• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.3
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• pp.394-400
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• 2015

The roots of Platycodon grandiflorum species either dried or fresh, are used as an ingredient in salads and traditional cuisine in Korea. To interpret the root proteins, a systematical and targeting analysis were carried out from diploid and tetraploid roots. Two dimensional gels stained with CBB, a total of 39 differential expressed proteins were identified from the diploid root under in vivo condition using image analysis by Progenesis Same Spot software. Out of total differential expressed spots, 39 differential expressed protein spots (${\geq}\;1.5$-fold) were analyzed using LTQ-FTICR mass spectrometry. Except two proteins, the rest of the identified proteins were confirmed as down-regulated such as Isocitrate dehydrogenase, Proteasome subunit alpha type-2-B. However, the most of the identified proteins from the explants were mainly associated with the oxidoreductase activity, nucleic acid binding, transferase activity and catalytic activity. The exclusive protein profile may provide insight clues for better understanding the characteristics of proteins and metabolic activity in various explants of the economically important medicinal plant Platycodon grandiflorum.

• Journal of Life Science
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• v.26 no.5
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• pp.531-536
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• 2016

We previously showed that NAD(P)H:quinone oxidoreductase 1 (NQO1) knockout (KO) mice exhibited spontaneous inflammation with markedly increased mucosal permeability in the gut, and that NQO1 is functionally associated with regulating tight junctions in the mucosal epithelial cells that govern the mucosal barrier. Here, we confirm the role of NQO1 in the formation of tight junctions by human colonic epithelial cells (HT29). We treated HT29 cells with a chemical inhibitor of NQO1 (dicumarol; 10 μM), and examined the effect on the transepithelial resistance of epithelial cells and the protein expression levels of ZO1 and occludin (two known regulators of tight junctions between gut epithelial cells). The dicumarol-induced inhibition of NQO1 markedly reduced transepithelial resistance (a measure of tight junctions) and decreased the levels of the tested tight junction proteins. In vivo, luminal injection of dicumarol significantly increased mucosal permeability and decreased ZO1 and occludin protein expression levels in mouse guts. However, in contrast to the previous report that the epithelial cells of NQO1 KO mice showed marked down-regulations of the transcripts encoding ZO1 and occludin, these transcript levels were not affected in dicumarol-treated HT29 cells. This result suggests that the NQO1-depedent regulation of tight junction molecules may involve multiple processes, including both transcriptional regulation and protein degradation processes such as those governed by the ubiquitination/proteasomal, and/or lysosomal systems.

• Korean Journal of Microbiology
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• v.28 no.2
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• pp.91-97
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• 1990

Complementary DNA (cDNA) coding for human cytoplasmic superoxide dismutase (SOD1) (superoxide: superoxide oxidoreductase E.C.1.15.1.1) was isolated from human liver cDNA library of $\lambda$gt11 by in situ plaque hybridization. The insery cDNA gas the 5' untranslational region (UTR) and 3'UTR of SOD1 gene. Polymerase Chain Reaction (PCR) method was used fro subcloning of SOD1 structural gene. Using synthetic sense strand primer (24mer) containing a start codon and antisense strand primer (24mer), SOD1 structural gene was selectively amplified. Amplified DNA was directly cloned into the HincII site of pUC19 plasmid. Insery cDNA was subcloned into M13 mp19 and sequenced by dideowy chain termination method with Sequenase. The nucleotide sequence of insert cDNA had an open reading frame (ORF) coding for 153 amino acid residues. The structural gene of cytoplasmic SOD was placed under the control of bacteriophage $\lambda P_{L}$ regulatory sequences, generating a highly efficient expression plasmid. The production of human SOD1 in E. coli cells was about 7% of total cellular proteins and recombinant human SOD1 possessed its own enzymatic acitivity.

• Applied Biological Chemistry
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• v.36 no.3
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• pp.178-183
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• 1993

Xylose reductase (alditol: $NADP^+$ 1-oxidoreductase, EC 1.1.1.21) from the xylose-fermenting yeast, Candida sp. BT001, was purified via salt fractionation, ion-exchange, gel filtration and affinity chromatography, and its properties were characterized. The enzyme from the yeast was active with both NADPH and NADH as coenzyme. The xylose reductase activity with NADH was approximately 51% of that with NADPH and the specific activities of purified enzyme with NADPH and NADH were 11.78 U/mg and 6.01 U/mg, respectively. Molecular weight of the purified enzyme was 31,000 on SDS-PAGE and 61,000 on gel filtration. The Km for D-xylose, NADPH, and NADH was $94.2{\times}10^{-3}M,\;0.011{\times}10^{-3}M\;and \;0.032{\times}10^{-3}M$, respectively. The purified xylose reductase had relatively higher substrate affinity for L-arabinose than other aldoses tested. The optimal pH was 6.2 and the optimal reaction temperature was $45^{\circ}C$. The thermal stability of the enzyme was for 20 minutes at $30^{\circ}C$.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.40 no.4
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• pp.403-412
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• 2014

To develop an effective skin whitening agent for cosmetics, we isolated cucurbitacin B from Cucumis sativus L. which has been used as traditional skin lighting regimen by the bioactivity-guided fractionation, and investigated the inhibitory effects of cucurbitacin B on melanogenesis. At a non-cytotoxic concentration, cucurbitacin B reduced melanin contents of B16F1 melanoma cells in a dose-dependent manner. Cucurbitacin B did not directly inhibit mushroom tyrosinase activity, but it inhibited intracellular tyrosinase activity in a dose-dependent manner. Its inhibitory mechanism on melanin biosynthesis was further assessed, and we found that cucurbitacin B significantly decreased the protein level of tyrosinase, a major melanogenic enzymes and MITF, a master transcriptional factor of melanogenesis. In addition, cucurbitacin B increased the expression of WW domain-containing oxidoreductase (WWOX) which is known to function as tumor repressor and inhibits $Wnt/{\beta}$-catenin pathway. Collectively, these results suggest that cucuritacin B from C. sativus could be used as an active ingredient for skin whitening.

• Korean Journal of Food Science and Technology
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• v.42 no.5
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• pp.605-612
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• 2010

The dietary effects of chicken treated with Hwangki-Beni Koji sauce (HBS) on reactive oxygen species (ROS) generating and scavenging related enzyme activities in rats fed with a high-fat and high-cholesterol diet were investigated. The rats (five rats per group) were divided into a normal control diet group (NC), a high-fat and high-cholesterol diet control group (HFC), HFC plus base sauce-treated chicken supplemented diet group (HFC-BS), and a HFC plus HBStreated chicken supplemented diet group (HFC-HBS), and fed for 5 weeks. Total type T (T) and type O (O) hepatic xanthine oxidoreductase in HFC-HBS were 27.91-35.78% and 24.57-31.84% lower than those of HFC and HFC-BS, respectively. In HFC-HBS compared with HFC and HFC-BS, superoxidase dismutase activity was 62.89-64.50% higher, glutathione S-transferase activity was 19.29-25.17% higher, glutathione content was 25.11-53.30% higher, and lipid peroxide content was 20.29-24.19% lower. Therefore, chicken treated with HBS may prevent liver damage by the ROS formed from a high-fat and high -cholesterol diet.

• Journal of the Korean Electrochemical Society
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• v.2 no.1
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• pp.31-37
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• 1999

Copper-containig enzyme, laccase (Rhus vernicifera) was immobilized onto gold electrode using self-assembly technique and its surface properties and catalytic activities were examined. Laccase is an oxidoreductase capable to oxidize diphenols or diamines by 4-electron reduction of molecular oxygen without superoxide or peroxide intermediates. The electrode surface were modified by $\beta-mercaptopropionate$ to have a net negative charge in neutral solution and positively charged laccase (pI=9) was immobilized by electrostatic interaction. The successful immobilization was confirmed by cyclic voltammograms which showed typical surface-confined shapes and behaviors. The amount of charge to reduce the surface was similar to the charge calculated assuming the surface being covered by monolayer. The activity of the immobilized enzyme was tested by the capbility of oxidizing a substrate, ABTS (2,2-azine-bis-(3-ethylbenzthioline-6-sulfonic acid) and it was maintained for $2\~3$ days at $4^{\circ}C$. The immobilzed laccase showed about $10\~15\%$ activity compared to that in solution. The laccase-modified electrode showed the activity of elefoocatalytic reduction of oxygen in the presence of mediator, $Fe(CN)_6^{3-}$ The addtion of azide which is an inhibitor of laccase compeletly eliminated the catalytic current.

• Korean Journal of Microbiology
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• v.41 no.4
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• pp.255-261
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• 2005

A 6.7kb DNA fragment containing the sprT gene encoding Streptomyces griseus trypsin (SGT) was cloned from Streptomyces griseus ATCC 10137, and the complete nucleotide sequence was determined. Nucleotide sequence and deduced amino acid or the EcoRI-HindIII fragment revealed the presence or the six complete ORFs containing the sprT gene and one incomplete ORF, which were named ORF1, SGT, ORF2, ORF3, ORF4, ORF5, and ORF6, respectively. ORF1 has homology with the oxidoreductases from several organisms. ORF2 and ORF3 show similarity with unknown proteins and transcription regulator that belongs to the ArsR family, respectively. ORF4 and ORF5 show homology with the peptidoglycan bound protein with LPXTG motif from Listeria monocytogenes and the membrane protein with transmembrane helix from several organisms, respectively. The last ORF, ORF6, shows homology with the lipoprotein from Streptomyces avermitilis.

• Journal of Life Science
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• v.26 no.2
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• pp.174-180
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• 2016

Dicumarol is a coumarin derivative isolated from sweet clover (Melilotus alba), and has anti-coagulant activity with the inhibitory activity of NAD(P)H quinone oxidoreductase1 (NQO1). NQO1 catalyzes the two-electron reduction of quinones to hydroquinones. Dicumarol competes with NAD(P)H for binding to NQO1, resulting in the inhibition of NQO1 enzymatic activity. The expression of matrix metalloproteinases (MMPs) has been implicated in the invasion and metastasis of cancer cells. The expression of MMPs is regulated by cytokines and signal transduction pathways, including those activated by phorbol myristate acetate (PMA). However, the effects of dicumarol on metalloproteinase (MMP)-9 expression and activity are not investigated here. This study investigated whether dicumarol inhibits MMP-9 expression and activity in PMA-treated human renal carcinoma Caki cells. Dicumarol markedly inhibited the PMA-induced MMP-9 mRNA expression and MMP-9 activity. NF-κB and AP1 promoter activity, which is important in MMP-9 expression, also decreased in dicumarol-treated cells. Furthermore, dicumarol markedly suppressed the ability of PMA-mediated migration in Caki cells. When the relevance of NQO1 in the dicumarol-mediated inhibitory effect on PMA-induced MMP9 activity was elucidated, knock-down of NQO1 with siRNA was found to have no effect on PMA-induced MMP9 activity, suggesting that the stimulating effect of dicumarol on PMA-induced MMP9 activity is independent of NQO1 activity. Taken together, the present studies suggested that dicumarol may inhibit PMA-induced migration via down-regulation of MMP-9 expression and activity.

• Molecules and Cells
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• v.20 no.1
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• pp.43-50
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• 2005

Glutaredoxin (Grx) is a small, heat-stable redox protein acting as a multi-functional glutathione (GSH)-dependent disulfide oxidoreductase. We have cloned the monothiol Grx5 gene from the genomic DNA of the fission yeast Schizosaccharomyces pombe. It has 1,904 bp, with one intron, and encodes a putative protein of 146 amino acids with a molecular mass of 16.5 kDa. Recombinant Grx5 produced functional Grx in S. pombe cells. NO-generating sodium nitroprusside (SNP, 1.0 and 2.0 mM) and potassium chloride (KCl, 0.2 and 0.5 M) increased the synthesis of ${\beta}$-galactosidase from a Grx5-lacZ fusion gene, and transcription of Grx5 was also enhanced by SNP and KCl. Synthesis of ${\beta}$-galactosidase from the Grx5-lacZ fusion was lower in Pap1-negative TP108-3C cells than in wild type KP1 cells, and when Pap1 was overproduced in KP1 cells, the level of ${\beta}$-galactosidase increased. We also found that Pap1 is involved in the induction of Grx5 by SNP and KCl. S. pombe Grx5 may play a crucial role in responses to nitrosative and osmotic stresses.