RESULTS:
1 - 12 of 12 for ""ascomycetous yeast""
Nakazawaea todaengensis f.a., sp. nov., a yeast isolated from a peat swamp forest in Thailand
Strain DMKU-PS11(1)T was isolated from peat in a swamp forest in Thailand. DNA sequence analysis showed that it belonged to a novel species that was most closely related to Nakazawaea laoshanensis. However it differed from the type strain of N. laoshanensis (NRRL Y-63634T) by 2.3 % nucleotide substitutions in the D1/D2 region of the large subunit (LSU) rRNA gene 1.0 % nucleotide substitutions in the small subunit (SSU) rRNA gene and 8.0 % nucleotide substitutions in the internal transcribed spacer (ITS) region. The phylogenetic analyses based on the combined sequences of the SSU and the D1/D2 region and that of the SSU sequences alone confirmed the placement of the novel species in the Nakazawaea clade and its close affinity with N. laoshanensis. Hence the species Nakazawaea todaengensis f.a. sp. nov. is proposed. The type strain is DMKU-PS11(1)T (=CBS 14555T=TBRC 6559T). The MycoBank number for Nakazawaea todaengensis f.a. sp. nov. is MB 819513
Wickerhamomyces menglaensis f.a., sp. nov., a yeast species isolated from rotten wood
Five strains NUNU 16637 NYNU 16645 NYNU 1673 NYNU 1680 and NYNU 1689 of a novel ascomycetous yeast were isolated from the Xishuangbanna tropical rainforest Yunnan Province PR China. The five strains shared identical sequences in both of the D1/D2 domains of the large subunit rRNA gene and the internal transcribed spacer (ITS) regions. Sequence analysis showed that they represent undescribed yeast species belonging to the genus Wickerhamomyces. They differed from their closest known species Wickerhamomyces xylosivorus NBRC 111553T by 3.4 % sequence divergence (14 substitutions and six gaps out of 584 bp) in the D1/D2 domains and by 9.6 % sequence divergence (28 substitutions and 24 gaps over 543 bp) in the ITS regions respectively. The five strains of novel species reproduced asexually; no sexual reproduction could be found. In contrast to W. xylosivorus the novel yeast species were able to assimilate l-arabinose inulin soluble starch d-mannitol and citrate and unable to assimilate trehalose raffinose 5-keto-d-gluconate d-gluconate ethanol ethylamine and cadaverine. Growth was observed at 35 °C. The name Wickerhamomyces menglaensis f.a. sp. nov. is proposed to accommodate these strains with NYNU 1673 as the holotype.
Wickerhamiella osmotolerans sp. nov. and Wickerhamiella tropicalis sp. nov., novel ascomycetous yeast in the family Wickerhamiellaceae
Seven yeast strains DMKU VGT1-14T DMKU VGT1-19T DMKU-JMGT1-28 DMKU-JMGT1-32 DMKU VGT2-06 DMKU VGT2-19 and DMKU VGT6-14 were isolated from a grease trap in Thailand and two strains SJ-1 and SN-102 were isolated from the sea surface microlayer in Taiwan. On the basis of phenotypic characteristics and sequence analysis of the D1/D2 region of the large subunit (LSU) rRNA gene and the internal transcribed spacer (ITS) region these strains represented two novel yeast species of the genus Wickerhamiella. In terms of pairwise sequence similarity four strains DMKU VGT1-14 DMKU-JMGT1-32 DMKU VGT6-14 and SN-102 were closely related to Wickerhamiella infanticola NRRL Y-17858T but differed by 13 nucleotide substitutions with one gap (2.46 %) in the D1/D2 domain of the LSU rRNA gene and 15 nucleotide substitutions with 23 gaps (4.2 %) in the ITS region. The strains DMKU VGT1-19T DMKU-JMGT1-28 DMKU VGT2-06 DMKU VGT2-19 and SJ-1 differed from the type strain of the most closely related species Wickerhamiella sorbophila NRRL Y-7921T by nine nucleotide substitutions with one gap (1.66 %) in the D1/D2 domain of the LSU rRNA gene and nine nucleotide substitutions with 17 gaps (2.52%) in the ITS region. Hence the names Wickerhamiella osmotolerans sp. nov. and Wickerhamiella tropicalis sp. nov. are proposed to accommodate these species in the genus Wickerhamiella. The holotypes are W. osmotolerans DMKU VGT1-14T (ex-type strain TBRC 11425=PYCC 8359=CGMCC 2.6179; Mycobank number 833394) and W. tropicalis DMKU VGT1-19T (ex-type strain TBRC 11426=PYCC 8360=CGMCC 2.6180; Mycobank number 833393).
Inopinatum lactosum gen. & comb. nov., the first yeast-like fungus in Leotiomycetes
Sporobolomyces lactosus is a pink yeast-like fungus that is not congeneric with other members of Sporobolomyces (Basidiomycota Microbotryomycetes Sporidiobolales). During our ongoing studies of pink yeasts we determined that S. lactosus was most closely related to Pseudeurotium zonatum (Ascomycota Leotiomycetes Thelebolales). A molecular phylogenetic analysis using sequences of the ITS region and the small and large subunit (SSU LSU) rRNA genes indicated that four isolates of S. lactosus including three ex-type isolates were placed in Thelebolales with maximum support. A new genus is proposed to accommodate S. lactosus Inopinatum. This is the first pink yeast reported in Leotiomycetes.
Savitreea pentosicarens gen. nov., sp. nov., a yeast species in the family Saccharomycetaceae isolated from a grease trap
Two strains (DMKU-GTCP10-8 and CLIB 1740) representing a novel anamorphic yeast species were isolated from a grease sample collected from a grease trap in Thailand and from an unidentified fungus collected in French Guiana respectively. On the basis of phylogenetic analysis based on the combined D1/D2 domain of the large subunit (LSU) rRNA gene and the internal transcribed spacer (ITS) region Lachancea fermentati CBS 707T was the closely related species with 12.8 % sequence divergence (70 nucleotide substitutions and three gaps in 571 nucleotides) and 28.1 % sequence divergence (93 nucleotide substitutions and 90 gaps in 651 nucleotides) in the D1/D2 domain of the LSU rRNA gene and the ITS region respectively. Phylogenetic analysis based on the concatenated sequences of the five genes including the small subunit rRNA gene the D1/D2 domain of the LSU rRNA gene the ITS region translation elongation factor-1 alpha (TEF1) and RNA polymerase II subunit 2 (RPB2) genes confirmed that the two strains (DMKU-GTCP10-8 and CLIB 1740) were well-separated from other described yeast genera in Saccharomycetaceae. Hence Savitreea pentosicarens gen. nov. sp. nov. is proposed to accommodate these two strains as members of the family Saccharomycetaceae. The holotype is S. pentosicarens DMKU-GTCP10-8T (ex-type strain TBRC 12159=PYCC 8490; MycoBank number 835044).
Clavispora santaluciae f.a., sp. nov., a novel ascomycetous yeast species isolated from grapes
During a study of yeast diversity in Azorean vineyards four strains were isolated which were found to represent a novel yeast species based on the sequences of the internal transcribed spacer (ITS) region (ITS1-5.8S–ITS2) and of the D1/D2 domain of the large subunit (LSU) rRNA gene together with their physiological characteristics. An additional strain isolated from Drosophila suzukii in Italy had identical D1/D2 sequences and very similar ITS regions (five nucleotide substitutions) to the Azorean strains. Phylogenetic analysis using sequences of the ITS region and D1/D2 domain showed that the five strains are closely related to Clavispora lusitaniae although with 56 nucleotide differences in the D2 domain. Intraspecies variation revealed between two and five nucleotide differences considering the five strains of Clavispora santaluciae. Some phenotypic discrepancies support the separation of the new species from their closely related ones such as the inability to grow at temperatures above 35 °C to produce acetic acid and the capacity to assimilate starch. Neither conjugations nor ascospore formation were observed in any of the strains. The name Clavispora santaluciae f.a. sp. nov. is proposed to accommodate the above noted five strains (holotype CBS 16465T; MycoBank no. MB 835794).
Magnusiomyces siamensis sp. nov., a yeast-like fungus isolated from food waste
Three yeast strains DMKU-GTSP8-6 DMKU-GTSP8-14T and DMKU-JED8-73 were isolated from food waste in Thailand. Based on the phenotypic characteristics and sequence analysis of the D1/D2 domain of the large subunit (LSU) rRNA gene and the internal transcribed spacer (ITS) region it was revealed that the three strains clustered with the Magnusiomyces/Saprochaete clade. These strains were distinguished from the closely related species Saprochaete quercus CBS 750.85 Magnusiomyces ovetensis CBS 192.55T Magnusiomyces starmeri CBS 780.96T Saprochaete chiloensis CBS 8187T and Magnusiomyces ingens CBS 517.90T by 11.4 13.1 11.9 11.2 and 12.6 % sequence divergence in the D1/D2 domain and by 34.6 34.5 33.6 33.2 and 34.9 % sequence divergence in the ITS region respectively. The new species which does not produce ascospores is described as Magnusiomyces siamensis. The holotype of Magnusiomyces siamensis is TBRC 15056T and the isotypes are DMKU-GTSP8-14T and PYCC 9023T.
A new yeast genus, Tetrapisispora gen. nov.: Tetrapisispora iriomotensis sp. nov., Tetrapisispora nanseiensis sp. nov. and Tetrapisispora arboricola sp. nov., from the Nansei Islands, and reclassification of Kluyveromyces phaffii (van der Walt) van der Walt as Tetrapisispora phaffii comb. nov
Seven strains of three new yeast species were isolated from soil flowers and leaves in the Nansei Islands Japan. These isolates most closely resembled Kluyveromyces phaffii in physiological characteristics and nuclear DNA base composition (30–32 mol% G+C) but on the basis of DNA-DNA hybridization and electrophoretic karyotyping they were categorized into three new species different from K. phaffii. Phylogenetic analysis using 18S rRNA gene sequence showed that the three new species and K. phaffii were highly related to one another and phylogenetically separate from the members of other species. On the basis of phylogeny and physiological characters it is proposed that the three new species represent novel taxa and should be designated Tetrapisispora iriomotensis gen. nov. sp. nov. (type strain IFO 10929T) Tetrapisispora nanseiensis gen. nov. sp. nov. (type strain IFO 10899T) and Tetrapisispora arboricola gen. nov. sp. nov. (type strain IFO 10925T) while Kluyveromyces phaffii becomes Tetrapisispora phaffii comb. nov.
Metschnikowia ahupensis f.a., sp. nov., a new yeast species isolated from the gut of the wood-feeding termite Nasutitermes sp.
The gut of xylophagous insects such as termites harbours various symbiotic micro-organisms including many yeast species. In a taxonomic study of gut-associated yeasts two strains (ATS2.16 and ATS2.18) were isolated from the gut of the wood-feeding termite Nasutitermes sp. in Maharashtra India. Morphological and physiological characteristics and sequence analyses of the ITS and D1/D2 region of the large subunit rRNA gene revealed that these two strains represent a novel asexual ascomycetous yeast species in the genus Metschnikowia. The species differs from some of its close affiliates in the genus in its inability to utilize ethanol and succinate as the sole carbon source and growth in high sugar concentrations (up to 50 % glucose). In contrast to most members of Metschnikowia the formation of ascospores was not observed on various sporulation media. Moreover whole-genome sequencing was used to further confirm the novelty of this species. When compared with other large-spored Metschnikowia species average nucleotide identity values of 79–80 % and digital DNA–DNA hybridization values of 16–17 % were obtained. The name Metschnikowia ahupensis f.a. sp. nov. is proposed to accommodate this novel yeast species with ATS2.16 as the holotype and strains NFCCI 4949 MTCC 13085 and PYCC 9152 as isotypes. The MycoBank number is MB 844210.
Saturnispora sinensis sp. nov., a new ascomycetous yeast species from soil and rotten wood
A yeast strain (CGMCC 2.6937T) belonging to the ascomycetous yeast genus Saturnispora was recently isolated from soil collected in Xinghuacun Shanxi Province PR China. The strain produces one or two ellipsoid or spherical ascospores in asci formed by the conjugation between a cell and its bud. Phylogenetic analyses of the internal transcribed spacer (ITS) region and the D1/D2 domain of the large subunit rRNA gene suggest that this strain is conspecific with strains NYNU 14639 isolated from rotten wood collected in Funiu Mountain Henan province and ES13S05 from soil collected in Nantou County Taiwan. The CGMCC 2.6937T group is most closely related to Saturnispora dispora and Saturnispora zaruensis. However strain CGMCC 2.6937T differs from S. dispora by 17 (3.2 % 13 substitutions and four gaps) and 77 (18.8 % 52 substitutions and 25 gaps) mismatches and from S. zaruensis by 15 (2.9 % 12 substitutions and three gaps) and 64 (15.6 % 44 substitutions and 20 gaps) mismatches in the D1/D2 domain and ITS region respectively. The results suggest that the CGMCC 2.6937T group represents an undescribed species in the genus Saturnispora for which the name Saturnispora sinensis sp. nov. is proposed. The holotype strain is CGMCC 2.6937T.
Wickerhamiella lachancei f.a. sp. nov., a novel ascomycetous yeast species isolated from flowers of Lantana camara in India
Two isolates representing a novel species of the genus Wickerhamiella were obtained in India from nectar of flowers of Lantana camara an ornamental exotic species native to Central and South America. Phylogenetic analyses of the D1/D2 domain of the 26S large subunit (LSU) rRNA gene internal transcribed spacer (ITS) region and physiological characteristics supported the recognition of the novel species that we designate Wickerhamiella lachancei sp. nov (MycoBank no. MB851709) with MCC 9929T as the holotype and PYCC 10003T as the isotype. Considering pairwise sequence similarity the type strain of the novel species differs from the type strain of the most closely related species Wickerhamiella drosophilae CBS 8459T by 16 nucleotide substitutions and two gaps (3.9 % sequence variation) in the D1/D2 region (560 bp compared) and 28 nucleotide substitutions and five gaps (7.22 % sequence variation) in the ITS region (444 bp compared).
Starmerella fangiana f.a. sp. nov., a new ascomycetous yeast species from Daqu-making environment and other sources
In the survey of yeast diversity in high-temperature Daqu which is a fermentation starter for Chinese sauce-flavoured Baijiu six yeast strains representing one novel species of the genus Starmerella were isolated from samples of Daqu and surrounding environments collected in Zunyi city Guizhou Province China. Phylogenetic analyses of the internal transcribed spacer (ITS) region and the D1/D2 domains of the large subunit rRNA gene indicate that these six strains are conspecific with three other strains isolated from flowers and duckweed collected in Samoa India and Thailand. The representative strain QFC-8 of the new species differs from the closet species Starmerella caucasica resolved by the D1/D2 sequence analysis by 13 (3.1 % 12 substitutions and 1 gap) and 40 (10.3 % 9 substitutions and 31 gaps) mismatches in the D1/D2 domain and ITS region respectively. The results suggest that the novel group represents an undescribed species in the genus Starmerella for which the name Starmerella fangiana sp. nov. is proposed. The holotype strain is CGMCC 2.7773.