Multigene phylogenetic analysis of the Trichomonascus, Wickerhamiella and Zygoascus yeast clades, and the proposal of Sugiyamaella gen. nov. and 14 new species combinations

Abstract

Relationships among species assigned to the ascosporic yeast genera Sporopachydermia, Stephanoascus, Trichomonascus, Wickerhamiella and Zygoascus, and to the associated anamorphic genera Arxula, Blastobotrys, Sympodiomyces and Trigonopsis, were determined from phylogenetic analyses of gene sequences from the nearly complete large-subunit rRNA gene, the mitochondrial small-subunit rRNA gene, and cytochrome oxidase II. The genus Stephanoascus is polyphyletic, resulting in reassignment of two species to the older genus Trichomonascus and the third to Sugiyamaella gen. nov. (type species Sugiyamaella smithiae). The genera Sporopachydermia, Wickerhamiella and Zygoascus appear to be monophyletic. The species Pichia ofunaensis and P. tannicola are proposed for transfer to Zygoascus. Arxula, Blastobotrys and Sympodiomyces are members of the Trichomonascus clade, with the genus Blastobotrys having taxonomic priority for anamorphic states. Trigonopsis variabilis and three species of Candida represent a distinct clade. From the foregoing gene sequence analyses, the new ascosporic genus Sugiyamaella is proposed, as are 14 new species combinations and the new family Trichomonascaceae.

The yeast genus Tortispora gen. nov., description of Tortispora ganteri sp. nov., Tortispora mauiana f.a., sp. nov., Tortispora agaves f.a., sp. nov., Tortispora sangerardonensis f.a., sp. nov., Tortispora cuajiniquilana f.a., sp. nov., Tortispora starmeri f.a., sp. nov. and Tortispora phaffii f.a., sp. nov., reassignment of Candida caseinolytica to Tortispora caseinolytica f.a., comb. nov., emendation of Botryozyma, and assignment of Botryozyma, Tortispora gen. nov. and Trigonopsis to the family Trigonops

“…The insertion exhibited homology to introns found in various fungal species, with the highest identities to introns found in the large subunit rRNA genes of Lipomyces yamadae (DQ518983) and the ustilaginous species Sporisorium andrewmitchellii (JQ995370). Homology with the intron located at position 2566 in the C. caseinolytica large subunit gene (DQ442710, Kurtzman & Robnett, 2007) was also detected, but the degree of divergence exceeded that seen for the other two species (21 % vs 19 % substitutions, respectively), discounting the possibility of a relatively recent transfer between species of the same clade. We successfully determined sequences of the full ITS-D1/D2 span in 12 strains, a nearly complete sequence for strain UWOPS 84-201.5 (ITS deposited as KC681890) and only the D1/D2 region in strains G91-5062B, G91-618.4 and G91-714.5.…”

Trichomonascus apis sp. nov., a heterothallic yeast species from honeycomb

“…1). The phylogenetic tree exhibits an arrangement of the included species similar to that of the tree derived from the analysis of multigene sequences by Kurtzman & Robnett (2007). The four strains share identical D1/D2 sequences (the GenBank accession number of strain NCAIM Y.01848 T is indicated on the phylogenetic tree depicted in Fig.…”

“…As Trichomonascus H. S. Jackson (1947) has taxonomic priority over Stephanoascus M. Th. Smith, van der Walt & E. Johannsen (1976), S. ciferrii and the related species Stephanoascus farinosus were transferred to the genus Trichomonascus (Kurtzman & Robnett, 2007). Similarly, the same authors transferred most of the anamorphic species of the Trichomonascus clade to the genus Blastobotrys von Klopotek (1967), which has taxonomic priority over Sympodiomyces Fell & Statzel (1971) and Arxula van der Walt, M. Th.…”

“…However, he argued that the nearly identical unique morphology of the sexual states of T. mycophagus and T. petasosporus leaves little doubt that they are closely related. A multigene phylogenetic analysis revealed that T. petasosporus is related closely to Stephanoascus ciferrii, the type species of the genus Stephanoascus (Kurtzman & Robnett, 2007). As Trichomonascus H. S. Jackson (1947) has taxonomic priority over Stephanoascus M. Th.…”

Characterization and expression analysis of a gene cluster for nitrate assimilation from the yeast Arxula adeninivorans

“…Blastobotrys adeninivorans - Kurtzmann and Robnett, 2007) is a haploid (Samsonova et al, 1996), nonpathogenic, thermo- (Wartmann et al, 1995) and halotolerant (Yang et al, 2000;Böer et al, 2004a) dimorphic yeast with unusual biochemical characteristics. Thus, it can grow on a range of compounds as sole energy and carbon source; these include xylose, tannic acid, n-alkanes and purines (Middelhoven et al, 1984(Middelhoven et al, , 1991(Middelhoven et al, , 1992Gienow et al, 1990;van der Walt et al, 1990).…”