• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2004.06a
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• pp.278-281
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• 2004

The $\alpha$1,6-mannosyltransferase encoded by Saccharomyces cerevisiae OCH1 plays a key role for the outer chain initiation of the N-linked oligosaccharides. A search for Hansenula polymorpha genes homologous to S. cerevisiae OCHI (ScOCH1) has revealed seven open reading frames (ORF100, ORF142, ORF168, ORF288, ORF379, ORF576, ORF580). All of the seven ORFs are predicted to be a type II integral membrane protein containing a transmembrane domain near the amino-terminal region and has a DXD motif, which has been found in the active site of many glycosyltransferases. Among this seven-membered OCH1 gene family of H. polymorpha, we have carried out a functional analysis of H. polymorpha ORF168 (HpOCH2) showing the highest identity to ScOCH1. Inactivation of this protein by disruption of corresponding gene resulted in several phenotypes suggestive of cell wall defects, including hypersensitivity to hygromycin B and sodium deoxycholate. The structural analysis of N-glycans synthesized in HpOCH2-disrupted strain (Hpoch2Δ) and the in vitro $\alpha$1,6-mannosyltransferase activity assay strongly indicate that HpOch2p is a key enzyme adding the first $\alpha$1,6-mannose residue on the core glycan Man$_{8}$GlcNAc$_2$. The Hpoch2Δ was further genetically engineered to synthesize a recombinant glycoprotein with the human compatible N-linked oligosaccharide, Man$_{5}$GlcNAc$_2$, by overexpression of the Aspergillus saitoi $\alpha$1,2-mannosidase with the 'HDEL” ER retention signal.gnal.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.1
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• pp.20-24
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• 2000

A 7-week growth trial was conducted to investigate the effects of yeasts (Kluyveromyces fragilis and Candida utilis) with or without cell wall chemical treatment (protoplasted) in formulated diets on growth and body composition of larval ayu (Plecoglossus altivelis). Three replicate groups of ap average weighing 100 mg were fed diets containing each level ($5{\%}$) of K. fragilis, protoplasted K. fragilis, C. utilis, protoplasted C. utilis or brewer's yeast as an additive. Survival rate of fish fed the diet containing protoplasted K. fragilis, C. utilis or protoplasted C. utilis was higher than that of fish tea the control diet (P<0.05). Body weight .gain of fish fed the diet containing protoplasted K. fragilis was higher than that of fish fed the control diet (P<0.05). Crude protein and ash contents of Ssh were not significantly affected by the different dietary yeasts (P>0.05), On the other hand, crude lipid content of fish fed the diet containing K. fragilis, protoplasted K. fragilis or brewer's yeast was higher than that of fish fed the control diet (P<0.05). Amino acids composition of fish was not significantly affected by the different dietary yeasts (P>0.05), except aspartic acid. The results suggest that protoplasted K. fragilis as an additive in micro-formulated diet can improve weight gain and body quality of larval ayu.

• Korean Journal of Food Science and Technology
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• v.12 no.4
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• pp.254-262
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• 1980

A series of experiment were carried out to separate the factor accelerating the lysis of cell wall of $Saccharomyces\;sak{\acute{e}}$ from the preparation of crude zymolyase obtained from Arthrobacter luteus. An attempt was also made to purify the enzyme which is essential for the study on the separation of the factor. The results are summarized as follows: 1. Crude zymolyase was fractionated 5 peaks $(A{\sim}E)$ containing three peaks $(A{\sim}C)$ passed through the column by the chromatography on Biogel CM-30. 2. Among the five peaks, peak E (protease fraction) was found to contain the factor accelerating the lytic activity of the zymolyase. 3. L-c fraction purified in almost free form from the nonlytic ${\beta}-1$, 3-glucanase, protease and inert protein by the affinity adsorption chromatography with Sephadex G-75 gel was obtained from zymolyase fraction (peak D). When it was subjected to polyacrylamide gel disc electrophoresis, only one clear protein band was observed at pH 4. 5, but still detected two or more band at pH 8. 3.

• Korean Journal of Oriental Medicine
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• v.15 no.3
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• pp.83-91
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• 2009

$\beta$-glucan is a fiber-type complex sugar (polysaccharide) derived from the cell wall of baker's yeast, oat and barley fiber, and many medicinal mushrooms, such as maitake. The primary uses of $\beta$-glucan are to enhance the immune system, to lower blood cholesterol levels and to treat tumor. $\beta$-glucan has no systemic toxicity in mice, therefore it needed clinical trail to prove efficacy and safety for human. The subjects total 56 healty volunteers were divided into two groups including taken $\beta$-glucan tablet group and placebo group. Subjects were taken two tablets per oral for 4 weeks. They had agreed to take part in this experiment, and didn't take any other clinical trail products. After 4 weeks blood of subjects were checked. The check list are TNF-$\alpha$, INF-$\gamma$, IL-2, IL-4, total WBC, differential WBC, RBC, hemoglobin, platelet, MCV, MCH, MCHC, HCT, Na, K, Ca, Cl, AST, ALT, ALP, $\gamma$-GTP, total protein, triglyceride, total cholesterol, total bilirubin, albumin, uric acid, creatinine, BUN, pH, protein, glucose, ketone body, blood, bilirubin. We evaluated efficacy by cytokines that compare before and after taking. Collected data were analyzed as two sample t-test, chi-square test and ANOVA using SAS V.9.1.This study results are that in TNF-$\alpha$ of $1^{st}$ efficacy measurement item, all of two groups figure were increased significantly compare to before figure. In IL4 of $2^{nd}$ efficacy measurement item, experimental group figure were decreased significantly but placebo group figure were increased. The conclusions show that based on the above results, $\beta$-glucan has favorable effect to enhance immune system, especially IL4 results showed that it has effect to improve the allergic immune system.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.6
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• pp.791-797
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• 1999

This study was conducted in order to evaluate nutritive values of yeasts (Kluyveromyces fragilis and Candida utilis) according to growth stages (early log phase, log phase, stationary phase and death phase) and chemical treatment of their cell wall, Proximate, amino acids, fatty acids and nucleotides composition of the yeast samples was determined. Crude protein content was high in K. fragilis ($48\~59\%$) compared to C. utilis ($26\~43\%$). Crude lipid and fiber contents of the yeasts were below than $1.6\%$ and $3.3\%$, respectively. Conposition of aspartic acid, glycine, proline, leucine, Iysine and valine of K. fragilis were higher than those of C. utilis, and glutamic acid and arginine of C. utilis were higher than those of K. fragilis. Proximate and amino acids composition was not siginificantly influenced by growth stage of the yeasts. Major fatty acids of the yeasts in all growth stages were $C_{10-18}$. $C_{16-18}$ contents were relatively high in the early log or log phase and $C_{10-12}$ contents were relatively high in the stationary or death phase. However, n-3 highly unasturated fatty acids (C$\ge$20) in the all growth stages were not observed. This result indicated that these yeast strains could not be adequate as a dietary lipid source for marine fish. Composition of nucleotides and their related compounds (ATP ADP AMP, IMP and inosine) in the early log phase yeasts were lower than those in the log, stationary and death phase yeasts.

• Journal of Life Science
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• v.27 no.11
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• pp.1256-1261
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• 2017

${\beta}$-glucan is a constituent of the cell wall of fungi, yeast and plants. It plays an important role in the immune system such as activation of immunocyte, release of pro-inflammatory and anti-cancer effect. The immune system maintains a healthy immune homeostasis. However, when pathogenic substances enter the body, immune homeostasis can break down and disease can be triggered. Therefore, we studied a substance that regulates immune homeostasis. The purpose of the study we demonstrated whether the ${\beta}$-glucan can be applied to the immune-modulation effects in human monocytic THP-1 cells. ${\beta}$-glucan was incubated in THP-1 cells at various concentrations. The $TNF-{\alpha}$ mRNA expression and protein levels were analyzed by ELISA and Real-time PCR. Additionally, the expression of MAPKs (p38 and JNK), $I{\kappa}B-{\alpha}$ and $NF-{\kappa}B$ p50 were analyzed by western blot. ${\beta}$-glucan enhanced the production of $TNF-{\alpha}$ mRNA expression and protein levels in human monocytic THP-1 cells. In addition, activation of MAPKs (p38 and JNK) and $NF-{\kappa}B$ p50 induced by ${\beta}$-glucan were increased. The study suggests that ${\beta}$-glucan contributes to immune-stimulation effect by production $TNF-{\alpha}$ in human monocytic THP-1 cells, and that MAPKs and $NF-{\kappa}B$ p50 are involved in the process. Synthetically, we have suggested ${\beta}$-glucan may be improved to immune system effect in human monocytic THP-1 cells.