• Korean Journal of Microbiology
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• v.31 no.3
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• pp.197-202
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• 1993

The budding yeast S. cerevisiae contains 10-nm filament ring that lies just inside the plasma memhrane in the region of the mother-bud neck. It is possihle that CDC3. CDCIO, CDCII. CDCI2 genes encode the filaments. Recently it has been shown that the CDC3 and CDCI2 gene products arc localized to [he vicinity of the neck lilaments by immunolluorescence. However. the role of the lilament ring is not clear. In order to find out the role of filament ring. I have tried to clone the similar gene in S. pomhe to the CDC3 in S. cerevisiae. Genomic library was constructed by use of $\lambda$gtll expression vector and screened with CDC3 antibodies. From sequencing data, there were more than two introns in the newly cloned gene. There was 62% homology between the part of the predicted amino acid sequence of cloned gene and CDC3 amino acid sequence.

• KSBB Journal
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• v.4 no.2
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• pp.172-176
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• 1989

The alcohol fermentation was carried out to study the effect of aeration and unsaturated fatty acids added on the ethanol tolerance of Saccharomyces cerevisiae STV89 and Kluyveromyces fragilis CBS397. The cell growth rate and ethanol production rate was stimulated by aeration and the cell mass production and ethanol production were also substantially improved. With respect to strains, the maximum specific growth rate and overall ethanol productivity of K. fragilis under aerated condition were 6.4 fold and 4.4 fold higher than those of strictly anaerobic condition, although those of S. cerevisiae were increased 1.7 times and 2.3 times by aeration. The addition of ergosterol, linoleic acid and oleic acid also improved the cell growth and ethanol production of S. cerevisiae and K. fragilis. Thus it was found that oxygen and unsaturated fatty acids added played a decisive role on the increase of ethanol tolerance of yeast strains.

• Food Science and Preservation
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• v.30 no.6
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• pp.1029-1042
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• 2023

This study aimed to apply the technology of increasing the volatile aromatic compounds in wine through mixed fermentation of Saccharomyces cerevisiae and non-Saccharomyces yeasts to make distilled soju. The expectation was to induce changes in metabolites such as volatile aromatic compounds before the distillation process, followed by concentrating these compounds through distillation to enhance the odor property of distilled soju. Additionally, the study aimed to examine the impact of mixed fermentation with S. cerevisiae and non-Saccharomyces yeasts on distilled soju's free amino acid content. As a result, when Hanseniaspora uvarum yeast was used, there was an increase in the content of low molecular weight volatile aroma compounds, particularly esters. Distilled soju co-fermented with S. cerevisiae and H. uvarum SJ69 exhibited similar amino acid content to distilled soju single-fermented with S. cerevisiae. However, distilled soju co-fermented with S. cerevisiae and H. uvarum S6, a decrease in amino acid content. Sensory evaluation results indicated a higher odor score in distilled soju co-fermented with S. cerevisiae and H. uvarum S6, suggesting that the mixed fermentation technology utilizing H. uvarum could contribute to improving the quality of distilled soju in the future.

• Korean Journal of Microbiology
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• v.47 no.2
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• pp.167-169
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• 2011

The Saccharomyces cerevisiae S288c strain does not show haploid and diploid filamentous growth, and biofilm formation, because it has a flo8 nonsense mutation unlike ${\Sigma}1278b$ strain which has a FLO8 gene. During the heat stress experiments to investigate the role of ScKns1, LAMMER kinase in S. cerevisiae, we found that ${\Sigma}1278b$ strain revealed heat sensitivity at $37^{\circ}C$, a mild heat stress in contrast to S288c strain. We also found that the disruption of ScKns1 and the addition of sorbitol suppress heat sensitivity of ${\Sigma}1278b$ strain. These results suggest the possibility that Flo8 and ScKns1 may interact to transducer a signal for regulating heat stress through a novel signaling pathway.

• The Korean Journal of Mycology
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• v.27 no.3 s.90
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• pp.181-186
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• 1999

Osmotolerant yeast isolated from soy paste could grow on media with 2 M NaCl. This strain was identified as Zygosaccharomyces rouxii by biological characteristics, RFLP of ribosomal DNA and mating with compatible haploid strain. Growing rate of the Z. rouxii YDJ was slower than Saccharomyces cerevisiae. Z. rouxii YDJ accumulated trehalose, which is known as one of the osmolytic protectants, in cells cultured on media with salt. Enzyme activity of trehalose phosphate synthase related to trehalose biosynthesis of the YDJ was lower than those of S. cerevisiae. Trehalase activity related trehalose degradation was also lower in Z. rouxii YDJ than S. cerevisiae. However, as Z. rouxii accumulated trehalose by salt treatment, salt tolerancy of Z. rouxii was assumed to be related to trehalose in additon to glycerol.

• Journal of Animal Science and Technology
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• v.49 no.6
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• pp.819-828
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• 2007

Two experiments were conducted to observe the effects of direct fed microbials on metabolic characteristics in sheep and milking performance in dairy cows. A metabolic trial with four ruminally cannulated sheep(60±6kg) was conducted in a 4×4 Latin square design to investigate the supplementation effects of Saccharomyces cerevisiae, Clostridium butyricum or mixed microbes of S. cerevisiae and C. butyricum on ruminal fermentation characteristics and whole tract digestibility. Sheep were fed 1.25 kg of total mixed ration(TMR, DM basis) supplemented with S. cerevisiae (2.5g/day), C. butyricum (1.0g/day) or its mixture(S. cerevisiae 1.25g/day+C. butyricum 1g/day), twice daily in an equal volume. But control sheep were fed only TMR. A feeding trial with 28 lactating Holstein cattle was also conducted for 12 weeks to investigate the effects of the same microbial supplements as for the metabolic trial on milking performance. The cows were fed the TMR(control), and fed S. cerevisiae(50g/day), C. butyricum(15g/day) or its mixture (S. cerevisiae 25g/day + C. butyricum 7.5g/day) with upper layer dressing method. Total VFA concentration and the digestibility of whole digestive tract in the sheep increased by supplementation of S. cerevisiae, C. butyricum or their combined microbials compare to control group. The proportion of propionic acid at 1h(P<0.039) and 3h(P<0.022) decreased by supplementation of S. cerevisiae while tended to increase acetic acid proportion at the same times. Daily dry matter intake(DMI) was not influenced by the microbial treatments, but milk yield(P<0.031) and feed efficiency(milk yield/DMI, P<0.043) were higher for the cow received C. butyricum than those for other treatments. The milk fat content was higher (P<0.085) when cows fed S. cerevisiae(4.11%) than that fed the control (4.08%), the diets with C. butyricum (3.85%) and the microbial mixture. Based on the results obtained from the current experiments, supplementation of C. butyricum or mixture with S. cerevisiae might be increased milk fat content and milk productivity of lactating daily cows. (Key words:Saccharomyces cerevisiae, Clostridium butyricum, Fermentation characteristics,

• Journal of Microbiology and Biotechnology
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• v.30 no.12
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• pp.1854-1861
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• 2020

Staphylococcus aureus is one of the most common microorganisms and causes foodborne diseases. In particular, biofilm-forming S. aureus is more resistant to antimicrobial agents and sanitizing treatments than planktonic cells. Therefore, this study aimed to investigate the anti-biofilm effects of cell-free supernatant (CFS) of Saccharomyces cerevisiae isolated from cucumber jangajji compared to grapefruit seed extract (GSE). CFS and GSE inhibited and degraded S. aureus biofilms. The adhesion ability, auto-aggregation, and exopolysaccharide production of CFS-treated S. aureus, compared to those of the control, were significantly decreased. Moreover, biofilm-related gene expression was altered upon CFS treatment. Scanning electron microscopy images confirmed that CFS exerted anti-biofilm effects against S. aureus. Therefore, these results suggest that S. cerevisiae CFS has anti-biofilm potential against S. aureus strains.

• Microbiology and Biotechnology Letters
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• v.16 no.6
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• pp.489-493
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• 1988

To obtain a new yeast strain that is able to efficiently produce ethanol from starch, the glucoamylase gene of Saccharomyces diastaticus was transformed into S. cerevisiae without a cloning vector. The competent cells of S. cerevisiae, induced by the treatment of Li$_2$SO$_4$, were transformed with the partial BamHI-digests of chromosomal DNA of S. diastaticus, and the transformants were selected by their abilities to utilize and ferment starch. The transformants, which appeared at a frequency of 8.5$\times$10$^{-7}$, were able to withstand up to 800 ppm of copper sulfate like the recipient and retained the phenotypic expression of the recipient with the exception of the acquisition of STA gene and MAL gene, as regards fermentation of carbohydrates. The enzymatic properties of glucoamylases produced by transformants were very similar to those produced by S. diastaticus as based on optimium pH and temperature.

• Mycobiology
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• v.38 no.3
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• pp.206-209
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• 2010

To produce bioactive compound enriched yeast using medicinal Gugiga (Lycium chinensis Mill), several edible Saccharomyces species were cultured in Gugija extracts added yeast extract, peptone and dextrose medium (GE - YEPD medium) at $30^{\circ}C$ for 24 hr, and their growth were determined. Growth of Saccharomyces cerevisiae K-7 and Sacchromyces cerevisiae ACTC 7904 were better than those of the other yeasts. Two yeasts were selected and then determined their some physiological functionalities after cultivated the yeasts in the GE - YEPD medium and compared those grown on YEPD medium. Antihypertensive angiotensin I-converting enzyme (ACE) inhibitory activity of S. cerevisiae K-7 grown on GE - YEPD medium was about 20% higher than that grown on YEPD medium. Superoxide dismutase-like activity of S. cerevisiae ACTC 7904 was also about 12% more high. However, the other physiological functionalities were almost same or lower. Optimal addition concentration of Gugija extract was 10%, and maximally growth and ACE inhibitory activity of S. cerevisiae K-7 were shown when the strain was cultured in 10% Gugija extracts containing YEPD medium at $30^{\circ}C$ for 12 hr.

• Journal of Microbiology and Biotechnology
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• v.12 no.3
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• pp.411-416
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• 2002

Bacillus macerans cyclodextrin glucanotransferase (CGTase) was expressed on the cell surface of Saccharomyces cerevisiae by fusing with Aga2p linked to the membrane-anchored protein, Aga1p. The surface display of CGTase was confirmed by immunofluorescence microscopy and its enzymatic ability to form ${\alpha}$-cyclodextrin from starch. The maximum surface-display of CGTase was obtained by growing recombinant S. cerevisiae at $20^{\circ}C$ and pH 6.0. S. cerevisiae cells displaying CGTase on their surface consumed glucose and maltose, inhibitory byproducts of the CGTase reaction, to enhance the purity of produced cyclodextrins. Accordingly, the experimental results described herein suggest a possibility of using the recombinant S.cerevisiae anchored with bacterial CGTase on the cell surface as a whole-cell biocatalyst for the production of cyclodextrin.