• Microbiology and Biotechnology Letters
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• v.36 no.2
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• pp.158-164
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• 2008

The fusants which contain starch utilizing ability and alcohol fermenting ability were developed by protoplast fusion of Saccharomyces cerevisiae KOY-1 and Saccharomyces diastaticus KCTC 1804. Sacharomyces cerevisiae KH-12 was obtained by haploid induction from Saccharomyces cerevisiae KOY-1. The auxotropic mutants of yeast were obtained by using an ethylmethane sulfonate (EMS). The frequency of protoplast formation in Saccharomyces cerevisiae KOY-1 $(Met^-)$ and Saccharomyces diastaticus KCTC 1804 $(Trp^-)$ were 90.5% and 97.7%, respectively. The frequency of fusant formation was $1.79{\times}10^{-4 }$ for the regenerated protoplast and the 1,000 fusants were obtained. Fusant FA 776 was selected as a potential yeast which contain an alcohol fermenting ability in the starch medium. The genetic stability was 4.64% for 10 passages of generation. Fusant FA 776 produced 13mg/ml of alcohol in 24% starch medium and showed 1.86-fold higher alcohol fermenting ability than Saccharomyces diastaticus KCTC 1804.

• Korean Journal of Microbiology
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• v.40 no.2
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• pp.73-80
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• 2004

Coenzyme Q is a quinone derivative that acts as a lipid electron carrier in the respiratory chain located at mito-chondrial inner membrane in eucaryotes or plasma membrane in procaryotes and also functions as antioxidant. A putative Neurospora crassa coq-4 gene was cloned and functionally expressed in Saccharomyces cerevisiae coq4 mutant. Complemented S. cerevisaie mutant strain was able to produce coenzyme $Q_{6}$ and showed a normal growth rate. They also showed less sensitivities to polyunsaturated fatty acids such as linoleic acid or linolenic acid. The predicted sequence of N. crassa COQ4 is consisted of 347 amino acids with a molecular mass of 39.7 kDa and showed 35% identity and 52% similarity with that of S. cerevisiae.

• The Korean Journal of Mycology
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• v.40 no.1
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• pp.60-64
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• 2012

Physiological functionalities of culture concentrates from various fungi were investigated. The culture concentrates from Saccharomyces cerevisiae Y277-3 showed the highest tyrosinase inhibitory activity of 42.7%. Among mold physiological functionalities, the culture concentrates from Aspergillus orygae CN20-3-1-4 showed the highest antioxidant activity of 15.8%. The other functionalities of fungi were very low or not detected. The intracellular tyrosinase inhibitor from Saccharomyces cerevisiae Y277-3, which showed the highest physiological functionalities was maximally produced when the strain was cultured in PD broth at $30^{\circ}C$ for 24 h.

• Microbiology and Biotechnology Letters
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• v.30 no.4
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• pp.293-297
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• 2002

The cyclodextrin glucanotransferase (CGTase) gene from Bacillus stearothermophilus NO2 was expressed in Saccharomyces cerevisiae 2805 under the adhl promoter. The CGTase was purified from S. cerevisiae 2805/pVT-CGTS. The purified enzyme exhibited a optima of activity around pH 7.0 and $65^{\circ}C$. Thermal stability of the enzyme was increased fairly as compared with the CGTase of B. stearothermophilus NO2. The conversion yield of cyclodextrin (CD) and the production ratio of $\alpha$-, $\beta$,-, ${\gamma}$-CD from starch were showed similarly aspect to the CGTase of B. stearothermophilus NO2.

• The Korean Journal of Mycology
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• v.39 no.3
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• pp.227-228
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• 2011

Fibrinolytic activities of culture concentrates of various yeasts were investigated. The concentrates of the culture broth of Saccharomyces cerevisiae Y99-7 showed the strongest fibrinolytic activity of 25 mm (clear zone). The fibrinolytic activity of Saccharomyces cerevisiae Y99-7 was more high in the culture concentrates from PD broth rather than that of yeast extract-peptone dextrose cultures (clear zone : 22.7 mm).

• Journal of Microbiology and Biotechnology
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• v.16 no.12
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• pp.1904-1911
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• 2006

The cell-free extracts of 250 yeasts were screened for their in vitro anti-angiogenic activity, to develop a new cancer metastasis inhibitor. Saccharomyces cerevisiae K-7 was selected as the producer of the anti-angiogenic agent, because it had the highest anti-angiogenic activity. The anti-angiogenic agent was produced maximally from hydrolysates of Saccharomyces cerevisiae K-7, when the yeast was cultured in yeast extract-peptone-dextrose medium at 30$^{\circ}C$ for 24 h, and cell-free extracts were than digested with pepsin for 4 h at 37$^{\circ}C$. The anti-angiogenic agent was further purified by ultrafiltration, Sephadex G-25 gel permeation chromatography and reverse-phase HPLC, and the anti-angiogenic activity of the final purified preparation was 72.7% at 10 $\mu$M/egg. The purified anti-angiogenic agent was found to originate from the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) molecule of Saccharomyces cerevisiae K-7, and its peptide sequence was Val-Ser-Trp-Tyr-Asp-Asn-Glu-Tyr-Gly-Tyr-Ser-Thr-Arg-Val-Val-Asp. In the MTT assay, the shape of the HT-l 080 cell was clearly changed to a circular type at 0.2 mM purified anti-angiogenic agent. This result indicated that the growth of the HT-I080 cell was significantly inhibited at 0.2 mM of the purified anti-angiogenic agent. The MMP activity of the treated HT-l080 cells was not affected, evidenced by the gelatin zymography, indicating that the anti-angiogenic mechanism of the purified anti-angiogenic agent is not mediated through MMP activity.

• 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.

• Korean Journal of Microbiology
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• v.43 no.3
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• pp.217-221
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• 2007

The domestic cultured Campbell's Early and Geubong grapes were fermented far the production of red wines with the isolated wild yeast Saccharomyces cerevisiae IJ850. For the isolation of wild yeast, Geubong and Campbell's Early grapejuices were naturally fermented at room temperature for 6 days without adding stater culture. The strain isolated from Geubong which has 1.8 times higher fermentative ability than the strains isolated Campbell Early was selected. The selected strain was identified by using 26S rDNA sequencing. The strain showed 99.7% of similarity with Saccharomyces cerevisiae and thus identified as Saccharomyces cerevisiae IJ850. It was investigated the fermentative ability as the start culture. For the production of grapewine, the final sugar concentrations of grapejuices were adjusted to the $25^{\circ}Brix$ with anhydrous glucose. The grapejuices were fermented at room temperature for 10 days in the air-locked bottles filled with $CO_2$ gas. The final yield and alcohol concentration of Campbell's Early and Geubong grapewines fermented with the isolated wild yeast were 80.8%, 11.0% and 87.8%, 13.0%, respectively. Between the isolated wild yeast S. cerevisiae IJ850 and the commercial yeast S. cerevisiae EC1118, total acidities of grapewines produced with wild yeast were lower than those produced with the commercial yeast. The pH values and the values of color analysis of grapewines produced with both strains were similar. The total phenol contents of campbell's Early and Geubong wines produced with the isolated yeast and the commercial yeast were obtained in the range of 75 to 125mg/L. In conclusion, S. cerevesiae IJ850 isolated from the domestic cultured Geubong grape is able to use to produce grapewines as stater culture.

• Microbiology and Biotechnology Letters
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• v.22 no.2
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• pp.152-157
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• 1994

Inulinase of Kluyveromyces marxianus origin was produced by recombinant yeast Saccharomyces cerevisiae under the control of GAL1 promoter, to examine the expression and localization of inulinase in a repressed(galactose-free) or derepressed(galactose-containinga) medium. The inulinase gene(INU1A) was constitutively expressed at 6.7 units/ml in a repressed medium. When the cell started to utilize galactose in a derepressed medium, the INU1A gene began to be expressed, and the final expression level reached about 45 units/ml. According to be the nondenaturingPAGE analysis, inulinase produced by S. cerevisiae was found to be less glycosylated than the bakers yeast invertase. In addition, its glycosylation pattern was less heterogeneous than the K. marxianus inulinase. The supplementation of inulin or raffinose into the derepressed medium increased the cell growth rate, while the expression of INU1A was repressed. Regardless of the carbon sources examined, most of inulinase activity (more than 98%) was found in the extracellular medium, indicating excellent secretion efficiency.

• Journal of Microbiology and Biotechnology
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• v.26 no.5
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• pp.846-853
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• 2016

We displayed four types of Solanum nigrum metallothionein (SMT) for the first time on the surface of Saccharomyces cerevisiae using an α-agglutinin-based display system. The SMT genes were amplified by RT-PCR. The plasmid pYES2 was used to construct the expression vector. Transformed yeast strains were confirmed by PCR amplification and custom sequencing. Surface-expressed metallothioneins were indirectly indicated by the enhanced cadmium sorption capacity. Flame atomic absorption spectrophotometry was used to examine the concentration of Cd²⁺ in this study. The transformed yeast strains showed much higher resistance ability to Cd²⁺ compared with the control. Strikingly, their Cd²⁺ accumulation was almost twice as much as that of the wild-type yeast cells. Furthermore, surface-engineered yeast strains could effectively adsorb ultra-trace cadmium and accumulate Cd²⁺ under a wide range of pH levels, from 3 to 7, without disturbing the Cu²⁺ and Hg²⁺. Four types of surfaceengineered Saccharomyces cerevisiae strains were constructed and they could be used to purify Cd²⁺-contaminated water and adsorb ultra-trace cadmium effectively. The surface-engineered Saccharomyces cerevisiae strains would be useful tools for the bioremediation and biosorption of environmental cadmium contaminants.