• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.252-256
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• 1999

Effects of gamma irradiation on lipid components, antioxidative enzyme activities and ${\alpha}-tocopherol$ in beef (M. Semitendinosus and Longissimus dorsi) were investigated. The lipid components (total cholesterol, LDL-cholesterol, HDL-cholesterol, triglyceride and phospholipid) and the antioxidative enzyme activities (glutathione sulfur transferase, catalase and total superoxide dismutase) were not significantly changed by gamma irradiation up to 10 kGy (p>0.05). However, the contents of ${\alpha}-tocopherol$ in Longissimus dorsi significantly decreased with irradiation dose (P<0.05).

• Journal of Microbiology and Biotechnology
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• v.22 no.10
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• pp.1388-1394
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• 2012

A xylanase-producing thermophilic strain, Geobacillus sp. TC-W7, was isolated from a hot spring in Yongtai (Fuzhou, China). Subsequently, the xylanase gene that encoded 407 amino acids was cloned and expressed. The recombinant xylanase was purified by GST affinity chromatography and exhibited maximum activity at $75^{\circ}C$ and a pH of 8.2. The enzyme was active up to $95^{\circ}C$ and showed activity over a wide pH range of 5.2 to 10.2. Additionally, the recombinant xylanase showed high thermostability and pH stability. More than 85% of the enzyme's activity was retained after incubation at $70^{\circ}C$ for 90 min at a pH of 8.2. The activity of the recombinant xylanase was enhanced by treatment with 10 mM enzyme inhibitors (DDT, Tween-20, 2-Me, or TritonX-100) and was inhibited by EDTA or PMSF. Its functionality was stable in the presence of $Li^+$, $Na^+$, and $K^+$, but inhibited by $Hg^{2+}$, $Ni^{2+}$, $Co^{2+}$, $Cu^{2+}$, $Zn^{2+}$, $Pb^{2+}$, $Fe^{3+}$, and $Al^{3+}$. The functionality of the crude xylanase had similar properties to the recombinant xylanase except for when it was treated with $Al^{2+}$ or $Fe^{2+}$. The enzyme might be a promising candidate for various industrial applications such as the biofuel, food, and paper and pulp industries.

• Korean Journal of Microbiology
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• v.38 no.3
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• pp.153-161
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• 2002

Sox4, a transcription factor, consists of three functional domains: an HMG-box domain as a DNA binding domain, serine rich region as a transactivation domain and glycine rich region (GRR), an unknown functional domain. Although Sox4 is known to be functionally involved in heart, B-cell and reproductive system development, its physiological function remains to be elucidated. We used pGEX expression system to develop a simple and rapid method for purifying Sox4 protein in suitable forms for biochemical studies of their functions. Unexpectedly, we observed that full-length Sox4 appears to be protease-sensitive during expression and purification in E. coli. To map the protease-sensitive site in Sox4, we generated various constructs with each of functional domains of Sox4 and purified as the GST-Sox4 fusion proteins using glutathione beads. We found that the specific cleavage site for the proteolytic enzyme, which exists in E. coli, is localized within the novel GRR of Sox4. Our study suggest that the GRR of Sox4 may a target for the cellular protease action and this cleavage in the GRR may be involved in regulating physiological function of Sox4. Additionally, our study may provide a useful method for investigating the proteolytic cleavage of the target molecule in E. coli.

• Korean Journal of Microbiology
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• v.31 no.4
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• pp.279-285
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• 1993

Alterations of the p53 gene arc among the most frequent genetic changes in human cancer and often result in increased levels of p53 protein within the malignant cells. Detection of accumulated p53 protein can be a useful prognostic tool in human cancer. In order to make polyclonal antibodies for immunohistochemical screening. human p53 gene was expressed in E. coli in the form of GST (glutathione S-transfi.:rase) fusion proteins. Two p53 gene fragments. which were N('()I small fragment encoding amino acid residues of 1-151-: and Ncol large fragment of 159-393. were subeloned into the unique BamHI site present within the pGEX-2T vector using BamHI linker and recombinant plasmids pGTNS and pGTNL were constructed. respectively. The p53 cDNA fragment (from pC53-$SN_3$,) encoding amino acid 38-145 (proline at residue 72) was amplified by polymerase chain reaction(PCR). The amplified DNA was digested with BamHI and Prull and inserted into the BamHI-Smal sites of pG EX-2T and recombinant plasmid pGTBP was constructed. After IPTG induction of these plasmids for 4 hours. fusion proteins were purified from E. coli extracts with glutathione Sepharose beads. The bound proteins were resolved by 10% SDS-polyacrylamide gel electrophoresis and the molecular weights were 54 kDa. 53 kDa and 40 kDa. respectively. Approximately one milligram of fusion proteins were purified from 1 -liter cultures.

• Journal of Nutrition and Health
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• v.37 no.1
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• pp.5-14
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• 2004

The purpose of this study was to investigate the effect of dietary sea-tangle extracts on blood glucose levels, serum lipid levels, thiobarbituric acid reactive substance (TBARS) and glutathione enzymes in diabetic rats treated with streptozotocin (STZ) Four groups of rats (Sprague-Dawley male rats, 180 - 200g) were consisted of normal rats fed control diet (C), diabetic rats fed control diet (CD), normal rats fed sea-tangl extracts diet (E), and diabetic rats fed sea-tangle extracts diet (ED). Diabetes was induced by single injection of streptozotocin (60 mg/kg B.W.). After 7 weeks, rats were sacrificed, serum glucose, serum total cholesterol, triglyceride levels and glutathione enzymes were measured. Urine was significantly higher in CD and ED groups than those of others (p < 0.05). Levels of amylase, calcium, uric acid, hemoglobin, cholesterol and low density lipoprotein (LDL)-cholesterol were different among four groups. But high density cholesterol (HDL)-cholesterol of ED group was significantly higher (p < 0.05) than other groups (C and E group) And the weekly change of serum glucose was decreased in the 3th,4th and 5th weeks. But serum triglyceride (TG) of diabetic rats fed sea-tangle extracts diet (ED) was lower than diabetic rats fed control diet (CD). Activity of hepatic microsomal G6Pase was significantly increased CD and ED groups higher than C and E group, but kidney was decreased ED group. Hepateic glutathione S-transferase (GST) of CD and ED group were significantly lower than C and E group (p<0.05), glutathione peroxidase (GPX) of E and ED group were significantly higher than C and CD group (p<0.05), glutathione reductase (GR) activities of ED group was significantly lower than other groups, malondialdehyde (MDA) of ED was lower than E and CD group, but kidney was increased significant in ED group compared to liver. These results suggested that dietary sea-tangle extracts reduce .hepatic disorders such as oxidant than kidney. In conclusion, dietary sea-tangle extracts groups reduced blood TG and hepatic MDA levels in STZ-induced diabetic rats.

• The Korean Journal of Mycology
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• v.28 no.1
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• pp.55-59
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• 2000

This study was carried out to investigate the antioxidative and chemopreventive effects of the extracts from Polyozellus multiplex, an edible mushroom through in vitro and in vivo assay. Polyozellus multiplex fractions were assayed for its antioxidative effect with colony formation assay. Polyozellus multiplex methanol extract and water fraction showed protective effects against the cytotoxicity of $H_2O_2$. The modifying effects of Polyozellus multiplex methanol extract and water fraction on the induction of carcinogenesis by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) were investigated in Wistar rats. The GSH content was decreased by MNNG treatment but was increased by adding Polyozellus multiplex water fractions. Also the activity of glutathione S-transferase and the superoxide dismutase levels were increased by the treatment of Polyozellus multiplex water fractions more than with MNNG alone. In addition to the Polyozellus multiplex water fraction increased the p53 expression as compared with the value of MNNG alone.

• Korean Journal of Microbiology
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• v.45 no.4
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• pp.416-418
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• 2009

The hepatoprotective effect of Cordyceps militaris culture broth was determined using HaM/ICR strain mice. Compared to control, the intra-peritoneal injection of benzo($\alpha$)pyrene (B($\alpha$)P) remarkably increased the activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the serum and the level of lipid peroxide (LPO) in liver tissue, which mean the liver was damaged by B($\alpha$)P. However, compared to B($\alpha$)P, oral administration of C. militaris culture broth showed decrement of AST, ALT, and LPO activities and increment GST activity and GSH level in liver tissue. These suggest that C. militaris culture broth recovered hepatic damage induced by B($\alpha$)P.

• Archives of Pharmacal Research
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• v.22 no.2
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• pp.99-107
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• 1999

A series of organosulfur compounds were synthesized with the aim of developing chemopreventive compounds active against hepatotoxicity and chemical carcinogesis. 2-(Allylthio) prazine (2-AP) was effective in inhibiting cytochrome P450 2E1-mediated catalytic activities and protein expression, and in inducing microsomal epoxide hydrolase and major glutathione S-transferases. 2-AP reduced the hepatotoxicity caused by toxicant sand elevated cellular GSH content. Development of skin tumors, pulmonary adenoma and aberrant crypt foci in colon by various chemical carcinogens was inhibited by 2-AP pretreatment. Anticarcinogenic effects of 2-AP at the stage of initiation of tumors were also observed in the aflatoxin B1 ($AFB_1$)-induced three-step medium-term hepatocarcinogenesis model. Reduction of $AFB_1$-DNA adduct by 2-AP appeared to result from the decreased formation of $AFB_1$-8,9-epoxide via suppression of cytochrome P450, while induction of GST 2-AP increases the excretion of glutathione-conjugated $AFB_1$ . 2-AP was a radioprotective agent effective against the lethal dose of total body irradiation and reduced radiation-induced injury in association with the elevation of detoxifying gene expression. 2-AP produces reactive oxygen species in vivo, which is not mediated with the thiol-dependent production of oxidants and that NF-KB activation is not involved in the induction of the detoxifying enzymes. the mechanism of chemoprotection by 2-AP may involve inhibition of the P450-mediated metabolic activation of chemical carcinogens and enhancement of electrophilic detoxification through induction of phase II detoxification enzymes which would facilitate the clearance of activated metabolites through conjugation reaction.

• The Korean Journal of Mycology
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• v.31 no.1
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• pp.34-39
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• 2003

This study was conducted to investigate effects of Ramaria botrytis methanol extract on liver damage in benzo$({\alpha})$pyrene(B$({\alpha})$P)-treated mice. The activities of serum amminotransferase, cytochrome P-450, aminopyrine N-demethylase, aniline hydroxylase and hepatic content of lipid peroxide after B$({\alpha})$P-treatment were increased than control, but those levels were significantly decreased by the treatment of Ramaria botrytis methanol extract. Whereas, the hepatic glutathione content and activities of glutathionie S-transferase and r-glutamylcysteine syntherase were increased by the treatment of Ramaria botrytis methanol extract. In addition, cytochrome P-450 1A1 izozyme protein level, remarkably increased by B$({\alpha})$P-treatment was decreased by the treatment with methanol extract of Ramaria botrytis. These results suggest that the protective effect of methanol extract of Ramaria botrytis on liver injury in B$({\alpha})$P-treated mice may be due to reduction of oxygen free radical.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.9
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• pp.3723-3727
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• 2015

The p53 tumor suppressor protein is a principal mediator of growth arrest, senescence, and apoptosis in response to a broad array of cellular damage. p53 is a substrate for the ubiquitin-proteasome system, however, the ubiquitin-conjugating enzymes (E2s) involved in p53 ubiquitination have not been well studied. UBE2Q1 is a novel E2 ubiquitin conjugating enzyme gene. Here, we investigated the effect of UBE2Q1 overexpression on the level of p53 in the MDA-MB-468 breast cancer cell line as well as the interaction between UBE2Q1 and p53. By using a lipofection method, the p53 mutated breast cancer cell line, MDA-MB-468, was transfected with the vector pCMV6-AN-GFP, containing UBE2Q1 ORF. Western blot analysis was employed to verify the overexpression of UBE2Q1 in MDA-MB-468 cells and to evaluate the expression level of p53 before and after cell transfection. Immunoprecipitation and GST pull-down protocols were used to investigate the binding of UBE2Q1 to p53. We established MDA-MB-468 cells that transiently expressed a GFP fusion proteins containing UBE2Q1 (GFP-UBE2Q1). Western blot analysis revealed that levels of p53 were markedly lower in UBE2Q1 transfected MDA-MB-468 cells as compared with control MDA-MB-468 cells. Both in vivo and in vitro data showed that UBE2Q1 co-precipitated with p53 protein. Our data for the first time showed that overexpression of UBE2Q1can lead to the repression of p53 in MDA-MB-468 cells. This repression of p53 may be due to its UBE2Q1 mediated ubiquitination and subsequent proteasome degradation, a process that may involve direct interaction of UBE2Q1with p53.