scholarly journals Amphidinium stirisquamtum sp. nov. (Dinophyceae), a new marine sand-dwelling dinoflagellate with a novel type of body scale

ALGAE ◽  
2021 ◽  
Vol 36 (4) ◽  
pp. 241-261
Author(s):  
Zhaohe Luo ◽  
Na Wang ◽  
Hala F. Mohamed ◽  
Ye Liang ◽  
Lulu Pei ◽  
...  
Keyword(s):  
Large Subunit ◽  
Detailed Examination ◽  
Small Subunit ◽  
Sensu Stricto ◽  
Small Subunit Rrna ◽  
Body Scale ◽  
Benthic Dinoflagellates ◽  
Marine Sand ◽  
Molecular Tree ◽  
The Right

Amphidinium species are amongst the most abundant benthic dinoflagellates in marine intertidal sandy ecosystems. Some of them produce a variety of bioactive compounds that have both harmful effects and pharmaceutical potential. In this study, Amphidinium cells were isolated from intertidal sand collected from the East China Sea. The two strains established were subjected to detailed examination by light, and scanning and transmission electron microscopy. The vegetative cells had a minute, irregular, and triangular-shaped epicone deflected to the left, thus fitting the description of Amphidinium sensu stricto. These strains are distinguished from other Amphidinium species by combination characteristics: (1) longitudinal flagellum inserted in the lower third of the cell; (2) icicle-shaped scales, 276 ± 17 nm in length, on the cell body surface; (3) asymmetrical hypocone with the left side longer than the right; and (4) presence of immotile cells. Therefore, they are described here as Amphidinium stirisquamtum sp. nov. The molecular tree inferred from small subunit rRNA, large subunit rRNA, and internal transcribed spacer-5.8S sequences revealed that A. stirisquamtum is grouped together with the type species of Amphidinium, A. operculatum, in a fully supported clade, but is distantly related to other Amphidinium species bearing body scale. Live A. stirisquamtum cells greatly affected the survival of rotifers and brine shrimp, their primary grazers, making them more susceptible to predation by the higher tropic level consumers in the food web. This will increase the risk of introducing toxicity, and consequently, the bioaccumulation of toxins through marine food webs.

scholarly journals The Evolution of Life Modes in Stictidaceae, with Three Novel Taxa

2021 ◽  
Vol 7 (2) ◽  
pp. 105
Author(s):  
Vinodhini Thiyagaraja ◽  
Robert Lücking ◽  
Damien Ertz ◽  
Samantha C. Karunarathna ◽  
Dhanushka N. Wanasinghe ◽  
...  
Keyword(s):  
New Species ◽  
Large Scale ◽  
Sequence Data ◽  
Large Subunit ◽  
Monte Carlo Sampling ◽  
Small Subunit ◽  
Sensu Stricto ◽  
Internal Transcribed Spacers ◽  
Character State ◽  
Phenotypic Data

Ostropales sensu lato is a large group comprising both lichenized and non-lichenized fungi, with several lineages expressing optional lichenization where individuals of the same fungal species exhibit either saprotrophic or lichenized lifestyles depending on the substrate (bark or wood). Greatly variable phenotypic characteristics and large-scale phylogenies have led to frequent changes in the taxonomic circumscription of this order. Ostropales sensu lato is currently split into Graphidales, Gyalectales, Odontotrematales, Ostropales sensu stricto, and Thelenellales. Ostropales sensu stricto is now confined to the family Stictidaceae, which includes a large number of species that are poorly known, since they usually have small fruiting bodies that are rarely collected, and thus, their taxonomy remains partly unresolved. Here, we introduce a new genus Ostropomyces to accommodate a novel lineage related to Ostropa, which is composed of two new species, as well as a new species of Sphaeropezia, S. shangrilaensis. Maximum likelihood and Bayesian inference analyses of mitochondrial small subunit spacers (mtSSU), large subunit nuclear rDNA (LSU), and internal transcribed spacers (ITS) sequence data, together with phenotypic data documented by detailed morphological and anatomical analyses, support the taxonomic affinity of the new taxa in Stictidaceae. Ancestral character state analysis did not resolve the ancestral nutritional status of Stictidaceae with confidence using Bayes traits, but a saprotrophic ancestor was indicated as most likely in a Bayesian binary Markov Chain Monte Carlo sampling (MCMC) approach. Frequent switching in nutritional modes between lineages suggests that lifestyle transition played an important role in the evolution of this family.

scholarly journals Pre-AIDS Era Isolates of Pneumocystis carinii f. sp. hominis: High Genotypic Similarity with Contemporary Isolates

1998 ◽  
Vol 36 (1) ◽  
pp. 90-93 ◽  
Author(s):  
Anthony G. Tsolaki ◽  
Pieter Beckers ◽  
Ann E. Wakefield
Keyword(s):  
Large Subunit ◽  
Pneumocystis Carinii ◽  
Small Subunit ◽  
Its Sequence ◽  
Small Subunit Rrna ◽  
Aids Pandemic ◽  
Genes Encoding ◽  
Lsu Rrna ◽  
Large Subunit Rrna ◽  
Sequence Types

Isolates of Pneumocystis carinii f. sp.hominis were examined from six individuals who died ofP. carinii pneumonia between 1968 and 1981 and who had underlying immunodeficiencies which were not due to human immunodeficiency virus infection. DNA sequence variation was analyzed in the genes encoding the mitochondrial large subunit rRNA (mt LSU rRNA), the internal transcribed spacer (ITS) regions of the nuclear rRNA, the arom locus, and the mitochondrial small subunit rRNA. No major variations were observed when these isolates were compared to isolates from HIV-infected individuals. A small number of minor differences were detected. A new position at which variation occurred in the mt LSU rRNA was observed in one sample. Three new ITS sequence types were identified. A total of nine different ITS sequence types were found in the six samples. Mixed infection with different ITS sequence types of P. carinii f. sp. hominis was observed in four of the six samples. The ITS locus was the most informative of the four loci for distinguishing among the isolates ofP. carinii f. sp. hominis. The data suggest that isolates of P. carinii f. sp. hominis from before the AIDS pandemic are genetically very similar to those currently found in HIV-infected individuals.

scholarly journals Microbial Composition of Near-Boiling Silica-Depositing Thermal Springs throughout Yellowstone National Park

2002 ◽  
Vol 68 (10) ◽  
pp. 5123-5135 ◽  
Author(s):  
Carrine E. Blank ◽  
Sherry L. Cady ◽  
Norman R. Pace
Keyword(s):  
Yellowstone National Park ◽  
National Park ◽  
Hydrogen Oxidation ◽  
Large Subunit ◽  
Microbial Community Composition ◽  
Pcr Amplification ◽  
Small Subunit ◽  
Rrna Genes ◽  
Small Subunit Rrna ◽  
Microbial Composition

ABSTRACT The extent of hyperthermophilic microbial diversity associated with siliceous sinter (geyserite) was characterized in seven near-boiling silica-depositing springs throughout Yellowstone National Park using environmental PCR amplification of small-subunit rRNA genes (SSU rDNA), large-subunit rDNA, and the internal transcribed spacer (ITS). We found that Thermocrinis ruber, a member of the order Aquificales, is ubiquitous, an indication that primary production in these springs is driven by hydrogen oxidation. Several other lineages with no known close relatives were identified that branch among the hyperthermophilic bacteria. Although they all branch deep in the bacterial tree, the precise phylogenetic placement of many of these lineages is unresolved at this time. While some springs contained a fair amount of phylogenetic diversity, others did not. Within the same spring, communities in the subaqueous environment were not appreciably different than those in the splash zone at the edge of the pool, although a greater number of phylotypes was found along the pool's edge. Also, microbial community composition appeared to have little correlation with the type of sinter morphology. The number of cell morphotypes identified by fluorescence in situ hybridization and scanning electron microscopy was greater than the number of phylotypes in SSU clone libraries. Despite little variation in Thermocrinis ruber SSU sequences, abundant variation was found in the hypervariable ITS region. The distribution of ITS sequence types appeared to be correlated with distinct morphotypes of Thermocrinis ruber in different pools. Therefore, species- or subspecies-level divergences are present but not detectable in highly conserved SSU sequences.

Isolation of high-quality total RNA from rumen anaerobic bacteria and fungi, and subsequent detection of glycoside hydrolases

2011 ◽  
Vol 57 (7) ◽  
pp. 590-598 ◽  
Author(s):  
Pan Wang ◽  
Meng Qi ◽  
Perry Barboza ◽  
Mary Beth Leigh ◽  
Emilio Ungerfeld ◽  
...  
Keyword(s):  
Gene Expression ◽  
Solid Phase ◽  
Large Subunit ◽  
Rna Extraction ◽  
Small Subunit ◽  
Glycoside Hydrolases ◽  
Small Subunit Rrna ◽  
High Quality ◽  
Major Barrier ◽  
Total Rna

The rumen is one of the most powerful fibrolytic fermentation systems known. Gene expression analyses, such as reverse transcription PCR (RT-PCR), microarrays, and metatranscriptomics, are techniques that could significantly expand our understanding of this ecosystem. The ability to isolate and stabilize representative RNA samples is critical to obtaining reliable results with these procedures. In this study, we successfully isolated high-quality total RNA from the solid phase of ruminal contents by using an improved RNA extraction method. This method is based on liquid nitrogen grinding of whole ruminal solids without microbial detachment and acid guanidinium – phenol – chloroform extraction combined with column purification. Yields of total RNA were as high as 150 µg per g of fresh ruminal content. The typical large subunit/small subunit rRNA ratio ranged from 1.8 to 2.0 with an RNA integrity number (Agilent Technologies) greater than 8.5. By eliminating the detachment step, the resulting RNA was more representative of the complete ecosystem. Our improved method removed a major barrier limiting analysis of rumen microbial function from a gene expression perspective. The polyA-tailed eukaryotic mRNAs obtained have successfully been applied to next-generation sequencing, and metatranscriptomic analysis of the solid fraction of rumen contents revealed abundant sequences related to rumen fungi.

scholarly journals Three Small Nucleolar RNAs Identified from the Spliced Leader-Associated RNA Locus in Kinetoplastid Protozoans

1998 ◽  
Vol 18 (8) ◽  
pp. 4409-4417 ◽  
Author(s):  
T. Guy Roberts ◽  
Nancy R. Sturm ◽  
Billy K. Yee ◽  
Michael C. Yu ◽  
Toinette Hartshorne ◽  
...  
Keyword(s):  
Large Subunit ◽  
Small Subunit ◽  
Cell Fractionation ◽  
Small Nucleolar Rnas ◽  
Small Subunit Rrna ◽  
Base Pairs ◽  
Spliced Leader ◽  
Repeat Units ◽  
Large Subunit Rrna ◽  
Nucleolar Rnas

ABSTRACT First characterized in Trypanosoma brucei, the spliced leader-associated (SLA) RNA gene locus has now been isolated from the kinetoplastids Leishmania tarentolae and Trypanosoma cruzi. In addition to the T. brucei SLA RNA, bothL. tarentolae and T. cruzi SLA RNA repeat units also yield RNAs of 75 or 76 nucleotides (nt), 92 or 94 nt, and ∼450 or ∼350 nt, respectively, each with significant sequence identity to transcripts previously described from the T. brucei SLA RNA locus. Cell fractionation studies localize the three additional RNAs to the nucleolus; the presence of box C/D-like elements in two of the transcripts suggests that they are members of a class of small nucleolar RNAs (snoRNAs) that guide modification and cleavage of rRNAs. Candidate rRNA-snoRNA interactions can be found for one domain in each of the C/D element-containing RNAs. The putative target site for the 75/76-nt RNA is a highly conserved portion of the small subunit rRNA that contains 2′-O-ribose methylation at a conserved position (Gm1830) in L. tarentolae and in vertebrates. The 92/94-nt RNA has the potential to form base pairs near a conserved methylation site in the large subunit rRNA, which corresponds to position Gm4141 of small rRNA 2 in T. brucei. These data suggest that trypanosomatids do not obey the general 5-bp rule for snoRNA-mediated methylation.

scholarly journals Morphology, morphogenesis and molecular phylogeny of an oxytrichid ciliate, Rubrioxytricha haematoplasma (Blatterer & Foissner, 1990) Berger, 1999 (Ciliophora, Hypotricha)

2015 ◽  
Vol 65 (Pt_1) ◽  
pp. 309-320 ◽  
Author(s):  
Wenping Chen ◽  
Xumiao Chen ◽  
Lifang Li ◽  
Alan Warren ◽  
Xiaofeng Lin
Keyword(s):  
Gene Sequence ◽  
Staining Method ◽  
Sequence Data ◽  
Small Subunit ◽  
Rrna Gene ◽  
Rrna Gene Sequence ◽  
Small Subunit Rrna ◽  
Small Subunit Rrna Gene ◽  
Single Mass ◽  
The Right

The morphology and morphogenesis of an oxytrichid ciliate, Rubrioxytricha haematoplasma (Blatterer & Foissner, 1990) Berger, 1999, collected from brackish and marine waters in China, were investigated using live observation and the protargol staining method. The main features of the morphogenetic process are: (i) the parental adoral zone of membranelles is retained completely in the proter and the anlage of undulating membranes originates from dedifferentiation of the old structures; (ii) three frontal, four frontoventral, one buccal, five ventral and five transverse cirri are derived from the anlagen of the undulating membranes and the five streaks of frontal-ventral-transverse anlagen in the pattern of 1 : 3 : 3 : 3 : 4 : 4 from left to right; (iii) the morphogenesis of the dorsal kineties is simpler than the Oxytricha pattern, i.e. without fragmentation of the dorsal kinety 3 anlagen; (iv) the single caudal cirrus originates from the dorsal kinety 3 anlage on the right side; (v) the two macronuclear nodules fuse into a single mass during the mid-stage of morphogenesis. These features correspond well with Rubrioxytricha indica, indicating that the morphogenetic pattern of Rubrioxytricha is stable. Phylogenetic analysis based on small-subunit rRNA gene sequence data supports the monophyly of the genus Rubrioxytricha, which is nested within the non-Stylonychinae clade.

Schistonchus hirtus n. sp. (Nematoda: Aphelenchoididae), an associate of Ficus hirta in China

Nematology ◽  
2010 ◽  
Vol 12 (4) ◽  
pp. 543-556 ◽  
Author(s):  
Yongsan Zeng ◽  
Weimin Ye ◽  
Robin M. Giblin-Davis ◽  
Changhui Li ◽  
Zhijian Du ◽  
...  
Keyword(s):  
Sequence Data ◽  
Large Subunit ◽  
Morphological Characters ◽  
Small Subunit ◽  
Rrna Gene ◽  
Small Subunit Rrna ◽  
Wasp Species ◽  
Dna Sequence Data ◽  
Ficus Hirta ◽  
Large Subunit Rrna

Abstract A nematode recovered from syconia of Ficus hirta from Guangzhou, P. R. China, during a survey of nematode biodiversity from 2007 to 2009, is described herein as Schistonchus hirtus n. sp. and is differentiated by a combination of morphological characters, including excretory pore (EP) located near the metacorpus, a short post-uterine sac (PUS) (0.5 vulval body diam. (VBD) long), rose thorn-shaped spicules, amoeboid sperm, absence of gubernaculum, three pairs of subventral papillae on the male tail, host-Ficus and host-wasp species and DNA sequence data. Morphologically, S. hirtus n. sp. is close to S. centerae, S. altermacrophylla, S. aureus, S. laevigatus and S. virens based upon the length of the PUS (about 0.5 VBD long). However, the relative position of the EP in S. hirtus n. sp. is very different from these species (near metacorpus vs near head). With regard to the EP character, S. hirtus n. sp. is very similar to S. macrophylla, S. guangzhouensis and S. caprifici where the EP is at metacorpus level. However, S. hirtus n. sp. differs from S. macrophylla and S. guangzhouensis by possessing a shorter PUS and smaller spicules, and differs from S. caprifici by a shorter female stylet and smaller spicules. Schistonchus hirtus n. sp. was easily differentiated from other sequenced species by the proportion of parsimony informative changes in the partial small subunit rRNA gene (SSU) and D2/D3 expansion segments of the large subunit rRNA gene (LSU). Phylogenetic analysis with SSU sequences suggests that S. hirtus n. sp. is in a highly supported monophyletic clade with Aphelenchoides and Laimaphelenchus and is polyphyletic to other sequenced Schistonchus species. With LSU sequence data, it forms a clade with S. caprifici and they appear polyphyletic relative to S. guangzhouensis, S. centerae, S. aureus, S. laevigatus and S. virens.

Characterisation of, and entomopathogenic studies on, Pristionchus aerivorus (Cobb in Merrill & Ford, 1916) Chitwood, 1937 (Rhabditida: Diplogastridae) from North Carolina, USA

Nematology ◽  
2015 ◽  
Vol 17 (5) ◽  
pp. 567-580
Author(s):  
Weimin Ye ◽  
Qing Yu ◽  
Natsumi Kanzaki ◽  
Paul R. Adams ◽  
Yasmin J. Cardoza
Keyword(s):  
North Carolina ◽  
Helicoverpa Zea ◽  
Large Subunit ◽  
Small Subunit ◽  
Morphological Observation ◽  
Rrna Gene ◽  
Small Subunit Rrna ◽  
Morphological Studies ◽  
The Status ◽  
Molecular Phylogenetic

During a survey of entomopathogenic nematodes in North Carolina, USA, aPristionchusspecies was recovered using theGalleriabait method. Morphological studies with light microscopy and scanning electron microscopy, mating tests with reference strains, as well as molecular analyses of the near-full-length small subunit rRNA gene (18S) and D2-D3 expansion segments of the large subunit rRNA gene (28S) identified this isolate asPristionchus aerivorus. ExposedGallerialarvae were killed within 48 h and high numbers of nematodes were recovered from the cadavers about 5 days later. Preliminary tests revealed that this nematode is capable of infecting at least two other insect species (Helicoverpa zeaandTenebrio molitor) under laboratory conditions. The status of the genusChroniodiplogasteris discussed and confirmed as a junior synonym ofPristionchusbased on morphological observation and molecular phylogenetic analysis.

scholarly journals Characterization of a Novel Hypotrich Ciliate From Heavy Metal-Contaminated Industrial Outlet in Onsan, Ulsan, South Korea

2021 ◽  
Vol 12 ◽  
Author(s):  
Santosh Kumar ◽  
Daizy Bharti ◽  
Shahed Uddin Ahmed Shazib ◽  
Mann Kyoon Shin
Keyword(s):  
New Species ◽  
South Korea ◽  
Phylogenetic Analyses ◽  
Small Subunit ◽  
Rrna Gene ◽  
Small Subunit Rrna ◽  
Gene Sequences ◽  
A Cell ◽  
The Right

Very few studies exist on the description of protozoan ciliates from industrially contaminated sites. In this study, we report a description of a novel hypotrich ciliate isolated from water samples collected from an industrially contaminated outlet in Onsan, Ulsan, South Korea. The oxytrichid ciliate, Histriculus tolerans n. sp., was investigated using live observation and protargol impregnation. The morphology, morphogenesis, and molecular phylogeny inferred from small-subunit (SSU) rRNA gene sequences were studied. The new species is mainly characterized by a cell size of about 70 × 40 μm in vivo, two elongate ellipsoidal macronuclear nodules and one or two micronuclei, adoral zone of about 51% of body length with 32 membranelles on average, about 34 cirri in the right and 24 cirri in the left marginal row, 18 frontoventral transverse cirri, six dorsal kineties including two dorsomarginal rows, and dorsal kinety 1 with 26 bristles. Morphogenesis is similar to that of the type species, i.e., Histriculus histrio, except that oral primordium does not contribute to anlage II of the proter. Phylogenetic analyses, based on small-subunit rRNA gene sequences, consistently place the new species within the family Oxytrichidae, clustering with H. histrio.

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