• Biotechnology and Bioprocess Engineering:BBE
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• v.3 no.1
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• pp.40-43
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• 1998

The glycosylation pattern of Erythropoietin (EPO), produced by recombinant CHO cells, was studied using the simple and rapid technique of 'Lectin-blotting'. In this experiment we used three different kinds of lectins, MAA(Maackia amurensis agglutinine), RCA(Ricinus communis agglutinine), and DSA(Datura stramonium agglutinine), which bind to the terminal sialic acid, galactose, and the N-acetyllactosamine chain respectively. The lectin-blotting technique was used to analyze the carbohydrate structure of EPO produced in the presence of two physiologically active chemical compounds, ammonium and chloroquine. The effect of the ammonium ion on the glycosylation of EPO was studied because it accumulated in the medium mainly as a by-product of glutamine matabolism. Ammonium chloride significantly inhibited the sialylation of the terminal galactose residue at concentrations of 8mM or more. Chloroquine, a potent inhibitor of glycosylation, inhibited terminal sialylation at concentrations of 100 and 200 $\mu$M, and at a concentration of 300 $\mu$M, also inhibited Nacetyllactosamine chain synthesis.

• Bulletin of the Korean Chemical Society
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• v.25 no.1
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• pp.63-68
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• 2004

Sugar-based gelator p-dodecanoyl-aminophenyl- ${\beta}$-D-aldopyranosides (1-3) have been shown to self-assemble in the presence of p-aminophenyl aldopyranosides. The hydrogel 1+4 showed the double-helical structure with 3-25 nm outer diameters, which is quite different from that of 1. The gel 2+5 revealed twisted ribbon structure with 30-50 nm in widths and a few micrometers of length whereas the gel 3+4 revealed the single and the bundled fiber structures. The difference in these gel supramolecular structures has successfully been transcribed into silica structures by sol-gel polymerization of tetraethoxysilane (TEOS), resulting in the doublehelical, the twisted-ribbon, the single and the multiple (lotus-shaped) hollow fiber structures. These results indicate that novel silica structures can be created by transcription of various superstructures formed in binary gels through the hydrogen-bonding interaction, and the amino group of the p-aminophenyl aldopyranosides acts as an efficient driving force to create novel silica nanotubes. Furthermore, electron energy-loss spectroscopy (ELLS) provided strong evidence for the inner hollow structure of the double-helical silica nanotube. This is a novel and successful example that a variety of new silica structures can be created using a library of carbohydrate gel fibers as their templates.

• Molecules and Cells
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• v.39 no.6
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• pp.495-500
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• 2016

We have solved the crystal structure of a predicted fructose-specific enzyme $IIB^{fruc}$ from Escherichia coli ($EcEIIB^{fruc}$) involved in the phosphoenolpyruvate-carbohydrate phosphotransferase system transferring carbohydrates across the cytoplasmic membrane. $EcEIIB^{fruc}$ belongs to a sequence family with more than 5,000 sequence homologues with 25-99% amino-acid sequence identity. It reveals a conventional Rossmann-like ${\alpha}-{\beta}-{\alpha}$ sandwich fold with a unique ${\beta}$-sheet topology. Its C-terminus is longer than its closest relatives and forms an additional ${\beta}$-strand whereas the shorter C-terminus is random coil in the relatives. Interestingly, its core structure is similar to that of enzyme $IIB^{cellobiose}$ from E. coli ($EcIIB^{cel}$) transferring a phosphate moiety. In the active site of the closest $EcEIIB^{fruc}$ homologues, a unique motif CXXGXAHT comprising a P-loop like architecture including a histidine residue is found. The conserved cysteine on this loop may be deprotonated to act as a nucleophile similar to that of $EcIIB^{cel}$. The conserved histidine residue is presumed to bind the negatively charged phosphate. Therefore, we propose that the catalytic mechanism of $EcEIIB^{fruc}$ is similar to that of $EcIIB^{cel}$ transferring phosphoryl moiety to a specific carbohydrate.

• Journal of Ginseng Research
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• v.31 no.2
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• pp.69-73
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• 2007

Since chemical structures of ginsenoside as active ingredient of Panax ginseng are known, accumulating evidence have shown that ginsenoside is one of bio-active ligands through the diverse physiological and pharmacological evaluations. Chemical structures of ginsenoside could be divided into three parts depending on diol or triol ginsenoside: Steroid- or cholesterol-like backbone structure, carbohydrate portions, which are attached at the carbon-3, -6 or -20, and aliphatic side chain coupled to the backbone structure at the carbon-20. Ginsenosides also exist as stereoisomer at the carbon-20. Bioactive ligands usually exhibit the their structure-function relationships. In ginsenosides, there is little known about the relationship of chemical structure and biological activity. Recent reports have shown that ginsenoside $Rg_3$, one of active ginsenosides, exhibits its differential physiological or pharmacological actions depending on its chemical structure. This review will show how ginsenoside $Rg_3$, as a model compound, is functionally coupled to voltage-gated ion channel or ligand-gated ion channel regulations in related with its chemical structure.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.4
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• pp.421-428
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• 2007

Eight varieties of milled rice showing different palatabilities were studied in order to identify the relationship between physicochemical properties of carbohydrate components and their fine structure. Gopumbyeo showed the highest palatability value among the eight varieties tested. Both peak viscosity and breakdown were hightest in Hitomebore, and lowest in Mihyangbyeo. No relationship was indicated between the palatability and gelatinization properties. The amylose content of starch showed a significant difference among the varieties tested. However, no relationship was found between the structure of amylose and the palatability of milled rice. The degree of branching(B/A value) was highest in Saechucheongbyeo, and lowest in Palgongbyeo in fine structure of amylopectin. But no relationship was indicated between the B/A values and the palatability of milled rice. Difference was indicated in properties of gelatinization of starch by differential scanning calorimetry. The enthalphy for gelatinization showed a significant difference among the varieties. However, no relationship was found between the enthalphy for gelatinization and the palatability of milled rice. Monosaccharide in endosperm was composed of rice were compound of rhamnose, fucose, ribose, arabinose, and xylose. The total content of monosaccharides was highest in Saechucheongbyeo, and lowest in Palgongbyeo. However, 7 varieties of milled rice, expect Palgongbyeo, showed no relationship between the palatability and monosaccharides contents.

• Journal of Microbiology and Biotechnology
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• v.15 no.2
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• pp.395-402
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• 2005

Biologically active recombinant human follicle stimulating hormone (rhFSH) was produced in Chinese hamster ovary cells and purified by a series of chromatographic steps. The chromatographic steps included anion-exchange chromatography (DEAE Sepharose F/F, Q Sepharose F/F), hydrophobic interaction chromatography (Source 15 PHE), and hydroxyapatite chromatography (Macro-Prep ceramic hydroxyapatite type I). A distinctive step of the purification process developed was the use of ZnCl$_2$ for the removal of non-glycosylated or lowly-glycosylated FSH and impurities through co-precipitation with Zn$^{2+}$. Purified rhFSH was identified and characterized by several physicochemical and biological methods such as gel electrophoresis, high-performance liquid chromatography, amino acid analysis, carbohydrate analysis, and biological activity. The overall yield of the purification was ~$30\%$. The rhFSH preparation obtained showed high purity (>$99\%$) and high in vivo potency (>16,000 IU/mg). Carbohydrate analysis suggested that the purified rhFSH contained approximately $40\%$ (w/w) carbohydrate with di­or tri-antennary structure on average, which is somewhat more heavily sialylated than commercially available rhFSH. In conclusion, the results of these analyses established an identity of the purified rhFSH with natural FSH from human pituitary glands, and furthermore, the purified rhFSH preparation showed higher in vivo potency and was slightly more heavily sialylated than commercially available rhFSH.

• Archives of Pharmacal Research
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• v.22 no.3
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• pp.243-248
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• 1999

Sialic acids are key determinants for biological processes, such as cell-cell interaction and differentiation. Sialyltransferases contribute to the diversity in carbohydrate structure through their attachment of sialic acid in various terminal positions on glycolipid and glycoprotein (N-linked and O-linked) carbohydrate groups. Gal$\beta$ 1,3(4)GlcNAc $\alpha$2,3-sialyltransferase (ST3Gal III) is involved in the biosynthesis of $sLe^{X}$ and sLe^{a}$ known as selection ligands and tumor-associated carbohydrate structures. The appearance and differential distribution of ST3Gal III mRNA during mice embryogenesis [embryonic (E) days; E9, E11, E13, E15] were investigated by in situ hybridization with digoxigenin-labeled RNA probes coupled with alkaline phosphatase detection. On E9, all tissues were positive for ST3Gal III mRNA expression whereas ST3Gal III mRNA on E11 was not detected throughout all tissues. On E13, ST3GAl III mRNA was expressed in different manner in various tissues. In this stage, ST3Gal III mRNA was positive only in the liver, pancreas and bladder. On E15, specific signal for ST3GAl III was detected in the liver, lung and forebrain. These results indicate that ST3Gal III is differently expressed at developmental stages of mice embryo, and this may be importantly related with regulation of organogenesis in mice.

• Journal of fish pathology
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• v.25 no.1
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• pp.11-20
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• 2012

C-type lectins are crucial for pathogen recognition, innate immunity, and cell-cell interactions. In this study, a C-type lectin gene was cloned from the rock bream. The full-length RbCTL cDNA was 729 bp with a 429 bp ORF encoding a 164-residue protein. The deduced amino acid sequence of RbCTL had all of the conserved features crucial for its fundamental structure, including the four cysteine residues involved in sulfide bridge formation and potential $Ca^2+$/carbohydrate-binding sites. RbCTL contains a signal peptide one single carbohydrate recognition domain. It showed 29.4% similarity to the C-type lectin of rainbow trout. RbCTL mRNA was predominately expressed in gill and head-kidney tissue and expressed less in peripheral blood leukocytes, trunk-kidney, spleen, liver, intestine and muscle. Expression of RbCTL was differentially upregulated in rock bream stimulated with LPS, Con A/PMA and poly I:C.

• Mycobiology
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• v.48 no.2
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• pp.104-114
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• 2020

The carbohydrate-active enzyme (CAZyme) genes of Trametes contribute to polysaccharide degradation. However, the comprehensive analysis of the composition of CAZymes and the biosynthetic gene clusters (BGCs) of Trametes remain unclear. Here, we conducted comparative analysis, detected the CAZyme genes, and predicted the BGCs for nine Trametes strains. Among the 82,053 homologous clusters obtained for Trametes, we identified 8518 core genes, 60,441 accessory genes, and 13,094 specific genes. A large proportion of CAZyme genes were cataloged into glycoside hydrolases, glycosyltransferases, and carbohydrate esterases. The predicted BGCs of Trametes were divided into six strategies, and the nine Trametes strains harbored 47.78 BGCs on average. Our study revealed that Trametes exhibits an open pan-genome structure. These findings provide insights into the genetic diversity and explored the synthetic biology of secondary metabolite production for Trametes.

• Journal of Microbiology and Biotechnology
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• v.18 no.8
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• pp.1459-1469
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• 2008

Using a rotating biological contactor modified with a sequencing bath reactor system (SBRBC) designed and operated to remove phosphate and nitrogen [58], the microbial community structure of the biofilm from the SBRBC system was characterized based on the extracellular polymeric substance (EPS) constituents, electron microscopy, and molecular techniques. Protein and carbohydrate were identified as the major EPS constituents at three different biofilm thicknesses, where the amount of EPS and bacterial cell number were highest in the initial thickness of 0-100${\mu}m$. However, the percent of carbohydrate in the total amount of EPS decreased by about 11.23%, whereas the percent of protein increased by about 11.15% as the biofilm grew. Thus, an abundant quantity of EPS and cell mass, as well as a specific quality of EPS were apparently needed to attach to the substratum in the first step of the biofilm growth. A FISH analysis revealed that the dominant phylogenetic group was $\beta$- and $\gamma$-Proteobacteria, where a significant subclass of Proteobacteria for removing phosphate and/or nitrate was found within a biofilm thickness of 0-250${\mu}m$. In addition, 16S rDNA clone libraries revealed that Klebsiella sp. and Citrobacter sp. were most dominant within the initial biofilm thickness of 0-250${\mu}m$, whereas sulfur-oxidizing bacteria, such as Beggiatoa sp. and Thiothrix sp., were detected in a biofilm thickness over 250${\mu}m$. The results of the bacterial community structure analysis using molecular techniques agreed with the results of the morphological structure based on scanning electron microscopy. Therefore, the overall results indicated that coliform bacteria participated in the nitrate and phosphorus removal when using the SBRBC system. Moreover, the structure of the biofilm was also found to be related to the EPS constituents, as well as the nitrogen and phosphate removal efficiency. Consequently, since this is the first identification of the bacterial community and structure of the biofilm from an RBC simultaneously removing nitrogen and phosphate from domestic wastewater, and it is hoped that the present results may provide a foundation for understanding nitrate and phosphate removal by an RBC system.