Taxonomic Implications of Morphological Complexity Within the Testate Amoeba Genus Corythion from the Antarctic Peninsula
Publication date: Available online 3 August 2017 Source:Protist Author(s): Thomas P. Roland, Matthew J. Amesbury, David M. Wilkinson, Dan J. Charman, Peter Convey, Dominic A. Hodgson, Jessica Royles, Steffen Clauß, Eckhard Völcker Precise and sufficiently detailed morphological taxonomy is vital in biology, for example in the accurate interpretation of ecological and palaeoecological datasets, especially in polar regions, where biodiversity is poor. Testate amoebae on the Antarctic Peninsula (AP) are well-documented and variations in their population size have recently been interpreted as a proxy for microbial...
Source: Protist - August 4, 2017 Category: Molecular Biology Source Type: research
Anaeramoebidae fam. nov., a Novel Lineage of Anaerobic Amoebae and Amoeboflagellates of Uncertain Phylogenetic Position
We report discovery of a new lineage of anaerobic marine amoebae and amoeboflagellates, Anaeramoeba gen. nov., represented by six newly described species. The trophic form of Anaeramoeba spp. is an amoeba corresponding to the uncommon flabellate or flamellian morphotype − it is fan-shaped and produces an anterior, flattened hyaline zone and posterior hyaline projections. In contrast to other representatives of these morphotypes, cells of Anaeramoeba spp. possess acristate mitochondrion-related organelles associated with prokaryotic symbionts, and a large acentriolar centrosome. Surprisingly, two Anaeramoeba species form ...
Source: Protist - August 3, 2017 Category: Molecular Biology Source Type: research
Gametogenesis and Auxospore Development in the Bipolar Centric Diatom Brockmanniella brockmannii (Family Cymatosiraceae)
We examined gametogenesis and auxospore development in the cymatosiroid diatom Brockmanniella brockmannii. Our mating experiments demonstrated that the clones were homothallic, self-compatible, produced two eggs per oogonium and four hologenous uniflagellate male gametes per spermatogonium. Auxospores grew free in the culture medium and the most external layer of the auxospore wall was made up of spinescent scaly elements in their early globular stage of development. The anisodiametric expansion of the globular auxospore was rather limited, at best proceeding only to a sub-globular stage. Our data suggest that the initial ...
Source: Protist - July 21, 2017 Category: Molecular Biology Source Type: research
Diversification and Phylogenetics of Mobilid Peritrichs (Ciliophora)with Description of Urceolaria parakorscheltisp. nov.
Publication date: Available online 14 July 2017 Source:Protist Author(s): Nicholas A.T. Irwin, Mona Sabetrasekh, Denis H. Lynn Ciliates within the order Mobilida comprise a group of ectosymbionts that form ecologically and economically important symbioses with aquatic organisms. However, despite their significance, the factors driving mobilid diversification are poorly understood. To address this, we sought to examine the genetic diversity of two mobilid families, the trichodinids and urceolariids, over geographical areas and from different hosts. To this end we collected and provide morphological and molecular charac...
Source: Protist - July 15, 2017 Category: Molecular Biology Source Type: research
Variation in Basal Body Localisation and Targeting of Trypanosome RP2 and FOR20 Proteins
Publication date: Available online 13 July 2017 Source:Protist Author(s): Jane Harmer, Xin Qi, Gabriella Toniolo, Aysha Patel, Hannah Shaw, Fiona E. Benson, Michael L. Ginger, Paul G. McKean TOF-LisH-PLL motifs defines FOP family proteins; some members are involved in flagellum assembly. The critical role of FOP family protein FOR20 is poorly understood. Here, we report relative localisations of the four FOP family proteins in parasitic Trypanosoma brucei: TbRP2, TbOFD1 and TbFOP/FOP1-like are mature basal body proteins whereas TbFOR20 is present on pro- and mature basal bodies − on the latter it localises dist...
Source: Protist - July 14, 2017 Category: Molecular Biology Source Type: research
Maullinia braseltonii sp. nov. (Rhizaria, Phytomyxea, Phagomyxida): A Cyst-forming Parasite of the Bull Kelp Durvillaea spp. (Stramenopila, Phaeophyceae, Fucales)
Publication date: Available online 13 July 2017 Source:Protist Author(s): Pedro Murúa, Franz Goecke, Renato Westermeier, Pieter van West, Frithjof C. Küpper, Sigrid Neuhauser Phytomyxea are obligate endoparasites of angiosperm plants and Stramenopiles characterised by a complex life cycle. Here Maullinia braseltonii sp. nov., an obligate parasite infecting the bull kelp Durvillaea (Phaeophyceae, Fucales) from the South-Eastern Pacific (Central Chile and Chiloe Island) and South-Western Atlantic (Falkland Islands, UK) is described. M. braseltonii causes distinct hypertrophies (galls) on the host thalli making it e...
Source: Protist - July 14, 2017 Category: Molecular Biology Source Type: research
Pseudophyllomitus vesiculosus (Larsen and Patterson 1990) Lee, 2002, a Poorly Studied Phagotrophic Biflagellate is the First Characterized Member of Stramenopile Environmental Clade MAST-6
In this study, we established a culture of Pseudophyllomitus vesiculosus, which is a poorly studied phagotrophic flagellate of uncertain taxonomic position. Our molecular phylogenetic analyses based on small subunit ribosomal RNA gene sequences robustly supported the inclusion of P. vesiculosus in the MAST-6 clade. Our microscopic observations indicated that P. vesiculosus shared characteristics with stramenopiles, including an anterior flagellum that exhibits sinusoidal waves and bears tubular mastigonemes. The flagellar apparatus of P. vesiculosus was also similar to that of other stramenopiles in having a transitional h...
Source: Protist - July 7, 2017 Category: Molecular Biology Source Type: research
Molecular Evidence of Apatococcus, including A. fuscideae sp. nov., as Photobiont in the Genus Fuscidea
Publication date: Available online 29 June 2017 Source:Protist Author(s): Martina Zahradníková, Heidi L. Andersen, Tor Tønsberg, Andreas Beck The knowledge of the taxonomy and classification of algae (including lichenized) has recently increased rapidly, but there are still many gaps. We aimed to 1) identify the Fuscidea photobionts by locating their taxonomic positions in the green algal classification, and 2) to resolve their interspecific relationships. The lichenized algae were examined based on morphological observations of axenic isolates as well as molecular studies of 18S and ITS nrDNA sequences. Analysis ...
Source: Protist - June 30, 2017 Category: Molecular Biology Source Type: research
Identification of Pelomyxa palustris endosymbionts
Publication date: Available online 23 June 2017 Source:Protist Author(s): Gabriel Gutiérrez, Ludmila V. Chistyakova, Eduardo Villalobo, Alexei Y. Kostygov, Alexander O. Frolov Pelomyxa palustris is a giant anaerobic/microaerobic amoeba, characterized by a number of exceptional cytological and physiological features, among them the presumed absence of energy producing organelles and the presence of endosymbiotic bacteria. These endosymbionts have been previously distinguished as: a large rectangular-shaped Gram-variable rod with a central cleft; a slender Gram-negative rod; and a slender Gram-positive rod. Using DNA...
Source: Protist - June 24, 2017 Category: Molecular Biology Source Type: research
A New Parasitic Chytrid, Staurastromyces oculus (Rhizophydiales, Staurastromycetaceae fam. nov.), Infecting the Freshwater Desmid Staurastrum sp.
Publication date: Available online 13 May 2017 Source:Protist Author(s): Silke Van den Wyngaert, Kensuke Seto, Keilor Rojas-Jimenez, Maiko Kagami, Hans-Peter Grossart Chytrids are a diverse group of ubiquitous true zoosporic fungi. The recent molecular discovery of a large diversity of undescribed chytrids has raised awareness on their important, but so far understudied ecological role in aquatic ecosystems. In the pelagic zone, of both freshwater and marine ecosystems, many chytrid species have been morphologically described as parasites on almost all major groups of phytoplankton. However, the majority of these pa...
Source: Protist - May 13, 2017 Category: Molecular Biology Source Type: research
A Comparison of Methods to Analyze Aquatic Heterotrophic Flagellates of Different Taxonomic Groups
Publication date: Available online 9 May 2017 Source:Protist Author(s): Alexandra Jeuck, Frank Nitsche, Claudia Wylezich, Olaf Wirth, Tanja Bergfeld, Fabienne Brutscher, Melanie Hennemann, Shahla Monir, Anja Scherwaß, Nicole Troll, Hartmut Arndt Heterotrophic flagellates contribute significantly to the matter flux in aquatic and terrestrial ecosystems. Still today their quantification and taxonomic classification bear several problems in field studies, though these methodological problems seem to be increasingly ignored in current ecological studies. Here we describe and test different methods, the live-count...
Source: Protist - May 10, 2017 Category: Molecular Biology Source Type: research
Evolutionary Relationship of the Scale-Bearing Kraken (incertae sedis, Monadofilosa, Cercozoa, Rhizaria): Combining Ultrastructure Data and a Two-Gene Phylogeny
In this study, K. carinae has been studied by electron microscopy, these data conjoined with a two-gene phylogeny were used to give more insight into the evolutionary relationship of the genus Kraken within Cercozoa. The data confirmed the absence of flagella, but also showed novel characteristics, such as the presence of extrusomes, osmiophilic bodies, and mitochondria with flat cristae. Surprising was the presence of single-tier scales which are carried by cell outgrowths, much of what is expected of the last common ancestor of the class Imbricatea. The phylogenetic analyses however confirmed previous results, indicating...
Source: Protist - May 10, 2017 Category: Molecular Biology Source Type: research
Polyphyly in the Thecate Amoeba Genus Lecythium (Chlamydophryidae, Tectofilosida, Cercozoa), Redescription of its Type Species L. hyalinum, Description of L. jennyae sp. nov. and the Establishment of Fisculla gen. nov. and Fiscullidae fam. nov.
In this study, we screened for L. hyalinum in freshwater samples of Germany and the Netherlands. Four different isolates of L. hyalinum and one novel species were cultured and characterized by light microscopy. Phylogenetic analyses based on the small ribosomal subunit (SSU) RNA gene show that the genus Lecythium forms two robust clades, one forming a sister group to the Rhizaspididae/Pseudodifflugiidae clade (Tectofilosida), the other branching within ‘Novel Clade 4' (Tectofilosida). We untangle this polyphyly by establishing Fisculla gen. nov. and the Fiscullidae fam. nov. for the former of these two clades. (Source: Protist)
Source: Protist - May 2, 2017 Category: Molecular Biology Source Type: research
Soil DNA Extraction Procedure Influences Protist 18S rRNA Gene Community Profiling Outcome
We examined the effect of three acknowledged DNA recovery methods, two manual methods (ISOm-11063, GnS-GII) and one commercial kit (MoBio), on soil protist community structures obtained from different sites with different land uses. Results from 18S rRNA gene amplicon sequencing suggest that DNA extraction method significantly affect the replicate homogeneity, the total number of operational taxonomic units (OTUs) recovered and the overall taxonomic structure and diversity of soil protist communities. However, DNA extraction effects did not overwhelm the natural variation among samples, as the community data still strongly...
Source: Protist - May 2, 2017 Category: Molecular Biology Source Type: research
The Central Vacuole of the Diatom Phaeodactylum tricornutum: Identification of New Vacuolar Membrane Proteins and of a Functional Di-leucine-based Targeting Motif
Publication date: Available online 15 March 2017 Source:Protist Author(s): Viktoria Schreiber, Josefine Dersch, Katharina Puzik, Oliver Bäcker, Xiaojuan Liu, Simone Stork, Julian Schulz, Thomas Heimerl, Andreas Klingl, Stefan Zauner, Uwe G. Maier Diatoms are unicellular organisms evolved by secondary endosymbiosis. Although studied in many aspects, the functions of vacuolar-like structures of these organisms are rarely investigated. One of these structures is a dominant central vacuole-like compartment with a marbled phenotype, which is supposed to represent a chrysolaminarin-storing and carbohydrate mobiliza...
Source: Protist - May 2, 2017 Category: Molecular Biology Source Type: research
