Vanderwaltozyma japonica sp. nov.: a novel yeast isolated from subtropical regions in Japan

Seven yeast strains, NBRC 11072, NBRC 11076, NBRC 11078^T, NBRC 11080, NBRC 116645, NBRC 116646 and NBRC 116647, were isolated from the subtropical regions of Japan. The seven strains share identical nucleotide sequences in the D1/D2 domains of the large subunit (LSU) rRNA gene and internal transcribed spacer (ITS) regions. Six strains (NBRC 11072, NBRC 11076, NBRC 11078^T, NBRC 11080, NBRC 116645 and NBRC 116646) share identical mitochondrial cytochrome c oxidase subunit II (COX II) sequences as well, while NBRC 116647 differs from them by one substitution in this region. The yeast strains were closely related to Vanderwaltozyma verrucispora NBRC 1884^T in the ITS regions. However, in the D1/D2 domains and COX II, they were closely related to Torulaspora globosa CBS 764^T and Naumovozyma castellii NRRL Y-12630^T, respectively. They differed from V. verrucispora by 49 nucleotide substitutions with 26 gaps in the ITS region, from T. globosa by 19 nucleotide substitutions with 3 gaps in the D1/D2 domains and from N. castellii by 49 nucleotide substitutions with 6 gaps in the COX II. The phylogenetic analysis of the seven strains based on the sequences of the D1/D2 domains of LSU and ITS regions among related species showed that these strains represent a single novel species within the genus Vanderwaltozyma. The seven strains could be differentiated from other known species of the genus Vanderwaltozyma because of their inability to assimilate glycerol as a carbon source. Therefore, we suggest that these seven strains represent a novel species, designated Vanderwaltozyma japonica sp. nov. The holotype is NBRC 11078^T (isotype: TBRC 19102^T). The MycoBank number is MB 855476.