• 한국전자현미경학회:학술대회논문집
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• 1999.05a
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• pp.25-25
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• 1999

• Journal of Microbiology and Biotechnology
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• v.32 no.8
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• pp.1047-1053
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• 2022

When ptsG, a glucose-specific phosphotransferase system (PTS) component, is deleted in Escherichia coli, growth can be severely poor because of the lack of efficient glucose transport. We discovered a new PTS transport system that could transport glucose through the growth-coupled experimental evolution of ptsG-deficient E. coli C strain under anaerobic conditions. Genome sequencing revealed mutations in agaR, which encodes a repressor of N-acetylgalactosamine (Aga) PTS expression in evolved progeny strains. RT-qPCR analysis showed that the expression of Aga PTS gene increased because of the loss-of-function of agaR. We confirmed the efficient Aga PTS-mediated glucose uptake by genetic complementation and anaerobic fermentation. We discussed the discovery of new glucose transporter in terms of different genetic backgrounds of E. coli strains, and the relationship between the pattern of mixed-acids fermentation and glucose transport rate.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.1
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• pp.72-80
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• 1997

To elucidate food value and medicinal effect of sea cucumbers, sugar composition of those gly-coprotein and chondroitin sulfate was studied. The contents of sulfate esters in sea cucumbers were 1.21%(blue), 0.90%(red) and 1.19%(black). Predominant carbohydrates were identified as fucose, glucose, D-mannuronic acid and N-acetylglucosamine, and those amount was more than 80% to total carbo-hydrate, while the minor sugar composition was ribose, mannose, galactose, N-acetylgalactosamine and D-glucuronic acid. Also, the major carbohydrate moiety of glycoproteins of sea cucumbers was revealed as fucose, mannose, N-acetylglucosamine, glucose and ribose, and those amount was more than 86% to total carbohydrate. Galactose, N-acetylgalactosamine, D-glucuronic acid and mannuronic acid were minor carbohydrate moiety. The contents of sulfate esters in glycoproteins were 0.96% for blue sea cucumber, 1.15% for red sea cucumber and 1.13% for black sea cucumber, while those in chondroitin sulfates were 3.52%(blue), 3.60%(red) and 3.72%(black). The carbohydrate moiety of chondroitin sulfate was identified as N-acetylgalactosamine (73~ 87%), fucose (7~15%) and D-glucuronic acid(5~12%). As the base on the IR spectrum of strong absorption appeared in 1240$cm^{-1}$ / for stretching vibrations in S=0 group and weak absorptions in 850$cm^{-1}$ / and 820$cm^{-1}$ /for stretching vibrations in C-0-S group, chondroitin sulfates had sulfate group which was bound to $C_4$in fucose.

• 한국전자현미경학회:학술대회논문집
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• 2000.05a
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• pp.33-33
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• 2000

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.11
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• pp.1647-1653
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• 2010

Glycosaminoglycan (GAG) was purified from polysaccharide extracted from sea hare muscle on DEAE-Sepharose column and investigated for the functional groups, distribution of sugars, composition of disaccharide and structure of GAG. Purified GAG was composed of disaccharide above 55% of total sugar. Purified GAG showed amide I peak in 1648/cm and C-O stretch peak as properties of carbohydrate, amino acid peak in 1457/cm, and peak in 866/cm as properties of monosaccharide by FT-IR. Fucose, N-acetylgalactosamine, N-acetylglucosamine, glucose, galactose, mannose and xylose were found in MALDI-TOF MS/MS spectra of hydrolysates by chondroitin sulfate ABC lyase and heparanase I. Purified GAG was expected to be heparan sulfate including N-acetylgalactosamine and N-acetylglucosamine above 70% of total sugar. The structure of GAG was supposed as GlyUA(2S)-GlcNS and GlyUA-GlcNS(6S) with O-linkage on protein core.

• Applied Microscopy
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• v.31 no.1
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• pp.49-57
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• 2001

In this study, the distribution of lectin receptors in culutured fibroblast was explored using colloidal gold label complexed with lectin WGA purified from wheat germ (Triticum vulgare). The lectin WGA gold complex, shown to recognize GlcNAc (N-acetylgalactosamine) and NeuNAc (N-acetylneuraminic acid) regions, was applied to detect binding sites in Lowicryl HM 20 sections viewed under electron microscope Labeled sections of the culutured fibroblast revealed gold particles specifically distributed on the cytoplasm and cell surface of the fibroblast. Labeling of 24 hours culutured fibroblast was then quantified and compared to that of 72 hours culutured fibroblast. 24 hours culutured fibroblast sections resulted in specific gold particle distribution on the cytoplasmic vesicle of the culutured fibroblast. These results indicate that lectin WGA receptors are located in the cytoplasmic vesicle and cell surface of the 24 hours culutured fibroblast, and on the cell surface of the 72 hours culutured fibroblast. Therefore, the GlcNAc and NeuNAc regions on the cell surface appear to be functionally associated with cell-recognition and protection from other cell of the tissue, and linked with secretion and exocytosis of the fibroblast cytoplasm.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2001.11a
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• pp.69-70
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• 2001

Lectins have great potential as to determine the alternation of the distribution of cell surface carbohydrates during cellular development and differentiation. Here, we investigated the presence and distribution of cell surface carbohydrates on chicken primordial germ cells (PGCs) during the migration and gonadal stages using a variety of lectins. A total of six FITC-labelled lectins from several specificity classes were used: ConA (glucose/mannose), WGA (N-acetylglucosamine), STA (N-acetylglucosamine), DBA (N-acetylgalactosamine/galactose), UEA-I (fucose) and PHA-E (oilgosaccharide). As a results, PGC-specific binding was observed in STA. PGCs of migration stage (2.5- and 5.5-day embyos) were STA-positive whereas PGCs of 10-day embryonic gonad were not. The results suggest that N-acetylglucosamine residuse are present specifically in migrating chicken PGCs and changes during development.

• BMB Reports
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• v.29 no.3
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• pp.266-271
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• 1996

A recombinant human erythropoietin (EPO), expressed in Chinese hamster ovary (CHO) cells, is glycosylated at Asn 24, Asn 38, Asn 83, and Ser 126. After release of the N-linked carbohydrate chains by $peptide-N^{4}-(N-acetyl-{\beta}-glucosaminyl)$ asparagine amidase F, the oligosaccharides were analyzed by FACE (Fluorophore-Assisted Carbohydrate Electrophoresis). The O-linked carbohydrate chain was separated by hydrazine, and analyzed by FACE. The monosacccharide composition of recombinant EPO showed man nose, fucose, galactose, N-acetylglucosamine, N-acetylneuraminic acid, and a trace of N-acetylgalactosamine, which are typical monosaccharides in the glycoproteins from the CHO cell. Sequences of N-linked and O-linked oligosaccharides were determined. The structure and composition of oligosaccharides attached to recombinant human EPO, expressed in the CHO cell, are identical to the reported oligosaccharide structure in human EPO isolated from urine.

• Applied Microscopy
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• v.30 no.1
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• pp.101-111
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• 2000

In this study, the distribution of lectin receptors in Paragonimus westermani tissue was explored using colloidal gold label complexed with lectin WGA purified from wheat germ (Triticum vulgare). The lectin WGA gold complex, shown to recognize GlcNAc (N-acetylgalactosamine) and NeuNAc (N-acetylneuraminic acid) regions, was applied to detect binding sites in Lowicryl HM 20 sections viewed under electron microscope. Labeled sections of the metacercaria revealed gold particles specifically distributed on the tegumental syncytium and lamella of the excretory canal. Labeling of young adult tissue was then quantified and compared to that of adult worm tissue. Adult worm tissue sections resulted in specific gold particle distribution on the lamella of caecal epithelium and excretory canal. These results indicate that lectin WGA receptors are located in the tegumental syncytium and lamella of the excretory canal of the metacercariae, and in the lamella of the caecum and excretory canal of the young adult and adult. Therefore, the GlcNAc and NeuNAc regions in the tegumental syncytium appear to be functionally associated with cell-recognition and protection from the immune system of the host, and linked with membrane transport and absorption of nutrients in the lamella of the excretaory canal and caecal epithelia.

• Journal of Microbiology and Biotechnology
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• v.30 no.7
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• pp.1092-1096
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• 2020

YjiC, a glycosyltransferase from Bacillus licheniformis, is a well-known versatile enzyme for glycosylation of diverse substrates. Although a number of O-glycosylated products have been produced using YjiC, no report has been updated for nucleophilic N-, S-, and C- glycosylation. Here, we report the additional functional capacity of YjiC for nucleophilic N- and S- glycosylation using a broad substrate spectrum including UDP-α-D-glucose, UDP-N-acetyl glucosamine, UDP-N-acetylgalactosamine, UDP-α-D-glucuronic acid, TDP-α-L-rhamnose, TDP-α-D-viosamine, and GDP-α-L-fucose as donor and various amine and thiol groups containing natural products as acceptor substrates. The results revealed YjiC as a promiscuous enzyme for conjugating diverse sugars at amine and thiol functional groups of small molecules applicable for generating glycofunctionalized chemical diversity libraries. The glycosylated products were analyzed using HPLC and LC/MS and compared with previous reports.