scholarly journals Mitochondrial Genomes of Two Thaparocleidus Species (Platyhelminthes: Monogenea) Reveal the First rRNA Gene Rearrangement among the Neodermata

2019 ◽  
Vol 20 (17) ◽  
pp. 4214 ◽  
Author(s):  
Dong Zhang ◽  
Hong Zou ◽  
Ivan Jakovlić ◽  
Shan G. Wu ◽  
Ming Li ◽  
...  
Keyword(s):  
Gene Order ◽  
Phylogenetic Analyses ◽  
Sister Group ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Order Analysis ◽  
Coding Regions ◽  
High Gene ◽  
Phylogenetic Framework ◽  
Gene Order Rearrangement

Phylogenetic framework for the closely related Ancylodiscoidinae and Ancyrocephalinae subfamilies remains contentious. As this issue was never studied using a large molecular marker, we sequenced the first two Ancylodiscoidinae mitogenomes: Thaparocleidus asoti and Thaparocleidus varicus. Both mitogenomes had two non-coding regions (NCRs) that contained a number of repetitive hairpin-forming elements (RHE). Due to these, the mitogenome of T. asoti (16,074 bp) is the longest among the Monogenea; especially large is its major NCR, with 3500 bp, approximately 1500 bp of which could not be sequenced (thus, the total mitogenome size is ≈ 17,600 bp). Although RHEs have been identified in other monopisthocotyleans, they appear to be independently derived in different taxa. The presence of RHEs may have contributed to the high gene order rearrangement rate observed in the two mitogenomes, including the first report of a transposition of rRNA genes within the Neodermata. Phylogenetic analyses using mitogenomic dataset produced Dactylogyrinae embedded within the Ancyrocephalinae (paraphyly), whereas Ancylodiscoidinae formed a sister-group with them. This was also supported by the gene order analysis. 28S rDNA dataset produced polyphyletic Dactylogyridae and Ancyrocephalinae. The phylogeny of the two subfamilies shall have to be further evaluated with more data.

scholarly journals Phylogeny and Synonymy of Gyrodinium heterostriatum comb. nov. (Dinophyceae), a Common Unarmored Dinoflagellate in the World Oceans [plus supplementary materials]

2020 ◽  
Vol 59 (2) ◽  
pp. 77-87
Author(s):  
Fernando Gómez ◽  
Luis F. Artigas ◽  
Rebecca J. Gast
Keyword(s):  
North Sea ◽  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Morphological Plasticity ◽  
Sister Group ◽  
Rrna Gene ◽  
Microbial World ◽  
The North ◽  
The North Sea ◽  
Environmental Sequences

The North Sea and the English Channel are regions with a long tradition of plankton studies, where the colony-forming haptophyte Phaeocystis globosa dominates the spring phytoplankton blooms. Among its predators, we investigated an abundant unarmored dinoflagellate (~3000 cells per liter) in the North Sea in May 2019. It has been reported in the literature as Gymnodinium heterostriatum or G. striatissimum, and often identified as Gyrodinium spirale. Phylogenetic analyses using the small-, large subunit- and Internal Transcriber Spacers of the ribosomal RNA (SSU-, LSU-, ITS rRNA) gene sequences indicate that our isolates clustered within the Gyrodinium clade. The new sequences formed a sister group with sequences of the freshwater taxon Gyrodinium helveticum, being one of the infrequent marine-freshwater transitions in the microbial world. This isolate is the first characterized member of a clade of numerous environmental sequences widely distributed from cold to tropical seas. This common and abundant taxon has received several names due to its morphological plasticity (changes of size and shape, often deformed after engulfing prey) and the difficulty in discerning surface striation. We conclude that the priority is for the species name Gymnodinium heterostriatum Kofoid & Swezy 1921, a new name that was proposed for Gymnodinium spirale var. obtusum sensu Dogiel 1906. The species Gyrodinium striatissimum (Hulburt 1957) Gert Hansen & Moestrup 2000 and Gymnodinium lucidum D. Ballantine in Parke & Dixon 1964 (=G. hyalinum M. Lebour 1925) are posterior synonyms. We propose Gyrodinium heterostriatum comb. nov. for Gymnodinium heterostriatum.

scholarly journals Vitellibacter echinoideorum sp. nov., isolated from a sea urchin (Tripneustes gratilla)

2015 ◽  
Vol 65 (Pt_7) ◽  
pp. 2320-2325 ◽  
Author(s):  
Shih-Yao Lin ◽  
Asif Hameed ◽  
Cheng-Zhe Wen ◽  
You-Cheng Liu ◽  
Yi-Han Hsu ◽  
...  
Keyword(s):  
16S Rrna ◽  
Sea Urchins ◽  
Sequence Similarity ◽  
Phylogenetic Analyses ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Rrna Gene ◽  
The Novel ◽  
Moderate Amount ◽  
Polar Lipid Profile

A Gram-stain-negative, aerobic, rod-shaped, yellow-pigment-producing bacterium (designated strain CC-CZW007T) was isolated from seafood samples (sea urchins) at Penghu Island in Taiwan. Strain CC-CZW007T grew optimally at pH 7.0 and 30 °C in the presence of 3 % (w/v) NaCl. The novel strain shared highest 16S rRNA gene sequence similarity to Vitellibacter vladivostokensis JCM 11732T (96.8 %), Vitellibacter soesokkakensis KCTC 32536T (96.4 %), Vitellibacter nionensis KCTC 32420T (95.8 %) and Vitellibacter aestuarii JCM 15496T (95.6 %) and lower sequence similarity to members of other genera. Phylogenetic analyses based on 16S rRNA genes revealed a distinct taxonomic position attained by strain CC-CZW007T with respect to other species of the genus Vitellibacter. The major fatty acids were iso-C15 : 0 and iso-C17 : 0 3-OH. The polar lipid profile was composed of major amounts of phosphatidylethanolamine, unidentified lipids and aminolipids; a moderate amount of aminophospholipid was also detected. The DNA G+C content was 34.7 mol%. The predominant quinone system was menaquinone (MK-6). On the basis of polyphasic taxonomic evidence presented here, strain CC-CZW007T is proposed to represent a novel species within the genus Vitellibacter, for which the name Vitellibacter echinoideorum sp. nov. is proposed. The type strain is CC-CZW007T ( = BCRC 80886T = JCM 30378T).

A combined morphological and molecular phylogeny for sea urchins (Echinoidea: Echinodermata)

1995 ◽  
Vol 347 (1320) ◽  
pp. 213-234 ◽  
Keyword(s):  
Data Base ◽  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Total Evidence ◽  
Morphological Data ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Molecular Sequences ◽  
Higher Taxa ◽  
Stem Group

Phylogenedc reladonships of higher taxa of echinoids have been invesdgated using a 163 character morphological data base and molecular sequences from large and small subunit (LSU and SSU) ribosomal RNA (rRNA) genes. The complete ssu rRNA gene has been sequenced for 21 taxa, with representatives from nine of the 14 extant orders of Echinoidea. Partial LSU sequences, representing the first 400 base pairs (b.p.) from the 5' end were also sequenced for three taxa to complement an existing data base of ten taxa. The two molecular sequences provided a total of 371 variable sites, of which 143 were phylogenetically informative (compared to 145 phylogenetically informative sites from morphological data). Morphological, LSU and SSU data have been analysed separately and together. Morphological and ssu sequence data generate topologies that are not significantly in conflict (under Templeton’s test), but the strong signal pairing arbaciids with clypeasteroids in the LSU derived tree marks the LSU sequence data as anomalous for this taxon. A ‘ total evidence’ approach derived a tree very similar in topology to that derived from morphological data. Rooted on the stem group echinoid Archaeocidaris , our total evidence tree suggested relationships of higher taxa as follows: Gidaroida Phormosomatidae Echinothuriidae Diadematidae Spatangoida Clypeasteroida, Cassiduloida Calycina, Arbacioida Stomopneustidae Glyphocidaridae Temnopleuridae Echinometridae Echinidae, Strongylocentridae. Phylogenetic analyses run both with and without key fossil taxa yielded slightly different topologies. It is important to include fossil taxa in a phylogenetic analysis where there are long stem-group branches or where the crown group is highly derived.

scholarly journals Description of Eurystomatella sinica n. gen., n. sp., with establishment of a new family Eurystomatellidae n. fam. (Protista, Ciliophora, Scuticociliatia) and analyses of its phylogeny inferred from sequences of the small-subunit rRNA gene

2010 ◽  
Vol 60 (2) ◽  
pp. 460-468 ◽  
Author(s):  
Miao Miao ◽  
Yangang Wang ◽  
Weibo Song ◽  
John C. Clamp ◽  
Khaled A. S. Al-Rasheid
Keyword(s):  
New Genus ◽  
Phylogenetic Analyses ◽  
Sister Group ◽  
Small Subunit ◽  
Rrna Gene ◽  
Small Subunit Rrna ◽  
New Family ◽  
Small Subunit Rrna Gene ◽  
The Family ◽  
Great Divergence

Recently, an undescribed marine ciliate was isolated from China. Investigation of its morphology and infraciliature revealed it as an undescribed species representing a new genus, Eurystomatella n. gen., the type of the new family Eurystomatellidae n. fam. The new family is defined by close-set, apically positioned oral membranelles and a dominant buccal field that is surrounded by an almost completely circular paroral membrane. The new genus is defined by having a small oral membranelle 1 (M1), bipartite M2 and well-developed M3, a body surface faintly sculptured with a silverline system in a quadrangular, reticulate pattern and a cytostome located at the anterior third of a large buccal field. The type species of the new genus, Eurystomatella sinica n. sp., is a morphologically unique form that is defined mainly by the combination of a conspicuously flattened body, several caudal cilia, extremely long cilia associated with the buccal apparatus and a contractile vacuole located subcaudally. According to phylogenetic analyses of small-subunit (SSU) rRNA gene sequences, Eurystomatella clusters with the genus Cyclidium, as a sister group to the family Pleuronematidae. The great divergence in both buccal and somatic ciliature between Eurystomatella and all other known scuticociliates supports the establishment of a new family for Eurystomatella.

scholarly journals Phylogenomic and Comparative Analyses of Complete Plastomes of Croomia and Stemona (Stemonaceae)

2018 ◽  
Vol 19 (8) ◽  
pp. 2383 ◽  
Author(s):  
Qixiang Lu ◽  
Wenqing Ye ◽  
Ruisen Lu ◽  
Wuqin Xu ◽  
Yingxiong Qiu
Keyword(s):  
Gene Order ◽  
Phylogenetic Analyses ◽  
Sequence Divergence ◽  
Early Pleistocene ◽  
Disjunct Distribution ◽  
Rrna Genes ◽  
Trna Genes ◽  
Protein Coding ◽  
Intergenic Spacers ◽  
Protein Coding Genes

The monocot genus Croomia (Stemonaceae) comprises three herbaceous perennial species that exhibit EA (Eastern Asian)–ENA (Eastern North American) disjunct distribution. However, due to the lack of effective genomic resources, its evolutionary history is still weakly resolved. In the present study, we conducted comparative analysis of the complete chloroplast (cp) genomes of three Croomia species and two Stemona species. These five cp genomes proved highly similar in overall size (154,407–155,261 bp), structure, gene order and content. All five cp genomes contained the same 114 unique genes consisting of 80 protein-coding genes, 30 tRNA genes and 4 rRNA genes. Gene content, gene order, AT content and IR/SC boundary structures were almost the same among the five Stemonaceae cp genomes, except that the Stemona cp genome was found to contain an inversion in cemA and petA. The lengths of five genomes varied due to contraction/expansion of the IR/SC borders. A/T mononucleotides were the richest Simple Sequence Repeats (SSRs). A total of 46, 48, 47, 61 and 60 repeats were identified in C. japonica, C. heterosepala, C. pauciflora, S. japonica and S. mairei, respectively. A comparison of pairwise sequence divergence values across all introns and intergenic spacers revealed that the ndhF–rpl32, psbM–trnD and trnS–trnG regions are the fastest-evolving regions. These regions are therefore likely to be the best choices for molecular evolutionary and systematic studies at low taxonomic levels in Stemonaceae. Phylogenetic analyses of the complete cp genomes and 78 protein-coding genes strongly supported the monophyly of Croomia. Two Asian species were identified as sisters that likely diverged in the Early Pleistocene (1.62 Mya, 95% HPD: 1.125–2.251 Mya), whereas the divergence of C. pauciflora dated back to the Late Miocene (4.77 Mya, 95% HPD: 3.626–6.162 Mya). The availability of these cp genomes will provide valuable genetic resources for further population genetics and phylogeographic studies on Croomia.

scholarly journals Phenotypic and molecular characterization of a novel strongly hemolytic Brachyspira species, provisionally designated “Brachyspira hampsonii”

2012 ◽  
Vol 24 (5) ◽  
pp. 903-910 ◽  
Author(s):  
Yogesh Chander ◽  
Alexander Primus ◽  
Simone Oliveira ◽  
Connie J. Gebhart
Keyword(s):  
United States ◽  
Phylogenetic Analyses ◽  
The United States ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Diagnostic Laboratory ◽  
Brachyspira Hyodysenteriae ◽  
Phylogenetic Grouping ◽  
Enzymatic Profiling ◽  
Swine Herds

Since 2007, outbreaks of severe bloody diarrhea and hemorrhagic colitis have been reported in the United States and Canada. Though the primary causative agent of swine dysentery is Brachyspira hyodysenteriae, which is strongly hemolytic, the current report describes the isolation of a novel strongly hemolytic Brachyspira sp. This novel Brachyspira sp. was identified from clinical submissions at the Minnesota Veterinary Diagnostic Laboratory, and 40 of such isolates were obtained from 22 clinical submissions representing 5 states. Isolates were confirmed to be different from any known Brachyspira sp. on the basis of phylogenetic analysis of nucleotide sequences of nox and 16S ribosomal RNA (rRNA) genes. Phylogenetic analyses grouped all isolates into 2 clades (clades I and II), and grouping patterns were similar for both nox and 16S rRNA gene sequence analyses. Phenotypically, all isolates were indole and hippurate negative, and enzymatic profiling indicated 2 types of profiles, irrespective of the phylogenetic grouping, differing only in the production of β-glucosidase. The results suggest that a potentially virulent new species of Brachyspira sp., provisionally named “ Brachyspira hampsonii ”, is circulating among swine herds in the United States.

Redescriptions of three trachelocercid ciliates (Protista, Ciliophora, Karyorelictea), with notes on their phylogeny based on small subunit rRNA gene sequences

2013 ◽  
Vol 63 (Pt_9) ◽  
pp. 3506-3514 ◽  
Author(s):  
Ying Yan ◽  
Yuan Xu ◽  
Zhenzhen Yi ◽  
Alan Warren
Keyword(s):  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Small Subunit ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Ssu Rrna ◽  
Small Subunit Rrna ◽  
Small Subunit Rrna Gene ◽  
Ssu Rrna Gene Sequence ◽  
First Time

Three trachelocercid ciliates, Kovalevaia sulcata (Kovaleva, 1966) Foissner, 1997, Trachelocerca sagitta (Müller, 1786) Ehrenberg, 1840 and Trachelocerca ditis (Wright, 1982) Foissner, 1996, isolated from two coastal habitats at Qingdao, China, were investigated using live observation and silver impregnation methods. Data on their infraciliature and morphology are supplied. The small subunit rRNA (SSU rRNA) genes of K. sulcata and Trachelocerca sagitta were sequenced for the first time. Phylogenetic analyses based on SSU rRNA gene sequence data indicate that both organisms, and the previously sequenced Trachelocerca ditis, are located within the trachelocercid assemblage and that K. sulcata is sister to an unidentified taxon forming a clade that is basal to the core trachelocercids.

scholarly journals The Bacterial Community in the Gut of the Cockroach Shelfordella lateralis Reflects the Close Evolutionary Relatedness of Cockroaches and Termites

2012 ◽  
Vol 78 (8) ◽  
pp. 2758-2767 ◽  
Author(s):  
Christine Schauer ◽  
Claire L. Thompson ◽  
Andreas Brune
Keyword(s):  
Bacterial Community ◽  
Phylogenetic Analyses ◽  
Rflp Analysis ◽  
Sister Group ◽  
Rrna Gene ◽  
Content Type ◽  
Evolutionary Relatedness ◽  
Termite Gut ◽  
Molecular Phylogenetic ◽  
Metabolic Activities

ABSTRACTTermites and cockroaches are closely related, with molecular phylogenetic analyses even placing termites within the radiation of cockroaches. The intestinal tract of wood-feeding termites harbors a remarkably diverse microbial community that is essential for the digestion of lignocellulose. However, surprisingly little is known about the gut microbiota of their closest relatives, the omnivorous cockroaches. Here, we present a combined characterization of physiological parameters, metabolic activities, and bacterial microbiota in the gut ofShelfordella lateralis, a representative of the cockroach family Blattidae, the sister group of termites. We compared the bacterial communities within each gut compartment using terminal-restriction fragment length polymorphism (T-RFLP) analysis and made a 16S rRNA gene clone library of the microbiota in the colon—the dilated part of the hindgut with the highest density and diversity of bacteria. The colonic community was dominated by members of theBacteroidetes,Firmicutes(mainlyClostridia), and someDeltaproteobacteria. SpirochaetesandFibrobacteres, which are abundant members of termite gut communities, were conspicuously absent. Nevertheless, detailed phylogenetic analysis revealed that many of the clones from the cockroach colon clustered with sequences previously obtained from the termite gut, which indicated that the composition of the bacterial community reflects at least in part the phylogeny of the host.

scholarly journals 16S rRNA Phylogenetic Investigation of the Candidate Division “Korarchaeota”

2006 ◽  
Vol 72 (7) ◽  
pp. 5077-5082 ◽  
Author(s):  
Thomas A. Auchtung ◽  
Cristina D. Takacs-Vesbach ◽  
Colleen M. Cavanaugh
Keyword(s):  
16S Rrna ◽  
Hot Springs ◽  
Phylogenetic Analyses ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Environmental Distribution ◽  
Candidate Division ◽  
High Level ◽  
The 16S Rrna Gene

ABSTRACT The environmental distribution and phylogeny of “Korarchaeota,” a proposed ancient archaeal division, was investigated by using the 16S rRNA gene framework. Korarchaeota-specific primers were designed based on previously published sequences and used to screen a variety of environments. Korarchaeota 16S rRNA genes were amplified exclusively from high temperature Yellowstone National Park hot springs and a 9°N East Pacific Rise deep-sea hydrothermal vent. Phylogenetic analyses of these and all available sequences suggest that Korarchaeota exhibit a high level of endemicity.

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