• Journal of Life Science
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• v.11 no.2
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• pp.133-137
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• 2001

The molecular taxonomic relationship of nine species in the genus Moniliella Stolk & Dakin and Trichosporonoides Haskins & Spencer and six species of other yea나-like fungi was examined by sequencing analysis of large subunit rDNA D1/D2 variable domain. The fifteeen species fell into two major groups corresponding with their genetic relationships. The nine species of the genus Moniliella and Trichosporonoides were placed at the same cluster. similarity values based on the D1/D2 domain sequences were 45.4-100% among species of genus Moniliella, 45.2-84.4% among genus Trichosporonoides species, and 45.6-90.1% among species of genus Moniliella and Trichosporonoides. Identical sequence similarity was observed between M. suaveolens var. nigra and M. suaveolens. A colse relationship of M. mellis. and M. acetoabutens is observed. The result of this study provided and insight into the genetic origins of genus Moniliella and Trichosporonoides species as well as their genetic relationships. Genus Moniliella and Trichosporonoides are closely related to each other based on sequence analysis of the large subunit rDNA D1/D2 region and we suggest combination of the genus Moniliella and Trichosporonoides to single genus.

• Journal of Microbiology and Biotechnology
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• v.26 no.4
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• pp.700-709
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• 2016

The mitogen-activated protein kinase HOG1 (high-osmolarity glycerol response pathway) plays a crucial role in the response of yeast to hyperosmotic shock. Trichosporonoides oedocephalis produces large amounts of polyols (e.g., erythritol and glycerol) in a culture medium. However, the effects of HOG1 gene knockout and environmental stress on the production of these polyols have not yet been studied. In this study, a To-HOG1 null mutation was constructed in T. oedocephalis using the loxP-Kan-loxP/Cre system as replacement of the targeted genes, and the resultant mutants showed much smaller colonies than the wild-type controls. Interestingly, compared with the wild-type strains, the results of shake-flask culture showed that To-HOG1 null mutation increased erythritol production by 1.44-fold while decreasing glycerol production by 71.23%. In addition, this study investigated the effects of citric acid stress on the T. oedocephalis HOG1 null mutants and the wild-type strain. When the supplementation of citric acid in the fermentation medium was controlled at 0.3% (w/v), the concentration of erythritol produced from the wild-type and To-HOG1 knockout mutant strains improved by 18.21% and 21.65%, respectively.

• Biomedical Science Letters
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• v.3 no.2
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• pp.77-82
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• 1997

One of the most important prerequisites of the industrial microorganism is that it should not be virulent to humans or economically important animals or plants. In this investigation, the microbiological characterization of T. madida N-5-3 strain was performed. And then, the virulence of the test strain in mouse model was examined systematically. The microbiological characteristics of the test strain were found to be fully consistent with those of typical T. madida. The i.p. lethal dose(LD)$_{50}$ of the test strain was greater than 1$\times$10$^8$, because there was no dead animal with the challenge doses upto the level of 1$\times$10$^8$. When 1$\times$10$^8$ yeast cells were challenged to the laboratory mice, T. madida N-5-3 strain was completely cleared from the liver and spleen in 4 days after challenge. And no pathological changes in the histological examination of the internal organs from challenged mice was observed. Above results can provide the predictability of the safety of T. madida N-5-3 strain for the industrial use in the view point of the public health aspect.