and one from a cestode infecting a fish. Here we report two species of Unikaryon from microphallid trematode metacercariae parasitizing the brachyuran crabs, Panopeus herbstii and Pachygrapsus transversus, collected from intertidal habitats in Florida. The first microsporidium, which we assign here to a new species, Unikaryon panopei sp. n., was isolated from Microphallus sp. encysted in Panopeus herbstii from Tampa Bay. The specific designation for the second Unikaryon sp. (Unikaryon sp. 2), which occurred in metacercaria of Diacetabulum sp. found in P. transversus from the Florida Keys, is pending due to the lack of SSrDNA sequence data. Light and electron microscopy demonstrates that both species display characteristics of the genus Unikaryon including the arrangement of spores in sets of two, large posterior vacuole, and eccentric position of the polar filament. Spores of Unikaryon panopei sp. n., unlike those of Unikaryon sp. 2, assemble in large membrane-bound masses containing hundreds of organisms, and display a larger number of polar filament coils - 7-8, compared to 4-5 in Unikaryon sp. 2 The SSUrDNA-inferred phylogenetic analysis places Unikaryon panopei in one clade with Unikaryon legeri, the only other molecularly characterized member of the genus, with 94% of SSUrDNA similarity. These findings increase the number of species parasitizing trematodes and broaden the host range of Unikaryon spp.
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Affiliation(s)
- Yuliya Y Sokolova
- Insitute of Cytology RAS, St. Petersburg, Russia; School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, USA.
| | - Robin M Overstreet
- University of Southern Mississippi, Gulf Coast Res. Laboratory, Ocean Springs, MS, USA
| | - Richard W Heard
- University of Southern Mississippi, Gulf Coast Res. Laboratory, Ocean Springs, MS, USA
| | - Nadezhda P Isakova
- The Herzen State Pedagogical University, Dept. Zoology, St. Petersburg, Russia
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Nassonova ES, Bondarenko NI, Paskerova GG, Kováčiková M, Frolova EV, Smirnov AV. Evolutionary relationships of Metchnikovella dogieli Paskerova et al., 2016 (Microsporidia: Metchnikovellidae) revealed by multigene phylogenetic analysis. Parasitol Res 2021; 120:525-534. [PMID: 33415389 DOI: 10.1007/s00436-020-06976-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 11/12/2020] [Indexed: 12/12/2022]
Abstract
The species Metchnikovella dogieli (Paskerova et al. Protistology 10:148-157, 2016) belongs to one of the early diverging microsporidian groups, the metchnikovellids (Microsporidia: Metchnikovellidae). In relation to typical ('core') microsporidia, this group is considered primitive. The spores of metchnikovellids have no classical polar sac-anchoring disk complex, no coiled polar tube, no posterior vacuole, and no polaroplast. Instead, they possess a short thick manubrium that expands into a manubrial cistern. These organisms are hyperparasites; they infect gregarines that parasitise marine invertebrates. M. dogieli is a parasite of the archigregarine Selenidium pygospionis (Paskerova et al. Protist 169:826-852, 2018), which parasitises the polychaete Pygospio elegans. This species was discovered in samples collected in the silt littoral zone at the coast of the White Sea, North-West Russia, and was described based on light microscopy. No molecular data are available for this species, and the publicly accessible genomic data for metchnikovellids are limited to two species: M. incurvata Caullery & Mesnil, 1914 and Amphiamblys sp. WSBS2006. In the present study, we applied single-cell genomics methods with whole-genome amplification to perform next-generation sequencing of M. dogieli genomic DNA. We performed a phylogenetic analysis based on the SSU rRNA gene and reconstructed a multigene phylogeny using a concatenated alignment that included 46 conserved single-copy protein domains. The analyses recovered a fully supported clade of metchnikovellids as a basal group to the core microsporidia. Two members of the genus Metchnikovella did not form a clade in our tree. This may indicate that this genus is paraphyletic and requires revision.
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Affiliation(s)
- Elena S Nassonova
- Laboratory of Cytology of Unicellular Organisms, Institute of Cytology RAS, Tikhoretsky ave. 4, St. Petersburg, Russia, 194064. .,Department of Invertebrate Zoology, Faculty of Biology, St. Petersburg State University, Universitetskaya nab. 7/9, St. Petersburg, Russia, 199034.
| | - Natalya I Bondarenko
- Laboratory of Cytology of Unicellular Organisms, Institute of Cytology RAS, Tikhoretsky ave. 4, St. Petersburg, Russia, 194064.,Department of Invertebrate Zoology, Faculty of Biology, St. Petersburg State University, Universitetskaya nab. 7/9, St. Petersburg, Russia, 199034
| | - Gita G Paskerova
- Department of Invertebrate Zoology, Faculty of Biology, St. Petersburg State University, Universitetskaya nab. 7/9, St. Petersburg, Russia, 199034
| | - Magdaléna Kováčiková
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Kotlářská 2, 611 37, Brno, Czech Republic
| | - Ekaterina V Frolova
- Laboratory of Cytology of Unicellular Organisms, Institute of Cytology RAS, Tikhoretsky ave. 4, St. Petersburg, Russia, 194064.,Department of Invertebrate Zoology, Faculty of Biology, St. Petersburg State University, Universitetskaya nab. 7/9, St. Petersburg, Russia, 199034
| | - Alexey V Smirnov
- Department of Invertebrate Zoology, Faculty of Biology, St. Petersburg State University, Universitetskaya nab. 7/9, St. Petersburg, Russia, 199034
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Yakovleva Y, Nassonova E, Lebedeva N, Lanzoni O, Petroni G, Potekhin A, Sabaneyeva E. The first case of microsporidiosis in Paramecium. Parasitology 2020; 147:957-971. [PMID: 32338239 PMCID: PMC10317679 DOI: 10.1017/s0031182020000633] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 02/29/2020] [Accepted: 04/08/2020] [Indexed: 11/06/2022]
Abstract
A new microsporidian species, Globosporidium paramecii gen. nov., sp. nov., from Paramecium primaurelia is described on the basis of morphology, fine structure, and SSU rRNA gene sequence. This is the first case of microsporidiosis in Paramecium reported so far. All observed stages of the life cycle are monokaryotic. The parasites develop in the cytoplasm, at least some part of the population in endoplasmic reticulum and its derivates. Meronts divide by binary fission. Sporogonial plasmodium divides by rosette-like budding. Early sporoblasts demonstrate a well-developed exospore forming blister-like structures. Spores with distinctive spherical shape are dimorphic in size (3.7 ± 0.2 and 1.9 ± 0.2 μm). Both types of spores are characterized by a thin endospore, a short isofilar polar tube making one incomplete coil, a bipartite polaroplast, and a large posterior vacuole. Experimental infection was successful for 5 of 10 tested strains of the Paramecium aurelia species complex. All susceptible strains belong to closely related P. primaurelia and P. pentaurelia species. Phylogenetic analysis placed the new species in the Clade 4 of Microsporidia and revealed its close relationship to Euplotespora binucleata (a microsporidium from the ciliate Euplotes woodruffi), to Helmichia lacustris and Mrazekia macrocyclopis, microsporidia from aquatic invertebrates.
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Affiliation(s)
- Yulia Yakovleva
- Department of Cytology and Histology, Saint Petersburg State University, Universitetskaya emb. 7/9, 199034Saint Petersburg, Russian Federation
| | - Elena Nassonova
- Laboratory of Cytology of Unicellular Organisms, Institute of Cytology RAS, Tikhoretsky ave. 4, 194064Saint Petersburg, Russian Federation
- Department of Invertebrate Zoology, Saint Petersburg State University, Universitetskaya emb. 7/9, 199034Saint Petersburg, Russian Federation
| | - Natalia Lebedeva
- Core Facility Center for Cultivation of Microorganisms, Saint Petersburg State University, Peterhof, Botanicheskaya st. 17, 198504Saint Petersburg, Russian Federation
| | - Olivia Lanzoni
- Department of Biology, University of Pisa, via A Volta 4, 56126Pisa, Italy
| | - Giulio Petroni
- Department of Biology, University of Pisa, via A Volta 4, 56126Pisa, Italy
| | - Alexey Potekhin
- Department of Microbiology, Saint Petersburg State University, 16th line, Vasilyevsky Island, 29, 199178Saint Petersburg, Russian Federation
| | - Elena Sabaneyeva
- Department of Cytology and Histology, Saint Petersburg State University, Universitetskaya emb. 7/9, 199034Saint Petersburg, Russian Federation
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10
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Filling gaps in the microsporidian tree: rDNA phylogeny of Chytridiopsis typographi (Microsporidia: Chytridiopsida). Parasitol Res 2018; 118:169-180. [DOI: 10.1007/s00436-018-6130-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 10/23/2018] [Indexed: 12/18/2022]
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11
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Galindo LJ, Torruella G, Moreira D, Timpano H, Paskerova G, Smirnov A, Nassonova E, López-García P. Evolutionary Genomics of Metchnikovella incurvata (Metchnikovellidae): An Early Branching Microsporidium. Genome Biol Evol 2018; 10:2736-2748. [PMID: 30239727 PMCID: PMC6190962 DOI: 10.1093/gbe/evy205] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/12/2018] [Indexed: 01/30/2023] Open
Abstract
Metchnikovellids are highly specialized hyperparasites, which infect and reproduce inside gregarines (Apicomplexa) inhabiting marine invertebrates. Their phylogenetic affiliation was under constant discussion until recently, when analysis of the first near-complete metchnikovellid genome, that of Amphiamblys sp., placed it in a basal position with respect to most Microsporidia. Microsporidia are a highly diversified lineage of extremely reduced parasites related to Rozellida (Rozellosporidia = Rozellomycota = Cryptomycota) within the Holomycota clade of Opisthokonta. By sequencing DNA from a single-isolated infected gregarine cell we obtained an almost complete genome of a second metchnikovellid species, and the first one of a taxonomically described and well-documented species, Metchnikovella incurvata. Our phylogenomic analyses show that, despite being considerably divergent from each other, M. incurvata forms a monophyletic group with Amphiamplys sp., and confirm that metchnikovellids are one of the deep branches of Microsporidia. Comparative genomic analysis demonstrates that, like most Microsporidia, metchnikovellids lack mitochondrial genes involved in energy transduction and are thus incapable of synthesizing their own ATP via mitochondrial oxidative phosphorylation. They also lack the horizontally acquired ATP transporters widespread in most Microsporidia. We hypothesize that a family of mitochondrial carrier proteins evolved to transport ATP from the host into the metchnikovellid cell. We observe the progressive reduction of genes involved in DNA repair pathways along the evolutionary path of Microsporidia, which might explain, at least partly, the extremely high evolutionary rate of the most derived species. Our data also suggest that genome reduction and acquisition of novel genes co-occurred during the adaptation of Microsporidia to their hosts.
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Affiliation(s)
- Luis Javier Galindo
- Ecologie Systématique Evolution, CNRS, Université Paris-Sud, AgroParisTech, Université Paris-Saclay, Orsay, France
| | - Guifré Torruella
- Ecologie Systématique Evolution, CNRS, Université Paris-Sud, AgroParisTech, Université Paris-Saclay, Orsay, France
| | - David Moreira
- Ecologie Systématique Evolution, CNRS, Université Paris-Sud, AgroParisTech, Université Paris-Saclay, Orsay, France
| | - Hélène Timpano
- Ecologie Systématique Evolution, CNRS, Université Paris-Sud, AgroParisTech, Université Paris-Saclay, Orsay, France
| | - Gita Paskerova
- Department of Invertebrate Zoology, Faculty of Biology, St Petersburg State University, Russia
| | - Alexey Smirnov
- Department of Invertebrate Zoology, Faculty of Biology, St Petersburg State University, Russia
| | - Elena Nassonova
- Department of Invertebrate Zoology, Faculty of Biology, St Petersburg State University, Russia.,Laboratory of Cytology of Unicellular Organisms, Institute of Cytology Russian Academy of Sciences, St. Petersburg, Russia
| | - Purificación López-García
- Ecologie Systématique Evolution, CNRS, Université Paris-Sud, AgroParisTech, Université Paris-Saclay, Orsay, France
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12
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Wijayawardene NN, Pawłowska J, Letcher PM, Kirk PM, Humber RA, Schüßler A, Wrzosek M, Muszewska A, Okrasińska A, Istel Ł, Gęsiorska A, Mungai P, Lateef AA, Rajeshkumar KC, Singh RV, Radek R, Walther G, Wagner L, Walker C, Wijesundara DSA, Papizadeh M, Dolatabadi S, Shenoy BD, Tokarev YS, Lumyong S, Hyde KD. Notes for genera: basal clades of Fungi (including Aphelidiomycota, Basidiobolomycota, Blastocladiomycota, Calcarisporiellomycota, Caulochytriomycota, Chytridiomycota, Entomophthoromycota, Glomeromycota, Kickxellomycota, Monoblepharomycota, Mortierellomycota, Mucoromycota, Neocallimastigomycota, Olpidiomycota, Rozellomycota and Zoopagomycota). FUNGAL DIVERS 2018. [DOI: 10.1007/s13225-018-0409-5] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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13
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Fine structure and Molecular Phylogenetic Position of Two Marine Gregarines, Selenidium pygospionis sp. n. and S. pherusae sp. n., with Notes on the Phylogeny of Archigregarinida (Apicomplexa). Protist 2018; 169:826-852. [PMID: 30453272 DOI: 10.1016/j.protis.2018.06.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 05/26/2018] [Accepted: 06/19/2018] [Indexed: 11/23/2022]
Abstract
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.
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Mikhailov KV, Simdyanov TG, Aleoshin VV. Genomic Survey of a Hyperparasitic Microsporidian Amphiamblys sp. (Metchnikovellidae). Genome Biol Evol 2017; 9:454-467. [PMID: 27694476 PMCID: PMC5381614 DOI: 10.1093/gbe/evw235] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/27/2016] [Indexed: 12/18/2022] Open
Abstract
Metchnikovellidae are a group of unusual microsporidians that lack some of the defining ultrastructural features characteristic of derived Microsporidia and are thought to be one of their earliest-branching lineages. The basal position of metchnikovellids was never confirmed by molecular phylogeny in published research, and thus far no genomic data for this group were available. In this work, we obtain a partial genome of metchnikovellid Amphiamblys sp. using multiple displacement amplification, next-generation sequencing, and metagenomic binning approaches. The partial genome, which we estimate to be close to 90% complete, displays genome compaction on par with gene-dense microsporidian genomes, but contains an unusual repertoire of unique repeat elements. Phylogenetic analyses of multigene datasets place Amphiamblys sp. as the first branch of the microsporidian lineage following the divergence of a mitochondriate microsporidian Mitosporidium. We find evidence for a mitochondrial remnant presumably functionally equivalent to a mitosome in Amphiamblys sp. and the common enzymatic complement for microsporidian anaerobic metabolism. Comparative genomic analyses identify the conservation of components for clathrin vesicle formation as one of the key features distinguishing the metchnikovellid from its highly derived relatives. The presented data confirm the notion of Metchnikovellidae as a less derived microsporidian group, and provide an additional stepping stone for reconstruction of an evolutionary transition from the early diverging parasitic fungi to derived Microsporidia.
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Affiliation(s)
- Kirill V. Mikhailov
- A.N. Belozersky Institute for Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russian Federation
- A.A. Kharkevich Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow, Russian Federation
| | - Timur G. Simdyanov
- Faculty of Biology, Lomonosov Moscow State University, Moscow, Russian Federation
| | - Vladimir V. Aleoshin
- A.N. Belozersky Institute for Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russian Federation
- A.A. Kharkevich Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow, Russian Federation
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15
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Hyperspora aquatica n.gn., n.sp. (Microsporidia), hyperparasitic in Marteilia cochillia (Paramyxida), is closely related to crustacean-infecting microspordian taxa. Parasitology 2016; 144:186-199. [PMID: 27748227 DOI: 10.1017/s0031182016001633] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The Paramyxida, closely related to haplosporidians, paradinids, and mikrocytids, is an obscure order of parasitic protists within the class Ascetosporea. All characterized ascetosporeans are parasites of invertebrate hosts, including molluscs, crustaceans and polychaetes. Representatives of the genus Marteilia are the best studied paramyxids, largely due to their impact on cultured oyster stocks, and their listing in international legislative frameworks. Although several examples of microsporidian hyperparasitism of paramyxids have been reported, phylogenetic data for these taxa are lacking. Recently, a microsporidian parasite was described infecting the paramyxid Marteilia cochillia, a serious pathogen of European cockles. In the current study, we investigated the phylogeny of the microsporidian hyperparasite infecting M. cochillia in cockles and, a further hyperparasite, Unikaryon legeri infecting the digenean Meiogymnophallus minutus, also in cockles. We show that rather than representing basally branching taxa in the increasingly replete Cryptomycota/Rozellomycota outgroup (containing taxa such as Mitosporidium and Paramicrosoridium), these hyperparasites instead group with other known microsporidian parasites infecting aquatic crustaceans. In doing so, we erect a new genus and species (Hyperspora aquatica n. gn., n.sp.) to contain the hyperparasite of M. cochillia and clarify the phylogenetic position of U. legeri. We propose that in both cases, hyperparasitism may provide a strategy for the vectoring of microsporidians between hosts of different trophic status (e.g. molluscs to crustaceans) within aquatic systems. In particular, we propose that the paramyxid hyperparasite H. aquatica may eventually be detected as a parasite of marine crustaceans. The potential route of transmission of the microsporidian between the paramyxid (in its host cockle) to crustaceans, and, the 'hitch-hiking' strategy employed by H. aquatica is discussed.
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Haag KL, James TY, Pombert JF, Larsson R, Schaer TMM, Refardt D, Ebert D. Evolution of a morphological novelty occurred before genome compaction in a lineage of extreme parasites. Proc Natl Acad Sci U S A 2014; 111:15480-5. [PMID: 25313038 PMCID: PMC4217409 DOI: 10.1073/pnas.1410442111] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Intracellular parasitism results in extreme adaptations, whose evolutionary history is difficult to understand, because the parasites and their known free-living relatives are so divergent from one another. Microsporidia are intracellular parasites of humans and other animals, which evolved highly specialized morphological structures, but also extreme physiologic and genomic simplification. They are suggested to be an early-diverging branch on the fungal tree, but comparisons to other species are difficult because their rates of molecular evolution are exceptionally high. Mitochondria in microsporidia have degenerated into organelles called mitosomes, which have lost a genome and the ability to produce ATP. Here we describe a gut parasite of the crustacean Daphnia that despite having remarkable morphological similarity to the microsporidia, has retained genomic features of its fungal ancestors. This parasite, which we name Mitosporidium daphniae gen. et sp. nov., possesses a mitochondrial genome including genes for oxidative phosphorylation, yet a spore stage with a highly specialized infection apparatus--the polar tube--uniquely known only from microsporidia. Phylogenomics places M. daphniae at the root of the microsporidia. A comparative genomic analysis suggests that the reduction in energy metabolism, a prominent feature of microsporidian evolution, was preceded by a reduction in the machinery controlling cell cycle, DNA recombination, repair, and gene expression. These data show that the morphological features unique to M. daphniae and other microsporidia were already present before the lineage evolved the extreme host metabolic dependence and loss of mitochondrial respiration for which microsporidia are well known.
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Affiliation(s)
- Karen L Haag
- Zoological Institute, Basel University, 4051 Basel, Switzerland; Department of Genetics, Federal University of Rio Grande do Sul, Porto Alegre, 91501-970 RS, Brazil;
| | - Timothy Y James
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109
| | - Jean-François Pombert
- Department of Biological and Chemical Sciences, Illinois Institute of Technology, Chicago, IL 60616
| | - Ronny Larsson
- Department of Biology, University of Lund, SE-223 62 Lund, Sweden; and
| | | | - Dominik Refardt
- Zoological Institute, Basel University, 4051 Basel, Switzerland; Institute of Natural Resource Sciences, Zurich University of Applied Sciences, 8820 Wädenswil, Switzerland
| | - Dieter Ebert
- Zoological Institute, Basel University, 4051 Basel, Switzerland
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Sokolova Y, Pelin A, Hawke J, Corradi N. Morphology and phylogeny of Agmasoma penaei (Microsporidia) from the type host, Litopenaeus setiferus, and the type locality, Louisiana, USA. Int J Parasitol 2014; 45:1-16. [PMID: 25449947 DOI: 10.1016/j.ijpara.2014.07.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 07/15/2014] [Accepted: 07/16/2014] [Indexed: 10/24/2022]
Abstract
Since June 2012, samples of wild caught white shrimp, Litopenaeus setiferus, from the Gulf of Mexico, Plaquemines and Jefferson Parishes (Louisiana, USA) with clinical signs of microsporidiosis have been delivered to the Louisiana Aquatic Diagnostic Laboratory for identification. Infection was limited predominantly to female gonads and was caused by a microsporidium producing roundish pansporoblasts with eight spores (3.6×2.1 μm) and an anisofilar (2-3+4-6) polar filament. These features allowed identification of the microsporidium as Agmasoma penaei Sprague, 1950. Agmasoma penaei is known as a microsporidium with world-wide distribution, causing devastating epizootic disease among wild and cultured shrimps. This paper provides molecular and morphological characterisation of A. penaei from the type host and type locality. Comparison of the novel ssrDNA sequence of A. penaei from Louisiana, USA with that of A. penaei from Thailand revealed 95% similarity, which suggests these geographical isolates are two different species. The A. penaei sequences did not show significant homology to any other examined taxon. Phylogenetic reconstructions using the ssrDNA and alpha- and beta-tubulin sequences supported its affiliation with the Clade IV Terresporidia sensu Vossbrink 2005, and its association with parasites of fresh and salt water crustaceans of the genera Artemia, Daphnia and Cyclops.
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Affiliation(s)
- Yuliya Sokolova
- Department of Comparative Biomedical Studies, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, USA; Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia.
| | - Adrian Pelin
- Canadian Institute for Advanced Research, Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - John Hawke
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, USA
| | - Nicolas Corradi
- Canadian Institute for Advanced Research, Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5, Canada
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Toguebaye BS, Quilichini Y, Diagne PM, Marchand B. Ultrastructure and development of Nosema podocotyloidis n. sp. (Microsporidia), a hyperparasite of Podocotyloides magnatestis (Trematoda), a parasite of Parapristipoma octolineatum (Teleostei). Parasite 2014; 21:44. [PMID: 25174849 PMCID: PMC4150386 DOI: 10.1051/parasite/2014044] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 08/08/2014] [Indexed: 11/14/2022] Open
Abstract
Nosema podocotyloidis n. sp. (Microsporidia, Nosematidae) is described from Podocotyloides magnatestis (Trematoda: Opecoelidae), a parasite of the fish Parapristipoma octolineatum (Teleostei) in the Atlantic Ocean. Electron microscopy reveals that all the stages of the cycle (merogony and sporogony) are diplokaryotic and in direct contact with the cytoplasm of host cells. There is no sporophorous vesicle (pansporoblast). The earliest stages observed are meronts, which have a simple plasmic membrane. Their cytoplasm is granular, rich in ribosomes and contains some sacculi of endoplasmic reticulum. They divide by binary fission into diplokaryotic sporonts. The sporonts have a thick electron-dense wall. Their diplokaryon is slightly less electron-dense than the cytoplasm. The cytoplasm of more advanced sporonts has numerous electron-lucent vesicles. Sporonts with two diplokarya divide by binary fission into diplokaryotic sporoblasts. The older sporoblasts are irregular or elongate and the polar filament is in formation. Their cytoplasm is denser, with ribosomes and lamellae of granular endoplasmic reticulum. The sporoblasts evolve into spores. The mature spores are broadly oval and measure 3.6 (3.1-4.0) × 2.58 (1.8-3.3) μm. Their wall is 100-300 nm thick. The polar tube is isofilar with 11-16 coils, 130-155 nm in diameter and arranged in many layers in the centre of the spore. The polaroplast is divided into two regions: an outer electron-dense cup with granular content and lacking lamellae and an internal region, less electron-dense, composed of irregularly arranged sacs. The posterior vacuole, with an amorphous electron-dense content, is present. The new species is compared with other species of Nosema from trematodes.
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Affiliation(s)
- Bhen Sikina Toguebaye
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Université Cheikh Anta Diop de Dakar, Laboratoire de Parasitologie, Faculté des Sciences et Techniques BP 5055 Dakar République du Sénégal
| | - Yann Quilichini
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CNRS – Université de Corse, UMR SPE 6134, Service d’Étude et de Recherche en Microscopie Électronique, Campus Grimaldi BP 52 20250 Corte Corse France
| | - Papa Mbagnick Diagne
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Université Cheikh Anta Diop de Dakar, Laboratoire de Biologie Évolutive, d’Écologie et de Gestion des Écosystèmes, Faculté des Sciences et Techniques BP 5055 Dakar République du Sénégal
| | - Bernard Marchand
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CNRS – Université de Corse, UMR SPE 6134, Service d’Étude et de Recherche en Microscopie Électronique, Campus Grimaldi BP 52 20250 Corte Corse France
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Description of Metchnikovella spiralis sp. n. (Microsporidia: Metchnikovellidae), with notes on the ultrastructure of metchnikovellids. Parasitology 2014; 141:1108-22. [DOI: 10.1017/s0031182014000420] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
SUMMARYThe present paper reports results of a transmission electron microscopy study of a new metchikovellid microsporidium. It was isolated from gregarines Polyrhabdina sp. inhabiting guts of polychaetes Pygospio elegans sampled at the White Sea silt littoral zone. Free sporogony (FS) occurred in the life cycle of the microsporidium alongside sac-bound sporogony (BS). Free spores resided in a parasitophorous vacuole and were of typical metchnikovellidean structure, uninucleate and oblong. They measured on sections 2·0–3·2×1·3–1·9 μm. The life cycle included pre-sporogonial stages represented by dikaryotic cells and 4-nucleate cells with coupled nuclei. A multinucleate sporogonial plasmodium of FS split in numerous (>10) sporoblasts. In BS segregation of sporoblasts occurred within thick-walled cysts by internal budding. Spore sacs of this microsporidium, measuring on average 11·6×4·7 μm, were limited by a thick electron-dense wall, externally ornamented with spirally wound cords of dense material. These oval spore sacs contained eight barrel-shaped spores, comparable in size and ultrastructure to FS spores. Ultrastructure of both types of spores and intracellular development of the new microsporidium and Metchnikovella spp. were similar, suggesting they belong to the same genus. In this paper we describe a new species Metchnikovella spiralis and discuss morphology of metchnikovellids in the context of putative evolutionary history of Microsporidia.
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Corsaro D, Walochnik J, Venditti D, Steinmann J, Müller KD, Michel R. Microsporidia-like parasites of amoebae belong to the early fungal lineage Rozellomycota. Parasitol Res 2014; 113:1909-18. [DOI: 10.1007/s00436-014-3838-4] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Accepted: 02/24/2014] [Indexed: 12/28/2022]
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21
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Microsporidia: diverse, dynamic, and emergent pathogens in aquatic systems. Trends Parasitol 2013; 29:567-78. [DOI: 10.1016/j.pt.2013.08.005] [Citation(s) in RCA: 150] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Revised: 08/29/2013] [Accepted: 08/30/2013] [Indexed: 12/22/2022]
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