Characterization of two unrecorded yeast species in the families Cystobasidiaceae and Sporidiobolaceae isolated from Craspedonotus tibialis and mountain soil in Korea

Characterization of two unrecorded yeast species in the families Cystobasidiaceae and Sporidiobolaceae isolated from Craspedonotus tibialis and mountain soil in Korea

The purpose of this study was to isolate and identify wild yeasts from Craspedonotus tibialis samples in Taean-gun and soil samples in Uijeongbu-si, Republic of Korea. Out of the sixteen strains identified, fourteen had been previously recorded, whereas two strains were unrecorded in the Republic of Korea. Identification of wild yeast strains was performed through pairwise sequence comparisons of the D1/D2 region of the 26S rRNA gene using the Basic Local Alignment Search Tool (BLAST) (Fell et al., 2000). Cell morphology was examined using a phase contrast microscope, and assimilation tests were conducted with the API 20C AUX kit. All strains were classified under the phylum Basidiomycota. The two unrecorded yeast strains, CB9-2 and YP99, are classified under the genus Cystobasidium (family Cystobasidiaceae, order Cystobasidiales, class Cystobasidiomycetes) and the genus Rhodosporidiobolus (family Sporidiobolaceae, order Sporidiobolales, class Microbotryomycetes), respectively. These two strains exhibited morphologies consistent with their type species. Both CB9-2 and YP99 cells were oval, and both strains demonstrated polar budding. This study highlighted the morphological and biochemical characteristics of the two unrecorded yeast species that had not been previously documented in Korea.