Ching-Fu Lee

Hannaella pagnoccae sp. nov., a tremellaceous yeast species isolated from plants and soil.

Several independent surveys of yeasts associated with different plant materials and soil led to the proposal of a novel yeast species belonging to the Tremellales clade (Agaricomycotina, Basidiomycota). Analysis of the sequences of the D1/D2 domains and internal transcribed spacer region of the large subunit of the rRNA gene suggested affinity to a phylogenetic lineage that includes Hannaella coprosmaensis, Hannaella oryzae and Hannaella sinensis. Thirty-two isolates were obtained from different sources, including bromeliads, nectar of Heliconia psittacorum (Heliconiaceae), flowers of Pimenta dioica (Myrtaceae), roots and leaves of sugar cane (Saccharum spp.) in Brazil, leaves of Cratoxylum maingayi, Arundinaria pusilla and Vitis vinifera in Thailand, soil samples in Taiwan, and prairie soil in the USA. Sequence analysis of the D1/D2 domains of the large subunit of the rRNA gene showed that the novel species differs from Hannaella coprosmaensis and Hannaella oryzae by 36 and 46 nt substitutions, respectively. A novel species is suggested to accommodate these isolates, for which the name Hannaella pagnoccae sp. nov. is proposed. The type strain is BI118(T) ( = CBS 11142(T) = ATCC MYA-4530(T)).

Molecular genetic diversity of the Saccharomyces yeasts in Taiwan: Saccharomyces arboricola, Saccharomyces cerevisiae and Saccharomyces kudriavzevii

Genetic hybridization, sequence and karyotypic analyses of natural Saccharomyces yeasts isolated in different regions of Taiwan revealed three biological species: Saccharomyces arboricola, Saccharomyces cerevisiae and Saccharomyces kudriavzevii. Intraspecies variability of the D1/D2 and ITS1 rDNA sequences was detected among S. cerevisiae and S. kudriavzevii isolates. According to molecular and genetic analyses, the cosmopolitan species S. cerevisiae and S. kudriavzevii contain local divergent populations in Taiwan, Malaysia and Japan. Six of the seven known Saccharomyces species are documented in East Asia: S. arboricola, S. bayanus, S. cerevisiae, S. kudriavzevii, S. mikatae, and S. paradoxus.

Trichosporon xylopini sp. nov., a hemicellulose- degrading yeast isolated from the wood-inhabiting beetle Xylopinus saperdioides

Four arthroconidium-producing yeasts were isolated from the gut of wood-inhabiting tenebrionid and passalid beetles. The rRNA genes of these yeast strains were sequenced, compared and analysed. The sequence results and other taxonomic characterizations placed two of the strains into Trichosporon porosum, and the remaining strains, EH024(T) and EH026 which were isolated from Xylopinus saperdioides (Coleoptera: Tenebrionidae), into a novel species of the genus Trichosporon in the Porosum clade. Strain EN6S23 was independently isolated from forest soil in Taiwan and was identified as the same novel species based on identical sequences in the internal transcribed spacers (ITS) and the D1/D2 region of the LSU rRNA gene and similar physiological characteristics to those of strains EH024(T) and EH026. The three strains can assimilate cellulose and xylan as sole carbon source, and are clearly distinguished from their closest taxon, T. porosum, by 14 nt differences in the ITS and D1/D2 region. These strains did not reproduce sexually under the laboratory conditions tested. The novel species is proposed as Trichosporon xylopini sp. nov. (type strain EH024(T)  = ATCC MYA-4670(T)  = CBS 11841(T)).

Candida theae sp. nov., a new anamorphic beverage-associated member of the Lodderomyces clade

Four strains representing a novel yeast species belonging to the genus Candida were independently isolated in Taiwan and Ecuador. Two strains (G17(T) and G31) were isolated in Taiwan, by pellet precipitation from plastic-bottled tea drinks produced in Indonesia, while two additional strains (CLQCA 10-049 and CLQCA 10-062) were recovered from ancient chicha fermentation vessels found in tombs in Quito, Ecuador. These four strains were morphologically, and phylogenetically identical to each other. No sexual reproduction was observed on common sporulation media. Large-subunit (LSU) rRNA gene sequence analysis revealed the four strains to belong to the Lodderomyces clade, closely related to members of the Candida parapsilosis species complex. The four strains, which have identical LSU D1/D2 sequences, differ from their closest phylogenetic neighbors, Candida orthopsilosis and Candida parapsilosis, by 6-9 nt substitutions, respectively. Physiologically, the four strains are similar to Candida parapsilosis, although they can be distinguished from their closest relative by the assimilation of arbutin, nitrite, and creatine. The Indonesian and Ecuadorian strain sets can also be distinguished from one another based on ITS sequencing, differing by 4 substitutions in ITS1 and 1 single nucleotide indel in ITS2. Collectively, the results indicate that the four strains represent a previously unrecognized species of Candida. The name Candida theae sp. nov. is proposed to accommodate these strains, with G-17(T) (BCRC 23242(T)=CBS 12239(T)=ATCC MYA-4746(T)) designated as the type strain.

Five novel species of the anamorphic genus Candida in the Cyberlindnera clade isolated from natural substrates in Taiwan.

Twelve strains representing five novel yeast species were isolated from natural samples distributed in mountain areas in Taiwan during 2007 and 2009. Sequence analysis of the D1/D2 domain of the large subunit (LSU) rRNA gene revealed that these species are members of the Cyberlindnera clade. These five new species have a greater than 1% difference from their closest relatives in the sequences of the D1/D2 domain of the LSU rRNA gene and were well separated from their closest relatives in terms of physiological characteristics. Moreover, a sexual state could not be found in these five novel yeast species. Therefore, the scientific names of Candida maesa sp. nov. (type strain GJ8L01T), Candida takata sp. nov. (type strain EN25S01T), Candida taoyuanica sp. nov. (type strain GY15S07T), Candida hungchunana sp. nov. (type strain NC3W71T) and Candida stauntonica sp. nov. (type strain GY13L05T) were proposed to accommodate these yeasts.

Cyberlindnera xylosilytica sp. nov., a xylitol-producing yeast species isolated from lignocellulosic materials.

Independent surveys of yeasts associated with lignocellulosic-related materials led to the discovery of a novel yeast species belonging to the Cyberlindnera clade (Saccharomycotina, Ascomycota). Analysis of the sequences of the internal transcribed spacer (ITS) region and the D1/D2 domains of the large subunit rRNA gene showed that this species is related to C. japonica, C. maesa and C. easanensis. Six isolates were obtained from different sources, including rotting wood, tree bark and sugar cane filter cake in Brazil, frass from white oak in the USA and decayed leaf in Taiwan. A novel species is suggested to accommodate these isolates, for which the name C. xylosilytica sp. nov. is proposed. The type strain of C. xylosilytica sp. nov. is NRRL YB-2097(T) ( = CBS 13984(T) = UFMG-CM-Y347(T)) and the allotype is UFMG-CM-Y409 ( = CBS 14083). The novel species is heterothallic and complementary mating types are represented by the type and allotype strains. The MycoBank number is MB 811428.

Five novel anamorphic, ascomycetous yeast species associated with mushrooms and soil

Five novel yeast species belonging to the Kodamaea clade are proposed in this paper based on nine strains isolated from mushrooms and soil in Taiwan between 2007 and 2008. These nine yeast strains were found to represent five novel yeast species based on their D1/D2 domain sequences of the large subunit (LSU) rRNA gene and physiological characteristics. Sequence analysis of the D1/D2 domain of the LSU rRNA gene revealed that the five species are phylogenetically related to Kodamaea and Candida sp. clustered into the Kodamaea clade in the phylogenetic tree. All the species reproduced asexually, and no ascospores could be found. Therefore, the scientific names of Candida alishanica sp. nov., Candida hsintzibuensis sp. nov., Candida kaohsiungensis sp. nov., Candida lidongshanica sp. nov., and Candida smagusa sp. nov. were proposed to accommodate these strains. Strains of the first species were discovered from soil; two strains of the second species were isolated from soil and the fruiting body of a mushroom, respectively; and strains of the latter three species were recovered from fruiting bodies of mushrooms. The type strains are listed as follows: C. alishanica GY43S11(T) (=CBS 11429(T) =BCRC 23188(T) ); C. hsintzibuensis EJ7S06(T) (=CBS 11427(T) =BCRC 23183(T) ); C. kaohsiungensis GJ10M01(T) (=CBS 11435(T) =BCRC 23197(T) ); C. lidongshanica SD5S01(T) (=CBS 11426(T) =BCRC 23191(T) ); and C. smagusa EN4M03(T) (=CBS 11430(T) =BCRC 23186(T) ).

Diversity of yeasts associated with the sea surface microlayer and underlying water along the northern coast of Taiwan.

Yeast communities inhabiting the sea surface microlayer (SSML) on the northern coast of Taiwan were examined using a cultivation method and compared with those inhabiting the underlying water (UW) at a 50-cm depth. Culturable yeasts were recovered from the SSML and UW samples collected in the morning during 4 field campaigns, and 420 strains were isolated. The 420 isolates were grouped into 43 species using a polyphasic molecular approach, including sequence analysis of the 26S rDNA D1/D2 domain and 5.8S-ITS region. From the SSML samples, 12 genera and 39 species, including 7 new species of Cryptococcus sp. (1), Candida spp. (4), and Rhodotorula spp. (2), were isolated. From the UW samples, 10 genera and 21 species, including one new species of Rhodotorula sp. (1), were isolated. Rhodotorula mucilaginosa was the most abundant species present in the yeast community in SSML (37.6%) and UW (21.6%) samples. Basidiomycetous yeasts (63.6%) and pigmented yeasts (64.5%) comprised the major yeast population. The yeast community in the SSML had a higher species number and abundance than the UW. Moreover, although the majority of yeast community species were from the SSML, individual species distribution in the SSML was unequal.

Candida gosingica sp. nov., an anamorphic ascomycetous yeast closely related to Scheffersomyces spartinae

During surveys on yeast diversity in forest soils from Taiwan and Thailand, ten yeast strains isolated from different samples were found to have similar molecular and physiological characteristics. Sequence analysis of small subunit (SSU) rDNA, the D1/D2 domain of large subunit (LSU) rDNA and internal transcribed spacer (ITS)-5.8S rDNA demonstrated that these strains were closely related to Scheffersomyces spartinae. The novel strains could be differentiated from S. spartinae by a 0.9  % sequence divergence (5 substitutions, 0 gaps) in the D1/D2 domain of LSU rDNA, a 1.5  % divergence (8 substitutions, 0 gaps) in the ITS-5.8S rDNA and a 0.7  % divergence (12 substitutions, 2 gaps) in the SSU rDNA. The novel strains also showed specific patterns of electrophoretic karyotypes that differed from that of S. spartinae. Therefore, a novel yeast species, Candida gosingica sp. nov., is proposed to accommodate these strains. The type strain SJ7S11(T) (=BCRC 23194(T)=CBS 11433(T)) was assigned and deposited in the Bioresource Collection and Research Center (BCRC), Food Industry Development and Research Institute, Hsinchu, Taiwan, and Centraalbureau voor Schimmelcultures (CBS), Utrecht, The Netherlands.

Cryptococcus keelungensis sp. nov., an anamorphic basidiomycetous yeast isolated from the sea-surface microlayer of the north-east coast of Taiwan

Strain SN-82(T) was isolated from the sea-surface microlayer at Keelung on the north-east coast of Taiwan. Sequence analysis of the D1/D2 domain of the 26S rDNA of strain SN-82(T) suggested that this strain is related to the aerius clade in the Filobasidiales. Phenotypic characteristics such as the absence of sexual structures and ballistoconidia, the assimilation of myo-inositol and d-glucuronate, the inability to ferment glucose, the possession of coenzyme Q-10 and positive Diazonium blue B and urease reactions also indicated that this strain belongs to the genus Cryptococcus. However, divergences of more than 3.6 % were observed in the D1/D2 domain when compared with other described Cryptococcus species, which indicated that the isolated yeast represents a previously unrecognized member of this genus. Therefore, the novel yeast species Cryptococcus keelungensis sp. nov. is proposed, with strain SN-82(T) (=CBS 10876(T) =BCRC 23107(T) =JCM 14893(T)) as the type strain.