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22. A novel endosymbiont-containing trypanosomatid Phytomonas borealis sp. n. from the predatory bug Picromerus bidens (Heteroptera: Pentatomidae)
- Creator:
- Ganyukova, Anna I, Frolov, Alexander O, Malysheva, Marina N, Spodareva, Viktoria V, Vyacheslav Yurchenko, and Kostygov, Alexei Yu
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- dravé ryby, predatory fishes, new trypanosomatid species, prokaryotic endosymbionts, non-specific infection, 2, and 59
- Language:
- English
- Description:
- Here we describe the new trypanosomatid, Phytomonas borealis sp. n., from the midgut of the spiked shieldbugs, Picromerus bidens (Linnaeus), collected in two locations, Novgorod and Pskov Oblasts of Russia. The phylogenetic analyses, based on the 18S rRNA gene, demonstrated that this flagellate is a sister species to the secondary monoxenous Phytomonas nordicus Frolov et Malysheva, 1993, which was concurrently documented in the same host species in Pskov Oblast. Unlike P. nordicus, which can complete its development (including exit to haemolymph and penetration into salivary glands) in Picromerus bidens, the new species did not form any extraintestinal stages in the host. It also did not produce endomastigotes, indispensable for transmission in other Phytomonas spp. These observations, along with the fact that P. bidens overwinters at the egg stage, led us to the conclusion that the examined infections with P. borealis were non-specific. Strikingly, the flagellates from the Novgorod population contained prokaryotic endosymbionts, whereas the parasites from the second locality were endosymbiont-free. This is a first case documenting presence of intracellular symbiotic bacteria in Phytomonas spp. We suggest that this novel endosymbiotic association arose very recently and did not become obligate yet. Further investigation of P. borealis and its intracellular bacteria may shed light on the origin and early evolution of endosymbiosis in trypanosomatids., Anna I. Ganyukova, Alexander O. Frolov, Marina N. Malysheva, Viktoria V. Spodareva, Vyacheslav Yurchenko and Alexei Yu. Kostygov., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
23. A novel myxozoan parasite of terrestrial mammals: description of Soricimyxum minuti sp. n. (Myxosporea) in pygmy shrew Sorex minutus from Hungary
- Creator:
- Székely, Csaba, Cech, Gábor, Atkinson, Stephen D, Kálmán Molnár, Egyed, László, and Gubányi, András
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- žlučové cesty, játra, biliary ducts, liver, Maďarsko, Hungary, Myxozoa, Soricimyxum spp., bile ducts, mammalian hosts, Sorex spp., 2, and 59
- Language:
- English
- Description:
- As part of a biodiversity study in northwestern Hungary, we conducted a parasitological survey of small mammals. In both common shrews (Sorex araneus Linnaeus) and pygmy shrews (Sorex minutus Linnaeus), we found myxospores of a species of Soricimyxum Prunescu, Prunescu, Pucek et Lom, 2007 (Myxosporea) and plasmodia in the bile ducts within the liver. Spores from both species of shrewswere morphologically and morphometrically indistinguishable, but differed in their SSU rRNA gene sequences by 3.3%. We identified spores and developmental stages from the common shrew as Soricimyxum fegati Prunescu, Prunescu, Pucek et Lom, 2007, based on morphometric data and DNA sequence similarity. Spores from the pygmy shrew were only 96.7% similar to S. fegati, hence we identified them as a novel myxosporean Soricimyxum minuti sp. n. This is only the second myxosporean parasite species described from mammals., Csaba Székely, Gábor Cech, Stephen D. Atkinson, Kálmán Molnár, László Egyed, András Gubányi., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
24. A novel stage-specific glycosomal nucleoside diphosphate kinase from Trypanosoma cruzi
- Creator:
- Cámara, María de los Milagros, Bouvier, León, Reigada, Chantal, Digirolamo, Fabio A, Sayé, Melisa, and Pereira, Claudio A
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- energetický metabolismus, energy metabolism, trypanosomatids, Chagas disease, glycosomes, trypomastigotes, 2, and 59
- Language:
- English
- Description:
- Nucleoside diphosphate kinases (NDPK) are key enzymes involved in the intracellular nucleotide maintenance in all living organisms, especially in trypanosomatids which are unable to synthesise purines de novo. Four putative NDPK isoforms were identified in the Trypanosoma cruzi Chagas, 1909 genome but only two of them were characterised so far. In this work, we studied a novel isoform from T. cruzi called TcNDPK3. This enzyme presents an atypical N-terminal extension similar to the DM10 domains. In T. cruzi, DM10 sequences targeted other NDPK isoform (TcNDPK2) to the cytoskeleton, but TcNDPK3 was localised in glycosomes despite lacking a typical peroxisomal targeting signal. In addition, TcNDPK3 was found only in the bloodstream trypomastigotes where glycolytic enzymes are very abundant. However, TcNDPK3 mRNA was also detected at lower levels in amastigotes suggesting regulation at protein and mRNA level. Finally, 33 TcNDPK3 gene orthologs were identified in the available kinetoplastid genomes. The characterisation of new glycosomal enzymes provides novel targets for drug development to use in therapies of trypanosomatid associated diseases., María de los Milagros Cámara, León Bouvier, Chantal Reigada, Fabio A. Digirolamo, Melisa Sayé, Claudio A. Pereira., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
25. A phylogenetic test of the parasite-host associations between Maculinea butterflies (Lepidoptera: Lycaenidae) and Myrmica ants (Hymenoptera: Formicidae)
- Creator:
- Jansen, Gunther, Vepsäläinen, Kari, and Savolainen, Riitta
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, coevolution, host switching, Large blues, local adaptation, Maculinea, Myrmica, Phengaris, 2, and 59
- Language:
- English
- Description:
- The parasitic caterpillars of Maculinea (Lepidoptera: Lycaenidae) need to be adopted and nursed by ants of the genus Myrmica (Hymenoptera: Formicidae). Each Maculinea species is locally associated with one or a few main and often several secondary host species. To determine whether the parasite-host associations bear marks of cophylogenetic constraints, we reconstructed phylogenies of Maculinea and Myrmica using DNA sequence data. We searched for evidence of cospeciation with a tree-independent (ParaFit) and tree-based (TreeFitter) method. This did not reveal any indication of phylogenetic host tracking in Maculinea. This agrees with earlier insights, which emphasise that as most of the potential host ant populations are never infested by Maculinea, the selective pressure of the butterflies on Myrmica is likely to be slight. Each Maculinea species also specialises on one or a few host plant species before adoption by ants. We suggest that Maculinea species have a substantial potential to accommodate evolutionarily to geographically changing ranges of potential Myrmica hosts, available at the oviposition sites of the butterflies. We use recently published evidence on geographically varying host ant species to discuss a suite of plausible scenarios of adaptive shifts to new Myrmica host species. and Gunther Jansen, Kari Vepsäläinen, Riitta Savolainen.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
26. A question of adaptability: climate and habitat change lower trait diversity in butterfly communities in south-western Germany
- Creator:
- Filz, Katharina J., Wiemers, Martin, Herrig, Anne, Weitzel, Matthias, and Schmitt, Thomas
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Lepidoptera, species decline, community composition change, habitat specialisation, functional groups, community temperature index, fallows, south-western Germany, 2, and 59
- Language:
- English
- Description:
- Invertebrate diversity has rapidly declined throughout Europe during the last century. Various reasons for this decrease have been proposed including human induced factors like climate change. Temperature changes alter distributions and occurrences of butterflies by determining habitat conditions at different scales. We evaluated changes in the composition of butterfly communities recorded at nine areas of fallow ground in south-western Germany in 1973, 1986, 2010 and 2012 using Pollard’s transect technique. To demonstrate the importance of climatic changes in affecting butterfly communities, we calculated the community temperature index (CTI) for each butterfly community in each year. Although they increased slightly, the CTI-values did not match the temperature trends recorded in the study region. However, the reduction in the standard deviations of the CTIs over time is reflected in the marked loss of cold- and warm-adapted species due to their inability to cope with temperature and land-use induced habitat changes. Results of our butterfly surveys indicate a marked decline in species richness and striking changes in the composition of the butterfly communities studied. This trend was most pronounced for habitat specialists, thus mirroring a depletion in trait diversity. Our results indicate that, in the course of large-scale anthropogenic changes, habitat degradation at smaller scales will continuously lead to the replacement of habitat specialists by ubiquitous species., Katharina J. Filz ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
27. A study on African animal trypanosomosis in four areas of Senegal
- Creator:
- Ravel, Sophie, Mediannikov, Oleg, Bossard, Géraldine, Desquesnes, Marc, Cuny, Gérard, and Davoust, Bernard
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- psi, osli, skot, epidemiologie, dogs, donkeys, cattle, epidemiology, Trypanosoma congolense, 2, and 59
- Language:
- English
- Description:
- In Senegal, several areas provide great potential for agriculture and animal production, but African animal trypanosomosis (AAT) is one of the major constraints to the development of more effective livestock production systems. A study was conducted to assess the current situation of AAT in this country. Surveys were carried out between June 2011 and September 2012 in four different areas: Dakar, Sine Saloum, Kedougou region and Basse Casamance in several animal species: dogs (152), donkeys (23), horses (63), sheep (43), goats (52) and cattle (104), distributed in the four sites. Molecular tools (PCR) indicated 3.4% positive animals including dogs, donkeys, a goat and cattle. The savannah type of Trypanosoma congolense Broden, 1904 (53% of positive cases) and the forest type of T. congolense (subgenus Nannomonas Hoare, 1964) were predominant. Trypanosoma vivax Ziemann, 1905 (subgenus Duttonella Chalmers, 1918) was only present in one animal and no trypanosome of the subgenus Trypanozoon Lühe, 1906 was found. Half of the positive cases were detected in Sine Saloum, where T. congolense savannah-type was predominant, and the other half in Basse Casamance, where T. congolense forest-type was predominant; no cases were found in Dakar or in the Kedougou region. A high risk of infection in dogs with T. congolense savannah-type was shown in Sine Saloum, requiring prevention and control of dogs in this area. The involvement of tsetse flies in the transmission of T. congolense in Sine Saloum and Basse Casamance is discussed., Sophie Ravel, Oleg Mediannikov, Géraldine Bossard, Marc Desquesnes, Gérard Cuny, Bernard Davoust., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
28. A synopsis of records of myxozoan parasites (Cnidaria: Myxozoa) from shrews, with additional data on Soricimyxum fegati from common shrew Sorex araneus in Hungary and pygmy shrew Sorex minutus in Slovakia
- Creator:
- Szíkely, Csaba, Atkinson, Stephen D, Kálmán Molnár, Egyed, László, Gubány, Andrási, and Cech, Gábor
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- játra, liver, Evropa střední, Europe, Central, Eurasian shrew, Eurasian pygmy shrew, myxozoan infection, bile ducts, mammal hosts, 2, and 59
- Language:
- English
- Description:
- Myxozoans (Cnidaria: Myxozoa) are almost exclusively endoparasites of aquatic vertebrates and invertebrates, with the notable exception being two species of Soricimyxum Prunescu, Prunescu, Pucek et Lom, 2007 described from terrestrial shrews (Soricidae) in central Europe. Myxospores of the two parasites are morphologically indistinguishable, but have SSU rDNA sequences that differ by about 4%. Herein, we report additional molecular and histology data from Soricimyxum fegati Prunescu, Prunescu, Pucek et Lom, 2007 from common shrew (Sorex araneus Linnaeus) from Hungary, and add a new geographic record for S. fegati in pygmy shrew (Sorex minutus Linnaeus) from Slovakia. A limited survey of shrews from the northern United States, Blarina brevicauda Say and Sorex sp. from New York, and Sorex spp. from Oregon, did not discover any infections, which is in stark contrast to the relatively high infection rates (up to 66%) in European shrew populations. We also provide a summary and discussion of literature records of species of Soricimyxum and a host survey. Given the lack of distinguishing morphological or morphometric characters between Soricimyxum spp., and the overlap in vertebrate hosts and geographic ranges, unambiguous identification of these closely related shrew parasites can presently only be achieved through sequence comparison of one or more variable SSU rDNA regions., Csaba Székely, Stephen D. Atkinson, Kálmán Molnár, László Egyed, András Gubányi, Gábor Cech., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
29. A synoptic review of Caryophyllaeus Gmelin, 1790 (Cestoda: Caryophyllidea), parasites of cyprinid fishes
- Creator:
- Barčák, Daniel, Oros, Mikuláš, Vladimíra Hanzelová, and Tomáš Scholz
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- tasemnice, sladkovodní ryby, kaprovití, biologická systematika, tapeworms, freshwater fishes, Cyprinidae, biological systematics, identification key, phylogenetic relationships, Palaearctic Region, 2, and 59
- Language:
- English
- Description:
- Tapeworms of the genus Caryophyllaeus Gmelin, 1790 (Caryophyllidea: Caryophyllaeidae), common parasites of cyprinid fishes, are reviewed and taxonomic status of 42 nominal taxa that have been placed in the genus during its long history is clarified. The following seven species occurring in the Palaearctic Region are recognised as valid: C. laticeps (Pallas, 1781), C. auriculatus (Kulakovskaya, 1961), C. balticus (Szidat, 1941) comb. n. (syn. Khawia baltica Szidat, 1941), C. brachycollis Janiszewska, 1953, C. fimbriceps Annenkova-Chlopina, 1919, C. syrdarjensis Skrjabin, 1913, and newly described Caryophyllaeus chondrostomi sp. n. (= C. laticeps morphotype 4 of Bazsalovicsová et al., 2014) from common nase, Chondrostoma nasus (Linnaeus), found in Austria and Slovakia. The new species differs by the paramuscular or cortical position of preovarian vitelline follicles, a large, robust body (up to 64 mm long), conspicuously long vas deferens, flabellate scolex with small wrinkles on the anterior margin, and anteriormost testes located in a relatively short distance from the anterior extremity. Caryophyllaeus kashmirenses Mehra, 1930 and Caryophyllaeus prussicus (Szidat, 1937) comb. n. are considered to be species inquirendae, C. truncatus von Siebold in Baird, 1853 and C. tuba von Siebold in Baird, 1853 are nomina nuda. Data on the morphology, host spectra, distribution and known life-cycles of valid species are provided. Phylogenetic interrelations of four species of the genus including its type species and newly described C. chondrostomi were assessed based on an analysis of sequences of lsrDNA and cox1. A key to identification of all valid species of Caryophyllaeus is also provided., Daniel Barčák, Mikuláš Oros, Vladimíra Hanzelová, Tomáš Scholz., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
30. A synoptic review of Promonobothrium Mackiewicz, 1968 (Cestoda: Caryophyllidea), parasites of suckers (Catostomidae) in North America, with description of two new species
- Creator:
- Oros, Mikuláš, Jan Brabec, Roman Kuchta, Choudhury, Anindo, and Tomáš Scholz
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- ryby, systematická zoologie, fylogeneze, fishes, animal classification, phylogeny, eucestoda, comparative morphology, taxonomy, new species, Nearctic Region, identification key, molecular phylogeny, 2, and 59
- Language:
- English
- Description:
- Monozoic cestodes of the recently amended genus Promonobothrium Mackiewicz, 1968 (Cestoda: Caryophyllidea), parasites of suckers (Cypriniformes: Catostomidae) in North America, are reviewed, with information on their host specificity, distribution and data on the scolex morphology of seven species studied for the first time using scanning electron microscopy (SEM). Evaluation of type and voucher specimens from museum collections and newly collected material of most species indicated the following valid nominal species: Promonobothrium minytremi Mackiewicz, 1968 (type species); P. ingens (Hunter, 1927); P. hunteri (Mackiewicz, 1963); P. ulmeri (Calentine et Mackiewicz, 1966); P. fossae (Williams, 1974) and P. mackiewiczi (Williams, 1974). Rogersus Williams, 1980 with its only species R. rogersi is transferred to Promonobothrium based on morphological and molecular data. Promonobothrium currani sp. n. and P. papiliovarium sp. n. are described from Ictiobus bubalus (Rafinesque) and Ictiobus niger (Rafinesque), and Erimyzon oblongus (Mitchill), respectively. The newly described species can be distinguished from the other congeners by the morphology of the scolex, the position of the anteriormost vitelline follicles and testes, the presence of postovarian vitelline follicles and the shape of the ovary. Molecular phylogenetic analyses of six species based on sequences of the small and large subunits of the nuclear ribosomal RNA genes (ssrDNA, lsrDNA) confirmed the monophyletic status of the genus and supported the validity of the species analysed. A key to identification of all species of Promonobothrium based on morphological characteristics is provided., Mikuláš Oros, Jan Brabec, Roman Kuchta, Anindo Choudhury, Tomáš Scholz., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public