scholarly journals 18S and ITS2 rDNA sequence-structure phylogeny of Prototheca (Chlorophyta, Trebouxiophyceae)

Biologia ◽  
2021 ◽  
Author(s):  
Tanja Plieger ◽  
Matthias Wolf
Keyword(s):  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Sequence Structure ◽  
Cutaneous Lesions ◽  
Structure Information ◽  
Green Algal ◽  
Mitochondrial Cytochrome B ◽  
Maximum Likelihood Methods ◽  
Immunosuppressed Patients ◽  
Tree Estimation

AbstractProtothecosis is an infectious disease caused by organisms currently classified within the green algal genus Prototheca. The disease can manifest as cutaneous lesions, olecranon bursitis or disseminated or systemic infections in both immunocompetent and immunosuppressed patients. Concerning diagnostics, taxonomic validity is important. Prototheca, closely related to the Chlorella species complex, is known to be polyphyletic, branching with Auxenochlorella and Helicosporidium. The phylogeny of Prototheca was discussed and revisited several times in the last decade; new species have been described. Phylogenetic analyses were performed using ribosomal DNA (rDNA) and partial mitochondrial cytochrome b (cytb) sequence data. In this work we use Internal Transcribed Spacer 2 (ITS2) as well as 18S rDNA data. However, for the first time, we reconstruct phylogenetic relationships of Prototheca using primary sequence and RNA secondary structure information simultaneously, a concept shown to increase robustness and accuracy of phylogenetic tree estimation. Using encoded sequence-structure data, Neighbor-Joining, Maximum-Parsimony and Maximum-Likelihood methods yielded well-supported trees in agreement with other trees calculated on rDNA; but differ in several aspects from trees using cytb as a phylogenetic marker. ITS2 secondary structures of Prototheca sequences are in agreement with the well-known common core structure of eukaryotes but show unusual differences in their helix lengths. An elongation of the fourth helix of some species seems to have occurred independently in the course of evolution.

scholarly journals A new species of Gonyosoma Wagler, 1828 (Serpentes, Colubridae), previously confused with G. prasinum (Blyth, 1854)

2021 ◽  
Vol 5 (1) ◽  
pp. 129-139
Author(s):  
Shuo Liu ◽  
Mian Hou ◽  
Ye Htet Lwin ◽  
Qiaoyan Wang ◽  
Dingqi Rao
Keyword(s):  
New Species ◽  
Bayesian Inference ◽  
Cytochrome B ◽  
Yunnan Province ◽  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Pairwise Distance ◽  
Mitochondrial Cytochrome ◽  
Mitochondrial Cytochrome B ◽  
A New Species

A new species of the genus Gonyosoma Wagler is described from Yunnan Province, China. The new species closely resembles G. prasinum (Blyth), but it is differentiated from the latter species by the following characters: precloacal plate divided, iris blue and inside of mouth greyish-white in life. Based on phylogenetic analyses of mitochondrial cytochrome b sequence data, the new species is recovered as the sister species to G. prasinum by Bayesian Inference and Maximum Likelihood analyses. The uncorrected pairwise distance between the new species and other species of the genus Gonyosoma ranged from 11.78% to 17.07% calculated using the mitochondrial cytochrome b sequence. This discovery increases the number of Gonyosoma species to seven.

Characterization and phylogenomics of the complete mitochondrial genome of the polyzoic cestode Gangesia oligonchis (Platyhelminthes: Onchoproteocephalidea)

2019 ◽  
Vol 94 ◽  
Author(s):  
W.X. Li ◽  
D. Zhang ◽  
P.P. Fu ◽  
R. Song ◽  
H. Zou ◽  
...  
Keyword(s):  
Mitochondrial Genome ◽  
Recombinant Dna ◽  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Complete Mitochondrial Genome ◽  
Rrna Genes ◽  
Gene Arrangement ◽  
Protein Coding ◽  
Maximum Likelihood Methods ◽  
Phylogenetic Resolution

Abstract The order Onchoproteocephalidea (Eucestoda) was recently erected to accommodate the hook-bearing tetraphyllideans and the proteocephalideans, which are characterized by internal proglottization and a tetra-acetabulate scolex. The recognized subfamilies in the Proteocephalidae appeared to be non-monophyletic based on 28S recombinant DNA (rDNA) sequence data. Other molecular markers with higher phylogenetic resolution, such as large mitochondrial DNA fragments and multiple genes, are obviously needed. Thus the mitochondrial genome of Gangesia oligonchis, belonging to the putative earliest diverging group of the Proteocephalidae, was sequenced. The circular mitogenome of G. oligonchis was 13,958 bp in size, and contained the standard 36 genes: 22 transfer RNA genes, two rRNA genes and 12 protein-coding genes, as well as two major non-coding regions. A short NCR and a large NCR (lNCR) region were 216 bp and 419 bp in size, respectively. Highly repetitive regions in the lNCR region were detected with that of 11 repeat units. The mitogenome of G. oligonchis shared 71.1% nucleotide identity with Testudotaenia sp. WL-2016. Phylogenetic analyses of the complete mitochondrial genomes with Bayesian inference and maximum likelihood methods indicated that G. oligonchis formed a sister clade with Testudotaenia sp. WL-2016 with maximum support. The ordinal topology is (Caryophyllidea, (Diphyllobothriidea, (Bothriocephalidea, (Onchoproteocephalidea, Cyclophyllidea)))). The mitogenomic gene arrangement of G. oligonchis was identical to that of Testudotaenia sp. WL-2016. Both mitogenomic and nuclear sequence data for many more taxa are required to effectively explore the inter-relationships among the Onchoproteocephalidea.

Diversification of the North American Doellingeria-Eucephalus Clade (Astereae: Asteraceae) Inferred from Molecular and Morphological Evidence

2019 ◽  
Vol 44 (4) ◽  
pp. 930-942
Author(s):  
Geraldine A. Allen ◽  
Luc Brouillet ◽  
John C. Semple ◽  
Heidi J. Guest ◽  
Robert Underhill
Keyword(s):  
North American ◽  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Sister Group ◽  
Morphological Evidence ◽  
South American ◽  
New Combinations ◽  
The North ◽  
Hybridization Event ◽  
Ancient Hybridization

Abstract—Doellingeria and Eucephalus form the earliest-diverging clade of the North American Astereae lineage. Phylogenetic analyses of both nuclear and plastid sequence data show that the Doellingeria-Eucephalus clade consists of two main subclades that differ from current circumscriptions of the two genera. Doellingeria is the sister group to E. elegans, and the Doellingeria + E. elegans subclade in turn is sister to the subclade containing all remaining species of Eucephalus. In the plastid phylogeny, the two subclades are deeply divergent, a pattern that is consistent with an ancient hybridization event involving ancestral species of the Doellingeria-Eucephalus clade and an ancestral taxon of a related North American or South American group. Divergence of the two Doellingeria-Eucephalus subclades may have occurred in association with northward migration from South American ancestors. We combine these two genera under the older of the two names, Doellingeria, and propose 12 new combinations (10 species and two varieties) for all species of Eucephalus.

scholarly journals Taxonomic Re-Examination of Nine Rosellinia Types (Ascomycota, Xylariales) Stored in the Saccardo Mycological Collection

2021 ◽  
Vol 9 (3) ◽  
pp. 666
Author(s):  
Niccolò Forin ◽  
Alfredo Vizzini ◽  
Federico Fainelli ◽  
Enrico Ercole ◽  
Barbara Baldan
Keyword(s):  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Illumina Miseq ◽  
Botanical Garden ◽  
Molecular Study ◽  
Its2 Sequence ◽  
Type Specimens ◽  
Its1 Sequence ◽  
Dna Sequence Data ◽  
Nomen Novum

In a recent monograph on the genus Rosellinia, type specimens worldwide were revised and re-classified using a morphological approach. Among them, some came from Pier Andrea Saccardo’s fungarium stored in the Herbarium of the Padova Botanical Garden. In this work, we taxonomically re-examine via a morphological and molecular approach nine different Roselliniasensu Saccardo types. ITS1 and/or ITS2 sequences were successfully obtained applying Illumina MiSeq technology and phylogenetic analyses were carried out in order to elucidate their current taxonomic position. Only the ITS1 sequence was recovered for Rosellinia areolata, while for R. geophila, only the ITS2 sequence was recovered. We proposed here new combinations for Rosellinia chordicola, R. geophila and R. horridula, while for R. ambigua, R. areolata, R. australis, R. romana and R. somala, we did not suggest taxonomic changes compared to the current ones. The name Rosellinia subsimilis Sacc. is invalid, as it is a later homonym of R. subsimilis P. Karst. & Starbäck. Therefore, we introduced Coniochaeta dakotensis as a nomen novum for R. subsimilis Sacc. This is the first time that these types have been subjected to a molecular study. Our results demonstrate that old types are an important source of DNA sequence data for taxonomic re-examinations.

scholarly journals Discovery of a new mammal species (Soricidae: Eulipotyphla) from Narcondam volcanic island, India

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Manokaran Kamalakannan ◽  
Chandrakasan Sivaperuman ◽  
Shantanu Kundu ◽  
Govindarasu Gokulakrishnan ◽  
Chinnadurai Venkatraman ◽  
...  
Keyword(s):  
New Species ◽  
Phylogenetic Analyses ◽  
Genetic Distances ◽  
Medium Size ◽  
Mitochondrial Cytochrome ◽  
Volcanic Island ◽  
Mammal Species ◽  
Molecular Approaches ◽  
Mitochondrial Cytochrome B ◽  
Mitochondrial Cytochrome B Gene

AbstractWe discovered a new Crocidura species of shrew (Soricidae: Eulipotyphla) from Narcondam Island, India by using both morphological and molecular approaches. The new species, Crocidura narcondamica sp. nov. is of medium size (head and body lengths) and has a distinct external morphology (darker grey dense fur with a thick, darker tail) and craniodental characters (braincase is rounded and elevated with weak lambdoidal ridges) in comparison to other close congeners. This is the first discovery of a shrew from this volcanic island and increases the total number of Crocidura species catalogued in the Indian checklist of mammals to 12. The newly discovered species shows substantial genetic distances (12.02% to 16.61%) to other Crocidura species known from the Indian mainland, the Andaman and Nicobar Archipelago, Myanmar, and from Sumatra. Both Maximum-Likelihood and Bayesian phylogenetic inferences, based on mitochondrial (cytochrome b) gene sequences showed distinct clustering of all included soricid species and exhibit congruence with the previous evolutionary hypothesis on this mammalian group. The present phylogenetic analyses also furnished the evolutionary placement of the newly discovered species within the genus Crocidura.

Phylogeographic structure and gene flow of Himalayan snowcock (Tetraogallus himalayensis)

2010 ◽  
Vol 60 (4) ◽  
pp. 449-465
Author(s):  
Wen Longying ◽  
Zhang Lixun ◽  
An Bei ◽  
Luo Huaxing ◽  
Liu Naifa ◽  
...  
Keyword(s):  
Demographic History ◽  
Phylogenetic Analyses ◽  
Divergence Time ◽  
Population Expansion ◽  
Population History ◽  
Tibet Plateau ◽  
Phylogeographic Structure ◽  
Mitochondrial Cytochrome B ◽  
History Of ◽  
Qinghai Tibet Plateau

AbstractWe have used phylogeographic methods to investigate the genetic structure and population history of the endangered Himalayan snowcock (Tetraogallus himalayensis) in northwestern China. The mitochondrial cytochrome b gene was sequenced of 102 individuals sampled throughout the distribution range. In total, we found 26 different haplotypes defined by 28 polymorphic sites. Phylogenetic analyses indicated that the samples were divided into two major haplogroups corresponding to one western and one eastern clade. The divergence time between these major clades was estimated to be approximately one million years. An analysis of molecular variance showed that 40% of the total genetic variability was found within local populations, 12% among populations within regional groups and 48% among groups. An analysis of the demographic history of the populations suggested that major expansions have occurred in the Himalayan snowcock populations and these correlate mainly with the first and the second largest glaciations during the Pleistocene. In addition, the data indicate that there was a population expansion of the Tianshan population during the uplift of the Qinghai-Tibet Plateau, approximately 2 million years ago.

scholarly journals Reconsideration of the ‘well-known’ hypotrichous ciliate Pleurotricha curdsi (Shi et al., 2002) Gupta et al., 2003 (Ciliophora, Sporadotrichida), with notes on its morphology, morphogenesis and molecular phylogeny

2015 ◽  
Vol 65 (Pt_9) ◽  
pp. 3216-3225 ◽  
Author(s):  
Xiaoteng Lu ◽  
Chen Shao ◽  
Yuhe Yu ◽  
Alan Warren ◽  
Jie Huang
Keyword(s):  
Sequence Data ◽  
Southern China ◽  
Phylogenetic Analyses ◽  
Large Body ◽  
Small Subunit ◽  
Variable Number ◽  
Ssu Rdna ◽  
Intermediate Form ◽  
Rdna Sequence Data

The oxytrichid species Pleurotricha curdsi (Shi et al., 2002) Gupta et al., 2003, isolated from a tributary of the Yangtze River in the Mudong district of Chongqing, southern China, was reinvestigated with emphasis on its morphology, morphogenesis and small-subunit (SSU) rDNA-based phylogeny. Compared with three previously described populations, the Mudong population of P. curdsi is characterized by its large body size, 170–295 × 65–110 μm in vivo, and by having a variable number of right marginal rows, either two or three. Likewise, the number of right marginal rows anlagen (RMA) is also variable, i.e. usually two, but sometimes several small extra anlagen that give rise to the formation of the third row, are present to the left of the RMAs. We posit that the Mudong population is an intermediate form between the three previously described populations. Phylogenetic analyses based on the SSU rDNA sequence data show that all populations of P. curdsi cluster with the type species of the genus, Pleurotricha lanceolata, in a clade nested within the Oxytrichidae.

scholarly journals Biological and Phylogenetic Analyses Suggest that Two Cryphonectria spp. Cause Cankers of Eucalyptus in Africa

Plant Disease ◽  
2003 ◽  
Vol 87 (11) ◽  
pp. 1329-1332 ◽  
Author(s):  
J. Roux ◽  
H. Myburg ◽  
B. D. Wingfield ◽  
M. J. Wingfield
Keyword(s):  
South Africa ◽  
South America ◽  
South African ◽  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Eucalyptus Grandis ◽  
Its Region ◽  
South African Isolate ◽  
Dna Sequence Data ◽  
The Republic

Cryphonectria cubensis is an economically important pathogen of commercial Eucalyptus spp. Differences have been reported for disease symptoms associated with Cryphonectria canker in South Africa and other parts of the world, and recent DNA-based comparisons have confirmed that the fungus in South Africa is different from that in South America and Australasia. During a disease survey in the Republic of Congo, Cryphonectria canker was identified as an important disease on Eucalyptus grandis and E. urophylla. In this study, we compared Congolese and South African isolates of C. cubensis using DNA sequence data and pathogenicity under greenhouse conditions. The β-tubulin and internal transcribed spacer (ITS) region sequences show that C. cubensis in Congo is different from the fungus in South Africa and that Congolese isolates group most closely with South American isolates. Furthermore, pathogenicity tests showed that a South African isolate was more aggressive than two Congolese isolates. We conclude that two distinct Cryphonectria spp. occur in Africa and hypothesize that the fungus in the Congo probably was introduced into Africa from South America. Both fungi are important pathogens causing disease and death of economically important plantation trees. However, they apparently have different origins and must be treated separately in terms of disease management and quarantine considerations.

Contrasting the population genetic structure of two velvet worm taxa (Onychophora : Peripatopsidae : Peripatopsis) in forest fragments along the south-eastern Cape, South Africa

2017 ◽  
Vol 31 (6) ◽  
pp. 781 ◽  
Author(s):  
Savel R. Daniels ◽  
Megan Dreyer ◽  
Prashant P. Sharma
Keyword(s):  
South Africa ◽  
Population Genetic ◽  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Forest Fragments ◽  
Eastern Cape ◽  
Dna Sequence Data ◽  
Mtdna Coi ◽  
Haplotype Networks ◽  
Velvet Worm

During the present study, we examined the phylogeography and systematics of two species of velvet worm (Peripatopsis Pocock, 1894) in the forested region of the southern Cape of South Africa. A total of 89 P. moseleyi (Wood-Mason, 1879) and 65 P. sedgwicki (Purcell, 1899) specimens were collected and sequenced for the cytochrome c oxidase subunit I mtDNA (COI). In addition, a single P. sedgwicki specimen per sample locality was sequenced for the 18S rRNA locus. Furthermore, morphological variation among P. sedgwicki sample localities were explored using traditional alpha taxonomic characters. DNA sequence data were subjected to phylogenetic analyses using Bayesian inference and population genetic analyses using haplotype networks and analyses of molecular variance (AMOVAs). Phylogenetic results revealed the presence of four and three clades within P. moseleyi and P. sedgwicki respectively. Haplotype networks were characterised by the absence of shared haplotypes between clades, suggesting genetic isolation, a result corroborated by the AMOVA and highly significant FST values. Specimens from Fort Fordyce Nature Reserve were both genetically and morphologically distinct from the two remaining P. sedgwicki clades. The latter result suggests the presence of a novel lineage nested within P. sedgwicki and suggests that species boundaries within this taxon require re-examination.

Elusive Relationships Within Order Fabales: Phylogenetic Analyses Using matK and rbcL Sequence Data

2009 ◽  
Vol 34 (1) ◽  
pp. 102-114 ◽  
Author(s):  
M. A. Bello ◽  
A. Bruneau ◽  
F. Forest ◽  
J. A. Hawkins
Keyword(s):  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Morphological Evidence ◽  
Taxon Sampling ◽  
Rapid Radiation ◽  
Bayesian Approaches ◽  
Molecular Studies ◽  
Alternative Hypotheses ◽  
The One ◽  
Good Support

The order Fabales, including Leguminosae, Polygalaceae, Quillajaceae and Surianaceae, represents a novel hypothesis emerging from angiosperm molecular phylogenies. Despite good support for the order, molecular studies to date have suggested contradictory, poorly supported interfamilial relationships. Our reappraisal of relationships within Fabales addresses past taxon sampling deficiencies, and employs parsimony and Bayesian approaches using sequences from the plastid regions rbcL (166 spp.) and matK (78 spp.). Five alternative hypotheses for interfamilial relationships within Fabales were recovered. The Shimodaira-Hasegawa test found the likelihood of a resolved topology significantly higher than the one calculated for a polytomy, but did not favour any of the alternative hypotheses of relationship within Fabales. In the light of the morphological evidence available and the comparative behavior of rbcL and matK, the topology recovering Polygalaceae as sister to the rest of the order Fabales with Leguminosae more closely related to Quillajaceae + Surianaceae, is considered the most likely hypothesis of interfamilial relationships of the order. Dating of selected crown clades in the Fabales phylogeny using penalized likelihood suggests rapid radiation of the Leguminosae, Polygalaceae, and (Quillajaceae + Surianaceae) crown clades.

Sign in / Sign up

Export Citation Format

Share Document