European journal of protistology最新文献

{"title":"Enchelyothrix muria n. gen, n. sp., (Ciliophora, Litostomatea, Spathidiida), an extreme halotroph spathidiid from Maharloo Lake, Iran","authors":"Mahnaz Barmshuri ,&nbsp;Ondřej Pomahač ,&nbsp;William Bourland","doi":"10.1016/j.ejop.2023.126005","DOIUrl":"10.1016/j.ejop.2023.126005","url":null,"abstract":"<div><p><span><span>Although free-living ciliated protists<span> (Ciliophora) commonly inhabit aquatic and terrestrial biotopes of mild to moderate salinity (PSS-practical salinity scale S = 10–150), very few have adapted to life at more extreme salinities (&gt;150 to saturation). Such extreme </span></span>halophiles<span><span> or halotrophs are of interest from the standpoints of evolution, cell physiology, ecology, and even </span>astrobiology. In this work, we present the morphology, 18S rRNA gene sequence, and </span></span>phylogenetic analysis<span> of a novel spathidiid ciliate (Ciliophora, Litosatomatea) that thrives in saturated brines of Maharloo Lake, Iran. Based on its unique combination of morphologic features, its molecular characterization, and its unusual ecology, it is assigned to a newly erected monotypic genus incertae sedis in order Spathidiida. The new species differs from other spathidiids by: a cell with a very short acutely pointed tail, the absence of a circumoral kinety with, instead, inclined, interrupted circumoral kinetofragments at the anterior end of somatic kineties and brush rows abutting the oral bulge, the absence of a contractile vacuole, a heteromorphic dorsal brush comprising five or six rows, and an extreme (at or near saturation) hypersaline habitat. We briefly discuss the persistent uncertainties regarding the phylogenetic relationships within the order Spathidiida.</span></p></div>","PeriodicalId":12042,"journal":{"name":"European journal of protistology","volume":"90 ","pages":"Article 126005"},"PeriodicalIF":2.9,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10207356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular characterization of methionine aminopeptidase1 from Eimeria tenella","authors":"Ke Xiao ,&nbsp;Qiping Zhao ,&nbsp;Haixia Wang,&nbsp;Shunhai Zhu,&nbsp;Hui Dong,&nbsp;Bing Huang,&nbsp;Hongyu Han","doi":"10.1016/j.ejop.2023.126012","DOIUrl":"10.1016/j.ejop.2023.126012","url":null,"abstract":"<div><p>Coccidiosis, a serious intestinal parasitic disease caused by <em>Eimeria</em> spp<em>.</em>, can result in huge annual economic losses to the poultry industry worldwide. At present, coccidiosis is mainly controlled by anticoccidial drugs. However, drug resistance has developed in <em>Eimeria</em> because of the long-term and unreasonable use of the drugs currently available. In our previous study, RNA-seq showed that the expression of methionine aminopeptidase1 (<em>Et</em>MetAP1) was up-regulated in diclazuril-resistant (DZR) and maduramicin-resistant (MRR) strains compared to drug-sensitive (DS) strain of <em>Eimeria tenella</em>. In this study, <em>Et</em>MetAP1 was cloned and expressed, and the function and characteristics of the <em>Et</em>MetAP1 protein were analyzed. The transcription and translation levels of <em>Et</em>MetAP1 in DS strain of <em>E. tenella</em> at different developmental stages were analyzed by qPCR and western blotting. We found that the transcription and translation levels of <em>Et</em>MetAP1 in second-generation merozoites (SM) were higher than those of the other three stages (unsporulated oocyst, sporulated oocyst, and sporozoites). Simultaneously, qPCR was used to analyze the mRNA transcription levels of <em>Et</em>MetAP1 in DS, DZR, MRR, and salinomycin-resistant (SMR) strain. The results showed that compared to the sensitive strain, the transcription levels of <em>Et</em>MetAP1 in DZR and MRR were up-regulated. There was no significant difference in transcription level in SMR. Indirect immunofluorescence localization showed that the protein was mainly localised in the cell membrane and cytoplasm of sporozoites and SM. An invasion inhibition test showed that anti-r<em>Et</em>MetAP1 polyclonal antibody could effectively inhibit the sporozoite invasion of host cells. These results suggest that the protein may be involved in the growth and development of parasites in host cells, the generation of drug resistance, and host cell invasion.</p></div>","PeriodicalId":12042,"journal":{"name":"European journal of protistology","volume":"90 ","pages":"Article 126012"},"PeriodicalIF":2.9,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10264150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Three new species of Gromia (Protista, Rhizaria) identified from the Romanian Black Sea shelf","authors":"Sylvain Kreuter ,&nbsp;Maria Holzmann ,&nbsp;Diana Grace Holdsworth ,&nbsp;Rozalia Motoc ,&nbsp;Ana Bianca Pavel","doi":"10.1016/j.ejop.2023.126004","DOIUrl":"10.1016/j.ejop.2023.126004","url":null,"abstract":"<div><p><span>The protist genus </span><em>Gromia</em> was first described in 1835 by Dujardin and while gromiids are prominent in the marine environment, <em>Gromia oviformis</em> was, for a long time, the only valid species regularly recorded. To date, 16 species that are morphologically and/or genetically distinct have been described. While recent studies are documenting their diversity and their ecological importance, <em>G. oviformis</em> has been the sole gromiid species identified in the Black Sea, although unnamed <em>Gromia</em><span><span> species have also been recorded. We collected sediment samples from the Romanian continental shelf at varying depths (48 – 58 m) to study the morphological and </span>genetic diversity of gromiids in this part of the Black Sea. Three new species, </span><em>Gromia bugnae</em> sp. nov.<em>, Gromia dianae</em> sp. nov. and <em>Gromia fabi</em> sp. nov., were identified based on an integrative taxonomic approach, thus bringing the total described gromiid species to 19. Analysis of partial SSU rRNA gene sequences confirms that these are distinct species. Additionally, an undescribed species is represented by a sequence from the northern part of the Black Sea (Sevastopol, Kazachya Bay). The study provides further evidence of the diversity of gromiids in the Black Sea and underlines the importance of this little-known group in marginal seas.</p></div>","PeriodicalId":12042,"journal":{"name":"European journal of protistology","volume":"90 ","pages":"Article 126004"},"PeriodicalIF":2.9,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10210712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Silica-scaled heterotrophic protists: Rotosphaerida, Thaumatomonadida and Centroplasthelida in Arctic waters of Russia","authors":"Anna Bessudova ,&nbsp;Viktor Gabyshev ,&nbsp;Yelena V. Likhoshway","doi":"10.1016/j.ejop.2023.125975","DOIUrl":"10.1016/j.ejop.2023.125975","url":null,"abstract":"<div><p><span>Maintaining high levels of biological diversity in various ecosystems is necessary for stable functioning of the Earth's biosphere. The article describes diversity and ecology of heterotrophic siliceous protists<span> – rotosphaerids, colourless free-living thaumatomonad flagellates, and centrohelid heliozoans – in Arctic waters located of Asian Russia. Samples were collected in the mouths of the Olenyok, Yana, Indigirka, Kolyma Rivers – and small freshwater ponds near Settlement of Tiksi in Yakutia. Based on electron microscopy, 35 centrohelids (Heliozoa), 11 rotosphaerid species as well as four thaumatomonad flagellate species were found in the region. Seven species were recorded in Russia for the first time: </span></span><em>Rabdiaster multicosta</em>, <em>Rabdiaster reticulata</em>, <em>Turriplaca denticulata</em>, <em>Choanocystis</em> cf. <em>cordiformis parvula</em>, <em>Raineriophrys pteromorphos</em>, <em>Pseudoraphidocystis glutinosa</em> and <em>Pseudoraphidiophrys formosa.</em> For 43 species, the study area is the most northern location they were described. Morphological details of scales are discussed for selected species, particularly for widespread species of rotosphaerids – <em>Pinaciophora fluviatilis.</em> The literature on hydrochemical conditions was analyzed to find taxa with high sensitivity towards environmental changes. Such species could be further used for monitoring plankton, recovering evolutionary changes, and reconstructing past environments.</p></div>","PeriodicalId":12042,"journal":{"name":"European journal of protistology","volume":"90 ","pages":"Article 125975"},"PeriodicalIF":2.9,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10198592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anaerocyclidiidae fam. nov. (Oligohymenophorea, Scuticociliatia): A newly recognized major lineage of anaerobic ciliates hosting prokaryotic symbionts","authors":"Kateřina Poláková,&nbsp;William A. Bourland,&nbsp;Ivan Čepička","doi":"10.1016/j.ejop.2023.126009","DOIUrl":"10.1016/j.ejop.2023.126009","url":null,"abstract":"<div><p><span><span>The research on anaerobic ciliates, to date, has mainly been focused on representatives of obligately anaerobic classes such as Armophorea or Plagiopylea. In this study, we focus on the anaerobic representatives of the subclass Scuticociliatia, members of the class </span>Oligohymenophorea, which is mainly composed of aerobic ciliates. Until now, only a single anaerobic species, </span><em>Cyclidium porcatum</em> (here transferred to the genus <em>Anaerocyclidium</em><span><span> gen. nov.), has been described both molecularly and morphologically. Our broad sampling of anoxic sediments together with cultivation and single cell sequencing approaches have shown that scuticociliates are common and diversified in anoxic environments. Our results show that anaerobic scuticociliates represent a distinctive evolutionary lineage not closely related to the family Cyclidiidae (order Pleuronematida), as previously suggested. However, the </span>phylogenetic position of the newly recognized lineage within the subclass Scuticociliatia remains unresolved. Based on molecular and morphological data, we establish the family Anaerocyclidiidae fam. nov. to accommodate members of this clade. We further provide detailed morphological descriptions and 18S rRNA gene sequences for six new </span><em>Anaerocyclidium</em> species and significantly broaden the described diversity of anaerobic scuticociliates.</p></div>","PeriodicalId":12042,"journal":{"name":"European journal of protistology","volume":"90 ","pages":"Article 126009"},"PeriodicalIF":2.9,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10208440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Euglena gracilis: Biochemical properties of a membrane bound ecto-phosphatase activity modulated by fluoroaluminate complexes and different trophic conditions","authors":"Anita Leocadio Freitas-Mesquita ,&nbsp;Luiz Fernando Carvalho-Kelly ,&nbsp;Thaís Souza Silveira Majerowicz ,&nbsp;José Roberto Meyer-Fernandes","doi":"10.1016/j.ejop.2023.126010","DOIUrl":"10.1016/j.ejop.2023.126010","url":null,"abstract":"<div><p>The ecto-phosphatases belong to a group of enzymes closely associated with the cell surface that has its catalytic site facing the extracellular environment, where different phosphorylated substrates can be hydrolyzed. In the present work, we biochemically characterized the ecto-phosphatase activity of the freshwater microalgae <em>Euglena gracilis</em>, a model microorganism, ubiquitously distributed and resistant to several environmental stressors. The ecto-phosphatase activity is acidic, stimulated by copper and presents the following apparent kinetic parameters: <em>K</em>_m = 2.52 ± 0.12 mM <em>p</em>-NPP and <em>V</em>_max = 3.62 ± 0.06 nmol <em>p</em>-NP × h⁻¹ × 10⁶ cells. We observed that zinc, orthovanadate, molybdate, fluoride, and inorganic phosphate inhibit the ecto-phosphatase activity with different magnitudes. Fluoroaluminate complexes are also inhibitors of this ecto-phosphatase activity. They can be formed in the enzyme reaction conditions and are likely to occur in a natural environment where <em>E. gracilis</em> can be found. The ecto-phosphatase activity is constant through the culture growth phases and is negatively modulated after continuous subculturing in the dark when a shift from phototrophic to the heterotrophic metabolism is likely. The analysis of those biochemical parameters may contribute to understanding the role of <em>E. gracilis</em> ecto-phosphatase activity in natural environments.</p></div>","PeriodicalId":12042,"journal":{"name":"European journal of protistology","volume":"90 ","pages":"Article 126010"},"PeriodicalIF":2.9,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10199667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Holospora-like bacteria “Candidatus Gortzia yakutica” and Preeria caryophila: Ultrastructure, promiscuity, and biogeography of the symbionts","authors":"Sergei I. Fokin ,&nbsp;Natalia A. Lebedeva ,&nbsp;Alexey Potekhin ,&nbsp;Leandro Gammuto ,&nbsp;Giulio Petroni ,&nbsp;Valentina Serra","doi":"10.1016/j.ejop.2023.125998","DOIUrl":"10.1016/j.ejop.2023.125998","url":null,"abstract":"<div><p>Two already known representatives of <em>Holospora</em>-like bacteria, “<em>Candidatus</em> Gortzia yakutica” from <em>Paramecium putrinum</em> and <em>Preeria caryophila,</em> originally retrieved from the <em>Paramecium aurelia</em> complex, were found in new hosts: <em>Paramecium nephridiatum</em> and <em>Paramecium polycaryum</em>, respectively. In the present study, these bacteria were investigated using morphological and molecular methods. For “<em>Ca.</em> G. yakutica”, the first details of the electron microscopic structure in the main and new hosts were provided. Regarding <em>Pr. caryophila</em>, the ultrastructural description of this species was implemented by several features previously unknown, such as the so called “membrane cluster” dividing periplasm from cytoplasm and fine composition of infectious forms before and during its releasing from the infected macronucleus. The new combinations of these <em>Holospora</em>-like bacteria with ciliate hosts were discussed from biogeographical and ecological points of view. Host specificity of symbionts as a general paradigm was critically reviewed as well.</p></div>","PeriodicalId":12042,"journal":{"name":"European journal of protistology","volume":"90 ","pages":"Article 125998"},"PeriodicalIF":2.9,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10204820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Host specificity of passerine Lankesterella (Apicomplexa: Coccidia)","authors":"Ashwin Kumar Saravana Bhavan Venkatachalam ,&nbsp;Ivan Čepička ,&nbsp;Kristýna Hrazdilová ,&nbsp;Milena Svobodová","doi":"10.1016/j.ejop.2023.126007","DOIUrl":"10.1016/j.ejop.2023.126007","url":null,"abstract":"<div><p><span><em>Lankesterella</em></span><span> parasites are blood coccidians that have recently gained attention as their records in common passerine species emerge. To date, their occurrence has been molecularly confirmed in several passerine genera, mainly among members of the families Paridae and Acrocephalidae. Despite their relatively high prevalence in some host populations, their life cycles remain unclear, mosquitoes or mites being the proposed vectors. The aim of this study was to reveal </span><em>Lankesterella</em><span> host specificity, focusing mainly on parasites of tit and warbler species (families Paridae and Acrocephalidae). We have determined the 18S rRNA gene sequences of </span><em>Lankesterella</em><span> from 35 individuals belonging to eight different host species. Phylogenetic analysis revealed that passerine </span><em>Lankesterella</em> are host-specific, with specificity at the host genus or species level. Besides <span><em>Lankesterella, </em><em>Isospora</em></span> sequences were obtained from avian blood as well, pointing out the need for barcoding.</p></div>","PeriodicalId":12042,"journal":{"name":"European journal of protistology","volume":"90 ","pages":"Article 126007"},"PeriodicalIF":2.9,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10209297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to “Morphologic and molecular characterization of Apertospathula pilata n. sp., a novel freshwater spathidiid (Ciliophora Litostomatea) from Idaho USA” [Eur. J. Protistol. 89 (2023) 125990]","authors":"William Bourland","doi":"10.1016/j.ejop.2023.126011","DOIUrl":"10.1016/j.ejop.2023.126011","url":null,"abstract":"","PeriodicalId":12042,"journal":{"name":"European journal of protistology","volume":"90 ","pages":"Article 126011"},"PeriodicalIF":2.9,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10186041","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First redescription and molecular phylogeny of Trimyema claviforme Kahl, 1933 with the description of a Chinese population of Plagiopyla nasuta Stein, 1860 (Ciliophora, Plagiopylea)","authors":"Ran Li ,&nbsp;Wenbao Zhuang ,&nbsp;Xiaochen Feng ,&nbsp;Hunter N. Hines ,&nbsp;Xiaozhong Hu","doi":"10.1016/j.ejop.2023.126003","DOIUrl":"10.1016/j.ejop.2023.126003","url":null,"abstract":"<div><p><span>Ciliates belonging to the class Plagiopylea are obligate anaerobes that are often neglected due to their cryptic lifestyles, difficulty of observation, and overall under-sampling. Here, we investigate two species, namely </span><em>Trimyema claviforme</em> Kahl, 1933 and <em>Plagiopyla nasuta</em> Stein, 1860, collected in China from marine and freshwater anaerobic sediments, respectively. A complete morphological dataset, together with SSU rRNA gene sequence data were obtained and used to diagnose the species. No molecular sequencing had ever been performed on <em>Trimyema claviforme</em><span>, with its ciliature also previously unknown. Based on these novel data presented here, the ciliate is characterized by a claviform cell shape, with a size of 35–45 × 10–20 μm in vivo, 28–39 longitudinal somatic ciliary rows forming five ciliary girdles (four complete girdles and a shorter one), two dikinetids left to anterior end of oral kinety 1, and an epaulet. A Chinese population of the well-known ciliate </span><em>P. nasuta</em><span> was investigated, and morphological comparisons revealed phenotypic stability of the species. The phylogenetic<span> analyses supported previous findings about the monophyly of the families Trimyemidae and Plagiopylidae, with </span></span><em>Trimyema claviforme</em> branching off early in the genus <em>Trimyema</em>. The Chinese population of <em>P. nasuta</em> clusters together with two other populations with full support corroborating their conspecificity.</p></div>","PeriodicalId":12042,"journal":{"name":"European journal of protistology","volume":"90 ","pages":"Article 126003"},"PeriodicalIF":2.9,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10208686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}