This paper provides the first detailed description of a Tetracapsuloides species, Tetracapsuloides vermiformis n. sp., with vermiform stages in the bryozoan host, Fredericella sultana, and its experimental transmission from F. sultana to Cyprinus carpio. The suitability of morphological, biological and 18S rDNA sequence data for discrimination between malacosporean species is reviewed and recommendations are given for future descriptions. Presently, malacosporean species cannot be differentiated morphologically due to their cryptic nature and the lack of differential characters of spores and spore-forming stages in both hosts. We examined biological, morphological and molecular characters for the present description and for revising malacosporean taxonomy in general. As a result, Buddenbrockia plumatellae was split into two species, with its sac-like stages being ascribed to Buddenbrockia bryozoides n. comb. In addition to ribosomal DNA sequences multiple biological features rather than morphological characters are considered essential tools to improve malacosporean taxonomy in the future according to our analysis of the limited traits presently available.
- MeSH
- Bryozoa parazitologie MeSH
- interakce hostitele a parazita MeSH
- kapři MeSH
- Myxozoa genetika fyziologie MeSH
- nemoci ryb parazitologie MeSH
- organismy bez specifických patogenů MeSH
- parazitární nemoci u zvířat parazitologie přenos MeSH
- RNA ribozomální 18S genetika MeSH
- stadia vývoje MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Myxozoans are metazoan parasites whose traditional spore morphology-based taxonomy conflicts DNA based phylogenies. Freshwater species of the genus Hoferellus are parasites of the excretory system, with several members infecting food and ornamental fish species, as well as amphibians. This study aims to increase our understanding of their molecular diversity and development, aspects about which little is known, and to generate a molecular diagnostic tool to discriminate between different pathogenic and non-pathogenic Hoferellus spp. METHODS: SSU and ITS rDNA phylogeny, along with morphological descriptions using light and electron microscopy were used to identify and characterize Hoferellus species collected from the urinary system of fishes and frogs. A PCR-based diagnostic assay was designed to differentiate between cryptic Hoferellus spp in cyprinid fishes commonly cultured in Central Europe. RESULTS: Our phylogenetic results separate the species of Hoferellus into two phylogenetic sublineages which are indistinguishable on the basis of generic morphological traits: 1) The Hoferellus sensu stricto sublineage, which is composed of the type species Hoferellus cyprini, Hoferellus carassii and a cryptic species, Hoferellus sp. detected only molecularly in common carp. 2) The Hoferellus sensu lato sublineage into which the new species we described in this study, Hoferellus gnathonemi sp. n. from the kidney of the elephantnose fish and Hoferellus anurae from reed frogs, are placed together with Hoferellus gilsoni previously sequenced from European eel. Apart from phylogenetic analyses, we also provide novel ultrastructural data on the phagocytotic nature of some Hoferellus plasmodia and on the elusive intracellular stages ascribed to the presporogonic development of this genus. CONCLUSIONS: We provide molecular evidence of the polyphyly of the genus Hoferellus and provide novel morphological details of its members. Based on the presented data, we revise and propose emendation of the genus Hoferellus.
- MeSH
- Cyprinidae MeSH
- fylogeneze MeSH
- ledviny patologie MeSH
- molekulární sekvence - údaje MeSH
- Myxozoa klasifikace genetika izolace a purifikace ultrastruktura MeSH
- nemoci ryb parazitologie MeSH
- parazitární nemoci u zvířat parazitologie MeSH
- ribozomální DNA chemie genetika MeSH
- sekvence nukleotidů MeSH
- sekvenční analýza DNA veterinární MeSH
- žáby parazitologie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Our survey of marine fish from South Africa and Indonesia revealed the presence of two new myxosporean species of the genus Sphaeromyxa for which we provide morphological and sequence data. Sphaeromyxa clini n. sp. detected in three Clinus spp. and Muraenoclinus dorsalis from South Africa is morphologically similar to Sphaeromyxa noblei previously described from Heteroclinus whiteleggii from Australia and to several other sphaeromyxids with arcuate spores and rounded ends. This similarity is reflected by phylogenetic positioning of S. clini n. sp. which clusters within the 'incurvata' group of the Sphaeromyxa clade. It differs from morphologically similar species by spore and polar capsule dimensions, host specificity and geographic distribution. Sphaeromyxa limocapitis n. sp., described from Gephyroberyx darwinii from Java, is morphologically similar to sphaeromyxids with straight spores and to marine Myxidium species with spindle-shaped spores but differs from them by spore and polar capsule dimensions, host specificity and geographic distribution. S. limocapitis n. sp. represents a separate lineage of the Sphaeromyxa clade and appears to be a missing link in the evolution of sphaeromyxids.
- MeSH
- DNA chemie izolace a purifikace MeSH
- fylogeneze MeSH
- játra parazitologie MeSH
- mořská voda MeSH
- Myxozoa anatomie a histologie klasifikace genetika ultrastruktura MeSH
- nemoci ryb parazitologie MeSH
- parazitární nemoci u zvířat parazitologie MeSH
- Perciformes parazitologie MeSH
- sekvenční seřazení MeSH
- žlučník parazitologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Indonésie MeSH
- Jihoafrická republika MeSH
In order to clarify the phylogenetic relationships among the main marine myxosporean clades including newly established Ceratonova clade and scrutinizing their evolutionary origins, we performed large-scale phylogenetic analysis of all myxosporean species from the marine myxosporean lineage based on three gene analyses and statistical topology tests. Furthermore, we obtained new molecular data for Ceratonova shasta, C. gasterostea, eight Ceratomyxa species and one Myxodavisia species. We described five new species: Ceratomyxa ayami n. sp., C. leatherjacketi n. sp., C. synaphobranchi n. sp., C. verudaensis n. sp. and Myxodavisia bulani n. sp.; two of these formed a new, basal Ceratomyxa subclade. We identified that the Ceratomyxa clade is basal to all other marine myxosporean lineages, and Kudoa with Enteromyxum are the most recently branching clades. Topologies were least stable at the nodes connecting the marine urinary clade, the marine gall bladder clade and the Ceratonova clade. Bayesian inference analysis of SSU rDNA and the statistical tree topology tests suggested that Ceratonova is closely related to the Enteromyxum and Kudoa clades, which represent a large group of histozoic species. A close relationship between Ceratomyxa and Ceratonova was not supported, despite their similar myxospore morphologies. Overall, the site of sporulation in the vertebrate host is a more accurate predictor of phylogenetic relationships than the morphology of the myxospore.
- MeSH
- Bayesova věta MeSH
- biologická evoluce * MeSH
- fylogeneze * MeSH
- modely genetické MeSH
- Myxozoa klasifikace MeSH
- pravděpodobnostní funkce MeSH
- ribozomální DNA genetika MeSH
- sekvenční analýza DNA MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Myxosporea (Myxozoa), a group of parasitic Cnidaria, use mostly bony fishes (Teleostei) as intermediate hosts; however, they can also parasitize other vertebrates such as cartilaginous fish (Chondrichthyes). Molecular data of myxosporeans from sharks and rays (Elasmobranchii) revealed these parasites to be one of the most basal representatives in the myxosporean phylogenetic tree, suggesting their ancient evolutionary history. A new myxosporean species, Bipteria vetusta n. sp., was found in the gall bladder of rabbit fish, Chimaera monstrosa (Holocephali; Chondrichthyes), and ssrDNA-based phylogeny revealed its basal position within the marine myxosporean lineage. Molecular dating based on ssrDNA analysis suggested the origin of a stem lineage leading to the marine myxosporean lineage at the time of the origin of Chondrichthyes in the Silurian era. The two common lineages of Myxozoa, Myxosporea and Malacosporea, were estimated to have split from their common ancestor in the Cambrian era. Tracing the history of evolution of the "vertebrate host type" character in the context of molecular dating showed that cartilaginous fish represented an ancestral state for all myxosporeans. Teleosts were very likely subsequently parasitized by myxozoans four times, independently. Myxosporean radiation and diversification appear to correlate with intermediate host evolution. The first intermediate hosts of myxosporeans were cartilaginous fish. When bony fish evolved and radiated, myxosporeans switched and adapted to bony fish, and subsequently greatly diversified in this new host niche. We believe that the present study is the first attempt at molecular dating of myxozoan evolution based on an old myxosporean species – a living myxosporean fossil.
- MeSH
- biologická evoluce * MeSH
- fylogeneze MeSH
- interakce hostitele a parazita * MeSH
- molekulární sekvence - údaje MeSH
- Myxozoa klasifikace genetika růst a vývoj izolace a purifikace MeSH
- ribozomální DNA chemie genetika MeSH
- RNA ribozomální 18S genetika MeSH
- ryby parazitologie MeSH
- sekvenční analýza DNA MeSH
- shluková analýza MeSH
- žlučník parazitologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
UNLABELLED: Myxosporeans (Myxozoa), microscopic metazoan parasitic organisms, are poorly studied in the Arctic region. Our survey of benthic and pelagic fish (n = 234) collected in Isfjorden (Svalbard, Norway) together with detailed morphological and molecular examination revealed the presence of nine myxosporean species. We compared observed myxosporean diversity with diversity documented in regions close to the Arctic and revealed that water depth rather than geographic distribution is an important factor influencing myxosporean fauna. WE DESCRIBE THREE NEW MYXOSPOREAN SPECIES: Zschokkella siegfriedi n. sp. from kidney of Boreogadus saida, Parvicapsula petuniae n. sp. from the urinary bladder of Gymnocanthus tricuspis, and Sinuolinea arctica n. sp. from the urinary bladder of Myoxocephalus scorpius. We characterise Latyspora-like organism from kidney of Clupea harengus. We provide new data for Ceratomyxa porrecta, Myxidium gadi, Myxidium finnmarchicum, Schulmania aenigmatosa, and Parvicapsula irregularis comb. nov. The phylogenetic analyses including the newly obtained SSU and LSU rDNA data revealed that most of the species studied cluster in the marine urinary clade within the marine myxosporean lineage. Newly obtained sequences including the first molecular data for the member of the genus Schulmania, substantially enriched the Zschokkella subclade. C. porrecta and the two Myxidium species cluster within the Ceratomyxa and marine Myxidium clade, respectively. Newly described species, Z. siegfriedi n. sp., was revealed to be morphologically indistinguishable but genetically diverse from Zschokkella hildae known from numerous gadid fish. Therefore, we consider Z. siegfriedi to be a cryptic myxosporean species that might be misidentified with Z. hildae. A Latyspora-like organism was found to be taxonomically problematic due to its suture line and its distant phylogenetic position from the type species Latyspora scomberomori did not allow us to assign it to the genus Latyspora. Based on an increased taxon sampling and SSU + LSU rDNA-based phylogeny, evolutionary trends within the marine urinary clade are investigated.
- Publikační typ
- časopisecké články MeSH
Malacosporeans represent a small fraction of myxozoan biodiversity with only two genera and three species described. They cycle between bryozoans and freshwater fish. In this study, we (i) microscopically examine and screen different freshwater/marine fish species from various geographic locations and habitats for the presence of malacosporeans using PCR; (ii) study the morphology, prevalence, host species/habitat preference and distribution of malacosporeans; (iii) perform small subunit/large subunit rDNA and Elongation factor 2 based phylogenetic analyses of newly gathered data, together with all available malacosporean data in GenBank; and (iv) investigate the evolutionary trends of malacosporeans by mapping the morphology of bryozoan-related stages, host species, habitat and geographic data on the small subunit rDNA-based phylogenetic tree. We reveal a high prevalence and diversity of malacosporeans in several fish hosts in European freshwater habitats by adding five new species of Buddenbrockia and Tetracapsuloides from cyprinid and perciform fishes. Comprehensive phylogenetic analyses revealed that, apart from Buddenbrockia and Tetracapsuloides clades, a novel malacosporean lineage (likely a new genus) exists. The fish host species spectrum was extended for Buddenbrockia plumatellae and Buddenbrockia sp. 2. Co-infections of up to three malacosporean species were found in individual fish. The significant increase in malacosporean species richness revealed in the present study points to a hidden biodiversity in this parasite group. This is most probably due to the cryptic nature of malacosporean sporogonic and presporogonic stages and mostly asymptomatic infections in the fish hosts. The potential existence of malacosporean life cycles in the marine environment as well as the evolution of worm- and sac-like morphology is discussed. This study improves the understanding of the biodiversity, prevalence, distribution, habitat and host preference of malacosporeans and unveils their evolutionary trends.
- MeSH
- biodiverzita * MeSH
- biologická evoluce * MeSH
- elongační faktor 2 genetika MeSH
- molekulární sekvence - údaje MeSH
- Myxozoa klasifikace cytologie genetika MeSH
- protozoální DNA genetika MeSH
- ribozomální DNA chemie genetika MeSH
- RNA ribozomální 18S genetika MeSH
- RNA ribozomální genetika MeSH
- ryby parazitologie MeSH
- sekvenční analýza DNA MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Myxosporean infections that we diagnosed frequently in the urinary tract of Cynoscion nebulosus (Cuvier, 1830) and Cynoscion regalis (Bloch and Schneider, 1801) (Sciaenidae) collected in the estuarine systems of SC, USA, are described together with their etiological agent. Based on the morphology of spores and plasmodial stages, we identified the agent, in both fish host species, as Sinuolinea dimorpha (Davis, 1916), which is the type species of the genus. Based on sequences of SSU rDNA generated in this study from type host material, this species of SinuolineaDavis, 1917 has found its place in the current phylogenetic reconstruction of Myxozoa and enlarged the limited number of myxosporean genera represented in phylogenetic analyses by sequences of type species. Sequences of SSU rDNA of S. dimorpha from Cynoscion host species formed two clusters, irrespective of their host species, and also revealed differences within each cluster. These findings contribute to the acknowledgement of myxosporean cryptic species diversity, an important topic that emphasizes the general necessity of species delimitation and of continued effort to improve our knowledge of Myxosporea based on both morphology of spores and molecular data.
- Publikační typ
- časopisecké články MeSH
The role of CD4+ and CD8+ T lymphocytes in the development of a protective immune response against Cryptosporidium muris infection was studied by the reconstitution of severe combined immunodeficient (SCID) mice with well-defined populations of either naive or immune CD8+ or CD4+ T lymphocytes. Adoptive transfer of both naive and immune CD4+ T lymphocyte subpopulations protects SCID mice against cryptosporidiosis. Moreover, a significant biological impact of activated CD8+ T cells against gastric cryptosporidiosis was observed. The significant difference in the course and intensity of the infection in reconstituted SCID mice was found to be dependent on the protective function of both the CD4+ and CD8+ T-cell populations transferred. While SCID mice reconstituted with either immune or naive CD4+ or immune CD8+ T-cell subpopulations resolved the infection within 29, 37 and 51 days post-infection, respectively, those reconstituted with naive CD8+ T cells suffered from chronic infection similar to control SCID mice. Reconstitution with CD4+ T cells resulted in suppression of oocyst excretion and shortening of patent period in comparison with SCID mice reconstituted with CD8+ T cells. Thus, although CD4+ T cells are considered important in protective immunity, our results are the first to demonstrate the involvement of activated CD8+ T lymphocytes in the protection of mice against gastric cryptosporidiosis.
- MeSH
- CD4-pozitivní T-lymfocyty imunologie MeSH
- CD8-pozitivní T-lymfocyty imunologie MeSH
- Cryptosporidium imunologie MeSH
- kryptosporidióza imunologie MeSH
- myši SCID MeSH
- myši MeSH
- převzatá imunita MeSH
- žaludek imunologie parazitologie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Infection with Chloromyxum careni Mutschmann, 1999 was found in the Asian horned frog Megophrys nasuta from Malaysia and Indonesia. Kidney was the only organ infected. Coelozoic plasmodia up to 300 μm were localized in Bowman's space, embracing the glomerulus from all sides, or rarely in lumina of renal tubules. Plasmodia are polysporic, containing disporic pansporoblasts. Myxospores observed by light microscopy are colorless, variable in shape and size, measuring 6.0-8.5 × 5.0-6.5 μm, composed of two symmetrical valves joined by a meridian suture, containing four pyriform polar capsules 3.0-4.0 × 2.5-3.0 μm and a single sporoplasm. Each valve possesses 14-24 (median 21) fine longitudinal ridges clearly visible only in scanning electron microscopy. Rarely, atypical spores with a markedly pointed posterior pole and only 6-10 surface ridges are present in plasmodia together with typical spores. Both small subunit (SSU) and large subunit (LSU) rRNA gene sequences possess extremely long GU-rich inserts. In all SSU and LSU rDNA-based phylogenetic analyses, C. careni clustered as a distinct basal branch to the Myxobolus+Myxidium lieberkuehni clade, out of the marine Chloromyxum clade containing Chloromyxum leydigi, the type species of the genus. These morphological and phylogenetic data suggest erection of a new genus for the C. careni lineage, but we conservatively treat it as a Chloromyxum sensu lato until more information is available.
- MeSH
- fylogeneze MeSH
- molekulární sekvence - údaje MeSH
- Myxozoa anatomie a histologie klasifikace genetika izolace a purifikace MeSH
- parazitární nemoci u zvířat parazitologie MeSH
- Ranidae parazitologie MeSH
- ribozomální DNA genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Indonésie MeSH
- Malajsie MeSH
