Monophyly of Genera and Species of Characeae based on rbcL Sequences, with Special Reference to Australian and European Lychnothamnus barbatus (Characeae: Charophyceae)

1999 ◽  
Vol 47 (3) ◽  
pp. 361 ◽  
Author(s):  
Richard M. McCourt ◽  
Michelle T. Casanova ◽  
Kenneth G. Karol ◽  
Monique Feist
Keyword(s):  
Maximum Likelihood ◽  
Special Reference ◽  
Green Algae ◽  
Large Subunit ◽  
Australian Population ◽  
Sexual Systems ◽  
Limited Variation ◽  
Multiple Species ◽  
Paraphyletic Assemblage ◽  
Rbcl Sequences

Sequences for the chloroplast-encoded large subunit of the Rubisco gene (rbcL) were used to test the monophyly of multiple isolates within species, and multiple species within genera, of green algae in the Characeae (Class Charophyceae). Parsimony and maximum likelihood analyses supported the monophyly of genera and most species, with the exception of a paraphyletic assemblage comprising isolates of two ‘species’, dioecious Chara connivens Salzm. ex A.Br. and monoecious C. globularis Thuill., which together constitute a monophyletic group. The rbcL data support the independent evolution of either monoecious or dioecious sexual systems in the two connivens-globularis, clades. Comparisons of disjunct isolates of the monotypic Lychnothamnus barbatus (Meyen) Leohn. revealed nearly identical rbcL sequences in isolates from Croatia, Germany and Australia, although all three sequences were unique. The variation exhibited by these isolates was similar to variation between isolates within species of Chara and Lamprothamnium from different continents. The limited variation may be due to dispersal of thalli or oospores between continents; however, the rarity of known intercontinental transfers of Characeae in the last two centuries suggests that the Australian population is probably not an exotic from Europe. Lychnothamnus barbatus populations in Australia and elsewhere thus merit continued protected status.

PHOTOSYNTHESIS IN ALGAE: II. GREEN ALGAE WITH SPECIAL REFERENCE TO DUNALIELLA SPP. AND TETRASELMIS SPP.

1966 ◽  
Vol 44 (10) ◽  
pp. 1247-1254 ◽  
Author(s):  
J. S. Craigie ◽  
J. McLachlan ◽  
W. Majak ◽  
R. G. Ackman ◽  
C. S. Tocher
Keyword(s):  
Hydrogen Sulfide ◽  
Special Reference ◽  
Green Algae ◽  
Photosynthetic Rates ◽  
High Level

The photosynthetic fixation of14CO2was studied in 10 species of chlorophycean algae and in 9 isolates of prasinophycean algae of the genus Tetraselmis.Green seaweeds had photosynthetic rates of 2.2 to 4.4 mg CO2 × h−1 × g−1, accumulated starch, glucose, fructose, and sucrose, and excreted very little recent photosynthate.Dunaliella spp. were distinguished by a high level of organic excretion (to 29.2% of the14C fixed in 2 hours), the production of glycerol and hydrogen sulfide, and the absence of dimethyl-β-propiothetin.Tetraselmis spp. excreted relatively small amounts of photosynthate in 2 hours, and produced mannitol and dimethyl-β-propiothetin but not hydrogen sulfide.

scholarly journals Universal target-enrichment baits for anthozoan (Cnidaria) phylogenomics: New approaches to long-standing problems

2017 ◽  
Author(s):  
A.M. Quattrini ◽  
B.C. Faircloth ◽  
L.F. Dueñas ◽  
T.C.L. Bridge ◽  
M. Brugler ◽  
...  
Keyword(s):  
Maximum Likelihood ◽  
Illumina Sequencing ◽  
Phylogenetic Relationships ◽  
Evolutionary Relationships ◽  
Diverse Group ◽  
Target Enrichment ◽  
Library Preparation ◽  
Deep Waters ◽  
The Mean ◽  
Multiple Species

AbstractAnthozoans (e.g., corals, anemones) are an ecologically important and diverse group of marine metazoans that occur from shallow to deep waters worldwide. However, our understanding of the evolutionary relationships among the ∼7500 species within this class is hindered by the lack of phylogenetically informative markers that can be reliably sequenced across a diversity of taxa. We designed and tested 16,308 RNA baits to capture 720 Ultraconserved Element loci and 1,071 exon loci. Library preparation and target enrichment was performed on 33 taxa from all orders within the class Anthozoa. Following Illumina sequencing and Trinity assembly, we recovered 1,774 of 1,791 targeted loci. The mean number of loci recovered from each species was 638 ± 222, with more loci recovered from octocorals (783 ± 138 loci) than hexacorals (475 ±187 loci). Phylogenetically informative sites ranged from 26-49% for alignments at differing hierarchical taxonomic levels (e.g., Anthozoa, Octocorallia, Hexacorallia). The percent of variable sites within each of three genera (Acropora, Alcyonium, andSinularia) for which multiple species were sequenced ranged from 4.7-30%. Maximum likelihood analyses recovered highly resolved trees with topologies matching those supported by other studies, including the monophyly of the order Scleractinia. Our results demonstrate the utility of this target-enrichment approach to resolve phylogenetic relationships from relatively old to recent divergences. Re-designing the baits with improved affinities to capture loci within each sub-class will provide a valuable toolset to address systematic questions and further our understanding of the timing of diversifications in the class Anthozoa.

scholarly journals The Phylogenetic Relationship Revealed Three New Wood-Inhabiting Fungal Species From Genus Trechispora

2021 ◽  
Vol 12 ◽  
Author(s):  
Wei Zhao ◽  
Chang-Lin Zhao
Keyword(s):  
Bayesian Inference ◽  
Maximum Likelihood ◽  
Maximum Parsimony ◽  
Internal Transcribed Spacer ◽  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Fungal Species ◽  
Molecular Evidence ◽  
Wood Degradation ◽  
Inference Methods

Wood-inhabiting fungi play a significant role in wood degradation and the cycle of matter in the ecological system. In the present study, three new wood-inhabiting fungal species, Trechispora bambusicola, Trechispora fimbriata, and Trechispora fissurata spp. nov., are nested in Trechispora, which are proposed based on a combination of morphological features and molecular evidence. Sequences of internal transcribed spacer (ITS) and large subunit (nLSU) regions of the studied samples were generated, and the phylogenetic analyses were performed with maximum likelihood, maximum parsimony, and Bayesian inference methods. The phylogenetic analyses inferred from ITS showed that T. bambusicola was sister to Trechispora stevensonii, T. fimbriata grouped with Trechispora nivea, and T. fissurata grouped with Trechispora echinospora. The phylogenetic tree based on ITS + nLSU sequences demonstrated that T. bambusicola formed a single lineage and then grouped with Trechispora rigida and T. stevensonii. T. fimbriata was sister to T. nivea. T. fissurata grouped with Trechispora thelephora.

Three new species of Russulaceae from India based on morphology and molecular phylogeny

Phytotaxa ◽  
2016 ◽  
Vol 246 (1) ◽  
pp. 61 ◽  
Author(s):  
K. P. Deepna Latha ◽  
K. N. Anil Raj ◽  
V. Adnaan Farook ◽  
Shahina A. Sharafudheen ◽  
Neeraja K. Parambil ◽  
...  
Keyword(s):  
New Species ◽  
Maximum Likelihood ◽  
Molecular Phylogeny ◽  
Internal Transcribed Spacer ◽  
Novel Species ◽  
Large Subunit ◽  
Line Drawings ◽  
Three New Species ◽  
Kerala State ◽  
Blastn Search

Three new species of Russulaceae, Lactifluus umbonatus and Lactifluus indicus belonging to Lf. subg. Gerardii and Lactarius keralensis belonging to L. subg. Piperites, are described from Kerala State, India. Comprehensive descriptions, photographs, line drawings and comparisons with phenetically similar and phylogenetically related species are given. Nuclear ribosomal internal transcribed spacer regions (ITS) of the three species were sequenced and analyzed. In addition, nuclear ribosomal large subunit (nLSU) gene of Lactifluus indicus was sequenced and the sequence was used in BLASTn search to find similar sequences. Maximum likelihood (ML) analysis based on the ITS sequences confirmed both the novelty of these species and their placement within their respective genera. The discovery of Lactifluus umbonatus and Lf. indicus represent the first report of novel species belonging to Lf. subg. Gerardii from India. Lactifluus indicus represents the second record of a pleurotoid Lactifluus species from India.

scholarly journals Phylogeny of Opisthokonta and the evolution of multicellularity and complexity in Fungi and Metazoa

2003 ◽  
Vol 2 (3) ◽  
pp. 203-211 ◽  
Author(s):  
Mónica Medina ◽  
Allen G. Collins ◽  
John W. Taylor ◽  
James W. Valentine ◽  
Jere H. Lipps ◽  
...  
Keyword(s):  
Ribosomal Dna ◽  
Special Interest ◽  
Sequence Data ◽  
Large Subunit ◽  
Sister Group ◽  
Ssu Rdna ◽  
Lsu Rdna ◽  
Evolutionary Transitions ◽  
Stephanoeca Diplocostata ◽  
Paraphyletic Assemblage

While early eukaryotic life must have been unicellular, multicellular lifeforms evolved multiple times from protistan ancestors in diverse eukaryotic lineages. The origins of multicellularity are of special interest because they require evolutionary transitions towards increased levels of complexity. We have generated new sequence data from the nuclear large subunit ribosomal DNA gene (LSU rDNA) and the SSU rDNA gene of several unicellular opisthokont protists – a nucleariid amoeba (Nuclearia simplex) and four choanoflagellates (Codosiga gracilis, Choanoeca perplexa, Proterospongia choanojuncta and Stephanoeca diplocostata) to provide the basis for re-examining relationships among several unicellular lineages and their multicellular relatives (animals and fungi). Our data indicate that: (1) choanoflagellates are a monophyletic rather than a paraphyletic assemblage that independently gave rise to animals and fungi as suggested by some authors and (2) the nucleariid filose amoebae are the likely sister group to Fungi. We also review published information regarding the origin of multicellularity in the opisthokonts.

THE CALCULATION OF THE DOSE-RESPONSE LINE IN QUANTAL ASSAYS WITH SPECIAL REFERENCE TO OESTROGEN ASSAYS BY THE ALLEN-DOISY TECHNIQUE

1952 ◽  
Vol 8 (2) ◽  
pp. 169-178 ◽  
Author(s):  
J. D. BIGGERS
Keyword(s):  
Maximum Likelihood ◽  
Special Reference ◽  
Effective Dose ◽  
Dose Response ◽  
Drug Action ◽  
Weighting Factor ◽  
Relative Potency ◽  
Method Of Maximum Likelihood ◽  
Response Line ◽  
Angular Transformation

A comparison has been made of the probit, logit, angular and rectangular transformations in the calculations of quantal dose response lines by the method of maximum likelihood. Data from Allen-Doisy oestrogen assays have been employed. Studies of the χ2 test for linearity and of the calculated median effective dose (m.e.d.) show no significant differences between the results obtained with any of the transformations. When group numbers are equal the angular transformation is the method of choice as the constant weighting factor reduces the amount of computation involved. The significance of these results, both in the calculation of the m.e.d. or relative potency and to the theory of drug action, has been discussed.

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