Biodiversity of freshwater ciliates (Protista, Ciliophora) in the Lake Weishan Wetland, China: the state of the art

Marine Life Science & Technology, Journal Year: 2022, Volume and Issue: 4(4), P. 429 - 451

Published: Nov. 28, 2022

Language: Английский

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Morphological and molecular examination of the ciliate family Lagynusidae (Protista, Ciliophora, Prostomatea) with descriptions of two new genera and two new species from China

Marine Life Science & Technology, Journal Year: 2023, Volume and Issue: 5(2), P. 178 - 195

Published: May 29, 2023

Ciliates in the class Prostomatea play an important role global microbial loop due to their significant abundances and broad feeding strategies at foundation of food webs. Despite importance ecosystems, taxonomy systematics this group ciliates has long been poorly understood, with being especially true for members family Lagynusidae. Here we examine four lagynusids collected from sandy beaches China, using silver-staining 18S rRNA gene sequencing techniques. These investigations revealed two new genera species provided details little known forms: Penardella marina gen. nov., sp. Apolagynus cucumis (as reported by Penard. Études sur les infusoires d'eau douce. Georg Cie, Genève, 1922) comb. Lagynus minutus elegans (Engelmann Z Wiss Zool 11:347-393, 1862) Quennerstedt (Acta Univ Lund 4:1-48, 1867). nov. can be morphologically distinguished having more than three dikinetidal perioral kineties. differs closely related genus absence a conspicuous neck-like region. The ciliature is here first time, which demonstrates classification within Furthermore, binucleatus (Jiang et al., 2021) established according finding. results our phylogenetic analyses based on support establishment indicate that Lagynusidae monophyletic, further strengthens its valid taxonomic status.

Language: Английский

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Re-evaluation of the systematic position of the order Prostomatida (Protista: Ciliophora), with the establishment of two new genera and two new species

Zoological Journal of the Linnean Society, Journal Year: 2023, Volume and Issue: 200(4), P. 849 - 864

Published: Sept. 28, 2023

Abstract Prostomatean ciliates inhabit a wide range of aquatic environments and serve as trophic link in food webs. However, the biodiversity molecular phylogeny Prostomatea, especially order Prostomatida, is poorly known owing to undersampling paucity data. Here, three prostomatid ciliates, Platina marina gen. nov., sp. Parametacystis pulchra nov. Apsiktrata gracilis, were studied based on morphological data small subunit ribosomal ribonucleic acid (SSU rRNA) gene sequences. The two new genera show close relationship with class Plagiopylea but distant Metacystis, which bears strong similarity genera. simplified oral ciliature can be regarded synapomorphy SSU rRNA representative family Apsiktratidae was sequenced for first time. Morphological phylogenetic analyses suggest that might more closely related Prorodontida than basket phylogenetically informative brosse distinguishing Prostomatida. Supplementation rare taxa reveals association between Prostomatida Trimyemidae. putative secondary structure V9 region suggests sister Plagiopylea.

Language: Английский

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Diverse winter communities and biogeochemical cycling potential in the under-ice microbial plankton of a subarctic river-to-sea continuum

Microbiology Spectrum, Journal Year: 2024, Volume and Issue: 12(5)

Published: March 21, 2024

ABSTRACT Winter conditions greatly alter the limnological properties of lotic ecosystems and availability nutrients, carbon, energy resources for microbial processes. However, composition metabolic capabilities winter communities are still largely uncharacterized. Here, we sampled under-ice microbiome Great Whale River (Nunavik, Canada) its discharge plume into Hudson Bay. We used a combination 16S 18S rRNA gene amplicon analysis metagenomic sequencing to evaluate size-fractionated functional potential plankton. These were diverse in taxonomic metabolically versatile terms carbon acquisition, including capacity carry out phototrophic processes degrade aromatic organic matter. Limnological properties, community composition, differed between shallow deeper sites river, fresh brackish water vertical profile plume. Community also varied by size fraction, with greater richness prokaryotes larger fraction (>3 µm) eukaryotes smaller (0.22–3 µm). The freshwater included cosmopolitan bacterial genera that previously detected summer, indicating their persistence over time wide range physico-chemical conditions. observations imply subarctic rivers associated plumes retain broad diversity throughout year processing complex terrestrial materials persists beneath ice during long season. IMPORTANCE Microbiomes vary multiple timescales, short- long-term changes environment. there is scarcity data understanding about structure functioning aquatic relative summer. This especially case seasonally ice-covered rivers, limiting our these common boreal, subpolar, polar regions. examined Canadian river entry sea characterize features community. found substantial both capabilities, compounds, despite constraints imposed prolonged seasonal ice-cover near-freezing temperatures. study indicates ecological complexity importance microbiomes coastal marine environment they into.

Language: Английский

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The planktonic freshwater ciliate Balanion planctonicum (Ciliophora, Prostomatea): A cryptic species complex or a “complex species”?

Journal of Eukaryotic Microbiology, Journal Year: 2025, Volume and Issue: 72(1)

Published: Jan. 1, 2025

Abstract The globally distributed ciliate Balanion planctonicum is a primary consumer of phytoplankton spring blooms. Due to its small size (~20 μm), identification and quantification by molecular tools preferable as an alternative the laborious counting specimen in quantitative protargol stains. However, previous sequencing 18S rDNA V9 region B. from Lake Zurich (Switzerland) subsequent fluorescence situ hybridization yielded significantly lower cell numbers than using morphotype counting. This raised question whether shows cryptic diversity or it just ‘complex species’ with intra‐clonal polymorphisms. Over three years, we established numerous monoclonal cultures, long‐read operons revealed four distinct dominant haplotypes (BpHs 1–4). gene sequences BpHs 1 3 differed 6% did not share polymorphisms, providing evidence for two clades. Furthermore, phylogenetic analyses corroborate sister relationship between Askenasia (plus Hexasterias Radiosperma ). Morphologically, clades are nearly indistinguishable differences macronucleus length width ratio. CARD‐FISH indicated that even more extensive still unidentified

Language: Английский

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Internal Transcribed Spacers Enable Species-Level Metataxonomic Analysis of Ciliated Protozoa

ISME Communications, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 11, 2025

Traditional morphology-based ciliate classification is often time-consuming and inaccurate, necessitating molecular approaches. Although 18S rRNA gene sequencing widely used for taxonomic analyses of ciliates, its high degree conservation makes it challenging to achieve species-level resolution. This study explores the potential internal transcribed spacers (ITS1 ITS2) 28S improve resolution beyond that offered by in free-living host-associated ciliates. A comparative analysis ITS, 18S, sequences retrieved from public databases indicated ITS regions exhibit greater inter- intra-specific sequence dissimilarity compared gene, supporting existing literature. We then designed universal primers targeting freshwater rumen These were rigorously evaluated their inclusiveness, specificity, amplification efficiency using in-silico PCR, experimental followed metataxonomic communities. In-silico revealed inclusiveness exceeding 80%, while validated specificity. Metataxonomic ciliates demonstrated captured significantly diversity than gene. Also, ITS1 superior detecting most species went unnoticed findings underscore superiority ITS1, a lesser extent ITS2, as markers enhancing recommend an alternative marker overcome limitations gene-based approaches taxonomy.

Language: Английский

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Morphological diversity and molecular phylogeny of five Paramecium bursaria (Alveolata, Ciliophora, Oligohymenophorea) syngens and the identification of their green algal endosymbionts

Scientific Reports, Journal Year: 2022, Volume and Issue: 12(1)

Published: Oct. 27, 2022

Abstract Paramecium bursaria is a mixotrophic ciliate species, which common in stagnant and slow-flowing, nutrient-rich waters. It usually found living symbiosis with zoochlorellae (green algae) of the genera Chlorella or Micractinium . We investigated P. isolates from around world, some have already been extensively studied various laboratories, but whose morphological genetic identity has not yet completely clarified. Phylogenetic analyses SSU ITS rDNA sequences revealed five highly supported lineages, corresponded to syngen most likely biological species assignment. These syngens R1–R5 could also be distinguished by unique synapomorphies secondary structures ITS. Considering these synapomorphies, we clearly assign existing GenBank entries specific syngens. In addition, discovered at amino acids COI gene for identification Using metadata entries, showed worldwide distribution, however, R1 R5 were only Europe. From morphology, did show any significant deviations. The strains had either variabilis , vulgaris conductrix as endosymbionts.

Language: Английский

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Using digital PCR to predict ciliate abundance from ribosomal RNA gene copy numbers

Environmental Microbiology, Journal Year: 2024, Volume and Issue: 26(4)

Published: April 1, 2024

Abstract Ciliates play a key role in most ecosystems. Their abundance natural samples is crucial for answering many ecological questions. Traditional methods of quantifying individual species, which rely on microscopy, are often labour‐intensive, time‐consuming and can be highly biassed. As result, we investigated the potential digital polymerase chain reaction (dPCR) ciliates. A significant challenge this process high variation copy number taxonomic marker gene (ribosomal RNA [rRNA]). We first quantified rRNA numbers (GCN) model ciliate, Paramecium tetraurelia , during different stages cell cycle growth phases. The per‐cell GCN varied between approximately 11,000 130,000, averaging around 50,000 copies per cell. Despite these variations GCN, found correlation numbers. This likely due to coexistence cellular an uncontrolled (environmental) ciliate population. Thanks sensitivity dPCR, were able detect target sample that contained only single dPCR approach presented here valuable addition molecular toolbox protistan ecology. It may guide future studies monitoring targeted (even rare) ciliates samples.

Language: Английский

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Thermal response of freshwater ciliates: Can they survive at elevated lake temperatures?

Freshwater Biology, Journal Year: 2024, Volume and Issue: 69(9), P. 1245 - 1260

Published: July 18, 2024

Abstract Ciliates are a well‐defined, species‐rich, versatile group of heterotrophic and mixotrophic protists. Their response to increased temperature during global warming is critical for the structure functioning freshwater food webs. I conducted meta‐analysis literature from field studies experimental evidence assess parameters characterising thermal ciliates. The shape performance curve predicts ciliates' survival at supraoptimal temperatures (i.e., width safety margin). typical margin c. 5°C. More than two‐thirds ciliates dwelling permanently or occasionally in pelagial cannot survive exceeding 30°C. Likewise, cold‐stenothermic species, which represent significant fraction euplanktonic ciliates, by evolutionary adaptation rapidly environments. statistical analysis revealed that affected their planktonic lifestyle (euplanktonic vs. tychoplanktonic), ability form cysts nutritional ecology. Bactivorous have widest niche, algivorous narrowest niche. Phenotypic plasticity genetic variation, favouring selection pre‐adapted species new environment, widespread among However, lack optima imprecisely defined tolerance limits most hampers present analysis. extent acclimation requires further research with more ciliate few chosen thus far. Recent eco‐evolutionary work modelling approaches demonstrated responses follow general trends predicted metabolic theory ecology mechanistic functions inherent enzyme kinetics. identified current knowledge gaps avenues future may serve as model study other biota. Thermal conflict stressors (predators, availability, pH), making predictions on role warmer environment difficult, if not impossible, present.

Language: Английский

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Internal Transcribed Spacers as Phylogenetic Markers Enable Species-level Metataxonomic Analysis of Ciliated Protozoa

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Feb. 7, 2024

Abstract Background The conventional morphology-based classification of ciliates is often inaccurate and time-consuming. To address this issue, sequencing, analysis the 18S rRNA gene have been used as an alternative. However, method has limitations because highly conserved nature makes it challenging to achieve species-level resolution. This study assesses capability two internal transcribed spacers, ITS1 ITS2, along with 28S gene, enhance taxonomic resolution beyond that offered by in free-living host-associated ciliates. Results We compared sequences ITSI, genes downloaded from public databases found ITS2 are more divergent at both inter- intra-specific levels than gene. designed universal primers specific ITS regions for rumen then systematically evaluated these using - silico analysis, PCR assays, metataxonomic or metabarcoding them primers. new inclusive, inclusiveness rate over 80% based on confirmed their specificity evaluation. validated metagenomic DNA freshwater samples samples. Our demonstrated could reveal greater ciliate diversity environments. In particular, detected highest number species, including species genera were not Conclusions regions, particularly ITS1, offer superior resolution, NCBI RefSeq database allows be classified. Therefore, a lesser extent recommended enhancing communities

Language: Английский

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