Novel Evolutionary Lineages Revealed in the Chaetothyriales (Fungi) Based on Multigene Phylogenetic Analyses and Comparison of ITS Secondary Structure
نویسندگان
چکیده
Cyphellophora and Phialophora (Chaetothyriales, Pezizomycota) comprise species known from skin infections of humans and animals and from a variety of environmental sources. These fungi were studied based on the comparison of cultural and morphological features and phylogenetic analyses of five nuclear loci, i.e., internal transcribed spacer rDNA operon (ITS), large and small subunit nuclear ribosomal DNA (nuc28S rDNA, nuc18S rDNA), β-tubulin, DNA replication licensing factor (mcm7) and second largest subunit of RNA polymerase II (rpb2). Phylogenetic results were supported by comparative analysis of ITS1 and ITS2 secondary structure of representatives of the Chaetothyriales and the identification of substitutions among the taxa analyzed. Base pairs with non-conserved, co-evolving nucleotides that maintain base pairing in the RNA transcript and unique evolutionary motifs in the ITS2 that characterize whole clades or individual taxa were mapped on predicted secondary structure models. Morphological characteristics, structural data and phylogenetic analyses of three datasets, i.e., ITS, ITS-β-tubulin and 28S-18S-rpb2-mcm7, define a robust clade containing eight species of Cyphellophora (including the type) and six species of Phialophora. These taxa are now accommodated in the Cyphellophoraceae, a novel evolutionary lineage within the Chaetothyriales. Cyphellophora is emended and expanded to encompass species with both septate and nonseptate conidia formed on discrete, intercalary, terminal or lateral phialides. Six new combinations in Cyphellophora are proposed and a dichotomous key to species accepted in the genus is provided. Cyphellophora eugeniae and C. hylomeconis, which grouped in the Chaetothyriaceae, represent another novel lineage and are introduced as the type species of separate genera.
منابع مشابه
Comparative Phylogenetic Perspectives on the Evolutionary Relationships in the Brine Shrimp Artemia Leach, 1819 (Crustacea: Anostraca) Based on Secondary Structure of ITS1 Gene
This is the first study on phylogenetic relationships in the genus Artemia Leach, 1819 using the pattern and sequence of secondary structures of internal transcribed spacer 1 (ITS1). Significant intraspecific variation in the secondary structure of ITS1 rRNA was found in Artemia tibetiana. In the phylogenetic tree based on joined primary and secondary structure sequences, Artemia urmiana and pa...
متن کاملPhylogenetic Analysis of Beta-Glucanase Producing Actinomycetes Strain TBG-CH22 - A Comparison of Conventional and Molecular Morphometric Approach
Actinomycetes are inexhaustible producers of commercially valuable metabolites, are continually screened for beneficial compounds. The taxonomic and phylogenetic study of novel actinomycetes strains are mostly based on conventional methods and primary DNA structure of 16s rRNA. Although 16s rRNA sequence is well accepted in phylogeny studies, its secondary structures have not been widely used. ...
متن کاملPhylogenetic Analysis of Beta-Glucanase Producing Actinomycetes Strain TBG-CH22 - A Comparison of Conventional and Molecular Morphometric Approach
Actinomycetes are inexhaustible producers of commercially valuable metabolites, are continually screened for beneficial compounds. The taxonomic and phylogenetic study of novel actinomycetes strains are mostly based on conventional methods and primary DNA structure of 16s rRNA. Although 16s rRNA sequence is well accepted in phylogeny studies, its secondary structures have not been widely used. ...
متن کاملA rock-inhabiting ancestor for mutualistic and pathogen-rich fungal lineages
Rock surfaces are unique terrestrial habitats in which rapid changes in the intensity of radiation, temperature, water supply and nutrient availability challenge the survival of microbes. A specialised, but diverse group of free-living, melanised fungi are amongst the persistent settlers of bare rocks. Multigene phylogenetic analyses were used to study relationships of ascomycetes from a variet...
متن کاملPunctuationlism and Gradualistic Evolutionary Trends of Eight Phylogenetic Lineages of Maastrichtian to Eocene and Recent Benthic Foraminifera from the Tethys
Minor differences in the morphology of the test, wall structure, arrangement of chambers and apertures, size are recognized as being of decisive specific or subspecific value. Twenty four phylogenetic lineages were produced by puncuated equilibrium and gradualistic evolutionary trends which observed within 50 benthic foraminiferal species and subspecies belonging to 18 genera throughout the Maa...
متن کامل