scholarly journals Molecular phylogeny and ultrastructure of the lichen microalga Asterochloris mediterranea sp. nov. from Mediterranean and Canary Islands ecosystems

2015 ◽  
Vol 65 (Pt_6) ◽  
pp. 1838-1854 ◽  
Author(s):  
Patricia Moya ◽  
Pavel Škaloud ◽  
Salvador Chiva ◽  
Francisco J. García-Breijo ◽  
José Reig-Armiñana ◽  
...  
Keyword(s):  
Molecular Markers ◽  
Phylogenetic Analyses ◽  
Culture Collection ◽  
Its Rdna ◽  
Lsu Rdna ◽  
Correct Identification ◽  
Holotype Specimen ◽  
Transmission Electron ◽  
Chloroplast Morphology ◽  
Microscopy Techniques

The microalgae of the genus Asterochloris are the preferential phycobionts in Cladonia, Lepraria and Stereocaulon lichens. Recent studies have highlighted the hidden diversity of the genus, even though phycobionts hosting species of the genus Cladonia in Mediterranean and Canarian ecosystems have been poorly explored. Phylogenetic analyses were made by concatenation of the sequences obtained with a plastid – LSU rDNA – and two nuclear – internal transcribed spacer (ITS) rDNA and actin – molecular markers of the phycobionts living in several populations of the Cladonia convoluta-Cladonia foliacea complex, Cladonia rangiformis and Cladonia cervicornis s. str. widely distributed in these areas in a great variety of substrata and habitats. A new strongly supported clade was obtained in relation to the previously published Asterochloris phylogenies. Minimum genetic variation was detected between our haplotypes and other sequences available in the GenBank database. The correct identification of the fungal partners was corroborated by the ITS rDNA barcode. In this study we provide a detailed characterization comprising chloroplast morphology, and ultrastructural and phylogenetic analyses of a novel phycobiont species, here described as Asterochloris mediterranea sp. nov. Barreno, Chiva, Moya et Škaloud. A cryopreserved holotype specimen has been deposited in the Culture Collection of Algae of Charles University in Prague, Czech Republic (CAUP) as CAUP H 1015. We suggest the use of a combination of several nuclear and plastid molecular markers, as well as ultrastructural (transmission electron and confocal microscopy) techniques, both in culture and in the symbiotic state, to improve novel species delimitation of phycobionts in lichens.

Strelitziana sarbhoyi sp. nov. (Strelitzianaceae, Chaetothyriales), from North-Western Himalayas, India, described based on morphology and molecular phylogeny

Phytotaxa ◽  
2019 ◽  
Vol 427 (1) ◽  
pp. 51-59
Author(s):  
SHIWALI RANA ◽  
SANJAY KUMAR SINGH ◽  
PARAS NATH SINGH
Keyword(s):  
Phylogenetic Tree ◽  
Dna Sequences ◽  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Culture Collection ◽  
Fungal Culture ◽  
Western Himalayas ◽  
Holotype Specimen ◽  
North Western

Strelitziana sarbhoyi is established as a new species to accommodate a phylloplane fungus isolated from Mallotus philippensis collected from Kangra region of North-Western Himalayas, Himachal Pradesh. The identity of the fungus is confirmed based on the asexual-morphs, cultural characteristics and phylogenetic analyses of the internal transcribed spacer (ITS) rDNA and partial nuclear ribosomal 28S large subunit (LSU) sequence data. The placement of S. sarbhoyi in the phylogenetic tree was determined based on DNA sequences from authenticated isolates of Strelitziana. Strelitziana sarbhoyi shows nearly 94% similarity with other known species of Strelitziana. Area description is provided for the proposed taxon along with microscopic images, and a phylogenetic tree. This is probably the first report of Strelitziana from India. Holotype specimen (dried voucher culture) is deposited in the Ajrekar Mycological Herbarium (AMH), and an ex-type culture is deposited in National Fungal Culture Collection of India (NFCCI).

Vulcanochloris (Trebouxiales, Trebouxiophyceae), a new genus of lichen photobiont from La Palma, Canary Islands, Spain

Phytotaxa ◽  
2015 ◽  
Vol 219 (2) ◽  
pp. 118 ◽  
Author(s):  
Lucie Vančurová ◽  
Ondřej Peksa ◽  
Yvonne Němcová ◽  
Pavel Škaloud
Keyword(s):  
Geographical Distribution ◽  
Canary Islands ◽  
18S Rdna ◽  
New Genus ◽  
Phylogenetic Analyses ◽  
Its Rdna ◽  
Sister Relationship ◽  
La Palma ◽  
Chloroplast Morphology ◽  
Rbcl Sequences

This paper describes a new genus of lichen photobionts, Vulcanochloris, with three newly proposed species, V. canariensis, V. guanchorum and V. symbiotica. These algae have been discovered as photobionts of lichen Stereocaulon vesuvianum growing on slopes of volcanos and lava fields on La Palma, Canary Islands, Spain. Particular species, as well as the newly proposed genus, are delimited based on ITS rDNA, 18S rDNA and rbcL sequences, chloroplast morphology, and ultrastructural features. Phylogenetic analyses infer the genus Vulcanochloris as a member of Trebouxiophycean order Trebouxiales, in a sister relationship with the genus Asterochloris. Our data point to the similar lifestyle and morphology of these two genera; however, Vulcanochloris can be well distinguished by a unique formation of spherical incisions within the pyrenoid. Mycobiont specificity and geographical distribution of the newly proposed genus is further discussed.

Nanoscale Structural and Chemical Segregation in Pt50Ru50 Electrocatalysts

2001 ◽  
Vol 7 (S2) ◽  
pp. 1112-1113
Author(s):  
Rhonda M. Stroud ◽  
Jeffrey W. Long ◽  
Karen E. Swider-Lyons ◽  
Debra R. Rolison
Keyword(s):  
Methanol Oxidation ◽  
Structural Heterogeneity ◽  
Oxidation Activity ◽  
Bimetallic Alloy ◽  
Transmission Electron ◽  
Chemical Segregation ◽  
High Fraction ◽  
Argon Mixture ◽  
Microscopy Techniques ◽  
Electron Energy Loss

To address how the chemical and structural heterogeneity of Pt50Ru50 nanoparticles affects methanol oxidation activity, we have employed an arsenal of transmission electron microscopy techniques (conventional bright field-imaging, selected area diffraction, atomic-resolution lattice imaging, electron-energy loss spectroscopy, and energy-dispersive x-ray spectroscopy) to characterize 2.5-nm particles in differing oxidation and hydration states. Our studies demonstrate that electrocatalysts containing a high fraction of Ru-rich hydrous oxide, as apposed to the anhydrous PtRu bimetallic alloy, have as much as 250x higher methanol oxidation activityThe nominally 2.5-nm Pt50Ru50 particles were studied in as-received, reduced and reoxidized forms. The reducing treatment consisted of 2 h at 100 °C in flowing 10% PL/argon mixture. For re-oxidation, the reduced particles were heated for 20 h at 100 °C in an H2O-saturated oxygen atmosphere. The particles were suspended in methanol, and pipetted onto holey-carboncoated Cu grids for TEM studies.

scholarly journals Respiratory syncytial virus B sequence analysis reveals a novel early genotype

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Juan C. Muñoz-Escalante ◽  
Andreu Comas-García ◽  
Sofía Bernal-Silva ◽  
Daniel E. Noyola
Keyword(s):  
Molecular Markers ◽  
Respiratory Syncytial Virus ◽  
Maximum Likelihood ◽  
Respiratory Infections ◽  
Phylogenetic Analyses ◽  
Detection Methods ◽  
Sequence Alignments ◽  
Multiple Sequence ◽  
Individual Gene ◽  
Syncytial Virus

AbstractRespiratory syncytial virus (RSV) is a major cause of respiratory infections and is classified in two main groups, RSV-A and RSV-B, with multiple genotypes within each of them. For RSV-B, more than 30 genotypes have been described, without consensus on their definition. The lack of genotype assignation criteria has a direct impact on viral evolution understanding, development of viral detection methods as well as vaccines design. Here we analyzed the totality of complete RSV-B G gene ectodomain sequences published in GenBank until September 2018 (n = 2190) including 478 complete genome sequences using maximum likelihood and Bayesian phylogenetic analyses, as well as intergenotypic and intragenotypic distance matrices, in order to generate a systematic genotype assignation. Individual RSV-B genes were also assessed using maximum likelihood phylogenetic analyses and multiple sequence alignments were used to identify molecular markers associated to specific genotypes. Analyses of the complete G gene ectodomain region, sequences clustering patterns, and the presence of molecular markers of each individual gene indicate that the 37 previously described genotypes can be classified into fifteen distinct genotypes: BA, BA-C, BA-CC, CB1-THB, GB1-GB4, GB6, JAB1-NZB2, SAB1, SAB2, SAB4, URU2 and a novel early circulating genotype characterized in the present study and designated GB0.

scholarly journals Molecular and phylogenetic analysis reveals new diversity of Dunaliella salina from hypersaline environments

2021 ◽  
pp. 1-11
Author(s):  
Andrea Highfield ◽  
Angela Ward ◽  
Richard Pipe ◽  
Declan C. Schroeder
Keyword(s):  
Genetic Diversity ◽  
Phylogenetic Analysis ◽  
Dunaliella Salina ◽  
Phylogenetic Analyses ◽  
Ssu Rdna ◽  
Lsu Rdna ◽  
Hypersaline Environments ◽  
Rdna Its ◽  
Β Carotene ◽  
Selection Of

Abstract Twelve hyper-β carotene-producing strains of algae assigned to the genus Dunaliella salina have been isolated from various hypersaline environments in Israel, South Africa, Namibia and Spain. Intron-sizing of the SSU rDNA and phylogenetic analysis of these isolates were undertaken using four commonly employed markers for genotyping, LSU rDNA, ITS, rbcL and tufA and their application to the study of Dunaliella evaluated. Novel isolates have been identified and phylogenetic analyses have shown the need for clarification on the taxonomy of Dunaliella salina. We propose the division of D. salina into four sub-clades as defined by a robust phylogeny based on the concatenation of four genes. This study further demonstrates the considerable genetic diversity within D. salina and the potential of genetic analyses for aiding in the selection of prospective economically important strains.

Actin type I introns offer potential for increasing phylogenetic resolution in Asterochloris (Chlorophyta: Trebouxiophyceae)

2006 ◽  
Vol 38 (5) ◽  
pp. 435-440 ◽  
Author(s):  
Matthew P. NELSEN ◽  
Andrea GARGAS
Keyword(s):  
Population Genetics ◽  
Phylogenetic Analyses ◽  
Species Concepts ◽  
Its Rdna ◽  
Type I ◽  
Phylogenetic Resolution

Primers are presented to amplify an intron-containing portion of the actin type I locus from Asterochloris algae. The amount of variation and phylogenetic resolution provided by the ITS rDNA are compared with that from the actin locus. The number of variable and parsimony-informative sites within the actin locus was drastically higher than that of the ITS. Phylogenetic analyses of the ITS resulted in poorly resolved trees with low support values. In contrast, phylogenetic analyses of the actin locus yielded trees with better support and resolution. It is concluded that the actin type I introns will be useful for studies investigating species concepts and population genetics.

Orientation domains in the intermediate product Na3TiOF5during the synthesis of anatase TiO2nanosheets with exposed reactive {001} facets

2013 ◽  
Vol 46 (6) ◽  
pp. 1741-1748 ◽  
Author(s):  
Yi Xiong ◽  
Shuangfeng Jia ◽  
Jianbo Wang ◽  
Shang Peng ◽  
Lu Lu ◽  
...  
Keyword(s):  
Intermediate Product ◽  
Cubic Phase ◽  
Monoclinic Structure ◽  
Theory Analysis ◽  
Selected Area Electron Diffraction ◽  
Transmission Electron ◽  
Domain Boundaries ◽  
Coherent Domain ◽  
Microscopy Techniques ◽  
Orientation Domain

A powder of oxyfluorotitanate Na3TiOF5crystals is acquired as an intermediate product during the synthesis of anatase titanium dioxide (TiO2) nanosheets with a large percentage of exposed reactive {001} facets. By application of transmission electron microscopy techniques, mainly energy dispersive spectroscopy and selected-area electron diffraction, coherent domain variants of Na3TiOF5are shown to possess monoclinic structure with space groupP21/n. The occurrence of these orientation domain variants is attributed to the reduction of crystal symmetry as a result of the phase transition from the high-temperature cubic phase to the low-temperature monoclinic phase. Through a detailed group theory analysis, the orientation domains are shown to exhibit 12 variants and 11 domain boundaries, which can be categorized into three types of perpendicular twins and two types of antiparallel twins. This work may provide meaningful insight for understanding the growth mechanism of anatase TiO2with a high percentage of reactive facets.

scholarly journals Ultrastructure of the adrenal gland of paca (Cuniculus paca, Linnaeus, 1766) in captivity

2021 ◽  
Vol 15 (3) ◽  
pp. 203-208
Author(s):  
Sérgio Pinter Garcia Filho ◽  
Leandro Luis Martins ◽  
Paulo Fernandes Marcusso ◽  
Tais Harumi de Castro Sasahara ◽  
Márcia Rita Fernandes Machado
Keyword(s):  
Electron Microscopy ◽  
Adrenal Gland ◽  
Adrenal Glands ◽  
Comparative Anatomy ◽  
The Body ◽  
Cortical Region ◽  
Lateral Incision ◽  
Transmission Electron ◽  
In Captivity ◽  
Microscopy Techniques

Lowland paca (Cuniculus paca, Linnaeus, 1766) is a medium-sized rodent that belongs to the Brazilian fauna. Yet little information on its morphology is found in the specialized literature. Thus, the objective of the work was to study the morphology of the adrenal gland of paca by means of microscopic ultrastructure analysis. The adrenal gland secretes specialized substances in the body which promote biological functions of great importance and will provide valuable information to studies in comparative anatomy. Two (2) adult lowland pacas were used, male and female. Soon after death, the animals were positioned in the supine position; their abdominal cavities were opened by pre-retro umbilical and lateral incision followed by folding of the abdominal walls to expose the glands. The adrenal glands were removed; fragments were collected, fixed and prepared for ultrastructure observations using scanning electron microscopy and transmission electron microscopy techniques. It was observed that the adrenal glands of the paca have divisions as well as the limits of the cortical and medullary region, as well as the subdivisions of the glomerulosa, fasciculated and reticulated areas of the cortical region as in other rodents. An ultrastructure of cells and their components also showed a lot of similarity to that already demonstrated in different rodents.

scholarly journals Fenestelloid clades of the Cucurbitariaceae

2020 ◽  
Vol 44 (1) ◽  
pp. 1-40
Author(s):  
W.M. Jaklitsch ◽  
H. Voglmayr
Keyword(s):  
New Species ◽  
Phylogenetic Analyses ◽  
Fungal Species ◽  
Lsu Rdna ◽  
Phylogenetic Structure ◽  
Protein Coding ◽  
Molecular Phylogenetic ◽  
Type Studies ◽  
Asexual Morphs ◽  
One New Species

Fresh collections and their ascospore and conidial isolates backed up by type studies and molecular phylogenetic analyses of a multigene matrix of partial nuSSU-, complete ITS, partial LSU rDNA, rpb2, tef1 and tub2 sequences were used to evaluate the boundaries and species composition of Fenestella and related genera of the Cucurbitariaceae. Eight species, of which five are new, are recognised in Fenestella s.str., 13 in Parafenestella with eight new species and two in the new genus Synfenestella with one new species. Cucurbitaria crataegi is combined in Fenestella, C. sorbi in Synfenestella, Fenestella faberi and Thyridium salicis in Parafenestella. Cucurbitaria subcaespitosa is distinct from C. sorbi and combined in Neocucurbitaria. Fenestella minor is a synonym of Valsa tetratrupha, which is combined in Parafenestella. Cucurbitaria marchica is synonymous with Parafenestella salicis, Fenestella bavarica with S. sorbi, F. macrospora with F. media, and P. mackenziei is synonymous with P. faberi, and the latter is lectotypified. Cucurbitaria sorbi, C. subcaespitosa and Fenestella macrospora are lecto- and epitypified, Cucurbitaria crataegi, Fenestella media, F. minor and Valsa tetratrupha are epitypified in order to stabilise the names in their phylogenetic positions. A neotype is proposed for Thyridium salicis. A determinative key to species is given. Asexual morphs of fenestelloid fungi are phoma-like and do not differ from those of other representatives of the Cucurbitariaceae. The phylogenetic structure of the fenestelloid clades is complex and can only be resolved at the species level by protein-coding genes, such as rpb2, tef1 and tub2. All fungal species studied here occur, as far as has been possible to determine, on members of Diaporthales, most frequently on asexual and sexual morphs of Cytospora.

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