• BMB Reports
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• v.35 no.3
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• pp.330-336
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• 2002

The lgtB genes that encode $\beta$-1,4-galactosyltransferases from Neisseria meningitidis ATCC 13102 and gonorrhoeae ATCC 31151 were isolated by a polymerase chain reaction using the pfu DNA polymerase. They were expressed under the control of lac and T7 promoters in Escherichia coli M15 and BL21 (DE3). Although the genes were efficiently expressed in E. coli M15 at $37^{\circ}C$ (33 kDa), most of the $\beta$-1,4-galactosyltransferases that were produced were insoluble and proteolysed into enzymatically inactive polypeptides that lacked C-terminal residues (29.5 kDa and 28 kDa) during the purification steps. When the temperature of the cell growth was lowered to $25^{\circ}C$, however, the solubility of the $\beta$-1,4-galactosyltransferases increased substantially. A stable N-terminal his-tagged recombinant enzyme preparation could be achieved with E. coli BL21 (DE3) that expressed lgtB. Therefore, the cloned $\beta$-1,4-galactosyltransferases were expressed under the control of the T7 promoter in E. coli BL21 (DE3), mostly to the soluble form at $25^{\circ}C$. The proteins were easily purified to homogeneity by column chromatography using Ni-NTA resin, and were found to be active. The galactosyltransferases exhibited pH optimum at 6.5-7.0, and had an essential requirement for the $Mn^{+2}$ ions for its action. The $Mg^{+2}$ and $Ca{+2}$ ions showed about half of the galactosyltransferase activities with the $Mn^{+2}$ ion. In the presence of the $Fe^{+2}$ ion, partial activation was observed with the $\beta$-1,4-galactosyltransferase from N. meningitidis(64% of the enzyme activity with the $Mn^{+2}$$Ni^{+2}$, $Zn^{+2}$, and $Cu^{+2}$ ions could not activate the $\beta$-1,4-galactosyltransferase activity. The inhibited enzyme activity with the $Ni^{+2}$ ion was partially recovered with the $Mn^{+2}$$Fe^{+2}$, $Zn^{+2}$, and $Cu^{+2}$ ions, the $Mn^{+2}$$\beta$-1,4-galactosyltransferase activity was 1.5-fold stimulated with the non-ionic detergent Triton X-100 (0.1-5%).

• Biomolecules & Therapeutics
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• v.24 no.4
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• pp.410-417
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• 2016

Quercetin is a flavonoid usually found in fruits and vegetables. Aside from its antioxidative effects, quercetin, like other flavonoids, has a various neuropharmacological actions. Quercetin-3-O-rhamnoside (Rham1), quercetin-3-O-rutinoside (Rutin), and quercetin-3-(2(G)-rhamnosylrutinoside (Rham2) are mono-, di-, and tri-glycosylated forms of quercetin, respectively. In a previous study, we showed that quercetin can enhance ${\alpha}7$ nicotinic acetylcholine receptor (${\alpha}7$ nAChR)-mediated ion currents. However, the role of the carbohydrates attached to quercetin in the regulation of ${\alpha}7$ nAChR channel activity has not been determined. In the present study, we investigated the effects of quercetin glycosides on the acetylcholine induced peak inward current ($I_{ACh}$) in Xenopus oocytes expressing the ${\alpha}7$ nAChR. $I_{ACh}$ was measured with a two-electrode voltage clamp technique. In oocytes injected with ${\alpha}7$ nAChR copy RNA, quercetin enhanced $I_{ACh}$, whereas quercetin glycosides inhibited $I_{ACh}$. Quercetin glycosides mediated an inhibition of $I_{ACh}$, which increased when they were pre-applied and the inhibitory effects were concentration dependent. The order of $I_{ACh}$ inhibition by quercetin glycosides was Rutin${\geq}$Rham1>Rham2. Quercetin glycosides-mediated $I_{ACh}$ enhancement was not affected by ACh concentration and appeared voltage-independent. Furthermore, quercetin-mediated $I_{ACh}$ inhibition can be attenuated when quercetin is co-applied with Rham1 and Rutin, indicating that quercetin glycosides could interfere with quercetin-mediated ${\alpha}7$ nAChR regulation and that the number of carbohydrates in the quercetin glycoside plays a key role in the interruption of quercetin action. These results show that quercetin and quercetin glycosides regulate the ${\alpha}7$ nAChR in a differential manner.

• Korean Journal of Veterinary Service
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• v.43 no.1
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• pp.39-44
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• 2020

The aim of this study is to investigate how the gut microbiome shifts when pigs were exposed with low concentrations of mycotoxins, deoxynivalenol (DON) and zearalenone (ZEN) in feed. Fifteen of pigs, 15 kg in weight which were negative for PRRSV and PCV2 were purchased, acclimatized until 20 kg in weight, and randomly divided into 3 groups; the DON group (DON treated), the ZEN group (ZEN treated) and the CTL (untreated negative control). DON and ZEN administered to each group for 30 days at 0.8 mg/kg (800 ppb) and 0.20 mg/kg (200 ppb) in feed, respectively. After extraction of microbial DNA from intestine and fecal samples, sequencing procedures were performed in the Ion PGM using an Ion 316 V2 chip and Ion PGM sequencing 400 kit. The results suggested that the bacterial communities in duodenum, jejunum and ileum of the DON and ZEN groups presented low-abundant OTUs compared with the CTL group. OTUs in cecum, colon and feces were determined more than in small intestine of all three groups. However, the CTL group yielded more OTUs than other two groups in inter-group comparison. It is not fully clarified how the richness and abundance in microbiome functions in the health condition of animals, however, the exposure to DON and ZEN has caused microbial population shifts representing microbial succession and changes following the diversity and abundance of porcine gut microbiome. The metabolomic analysis correlate with microbiome analysis is needed for further study.

• Molecules and Cells
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• v.25 no.2
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• pp.272-278
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• 2008

The carbon-ion beam (CIB) generated by the heavy-ion medical accelerator in Chiba (HIMAC) was targeted to 7-day-old rice. Physiological parameters such as growth, and gene expression profiles were examined immediately after CIB irradiation. Dose-dependent growth suppression was seen three days post-irradiation (PI), and all the irradiated plants died by 15 days PI. Microarray (Agilent rice 22K) analysis of the plants immediately after irradiation (iai) revealed effects on gene expression at 270 Gy; 353 genes were up-regulated and 87 down-regulated. Exactly the same set of genes was affected at 90 Gy. Among the highly induced genes were genes involved in information storage and processing, cellular processes and signaling, and metabolism. RT-PCR analysis confirmed the microarray data.

• Journal of Microbiology and Biotechnology
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• v.26 no.1
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• pp.207-212
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• 2016

PacBio's long-read sequencing technologies can be successfully used for a complete bacterial genome assembly using recently developed non-hybrid assemblers in the absence of second-generation, high-quality short reads. However, standardized procedures that take into account multiple pre-existing second-generation sequencing platforms are scarce. In addition to Illumina HiSeq and Ion Torrent PGM-based genome sequencing results derived from previous studies, we generated further sequencing data, including from the PacBio RS II platform, and applied various bioinformatics tools to obtain complete genome assemblies for five bacterial strains. Our approach revealed that the hierarchical genome assembly process (HGAP) non-hybrid assembler resulted in nearly complete assemblies at a moderate coverage of ~75x, but that different versions produced non-compatible results requiring post processing. The other two platforms further improved the PacBio assembly through scaffolding and a final error correction.

• Bulletin of the Korean Chemical Society
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• v.27 no.9
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• pp.1323-1328
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• 2006

Mesoporous nickel intercalated aluminosilicate nanohybrid has been synthesized through a recombination reaction between the colloidal suspension of exfoliated montmorillonite nanosheets and aqueous nickel acetate solution. According to powder X-ray diffraction and field emission-scanning electron microscopic analyses, the intercalation of nickel species expands significantly the basal spacing of the host montmorillonite clay and the crystallites of the intercalation compound are assembled to form a house-of-card structure. $N_2$ adsorption-desorption isotherm measurements with BJH pore analyses clearly demonstrated that the porosity of the intercalate originates mainly from mesopores (diameter $\sim50\;\AA$) formed by the house-of-card type stacking of clay crystallites. From FT-IR and X-ray absorption spectroscopic analyses, it becomes certain that intercalated nickel ion is stabilized in an isolated $NiO_6$ octahedral unit. The present mesoporous intercalation compound is expected to be applicable as efficient catalysts or absorbents.

• Journal of Applied Biological Chemistry
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• v.48 no.1
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• pp.7-10
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• 2005

Trichoderma sp. SY most effectively produces an extracellular ${\gamma}$-L-arabinofuranosidase (AF) using arabinose as a carbon source. AF grown on cellulose as a carbon source was purified 28-fold with 4.4% yield by DEAE exchange and HQ/20 cation exchange chromatographies The purified enzyme was found to be homogeneous on SDS-PAGE with molecular weight of 89 kDa. It exhibited a high level of activity with p-nitrophenyl ${\alpha}$-L-arabinofuranoside, showing $K_m$ and $V_{max}$ values of $0.15\;{\mu}M$ and $239.85U{\cdot}mg^{-1}$, respectively and did not require any metal ion for activity. It also released p-nitrophenol from p-nitrophenol conjugated ${\beta}$-D-xylopyranoside, and ${\beta}$-D-galactopyranoside not from ${\beta}$-D-glucopyranoside.

• Korean Journal of Agricultural Science
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• v.42 no.4
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• pp.415-421
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• 2015

Ca is material to used in Chinese cabbage (Brasica rapa L. spp. pekinensis). The variation of inorganic ions and GSLs in Chinese cabbage cultivated to control additional Ca contents in slaked lime. The additional fertilizer of slaked lime differ four grade that 0 g (Ca-0), 0.28 g (Ca-1), 0.56 g (Ca-2), 0.84 g (Ca-3) are week intervals with a total of 8 times after transplanting. Inorganic ions in Chinese cabbage ('Bulam plus') were analyzed to use inductively coupled plasma atomic emission spectometry(ICP). The more additional slaked lime input, the more almost macronutrients contents were high except Ca. Ca contents were higher in Ca-0 (153.10) and lower in Ca-3 (130.55 mg/kg dry weight, DW). GSLs were identified based on peak retention time in previous results of our laboratory. Seven GSLs including two aliphatic (gluconapin, glucobrassicanapin), one aromatic (gluconasturtiin), four indolyl (glucobrassicin, neoglucobrassicin, 4-methoxyglucobrassicin, 4-hydroxyglucobrassicin) were detected using HPLC. Progoitrin, 4-methoxyglucobrassicin, and gluconasturtiin contents increased in proportion to the input in additional slaked lime. Total GSLs contents were Ca-0 (11.95), Ca-1 (17.02), Ca-2 (19.63), Ca-3 ($17.11{\mu}mol/g$ dry weight, DW). Total Ca and GSLs contents (Ca-1,2,3; mean 17.92) are higher than non treatment (Ca-0; $11.95{\mu}mol/g$ DW).

• Textile Coloration and Finishing
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• v.27 no.1
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• pp.62-69
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• 2015

To improve the color stability of the bioplastic containing sorghum extract, sorghum extract was chelated by a metal ion. The chelating activity was quantitatively evaluated under the various conditions. Chelation of sorghum extract by Cu(II) was determined by reaction with pyrocatechol violet, whereas Fe(II) chelation was investigated by forming complexes with ferrozine. Chelation of sorghum extract was increased rapidly with increasing concentrations of metal salt and sorghum extract. At a 0.1g/L metal salt addition level, the chelating activity of Fe(II) and Cu(II) were 66.7% and 54.2%, respectively. According to the chelation pH conditions, the sorghum extract was chelated almost 100% by Fe(II) above the pH 6.5. It was confirmed that Fe(II) was a strong chelator of sorghum extract than Cu(II). The sorghum extract chelated with metal salt exhibit higher thermal stability. The bioplastic containing chelated sorghum extract showed relatively less color change than the control.

• Bulletin of the Korean Chemical Society
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• v.35 no.3
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• pp.793-797
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• 2014

To develop a methodology for absolute determination of the surface areal density of functional groups on organic and bio thin films, medium energy ion scattering (MEIS) spectroscopy was utilized to provide references for calibration of X-ray photoelectron spectroscopy (XPS) or Fourier transformation-infrared (FT-IR) intensities. By using the MEIS, XPS, and FT-IR techniques, we were able to analyze the organic thin film of a Ru dye compound ($C_{58}H_{86}O_8N_8S_2Ru$), which consists of one Ru atom and various stoichiometric functional groups. From the MEIS analysis, the absolute surface areal density of Ru atoms (or Ru dye molecules) was determined. The surface areal densities of stoichiometric functional groups in the Ru dye compound were used as references for the calibration of XPS and FT-IR intensities for each functional group. The complementary use of MEIS, XPS, and FT-IR to determine the absolute surface areal density of functional groups on organic and bio thin films will be useful for more reliable development of applications based on organic thin films in areas such as flexible displays, solar cells, organic sensors, biomaterials, and biochips.