Lachancea quebecensis sp. nov., a yeast species consistently isolated from tree bark in the Canadian province of Québec

A thorough sampling of maple, oak, birch, and apple tree bark in North America yielded a set of isolates that represent a yeast species not yet formally described. The strains obtained were all isolated from the Canadian province of Québec. These four isolates have identical electrophoretic karyotypes, distinct from other species of the genus Lachancea, and are most closely related to the formally recognized species Lachancea thermotolerans according to the D1/D2 domain of the LSU rDNA gene and 5.8S–ITS region. Previous studies revealed the existence of a population of strains closely related to L. thermotolerans, with unique D1/D2 sequences and the ability to grow on melibiose, which is also true for these isolates. The sequences obtained here (for the D1/D2, and 5.8S–ITS region) are identical among the four strains, and in a phylogenetic analysis of the D1/D2 region, the strains form a distinct clade with the previously described population closely related to L. thermotolerans, composed of isolates from Japan, as well as from the provinces of Ontario and Québec in Canada. On the basis of select physiological and phylogenetic characteristics, a novel ascosporogenous yeast species, Lachancea quebecensis sp. nov., is proposed. The type strain LL11_022T ( = CBS 14138T = CLIB 1763T = UCDFST 15-106T) was isolated from maple tree bark in the Station Duchesnay, QC region of Québec, Canada. The MycoBank number is MB811749.

Tetrapisispora taiwanensis sp. nov. and Tetrapisispora pingtungensis sp. nov., two ascosporogenous yeast species isolated from soil

Two novel yeast species, Tetrapisispora taiwanensis sp. nov. and Tetrapisispora pingtungensis sp. nov., belonging to the Saccharomycetaceae within the Saccharomycetales, are proposed to accommodate six strains isolated from samples of Taiwanese forest soil between 2005 and 2010. Sequence analysis of the internal transcribed spacer (ITS) and the D1/D2 domains of the large-subunit (LSU) rRNA gene revealed that the two species are phylogenetically closely related to species of the genus Tetrapisispora. Moreover, the assimilation spectrum of carbon and nitrogen sources and morphological characteristics are very similar to those of other Tetrapisispora species. The molecular, morphological and physiological characteristics described above indicate that these two species should be classified as members of the genus Tetrapisispora. The two species can be differentiated from each other and from other Tetrapisispora species based on their LSU D1/D2 rRNA gene and ITS sequences. Thus, the two species could be regarded as novel species of the genus Tetrapisispora, and the names Tetrapisispora taiwanensis sp. nov. (type strain SJ6S04T = CBS 10586T = NBRC 102652T = BCRC 23090T) and Tetrapisispora pingtungensis sp. nov. (type strain NC2S06T = CBS 12780T = BCRC 23409T) are proposed. The type strains of the two species were isolated from forest soil in Leinhuatsu Park, Nantou, in 2006 and from Hungchun, Pingtung, in 2009, respectively.

Lachancea lanzarotensis sp. nov., an ascomycetous yeast isolated from grapes and wine fermentation in Lanzarote, Canary Islands

During the characterization of the microbiota biodiversity associated with grapes and wineries in different bioclimatic conditions of the Canary Islands (Spain), a novel yeast species was isolated from Lanzarote, the driest wine-producing region of the archipelago. Seven strains isolated from grapes, microvinifications and wineries are described. Sequence analysis of the D1/D2 domain of the LSU rDNA gene and 5.8S-ITS regions revealed that the isolates were phylogenetically a member of the genus Lachancea and are closely related to Lachancea meyersii NRRL Y-27269T and Lachancea nothofagi NRRL Y-48670T. On the basis of morphological, biochemical and physiological characterization and phylogenetic analysis, a novel ascosporogenous yeast species, Lachancea lanzarotensis sp. nov., is proposed. The type strain is L2C-15T ( = CBS 12615T = CECT 13066T) which was isolated from grape berries of Vitis vinifera L. cv. Listán Negro red grape variety in Tinajo, Lanzarote. The MycoBank no. is MB 801390.

Zygosaccharomyces gambellarensis sp. nov., an ascosporogenous yeast isolated from an Italian ‘passito’ style wine

Yeast strains were isolated from Vin Santo of Gambellara, a sweet white wine with the specificity of Controlled Designation of Origin produced from off-vine overripened grapes in the Veneto region (Italy). Comparative sequence analysis of the 26S rRNA gene revealed that three representative strains (ZO03-5T, CA06-8 and ME06-9) constitute a taxon related to, but distinct from, Zygosaccharomyces machadoi. Similarity between the 26S rRNA gene domain D1/D2 sequence of the three isolates and Z. machadoi was 97.9 %; moreover, the morphological characteristics and the physiological behaviour also supported recognition of a novel taxon of osmophilic non-psychrophilic yeast showing a flower-like arrangement of budding cells that remain attached to each other. The name Zygosaccharomyces gambellarensis is proposed for the novel species, with ZO03-5T ( = CBS 12191T = MUCL 53393T) as the type strain.