Open AccessMolecular Phylogenetics of the Genus Trichosporon Inferred from Mitochondrial Cytochrome b Gene Sequences
Author(s) -
Swarajit Kumar Biswas,
Li Wang,
Koji Yokoyama,
Kazuko Nishimura
Publication year - 2005
Publication title -
journal of clinical microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.349
H-Index - 255
eISSN - 1070-633X
pISSN - 0095-1137
DOI - 10.1128/jcm.43.10.5171-5178.2005
Subject(s) - trichosporon , biology , phylogenetic tree , phylogenetics , genetics , maximum parsimony , microbiology and biotechnology , gene , yeast , clade
Mitochondrial cytochromeb (cytb ) genes of 42 strains representing 23 species of the genusTrichosporon were partially sequenced to determine their molecular phylogenetic relationships. Almost half of the 22 strains investigated (from 11 different species) contained introns in their sequences. Analysis of a 396-bp coding sequence from each strain ofTrichosporon under investigation showed a total of 141 (35.6%) variable nucleotide sites. A phylogenetic tree based on the cytb gene sequences revealed that all species ofTrichosporon exceptTrichosporon domesticum andTrichosporon montevideense had species-specific cytb genes.Trichosporon sp. strain CBS 5581 was identified asTrichosporon pullulans , and one clinical isolate, IFM 48794, was identified asTrichosporon faecale . Analysis of 132-bp deduced amino acid sequences showed a total of 34 (25.75%) variable amino acid sites.T. domesticum andT. montevideense ,Trichosporon asahii andTrichosporon asteroides , andTrichosporon gracile andTrichosporon guehoae had identical amino acid sequences. A phylogenetic tree constructed with the ascomycetesSaccharomyces douglasii andCandida glabrata taken as outgroup species and including representative species from closely related genera species ofTrichosporon clustered with other basidiomycetous yeasts that contain xylose in their cell wall compositions. These results indicate the effectiveness of mitochondrial cytb gene sequences for both species identification and the phylogenetic analysis ofTrichosporon species.