• Journal of Microbiology and Biotechnology
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• v.22 no.11
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• pp.1486-1493
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• 2012

In this study, we investigated whether galactooligosaccharide (GOS) can be stably and steadily synthesized using immobilized ${\beta}$-galactosidase (${\beta}$-gal) inclusion body (IB)-containing E. coli cells during long-term repeated-batch operation. To improve the operational stability of this enzyme reactor system, immobilized E. coli cells were crosslinked with glutaraldehyde (GA) after immobilization of the E. coli. When we treated with 2% GA for E. coli crosslinking, GOS production continued to an elapsed time of 576 h, in which seven batch runs were operated consecutively. GOS production ranged from 51.6 to 78.5 g/l ($71.2{\pm}10.5$ g/l, n = 7) during those batch operations. In contrast, when we crosslinked E. coli with 4% GA, GOS production ranged from 31.5 to 64.0 g/l ($52.3{\pm}10.8$, n = 4), and only four consecutive batch runs were operated. Although we did not use an industrial ${\beta}$-gal for GOS production, in which a thermophile is used routinely, this represents the longest operation time for GOS production using E. coli ${\beta}$-gal. Improved stability and durability of the cell immobilization system were achieved using the crosslinking protocol. This strategy could be directly applied to other microbial enzyme reactor systems using cell immobilization to extend the operation time and/or improve the reactor system stability.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2447-2451
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• 2013

Objective: To study changes of tumor associated carbohydrate antigen (TACAs) expression and mRNA levels for tumor associated glycosyltransferases, and assess subcellular localizations of N-acetyl galactosyltransferases (GalNAc-Ts) in the K562 leukemia cell line after imatinib treatment. Methods: RT-PCR was performed to analyze the expression of glycosyltransferases which synthesize O-glycan in tumor-associated carbohydrate antigens (TCTAs). The expression of Tn antigen, T antigen and sialyl T antigen on K562 cell membranes was measured by flow cytometry after treatment with different concentrations of imatinib. Co-localization of GalNAc-Ts and ER (endoplasmic reticulum) was determined by confocal laser scanning microcopy. Results: Transcript expression levels of several glycosyltransferases related to TCTAs were decreased after imatinib ($0-0.3{\mu}M$) treatment. Expression of Tn antigen and T antigen was increased while that of sialyl T antigen was decreased. Co-localization of GalNAc-Ts and ER was reduced by $0.2{\mu}M$ of imatinib. Conclusion: Imatinib inhibited the expression of O-glycan related TACAs and several related glycosyltransferases, while decreasing the co-localization of GalNAc-Ts and ER and normalizing O-glycosylation in the K562 human leukemia cell.

• Journal of Microbiology and Biotechnology
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• v.17 no.9
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• pp.1469-1476
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• 2007

Jeot-gal is a traditional Korean fermented seafood and has long been used for seasoning. We isolated 188 strains from shrimp, anchovy, and yellow corvina Jeot-gal, and screened sixteen strains that showed strong fibrinolytic activities on a fibrin plate. Among those strains, the strain that had the largest halo zone was chosen and identified as Bacillus licheniformis by using 16S rDNA sequencing and an API CHB kit. The fibrinolytic activity of Bacillus licheniformis was characterized and designated as bpKJ-31. The active component of bpKJ-31 was identified as a 37 kDa protein, designated bacillopeptidase F, by internal peptide mapping and N-terminal sequencing. The optimum activity of bpKJ-31 was shown at pH 9 and $40^{\circ}C$, with a chromogenic substrate for plasmin. It had high degrading activity for the $B{\beta}$-chain and $A{\alpha}$-chain of fibrin(ogen), and also acted on thrombin, but not skim milk and casein. The amidolytic activity of bpKJ-31 was inhibited by 1 mM phenylmethanesulfonyl fluoride, but 1 mM EDTA did not affect the enzyme activity, indicating that bpKJ-31 is an alkaline serine protease, like a plasmin. The bpKJ-31 showed approximately 14.3% higher fibrinolytic activity than the plasmin. These features of bpKJ-31 make it attractive as a health-promoting biomaterial.

• Proceedings of the Korean Society of Life Science Conference
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• 2003.05a
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• pp.77-77
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• 2003

• Journal of the Korean Mathematical Society
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• v.38 no.3
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• pp.623-631
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• 2001

Let $\kappa$ be a real abelian field of conductor f and $\kappa$(sub)$\infty$ = ∪(sub)n$\geq$0$\kappa$(sub)n be its Z(sub)p-extension for an odd prime p such that płf$\phi$(f). he aim of this paper is ot compute the cohomology groups of circular units. For m>n$\geq$0, let G(sub)m,n be the Galois group Gal($\kappa$(sub)m/$\kappa$(sub)n) and C(sub)m be the group of circular units of $\kappa$(sub)m. Let l be the number of prime ideals of $\kappa$ above p. Then, for mm>n$\geq$0, we have (1) C(sub)m(sup)G(sub)m,n = C(sub)n, (2) H(sup)i(G(sub)m,n, C(sub)m) = (Z/p(sup)m-n Z)(sup)l-1 if i is even, (3) H(sup)i(G(sub)m,n, C(sub)m) = (Z/P(sup)m-n Z)(sup l) if i is odd (※Equations, See Full-text).

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.213.2-214
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• 2003

Three mistletoe lectins (ML -I, ML -IIU, ML -IIL) have been identified in Europe based on sugar specificities for galactose(Gal) and N-acetyl galactosamine(GalNAc). Korean mistletoe lectins have been known as mainly ML -II type. In previous results, we suggested that there are two lectins, 64 KDa and 60 KDa, in Korean mistletoe lectin (KML -C). (omitted)

• Journal of Microbiology and Biotechnology
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• v.14 no.4
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• pp.751-758
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• 2004

The NCS(Non-Cariogenicity Sugar) from Bacillus sp. S-1013 was purified by cold acetone and methanol precipitation, and DEAE-cellulose ion-exchange and Sephadex G-100 column chromatographies, to yield an amorphous yellow syrup. The melting point and $[\alpha]_D^{20}$ were 155-$157^{\circ}C$ and +53, respectively. Instrumental analyses such as FT-IR, $^1H-NMR, and ^{13}C-NMR$ showed that the NCS contained an O-H group, C-H, C=O, $NH_2$, anomeric carbon, anomeric proton, N-acetylgalactose, fucose, and neuramic acid, thus, the NCS was determined to be a trisaccharide of Fuc($1\longrightarrow4$)GalNAc($2\longrightarrow6$) NeuAc.

• BMB Reports
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• v.50 no.5
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• pp.233-234
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• 2017

Aberrant expression of the polypeptide N-acetyl-galactosaminyltransferase (GALNTs) has been associated with cancer, but their function(s) in metastasis remains elusive. We have recently identified GALNT14, one of the O-GalNAc glycosylation-initiating enzymes, as a prognostic marker for pulmonary relapse in breast cancer patients. Furthermore, we showed that GALNT14 promotes lung metastasis by the following novel mechanisms: 1) enhancing metastasis initiation by inhibiting the anti-metastatic effect of BMP produced from the lung stroma, 2) exploiting growth signals (e.g. FGF) supplied by macrophages, for their growth into macrometastases in the lung environment. These multi-faceted roles of GALNT14 in lung metastasis are achieved by GALNT14-mediated inhibition and activation of the BMP and FGF signaling pathways, respectively. The link among GALNT14, its downstream pathways and lung metastasis, provides us with an opportunity to develop effective therapeutic intervention for breast cancer.

• Korean Journal of Food Science and Technology
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• v.49 no.6
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• pp.676-684
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• 2017

The present study aimed to examine the hepatoprotective effects of ethanol extracts from steam-dried ginseng berry (SGBE) in both $\text\tiny{D}$-Galactosamine/Lipopolysaccharide ($\text\tiny{D}$-GalN/LPS)-sensitized mice and in vitro models. Our results clearly demonstrated that SGBE significantly reduced the level of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and lactate dehydrogenase in blood, and $TNF{\alpha}$ was normalized in 8 h after the treatment with $\text\tiny{D}$-GalN/LPS. Coincidently, major organs remained unimpaired when compared to $\text\tiny{D}$-GalN/LPS control group. Moreover, p38, which stimulates expression of NAFLD-associated cytokines, was markedly inhibited when treated with SGBE. In vitro analysis revealed that the main components of SGBE, linoleic acid and ginsenoside Re/Rd, may play a role in protecting liver from $\text\tiny{D}$-GalN/LPS-induced toxicity. Finally, we concluded that SGBE may be a promising therapeutic agent for preventing damage to the liver.

• Journal of Life Science
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• v.17 no.9 s.89
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• pp.1248-1254
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• 2007

The secretory overexpression of Clostridium thermocellum endoglucanase A gene (celA) was examined in Saccharomyces cerevisiae using Kluyveromyces marxianus exoinulinase (INU1) signal sequence and GAL10 promoter. The two plasmids, pYEG-CT1 with its own signal sequence, and pYInu-CT1 with INU1 signal sequence were introduced to S. cerevisiae SEY2102 and S. cerevisiae 2805 host strains, respectively, and then each transformant was selected on the synthetic defined media lacking uracil. The expression level and secretion efficiency of endoglucanase A was increased by $18{\sim}22%$ and 11%, respectively, by INU1 signal sequence over celA signal sequence. By considering the high level of expression (361 unit/I), plasmid stability (89%), and secretion efficiency (70%), S. cerevisiae 2805 harboring plasmid pYInu-CT1 was selected as the opti-mal host vector system for the production of cellulose-degrading enzyme and recombinant yeast probiotic. The total expression and secretion efficiency of endoglucanase A was 418 unit/l and 73%, respectively, in the batch fermentation of S. cerevisiae 2805/pYlnu-CT1 on galactose medium. The mo-lecular weight of secreted endoglucanase A was found to be greater than 100 kDa, presumably due to the N-linked glycosylation.