Adele Statzell-Tallman

Biodiversity and systematics of basidiomycetous yeasts as determined by large-subunit rDNA D1/D2 domain sequence analysis

The molecular systematics of 337 strains of basidiomycetous yeasts and yeast-like fungi, representing 230 species in 18 anamorphic and 24 teleomorphic genera, was determined by sequence analysis of the D1/D2 region of the large-subunit rDNA. The data were compared with published sequences of other basidiomycetous fungi. The results demonstrated that the yeast species and genera are phylogenetically distributed among the Microbotryum, Sporidiobolus, Agaricostilbum and Erythrobasidium clades of the Urediniomycetes; the Tremellales, Trichosporonales ord. nov., Filobasidiales and Cystofilobasidiales clades of the Hymenomycetes; and the Ustilaginales, Microstromatales and Malasseziales clades of the Ustilaginomycetes. Genera such as Bensingtonia, Cryptococcus, Rhodotorula and Sporobolomyces are polyphyletic, i.e. they occur in two or more clades. In contrast, other genera, e.g. Bullera, Cystofilobasidium, Fellomyces, Filobasidiella, Filobasidium, Kondoa, Kurtzmanomyces, Leucosporidium, Rhodosporidium, Sporidiobolus and Udeniomyces, are monophyletic. The majority of the species can be identified using D1/D2 analyses, although the internal transcribed spacer region is required to distinguish closely related species. The intergenic spacer region is recommended for additional differentiation of species and strains.

Candida spencermartinsiae sp. nov., Candida taylorii sp. nov. and Pseudozyma abaconensis sp. nov., novel yeasts from mangrove and coral reef ecosystems

Three species of yeasts are taxonomically described for strains isolated from marine environments. Candida spencermartinsiae sp. nov. (type strain CBS 10894T =NRRL Y-48663T) and Candida taylorii sp. nov. (type strain CBS 8508T =NRRL Y-27213T) are anamorphic ascomycetous yeasts in a phylogenetic cluster of marine yeasts in the Debaryomyces/Lodderomyces clade of the Saccharomycetales. The two species were isolated from multiple locations among coral reefs and mangrove habitats. Pseudozyma abaconensis sp. nov. (type strain CBS 8380T =NRRL Y-17380T) is an anamorphic basidiomycete that is related to the smut fungi of the genus Ustilago in the Ustilaginales. P. abaconensis was collected from waters adjacent to a coral reef.

Validation of the basidiomycetous yeast, Sporidiobolus microsporus sp. nov., based on phenotypic and molecular analyses.

The validation of Sporidiobolus microsporus Higham, nom. nud. is based on phenotypic characterization and molecular sequence analysis of a partial region of the large sub-unit ribosomal DNA. The species is compared, based on phenotypic and molecular characteristics, with other species of Sporidiobolus and the closely related Rhodosporidium fluviale.

Five new species of yeasts from fresh water and marine habitats in the Florida Everglades

Yeast populations in the Shark River Slough of the Florida Everglades, USA, were examined during a 3-year period (2002–2005) at six locations ranging from fresh water marshes to marine mangroves. Seventy-four described species (33 ascomycetes and 41 basidiomycetes) and an approximately equal number of undescribed species were isolated during the course of the investigation. Serious human pathogens, such as Candida tropicalis, were not observed, which indicates that their presence in coastal waters is due to sources of pollution. Some of the observed species were widespread throughout the fresh water and marine habitats, whereas others appeared to be habitat restricted. Species occurrence ranged from prevalent to rare. Five representative unknown species were selected for formal description. The five species comprise two ascomycetes: Candida sharkiensis sp. nov. (CBS 11368T) and Candida rhizophoriensis sp. nov. (CBS 11402T) (Saccharomycetales, Metschnikowiaceae), and three basidiomycetes: Rhodotorulacladiensis sp. nov. (CBS 10878T) in the Sakaguchia clade (Cystobasidiomycetes), Rhodotorula evergladiensis sp. nov. (CBS 10880T) in the Rhodosporidium toruloides clade (Microbotryomycetes, Sporidiobolales) and Cryptococcus mangaliensis sp. nov. (CBS 10870T) in the Bulleromyces clade (Agaricomycotina, Tremellales).

Systematic placement of the basidiomycetous yeastCystofilobasidium lari-marini comb. nov. as predicted by rRNA nucleotide sequence analysis

Based on similarities in basidial morphology and nucleotide sequences of the V3 variable region in the large sub-unit ribosomal RNA, the yeastLeucosporidium lari-marini is considered phylogenetically related to the genusCystofilobasidium. Therefore the new combinationCystofilobasidium lari-marini is proposed.

Blastobotrys von Klopotek (1967)

Publisher Summary This chapter studies the genus Blastobotrys. In the asexual reproduction colonies are restricted, dry, dull, snow-white, cream, or tannish and consist of appressed hyphal growth. Budding cells are absent or present. Conidiophores are suberect, sympodial, and produce conidia in clusters on a rachis or alongside hyphae. Conidia are born on pedicels or denticles or are sessile. Primary conidia produce smaller, secondary conidia, either synchronously or sympodially in short, acropetal chains; primary conidia often bear setae. Septa have micropores. In sexual reproduction it is found that Trichomonascus represents the teleomorphic state of Blastobotrys. The chapter also discusses physiology/biochemistry and phylogenetic placement of the genus in which sugars are often fermented, nitrate is assimilated by some species, coenzyme Q-9 is produced, and the diazonium blue B reaction is negative. The type species taken is Blastobotrys nivea. The genus Blastobotrys, which may bud sparingly or not at all, was originally treated as a hyphomycete, and it was believed to be closely related to the genus Sporothrix from which it was distinguished on morphological criteria. However, members of Blastobotrys, as well as some Sporothrix species, were found to contain mannose as the predominant cell carbohydrate, whereas rhamnose and xylose were absent.

Kwoniella Statzell-Tallman & Fell (2007)

Publisher Summary This chapter discusses the genus Kwoniella. It provides a systematic discussion of the species and concludes with comments on the genus. The diagnosis of the genus is done on the basis of asexual, sexual, physiology and biochemistry, and phylogenetic placement. In asexual reproduction cells are ovoid, ellipsoid to globose, and occur singly or in short chains with one to two multilateral buds. Pseudohyphae and true hyphae are rarely formed. Colonies are white to tan. Ballistoconidia are absent. In sexual reproduction the fungus is dimorphic, with a yeast state and dikaryotic hyphae with clamp connections that develop following conjugation of compatible pairs of strains. Basidia form laterally on branches and apically on the hyphae. Basidia vary in shape from globose to subglobose and lageniform to ovoid with transverse and longitudinal to oblique septa. Navicular basidia have one to three transverse septa. The globose basidia occur singly, in pairs, or in chains. Basidiospores are globose, ovoid to cylindrical, and passively released. Ballistospores are not present. Diagnosis on the basis of physiology and biochemistry reveals that fermentation is absent. A brownish pigment is produced that diffuses into solid media. Diazonium blue B and urease reactions are positive.