scholarly journals Phylogeny, evidence for a cryptic plastid, and distribution of Chytriodinium parasites (Dinophyceae) infecting copepods

2018 ◽  
Author(s):  
Jürgen F. H. Strassert ◽  
Elisabeth Hehenberger ◽  
Javier del Campo ◽  
Noriko Okamoto ◽  
Martin Kolisko ◽  
...  
Keyword(s):  
Phylogenetic Position ◽  
Rrna Gene ◽  
Ancestral State ◽  
Ssu Rrna ◽  
Gene Sequences ◽  
Free Living ◽  
Surface Ocean ◽  
Lsu Rrna Gene ◽  
Important Host ◽  
Copepod Eggs

ABSTRACTSpores of the dinoflagellate Chytriodinium are known to infest copepod eggs causing their lethality. Despite the potential to control the population of such an ecologically important host, knowledge about Chytriodinium parasites is limited: we know little about phylogeny, parasitism, abundance, or geographical distribution. We carried out genome sequence surveys on four manually isolated sporocytes from the same sporangium to analyse the phylogenetic position of Chytriodinium based on SSU and concatenated SSU/LSU rRNA gene sequences, and also characterize two genes related to the plastidial heme pathway, hemL and hemY. The results suggest the presence of a cryptic plastid in Chytriodinium and a photosynthetic ancestral state of the parasitic Chytriodinium/Dissodinium clade. Finally, by mapping Tara Oceans V9 SSU amplicon data to the recovered SSU rRNA gene sequences from the sporocytes, we show that globally, Chytriodinium parasites are most abundant within the pico/nano- and mesoplankton of the surface ocean and almost absent within microplankton, a distribution indicating that they generally exist either as free-living spores or host-associated sporangia.

scholarly journals Asgard archaea are diverse, ubiquitous, and transcriptionally active microbes

2018 ◽  
Author(s):  
Mingwei Cai ◽  
Yang Liu ◽  
Zhichao Zhou ◽  
Yuchun Yang ◽  
Jie Pan ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
Genomic Analysis ◽  
Phylogenetic Position ◽  
Rrna Gene ◽  
Gene Sequences ◽  
16S Rrna Gene Sequences ◽  
Group D ◽  
Origin Of Eukaryotes

AbstractAsgard is a newly proposed archaeal superphylum. Phylogenetic position of Asgard archaea and its relationships to the origin of eukaryotes is attracting increasingly research interest. However, in-depth knowledge of their diversity, distribution, and activity of Asgard archaea remains limited. Here, we used phylogenetic analysis to cluster the publicly available Asgard archaeal 16S rRNA gene sequences into 13 subgroups, including five previously unknown subgroups. These lineages were widely distributed in anaerobic environments, with the majority of 16S rRNA gene sequences (92%) originating from sediment habitats. Co-occurrence analysis revealed potential relationships between Asgard, Bathyarchaeota, and Marine Benthic Group D archaea. Genomic analysis suggested that Asgard archaea are potentially mixotrophic microbes with divergent metabolic capabilities. Importantly, metatranscriptomics confirmed the versatile lifestyles of Lokiarchaeota and Thorarchaeota, which can fix CO2using the tetrahydromethanopterin Wood-Ljungdahl pathway, perform acetogenesis, and degrade organic matters. Overall, this study broadens the understandings of Asgard archaea ecology, and also provides the first evidence to support a transcriptionally active mixotrophic lifestyle of Asgard archaea, shedding light on the potential roles of these microorganisms in the global biogeochemical cycling.

Ficophagus chaozhouensis n. sp. (Nematoda: Aphelenchoididae), an associate of Ficus hirta Vahl var. roxburghii (Miq.) King in China

Nematology ◽  
2020 ◽  
Vol 22 (3) ◽  
pp. 299-312
Author(s):  
Wensheng Zeng ◽  
Dayuan Zhang ◽  
Jianghua Huang ◽  
Yongsan Zeng ◽  
Weimin Ye ◽  
...  
Keyword(s):  
Large Subunit ◽  
Nematode Species ◽  
Small Subunit ◽  
Rrna Gene ◽  
Ssu Rrna ◽  
Monophyletic Clade ◽  
Male Tail ◽  
Lsu Rrna Gene ◽  
Ficus Hirta ◽  
Tail Tip

Summary A new nematode species was recovered from the syconia of Ficus hirta var. roxburghii from Chaozhou, Guangdong, China. It is described herein as Ficophagus chaozhouensis n. sp. and is characterised by possessing the combined characters of a short post-uterine sac, excretory pore located near the head, amoeboid sperm, three pairs of subventral papillae on the male tail, rounded male tail tip with mucron (occasionally swollen), absence of gubernaculum (or apophysis), a blunt rosethorn-shaped spicule without a terminal cucullus, and a digitate rostrum with a broadly squared tip. Ficophagus chaozhouensis n. sp. was separated from other sequenced species by differences in the partial small subunit (SSU) rRNA gene and D2-D3 expansion segments of the large subunit (LSU) rRNA gene. Phylogenetic analysis with LSU D2-D3 expansion segment sequences suggested that F. chaozhouensis n. sp. is clustered in the same highly supported monophyletic clade with F. aculeata, F. maxima and F. yoponensis, and is sister to F. aculeata.

Molecular and morphological studies on the subantarctic genus Orceolina (Agyriaceae)

2001 ◽  
Vol 33 (4) ◽  
pp. 323-329 ◽  
Author(s):  
R.S. Poulsen ◽  
I. Schmitt ◽  
U. Søchting ◽  
H. T. Lumbsch
Keyword(s):  
Maximum Parsimony ◽  
Nucleotide Sequences ◽  
Rrna Gene ◽  
Gene Sequences ◽  
Morphological Studies ◽  
The Family ◽  
Lsu Rrna Gene ◽  
High Bootstrap ◽  
Lsu Rrna

AbstractThe subantarctic genus Orceolina is revised and two species are accepted, i.e. Orceolina antarctica Mull. Arg. R. S. Poulsen Søchting comb. nov. and Orceolina kerguelensis (Tuck.) Hertel. Descriptions of the species are provided. In addition the phylogeny of the genus Orceolina and allied taxa was investigated using nucleotide sequences of the LSU rRNA gene. Sequences from these regions of nine agyrialean fungi were aligned to those of four representatives of Pertusariales used as outgroup. The alignment was analysed cladistically using maximum parsimony. The two Orceolina clustered together within the Agyriaceae. The placement in the family is supported by high bootstrap values and the Kishino-Hasegawa test.

scholarly journals Kluyveromyces osmophilus is not a synonym of Zygosaccharomyces mellis; reinstatement as Zygosaccharomyces osmophilus comb. nov.

2020 ◽  
Vol 70 (5) ◽  
pp. 3374-3378 ◽  
Author(s):  
Thelma T. S. Matos ◽  
Juliana F. Teixeira ◽  
Laura G. Macías ◽  
Ana Raquel O. Santos ◽  
Sung-Oui Suh ◽  
...  
Keyword(s):  
Type Strain ◽  
Stingless Bees ◽  
Rrna Gene ◽  
Gene Sequences ◽  
Orthologous Genes ◽  
Single Strain ◽  
Lsu Rrna Gene ◽  
Tetragonisca Angustula ◽  
Lsu Rrna ◽  
Phylogenomic Analyses

Kluyveromyces osmophilus, a single-strain species isolated from Mozambique sugar, has been treated a synonym of Zygosaccharomyces mellis. Analyses of D1/D2 LSU rRNA gene sequences confirmed that the species belongs to the genus Zygosaccharomyces but showed it to be distinct from strains of Z. mellis. During studies of yeasts associated with stingless bees in Brazil, nine additional isolates of the species were obtained from unripe and ripe honey and pollen of Scaptotrigona cfr. bipunctata, as well as ripe honey of Tetragonisca angustula. The D1/D2 sequences of the Brazilian isolates were identical to those of the type strain of K. osmophilus CBS 5499 (=ATCC 22027), indicating that they represent the same species. Phylogenomic analyses using 4038 orthologous genes support the reinstatement of K. osmophilus as a member of the genus Zygosaccharomyces. We, therefore, propose the name Zygosaccharomyces osmophilus comb. nov. (lectotype ATCC 22027; MycoBank no. MB 833739).

The smallest known heliozoans are the Erebor lineage (nom. clad. n.) inside Microheliella maris (Eukaryota, Diaphoretickes), with the amendation of M. maris diagnosis and description of Berkeleyaesol magnus gen. nov., comb. nov. (Eukaryota, incertae sedis)

2021 ◽  
Vol 71 (4) ◽  
Author(s):  
Yegor Shishkin ◽  
Daria Drachko ◽  
Vasily V. Zlatogursky
Keyword(s):  
New Genus ◽  
Gene Sequencing ◽  
Sister Group ◽  
Rrna Gene ◽  
Ssu Rrna ◽  
Morphometric Data ◽  
Free Living ◽  
Incertae Sedis ◽  
Rrna Gene Sequencing ◽  
Cell Body Size

A new strain of planktonic heliozoans (ZI172) belonging to the genus Microheliella (the sister group of Cryptista in Diaphoretickes), closely related to the only one known strain of Microheliella maris (CCAP 1945/1), was studied with light microscopy and SSU rRNA gene sequencing. Morphometric data obtained from 127 cells and based on 254 measurements showed that this strain represents the smallest heliozoan (1.66–3.42 µm, av. 2.56 µm) in diameter known to date and one of the smallest free-living eukaryotes. We also did morphometry for strain CCAP 1945/1. Its cell body size is 3.20–6.47 µm (av. 4.15 µm; n=141; m=282). The secondary structures of hairpin 15 of the SSU rRNA molecules were reconstructed for ZI172 and CCAP 1945/1 and they were compared The possible biochemical explanation for the smaller size of the ZI172 strain, which is smaller than the CCAP 1945/1 strain, is discussed, including all published electron micrographs of CCAP 1945/1. The necessary taxonomic work is also carried out. The diagnosis of Microheliella maris is amended and the new infraspecific clade Erebor is described to include ZI172. The measurements and systematics of the enigmatic heliozoan ‘Raphidiophrys’ magna O’Donoghue 1922 (non 1921; the biggest known heliozoan) are also discussed and it is transferred to the new genus Berkeleyaesol.

Sign in / Sign up

Export Citation Format

Share Document