Journal of Eukaryotic Microbiology最新文献

{"title":"Morphology, behavior, and phylogenomics of Oxytoxum lohmannii, Dinoflagellata.","authors":"Elizabeth C Cooney, Dean M Jacobson, Gordon V Wolfe, Kelley J Bright, Juan F Saldarriaga, Patrick J Keeling, Brian S Leander, Suzanne L Strom","doi":"10.1111/jeu.13050","DOIUrl":"https://doi.org/10.1111/jeu.13050","url":null,"abstract":"<p><p>Dinoflagellates are an abundant and diverse group of protists representing a wealth of unique biology and ecology. While many dinoflagellates are photosynthetic or mixotrophic, many taxa are heterotrophs, often with complex feeding strategies. Compared to their photosynthetic counterparts, heterotrophic dinoflagellates remain understudied, as they are difficult to culture. One exception, a long-cultured isolate originally classified as Amphidinium but recently reclassified as Oxytoxum, has been the subject of a number of feeding, growth, and chemosensory studies. This lineage was recently determined to be closely related to Prorocentrum using phylogenetics of ribosomal RNA gene sequences, but the exact nature of this relationship remains unresolved. Using transcriptomes sequenced from culture and three single cells from the environment, we produce a robust phylogeny of 242 genes, revealing Oxytoxum is likely sister to the Prorocentrum clade, rather than nested within it. Molecular investigations uncover evidence of a reduced, nonphotosynthetic plastid and proteorhodopsin, a photoactive proton pump acquired horizontally from bacteria. We describe the ultrastructure of O. lohmannii, including densely packed trichocysts, and a new type of mucocyst. We observe that O. lohmannii feeds preferentially on cryptophytes using myzocytosis, but can also feed on various phytoflagellates using conventional phagocytosis. O. lohmannii is amenable to culture, providing an opportunity to better study heterotrophic dinoflagellate biology and feeding ecology.</p>","PeriodicalId":15672,"journal":{"name":"Journal of Eukaryotic Microbiology","volume":" ","pages":"e13050"},"PeriodicalIF":2.1,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141633600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New insights into Microsporidia polar tube function and invasion mechanism","authors":"Maurine Fayet,&nbsp;Mengxian Long,&nbsp;Bing Han,&nbsp;Abdel Belkorchia,&nbsp;Frédéric Delbac,&nbsp;Valerie Polonais","doi":"10.1111/jeu.13043","DOIUrl":"10.1111/jeu.13043","url":null,"abstract":"<p>Microsporidia comprise a large phylum of single-cell and obligate intracellular parasites that can infect a wide range of invertebrate and vertebrate hosts including humans. These fungal-related parasites are characterized by a highly reduced genome, a strong energy dependence on their host, but also by their unique invasion organelle known as the polar tube which is coiled within the resistant spore. Upon appropriate environmental stimulation, the long hollow polar tube (ranging from 50 to 500 μm in length) is extruded at ultra-fast speeds (300 μm/s) from the spore acting as a harpoon-like organelle to transport and deliver the infectious material or sporoplasm into the host cell. To date, seven polar tube proteins (PTPs) with distinct localizations along the extruded polar tube have been described. For example, the specific location of PTP4 and PTP7 at the tip of the polar tube supports their role in interacting with cellular receptor(s). This chapter provides a brief overview on the current understanding of polar tube structure and dynamics of extrusion, primarily through recent advancements in cryo-tomography and 3D reconstruction. It also explores the various mechanisms used for host cell invasion. Finally, recent studies on the structure and maturation of sporoplasm and its moving through the tube are discussed.</p>","PeriodicalId":15672,"journal":{"name":"Journal of Eukaryotic Microbiology","volume":"71 5","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141554871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Morphological and molecular characterization of Eimeria magna infecting local rabbit (Oryctolagus cuniculus) in Alkarg City, Saudi Arabia.","authors":"Mutee Murshed, Mohammed Mares, Hossam M A Aljawdah, Osama B Mohammed, Saleh Al-Quraishy","doi":"10.1111/jeu.13044","DOIUrl":"https://doi.org/10.1111/jeu.13044","url":null,"abstract":"<p><p>Coccidiosis is one of the most prevalent diseases found in local rabbits (Oryctolagus cuniculus), which is caused by the Eimeria. The study aimed to more reliably identify Eimeria species (Eimeria magna) infecting Local Rabbits in Alkarg City, Saudi Arabia, based the method on the molecular properties and morphological and molecular biological techniques. Sub-spheroidal oocysts measuring 21-27 × 12-16 (24 × 14.4) μm (20 n) and with a length/width (L/W) ratio of 0.9-1.1 (1.0) were identified by microscopic analysis of a fecal sample. Oocysts feature a bi-layered wall that is 1.0-1.2 (1.1) μm thick. About two-thirds of the wall's thickness is made up of a smooth outer layer. A polar granule is present, but neither a micropyle nor an oocyst residuum is present. The ovoidal sporozoites measure 15-18 × 8-11 (16.5 × 9.5) μm, have an L/W ratio of 1.6-1.8 (1.7), and take up around 21% of the oocyst's total surface. The mean size of the sub-Stieda body is 1.4 × 2.3 μm, while the average size of the Stieda body is 0.9 × 1.8 μm. The para-Stieda body is lacking. Sporocyst residuum appears membrane-bound and has an uneven form made up of several granules. With two refractile bodies below the striations and pronounced striations at the more pointed end, sporozoites are vermiform, measuring an average of 11.6 × 4.0 μm. The results of the sequencing for the 18S rDNA gene confirmed the species of Eimeria parasites found in the host (rabbits). The current parasite species is closely related to the previously described and deposited E. magna and deeply embedded in the genus Eimeria (family Eimeriidae). According to the findings, single oocyst molecular identification of Eimeria may be accomplished through consistent use of the morphological and molecular results. It is possible to draw the conclusion that the current research supplies relevant facts that help assess the potential infection and future control measures against rabbit coccidiosis to reduce the financial losses that can be incurred by the rabbit industry in Saudi Arabia.</p>","PeriodicalId":15672,"journal":{"name":"Journal of Eukaryotic Microbiology","volume":" ","pages":"e13044"},"PeriodicalIF":2.1,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141498207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Review of Pseudoloma neurophilia (Microsporidia): A common neural parasite of laboratory zebrafish (Danio rerio)","authors":"Corbin J. Schuster,&nbsp;Katrina N. Murray,&nbsp;Justin L. Sanders,&nbsp;Claire E. Couch,&nbsp;Michael L. Kent","doi":"10.1111/jeu.13040","DOIUrl":"10.1111/jeu.13040","url":null,"abstract":"<p>Zebrafish (<i>Danio rerio</i>) is now the second most used animal model in biomedical research. As with other vertebrate models, underlying diseases and infections often impact research. Beyond mortality and morbidity, these conditions can compromise research end points by producing nonprotocol induced variation within experiments. <i>Pseudoloma neurophilia</i>, a microsporidium that targets the central nervous system, is the most frequently diagnosed pathogen in zebrafish facilities. The parasite undergoes direct, horizontal transmission within populations, and is also maternally transmitted with spores in ovarian fluid and occasionally within eggs. This transmission explains the wide distribution among research laboratories as new lines are generally introduced as embryos. The infection is chronic, and fish apparently never recover following the initial infection. However, most fish do not exhibit outward clinical signs. Histologically, the parasite occurs as aggregates of spores throughout the midbrain and spinal cord and extends to nerve roots. It often elicits meninxitis, myositis, and myodegeneration when it infects the muscle. There are currently no described therapies for the parasite, thus the infection is best avoided by screening with PCR-based tests and removal of infected fish from a facility. Examples of research impacts include reduced fecundity, behavioral changes, transcriptome alterations, and autofluorescent lesions.</p>","PeriodicalId":15672,"journal":{"name":"Journal of Eukaryotic Microbiology","volume":"71 5","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141498208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prorocentrum canariense sp. nov., a case of pseudo-cryptic speciation in the cosmopolitan dinoflagellate P. compressum (Prorocentrales, Dinophyceae)","authors":"Fernando Gómez,&nbsp;Antera Martel Quintana,&nbsp;Eduvigis Rodríguez Coello,&nbsp;Eugenio Raymond,&nbsp;Rafael Salas,&nbsp;Jillian F. McClimon,&nbsp;Juan Luis Gómez Pinchetti","doi":"10.1111/jeu.13039","DOIUrl":"10.1111/jeu.13039","url":null,"abstract":"<p>The planktonic dinoflagellate <i>Prorocentrum compressum</i> is widespread in warm and temperate seas. A strain identified as <i>P</i>. cf. <i>compressum</i> BEA 0681B isolated from the island of Gran Canaria, NE Atlantic Ocean, showed a divergence in rDNA/ITS phylogenies with respect to <i>P</i>. <i>compressum</i>. The Canarian strain was oval, with an average length-to-width ratio of 1.35, smooth thecal surface with less than 150 thecal pores, including oblique pores, sometimes with a bifurcated opening. In contrast, <i>P</i>. <i>compressum</i> was rounder, with a length-to-width ratio &lt; 1.2, with reticulate-foveate ornamentation and 200–300 pores per valve. We propose <i>Prorocentrum canariense</i> sp. nov. These species clustered as the most early-branching lineage in the clade <i>Prorocentrum</i> sensu stricto. Although this clade mainly contains planktonic species, the closer relatives were the benthic species <i>P</i>. <i>tsawwassenense</i> and <i>P</i>. <i>elegans</i>. Interestingly, <i>P</i>. <i>compressum</i> and <i>P</i>. <i>canariense</i> sp. nov. are widely distributed in temperate and warm seas without an apparent morphological adaptation to planktonic life. The formation of two concentric hyaline mucilaginous walls could contribute to this success. We discuss the use of <i>Prorocentrum bidens</i> to solve the nomenclature issue of <i>P</i>. <i>compressum</i> that was described citing a diatom as basionym.</p>","PeriodicalId":15672,"journal":{"name":"Journal of Eukaryotic Microbiology","volume":"71 4","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141492218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Functional stress responses in Glaucophyta: Evidence of ethylene and abscisic acid functions in Cyanophora paradoxa.","authors":"Baptiste Genot, Margaret Grogan, Matthew Yost, Gabriella Iacono, Stephen D Archer, John A Burns","doi":"10.1111/jeu.13041","DOIUrl":"https://doi.org/10.1111/jeu.13041","url":null,"abstract":"<p><p>Glaucophytes, an enigmatic group of freshwater algae, occupy a pivotal position within the Archaeplastida, providing insights into the early evolutionary history of plastids and their host cells. These algae possess unique plastids, known as cyanelles that retain certain ancestral features, enabling a better understanding of the plastid transition from cyanobacteria. In this study, we investigated the role of ethylene, a potent hormone used by land plants to coordinate stress responses, in the glaucophyte alga Cyanophora paradoxa. We demonstrate that C. paradoxa produces gaseous ethylene when supplied with exogenous 1-aminocyclopropane-1-carboxylic acid (ACC), the ethylene precursor in land plants. In addition, we show that cells produce ethylene natively in response to abiotic stress, and that another plant hormone, abscisic acid (ABA), interferes with ethylene synthesis from exogenously supplied ACC, while positively regulating reactive oxygen species (ROS) accumulation. ROS synthesis also occurred following abiotic stress and ACC treatment, possibly acting as a second messenger in stress responses. A physiological response of C. paradoxa to ACC treatment is growth inhibition. Using transcriptomics, we reveal that ACC treatment induces the upregulation of senescence-associated proteases, consistent with the observation of growth inhibition. This is the first report of hormone usage in a glaucophyte alga, extending our understanding of hormone-mediated stress response coordination into the Glaucophyta, with implications for the evolution of signaling modalities across Archaeplastida.</p>","PeriodicalId":15672,"journal":{"name":"Journal of Eukaryotic Microbiology","volume":" ","pages":"e13041"},"PeriodicalIF":2.1,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141476676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Past-President address: My journey in microbial ecology—footprints in the sand, island hopping, supply chains, and technology bridges","authors":"Gaytha A. Langlois","doi":"10.1111/jeu.13037","DOIUrl":"10.1111/jeu.13037","url":null,"abstract":"<p>This paper highlights and honors the connectivity among protistan researchers, using my own research journey as a backdrop, with attention to the supply chain of ideas, supporters, and other influencers who helped to shape and guide my career by sharing their ideas, protocols, skills, and enthusiasm. In looking back at the journey, the supply chain in my career has also included changes in the conceptual framework for my research studies, converging with a continuous flow of ideas and support from colleagues and mentors. To illustrate the complex map of ideas and supporters, this paper will examine technological advances, paradigm shifts in ecological constructs, geographical considerations, breakthroughs in peritrich biology, and the importance of an integrated perspective as we navigate the changing realities of today's scientific challenges.</p>","PeriodicalId":15672,"journal":{"name":"Journal of Eukaryotic Microbiology","volume":"71 4","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141468501","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Letter from the Editor","authors":"Roberto Docampo","doi":"10.1111/jeu.13042","DOIUrl":"10.1111/jeu.13042","url":null,"abstract":"","PeriodicalId":15672,"journal":{"name":"Journal of Eukaryotic Microbiology","volume":"71 4","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141468500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"How to overcome constraints imposed by microsporidian genome features to ensure gene prediction?","authors":"Eric Peyretaillade,&nbsp;Reginal F. Akossi,&nbsp;Jérémy Tournayre,&nbsp;Frédéric Delbac,&nbsp;Ivan Wawrzyniak","doi":"10.1111/jeu.13038","DOIUrl":"10.1111/jeu.13038","url":null,"abstract":"<p>Since the advent of sequencing techniques and due to their continuous evolution, it has become easier and less expensive to obtain the complete genome sequence of any organism. Nevertheless, to elucidate all biological processes governing organism development, quality annotation is essential. In genome annotation, predicting gene structure is one of the most important and captivating challenges for computational biology. This aspect of annotation requires continual optimization, particularly for genomes as unusual as those of microsporidia. Indeed, this group of fungal-related parasites exhibits specific features (highly reduced gene sizes, sequences with high rate of evolution) linked to their evolution as intracellular parasites, requiring the implementation of specific annotation approaches to consider all these features. This review aimed to outline these characteristics and to assess the increasingly efficient approaches and tools that have enhanced the accuracy of gene prediction for microsporidia, both in terms of sensitivity and specificity. Subsequently, a final part will be dedicated to postgenomic approaches aimed at reinforcing the annotation data generated by prediction software. These approaches include the characterization of other understudied genes, such as those encoding regulatory noncoding RNAs or very small proteins, which also play crucial roles in the life cycle of these microorganisms.</p>","PeriodicalId":15672,"journal":{"name":"Journal of Eukaryotic Microbiology","volume":"71 5","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141457348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Updated classification of the phylum Parabasalia","authors":"Vittorio Boscaro,&nbsp;Erick R. James,&nbsp;Rebecca Fiorito,&nbsp;Javier del Campo,&nbsp;Rudolf H. Scheffrahn,&nbsp;Patrick J. Keeling","doi":"10.1111/jeu.13035","DOIUrl":"10.1111/jeu.13035","url":null,"abstract":"<p>The phylum Parabasalia includes very diverse single-cell organisms that nevertheless share a distinctive set of morphological traits. Most are harmless or beneficial gut symbionts of animals, but some have turned into parasites in other body compartments, the most notorious example being <i>Trichomonas vaginalis</i> in humans. Parabasalians have garnered attention for their nutritional symbioses with termites, their modified anaerobic mitochondria (hydrogenosomes), their character evolution, and the wholly unique features of some species. The molecular revolution confirmed the monophyly of Parabasalia, but considerably changed our view of their internal relationships, prompting a comprehensive reclassification 14 years ago. This classification has remained authoritative for many subgroups despite a greatly expanded pool of available data, but the large number of species and sequences that have since come out allow for taxonomic refinements in certain lineages, which we undertake here. We aimed to introduce as little disruption as possible but at the same time ensure that most taxa are truly monophyletic, and that the larger clades are subdivided into meaningful units. In doing so, we also highlighted correlations between the phylogeny of parabasalians and that of their hosts.</p>","PeriodicalId":15672,"journal":{"name":"Journal of Eukaryotic Microbiology","volume":"71 4","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jeu.13035","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141198981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}