• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.3
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• pp.224-228
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• 1990

Cabbage contained high peroxidase activity among tested plant sources. The cabbage peroxi-dase can replace horseradish peroxidase to assay glucose with glucose oxidase. The amount of glucose can be determined quantitatively by glucose oxidase-cabbage peroxidase. The opti-mum pH and temperature for enzymatic glucose determination by glucose oxidase-cabbage peroxidase were 6.0 and 35-45$^{\circ}C$ respectively. The glucose assay was inhibited by addition of various metal salts such as mercuric chloride lead acetate silver nitrate ammonium molyb-date sodium tunstate and cupric sulfate. The relationship between absorbance and amount of glucose was linear up to 8.33 mM glucose in the assay mixture under the assay conditions.

• BMB Reports
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• v.36 no.3
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• pp.326-331
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• 2003

The fission yeast cells that contained the cloned glutathione synthetase (GS) gene showed 1.4-fold higher glutathione (GSB) content and 1.9-fold higher GS activity than the cells without the cloned GS gene. Interestingly, $\gamma$-glutamylcysteine synthetase activity increased 2.1-fold in the S. pombe cells that contained the cloned GS gene. The S. pombe cells that harbored the multi copy-number plasmid pRGS49 (containing the cloned GS gene) showed a higher level of survival on solid media with cadmium chloride (1 mM) or mercuric chloride ($10\;{\mu}M$) than the cells that harbored the YEp357R vector. The 506 bp upstream sequence from the translational initiation point and N-terminal8 amino acid-coding region were fused into the promoteriess $\beta$-galactosidase gene of the shuttle vector YEp367R to generate the fusion plasmid pUGS39. Synthesis of $\beta$-galactosidase from the fusion plasmid pUGS39 was significantly enhanced by cadmium chloride and NO-generating S-nitroso-N-acetylpenicillamine (SNAP) and sodium nitroprusside (SN). It was also induced by L-buthionine-(S,R)-sulfoximine, a specific inhibitor of $\gamma$-glutamylcysteine synthetase (GCS). We also found that the expression of the S. pombe GS gene is regulated by the Atf1-Spc1-Wis1 signal pathway.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.2
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• pp.100-104
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• 2013

Zoysiagrass (Zoysia japonica Steud.) is an important forage and turfgrass that spreads by stolons and rhizomes. Zoysiagrass stolon can be used directly for Agrobacterium-mediated genetic transformation by exploiting the potential of direct shoot formation. However, surface sterilization of field-grown stolons is difficult and remains to be explored. We developed an effective surface sterilization and culture method using the stolon explant for infection with Agrobacterium tumefaciens. Among various treatments, sequential disinfection in 30% bleach for 15 min followed by 0.1% mercuric chloride for 25 min resulted in the highest number of clean stolons. The efficacy of mercuric chloride was increased under vacuum conditions by incubating at 800 mbar for 5 min. The inclusion of 2.5 mg/l amphotericin B further prevents fungal growth in in vitro cultures. This protocol would speed up the development of transgenic plants by utilizing field-grown stolon nodes.

• Journal of Life Science
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• v.20 no.6
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• pp.838-844
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• 2010

A fibrinolytic enzyme of Streptomyces corcohrussi from soil sediment was purified by chromatography using DEAE-Sephadex A-50 and Sephadex G-50. The analysis of SDS-polyacrylamide gel suggested that the purified enzyme is a homogeneous protein and the molecular mass is approximately 34 kDa. The purified enzyme showed activity of 0.8 U/ml in a plasminogen-rich fibrin plate, while its activity in a plasminogen-free fibrin plate was only 0.36 U/ml. These results suggested that the purified enzyme acts as a plasminogen activator. The fibrinolytic activity of the enzyme under the supplementation of protease inhibitors, $\varepsilon$-ACA, t-AMCHA and mercuric chloride in the enzyme reaction was less than 24%, indicating that it could be modulated by the plasmin and/or fibrinogen inhibitors involved in the fibrinogen-to-fibrin converting process. As time passed, $Zn^{2+}$, a heavy metal ion, inhibited the activity to 34.1%. The optimum temperature of the purified enzyme was approximately $50^{\circ}C$ and over 92% of the enzyme activity was maintained between pH 5.0 and 8.0. Therefore, our results provide a potential fibrinolytic enzyme as a noble thrombolytic agent from S. corcohrussi.

• Environmental Analysis Health and Toxicology
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• v.9 no.1_2
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• pp.25-35
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• 1994

Many nephrotoxic agents exert their effect primarily on the cells of the proximal tubules. We used the LLC-$PK_1$, kidney epithelial cell line as a model system for studies on nephrotoxicity and investigated whether the uptake of $\alpha$-methylglucose($\alpha$-MG) could serve as a parameter to assess effects of nephrotoxicants on the functional integrity of the cells at an early time of toxicity. The enzyme leakage test which has been used to be as a conventional cytotoxic parameter in vitro, was conducted to compare with $\alpha$-MG uptake. Treatment with cisplatin for 24 and 48 hours significantly increased activities of lactate dehydrogenase and $\gamma$-glutamyltransferase in culture medium at a concentration of 50$\mu$M. However, above 100$\mu$M of concentration, activities of these enzymes in media were dramatically decreased by cisplatin. These observations indicate that cisplatin has direct inhibitory effect on the activities of these enzymes and make it doutful to use enzyme leakage test to demonstrate damage of kidney cells by chemicals such as cisplatin over the appropriate range of concentration. Cisplatin inhibited $\alpha$-MG uptake at a low concentration which enzymes were not leaked. Also cadmium chloride and mercuric chloride which are acutely nephrotoxic in vivo, significantly inhibited $\alpha$-MG uptake at a low concentration. These results indicate that the uptake of $\alpha$-methylglucose in LLC-$PK_1$cell line is a useful biomarker for the study of nephrotoxicity.

• Korean Journal of Veterinary Research
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• v.30 no.2
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• pp.203-214
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• 1990

A total of 166 strains of Salmonella (S) typhimurium var copenhagen isolated from pigeons (164 strains) and aquatic birds (2 strains) were examined for the biochemical characteristics and plasmid profiles. All the strains were sensitive to ampicillin, chloramphenicol, gentamicin, kanamycin and sulfadimethoxine. But 13 strains(7.8%) were resistant to streptomycin (Sm), 2 (1.2%) to tetracycline, 2 (1.2%) to rifampicin, and 1 (0.6%) to nalidixic acid. Among drug resistant strains, only one strain resistant to Sm contained conjugative R plasmid which was fertility inhibition and incompatibility group $I_{\alpha}$. All the strains were sensitive to cobalt chloride, cupric sulfate, lead nitrate, mercuric chloride and silver nitrate. Of 166 isolates, 6 (3.6%) were resistant to sodium arsenate and 1 (0.6%) to potassium tellurite. Among 166 isolates, 1 (0.6%) was colicinogenic, 12 (7.2%) sucrose fermenters, and 166 (100%) maltose fermenters. Plasmid profiles were confirmed as being 4 or 5 plasmids, and their molecular weight ranged 3.2 to 60 megadalton (MD). All the strains harbored 60 Md plasmid. There are three patterns by the plasmid profile, 150 isolates (90.4%) were pattern I (3.2, 3.5, 33, 60Md), 14 (8.4%) pattern II (3.2, 3.5, 29, 60Md), and 2 (1.2%) pattern III (4.2, 7.8, 8.5, 15, 60Md). S typhimurium var copenhagen strains containing 60Md plasmid were resistant to killing by 90% normal guinea pig serum.

• Toxicological Research
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• v.19 no.2
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• pp.153-159
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• 2003

Localization of mercury compounds was investigated in selective regions of the male reproductive tract using autometallography. The results demonstrated that mercury was observed in Sertoli and Leydig cells in testis, but not in the epithelial cells of rete testis and germ cells. In the efferent ductule, mercury compounds were observed in the cytoplasmic compartments of epithelial cells in the proximal and common regions, while they were observed in the supranuclear cytoplasmic compartments in the conus region. In the epididymis, the compounds were observed in the cytoplasmic compariments of narrow and basal cells, but not in the principal cells of the initial segment. In contrast, the compounds were evenly detected in the cytoplasmic compartments of principal cells in the caput. In the corpus and caudal epididymis, the compounds were observed in the basal region of principal cells. The data shows that mercury is differentially accumulated in the male reproductive tract in a region-specific manner.

• YAKHAK HOEJI
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• v.48 no.4
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• pp.241-246
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• 2004

Mercury is a widespread metal and consequently there are large populations that currently exposed to low levels of mercury. Endotoxin is a component of the gram-negative bacteria and promotes inflammatory responses. The present study was designed to determine the impact of mercury on lymphocytes phenotype populations and endotoxin-induced inflammatory cytokine expressions in immune organ, spleen and thymus. Male BALB/c mice were exposed continuously to 0, 0.3, 1.5, 7.5, or 37.5 ppm of mercuric chloride in drinking water for 14 days and at the end of the treatment period, lipopolysaccharide (LPS, 0.5 mg/kg) was injected intraperitoneally 2 h prior to euthanasia. The dose-range of mercury used did not cause hepatotoxicity. Mercury at 7.5 and 37.5 ppm dose-dependently decreased CD3$^{+}$ T lymphocytes in spleen; both CD4$^{+}$ and CD8$^{+}$ single positive lymphocyte populations were decreased. Exposure to 7.5 and 37.5 ppm of mercury decreased the CD8$^{+}$ T lymphocyte population in the thymus, whereas double positive CD4$^{+}$ / CD8$^{+}$ and CD4$^{+}$ thymocytes were not altered. Mercury altered LPS-induced inflammatory cytokine gene expressions such as, tumor necrosis factor $\alpha$, interferon ${\gamma}$, and interleukin-12 in spleen and thymus. Results indicated that decreases in T lymphocyte populations in immune organs and altered cytokine gene expression may contribute to the immune-modulative effects of inorganic mercury.ganic mercury.

• Journal of Microbiology and Biotechnology
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• v.5 no.4
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• pp.206-212
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• 1995

A strain BL-29, which produces a extracellular lytic enzyme on E. coli was isolated from the soil. The strain was identified as belonging to the genus Bacillus sp. The lytic enzyme was purified to homogeneity by ion exchange chromatography and gel filtration. Specific activity of the purified enzyme was 28, 850 U/mg protein and yield of the enzyme was 5$%$. The purified enzyme showed a single band on SDS-PAGE and its molecular weight was estimated to be 31, 000 by SDS-polyacrylamide gel electrophoresis and gel filtration column chromatography. The optimum temperature and pH were $55^{\circ}C$ and pH 10.0, respectively. The enzyme was stable at $45^{\circ}C$ but enzyme activity was reduced by up to 50$%$ when the temperature was raised to $55^{\circ}C$ for 15 min. Stable range of pH was from 5.0 to 11.0. but Enzyme activity was inhibited by lead-acetate, mercuric chloride, ethylene glycol-bis-[$\beta$-aminoethyl ether]-N, N, $N^1, $N^1$-tetraacetic acid (EGTA), and ethylenediamine tetraacetic acid (EDTA), but not affected considerably by treatment with other chemical reagents.

• Journal of Microbiology and Biotechnology
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• v.1 no.2
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• pp.90-95
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• 1991

A ${\alpha}-galactosidase{\;}({\alpha}-D-galactoside$ galactohydrolase; EC 3.2.1.22) was purified from the culture filtrate of Penicillium purpurogenum by DEAE-cellulose column chromatography, gel filtration of Bio gel p-l00, and subsequent SP-Sephadex C-25 chromatography. The final preparation thus obtained showed a single band on polyacrylamide disc-gel and SDS-polyacrylamide gel electrophoresis. The molecular weight and isoelectric point were determined to be 63,000 and pH 4.0 by SDS-polyacrylamide gel electrophoresis and isoelectric focusing, respectively. The galactosidase exhibited maximum activity at pH 4.5 and $55^{\circ}C$, and was stable between pH 2 and 5, and also stable up to $40^{\circ}C$. The enzyme activity was not affected considerably by treatment with other metal compounds except mercuric chloride and silver nitrate. Copra galactomannan was finally hydrolyzed to galactose, mannose and mannobiose through the sequential actions of the purified galactosidase and mannanase from the same strain. The enzyme hydrolyzed melibiose and raffinose, but not lactose.