Cystobasidium tubakii and Cystobasidium ongulense, new basidiomycetous yeast species isolated from East Ongul Island, East Antarctica

Two new cold-adapted yeast species, Cystobasidium tubakii sp. nov. and Cystobasidium ongulense sp. nov., were isolated from soil collected from East Ongul Island, East Antarctica, during the 49th Japanese Antarctic Research Expedition (JARE 49). Molecular analysis based on large subunit (LSU) D1/D2 domain and the combined sequences of small subunit (SSU) rDNA, internal transcribed spacer (ITS) region, LSU D1/D2 domain and TEF1 sequences showed that these species are novel. Both species could grow at sub-zero temperatures and in vitamin-free media. These characteristics were likely obtained by the yeasts to survive oligotrophic environments such as that in Antarctica. This is the first report of new fungal species isolated from near the Syowa station in the 60-y history of JARE.