• KSBB Journal
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• v.31 no.1
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• pp.27-32
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• 2016

Several CoA transferases from Clostridium beijerinckii, C. perfringens and Klebsiella pneumoniae were examined for biosynthesis of lactate-containing polyhydroxyalkanoates (PHAs) in recombinant Escherichia coli XL1-Blue strain. The CB3819 gene and the CB4543 gene from C. beijerinckii, the pct gene from C. perfringens and the pct gene from K. pneumoniae, which encodes putative CoA transferase gene, respectively, was co-expressed with the Pseudomonas sp. MBEL 6-19 phaC1437 gene encoding engineered Pseudomonas sp. MBEL 6-19 PHA synthase 1 ($PhaC1_{Ps6-19}$) to examine its activity for the construction of key metabolic pathway to produce poly(3-hydroxybutyrate-co-lactate) [P(3HB-co-LA)]. The recombinant E. coli XL1-Blue expressing the phaC1437 gene and CB3819 gene synthesized poly(3-hydroxybutyrate) [P(3HB)] homopolymer to the P(3HB) content of 60.5 wt% when it was cultured in a chemically defined medium containing 20 g/L of glucose and 2 g/L of sodium 3-hydroxybutyrate. Expression of the phaC1437 gene and CB4543 gene in recombinant E. coli XL1-Blue also produced P(3HB) homopolymer to the P(3HB) content of 51.2 wt% in the same culture condition. Expression of the phaC1437 gene and the K. pneumoniae pct gene in recombinant E. coli XL1-Blue could not result in the production of PHAs in the same culture condition. However, the recombinant E. coli XL1-Blue expressing the phaC1437 gene and the C. perfringens gene could produce poly(3-hydroxybutyrate-co-lactate [P(86.4mol%3HB-co-13.7 mol%LA) up to the PHA content of 10.6 wt% in the same culture condition. Newly examined CoA transfereases in this study may be useful for the construction of engineered E. coli strains to produce PHA containing novel monomer such lactate.

• Journal of Preventive Medicine and Public Health
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• v.39 no.2
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• pp.135-140
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• 2006

Objectives : Polymorphisms of genes from glutathione Stransferases (GSTs) and N-acetyltransferase 2 (NAT2) have been associated with increased susceptibility to various cancers. Previous results showed that East Asians such as Koreans, Japanese and Chinese have a much higher frequency of the GSTM1 and GSTT1 null genotypes and NAT2 rapid acetylator type. Therefore, we investigated the association between the polymorphic types of GSTs (GSTM1, GSTT1, GSTP1) and NAT2 and the incidence of gastric cancer which is one of the most prevalent cancers among the East Asians. Methods : It was performed in a case-control study consisting of 238 healthy subjects and 108 cancer patients (54 distal and 54 proximal carcinomas). We also evaluated the association between GSTs and NAT2 and the risk factors for gastric cancer such as alcohol consumption, smoking, H. pylori infection, family history of gastric cancer, and tumor location. Results : In our study, the percentage of cases whose hometown was rural was higher than those of controls (odds ratio (OR) =2.88; 95% CI=1.72-4.76), and the frequency of the lower socio-economic status increased significantly in patients (OR=2.53; 95% CI=1.59-4.02). There was no significant difference in the GST polymorphic types between the cases and controls. However, NAT2 rapid or intermediate acetylator types were frequently detected in the cases with family history of gastric cancer (OR=1.92; 95% CI=1.79-26.0). Conclusions : These results suggest that the hometown and socio-economic status are important environmental factors for gastric carcinogenesis, and NAT2 polymorphic types could be associated with familial gastric carcinoma.

• Journal of Marine Life Science
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• v.3 no.2
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• pp.59-66
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• 2018

The assessment of level of health of the tidal flats can be evaluate by health of organisms inhabit the tidal flats. It is possible to evaluate the precise health level of organisms inhabit the tidal flats using analysis of expression of biomarker genes. The purpose of this research is to evaluate the health of the tidal flats on the west coast using biomarker genes such as heat shock protein 70 (Hsp70), heat shock protein 90 (Hsp90), glutathione S-transferases (GST) and thioredoxin (TRX). These genes are stress, immune, and antioxidant related genes that can be used to look at the health of an organism through gene expression. In this study, we collected manila clam (Ruditapes philippinarum) in 8 analysis areas on the west coast. Expression of the genes was analyzed by RT-qPCR method. Results showed that, the expression of Hsp70, Hsp90, GST and TRX genes were differentially expressed in the 8 analysis areas. In particular, the expression of Hsp90 and GST or the expression of Hsp70 and TRX were similar. This means that there is a substance that reacts specifically to each gene. Therefore, I think suggest that the based on the results of physicochemical analysis, it can be selected genes suitable for analysis. These results suggest that Hsp70, Hsp90, GST and TRX were played roles in biomarker for assessment of the health of tidal flats.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.1
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• pp.325-328
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• 2012

Objective: Glutathione S-transferases (GSTs) are important enzymes that are involved in detoxification of environmental carcinogens. Molecular epidemiological studies have been conducted to investigate the association between GSTM1 and GSTT1 homozygous deletion polymorphisms and brain tumours but results have been conflicting. The aim of this study was to clarify this problem using a meta-analysis. Methods: A total of 9 records were identified by searching the PubMed and Embase databases. Fixed- and random-effects models were performed to estimate the pooled odds ratios. Results: No significant association was found between the GSTM1 and GSTT1 homozygous deletion polymorphisms and risk of brain tumours, including glioma and meningioma. Similar negative results were also observed in both population-based and hospital-based studies. Conclusion: These findings indicate that the GSTM1 and GSTT1 polymorphisms may not be related to the development of brain tumours.

• Journal of Applied Biological Chemistry
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• v.44 no.3
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• pp.105-112
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• 2001

Insect pests can be controlled through direct application of insecticides. Insect control by residual protectants is relatively inexpensive and has an advantage of destroying all stages of infestations. The efficacy of control is largely determined by the concentration of insecticides to which the pest species is exposed. A reduction in the period of control in the field afforded by a specific level of a protectant indicates that resistance has developed. An increase in the level of protectant is required to maintain control, and the efficacy of currently used insecticides has been severely reduced by insecticide resistance in pest species. Development of resistance to particular insecticide varies with species because insecticide resistance is often correlated with increased levels of certain enzymes, which are cytochrome P450-dependent monooxygenases, glutathione S-transferases and esterases. Some sections of insecticide molecules can be modified by one or more of these primary enzymes. A reduction in the sensitivity of the action site of a xenobiotic also constitutes a mechanism of resistance. Acetylcholinesterase is a major target site for insecticide action, as are axonal sodium ion channels and ${\gamma}$-aminobutyric acid receptors. Development of reduced sensitivity of these target sites to insecticides usually occurs. This review not only may contribute to a better understanding of insecticide resistance, but also illustrates the gaps still present for a full biochemical understanding of the resistance.

• Proceedings of the Korean Society of Food Science and Nutrition Conference
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• 2004.11a
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• pp.53-60
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• 2004

The pro-apoptotic effect of phenethyl isothiocyanate (PEITC) and the role of glutathione (GSH) in sulforaphane (SFN)-induced antioxidant response element-dependent gene expression were investigated. The caspase-3 and caspase-9 activities were stimulated by PEITC. The release of cytochrome c was time- and dose- dependent. SP600125 suppressed apoptosis induced by PEITC. Similarly, this JNK inhibitor attenuated both cytochrome c release and caspase-3 activation induced by PEITC. SFN is converted to the glutathione conjugate by glutathione S-transferases (GSTs). It was accumulated in mammalian cells by up to several hundred-fold over the extracellular concentration, by conjugation with intracellular GSH. The induction of ARE by SFN was 8.6-fold higher than by SFN-NAC. The decrease in ARE expression at higher concentrations of SFN and SFN-NAC was correlated with the accelerated apoptotic cell death, with a dose-dependent activation of caspase 3 activity by SFN. Upon addition of extracellular GSH within 6 hr of treatment with SFN, the effect on ARE expression was blocked almost completely.

• BMB Reports
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• v.34 no.1
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• pp.66-72
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• 2001

To investigate the mechanism of adriamycin (ADM) resistance in the ADM resistant subline PC-14/ADM, we examined the expressions of p-glycoprotein (P-gp), topoisomerase I (Topo I) and II (Topo II), glutathione-S-transferases (GSTs), tissue transglutaminase (t-TG), epidermal growth factor receptor (EGFR), and E-cadherin and the activity of superoxide dismutase (SOD) in PC-14 and PC-14/ADM cells. There was no change in the cellular levels of P-gp, Topo I, Topo II, and the two isoforms of GSTs. However, SOD activity in PC-14/ADM cells was 2.38 fold higher than that in PC-14 cells. A marked induction of the t-TG expression was also observed in PC-14/ADM cells. In addition to those changes, expressions of EGFR and E-cadherin were down regulated in PC-14/ADM cells. Therefore, molecular modifications such as an increase in SOD activity, induction of the t-TG expression, and down regulation of EGFR and E-cadherin expressions may play important roles in PC-14/ADM cells during the development of ADM resistance.

• Toxicological Research
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• v.17
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• pp.299-304
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• 2001

Xenobiotics and their reactive intermediates bind to cellular macromolecules and/or generate oxidative stress. which provoke deleterious effects on the cell function. Induction of xenobiotic-biotrans-forming enzymes and antioxidant molecules is an important defense mechanism against such insults. A group of genes involved in the defense mechanism. e.g. genes encoding glutathione S-transferases. NAD(P)H: quinone oxidoreductase, UDP-glucuronosyltransferase (UDP-GT) and ${\gamma}$-glutamylcysteine synthetase (GGCS). have a common regulatory sequence, Antioxidant or Electrophile Responsive Element (ARE/EpRE). Recently. Nrf2. discovered as a homologue of erythroid transcription factor p45 NF-E2, was shown to bind ARE/EpRE and induce the expression of these defense genes. Mice that lack Nrf2 show low basal levels of expression and/or impaired induction of these genes. which makes the animals highly sensitive to xenobiotic toxicity. Indeed. we show here that nrf2-deficient mice had a higher mortality than did the wild-type mice when exposed to acetaminophen (APAP). Detailed analyses of APAP hepatotoxicity in the nrf2 knockout mice indicate that a large amount of reactive APAP metabolites was generated in the livers due to the impaired basal expression of two detoxifying enzyme genes, UDP-GT (Ugt1a6) and GGCS. while the cytochrome P450 content was unchanged. Thus. the studies using the nrf2 knockout mice clearly demonstrate significance of the expression of Nrf2-regulated enzymes in protection against xenobiotic toxicity.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.87-89
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• 2013

Glutathione S-transferases (GSTs) constitute a multigene family of multifunctional phase II metabolic enzymes. GSTT1, an important member of this group has a wide range of substrates including carcinogens. Total homozygous deletion or null genotype resulting in total lack of enzyme activity exists in populations for this enzyme. Since the null genotype may contribute to lower detoxification of carcinogens, this genotype is expected to increase cancer risk. The frequency of the GSTT1 null genotype is known to vary significantly among populations. However, little is known about its distribution in the hilly Kumaun region of northern India. Therefore, in this study, we determined the prevalence of the GSTT1 null polymorphism in the Kumaun popilation by conducting duplex PCR in 365 voluntary healthy individuals. The GSTT1 null genotype was detected in 18.4% of the individuals. Since GSTs play significant role in xenobiotic metabolism, the present data on GSTT1 genotype distribution should contribute in understanding genetic association with cancer risk in this understudied population.

• BMB Reports
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• v.49 no.8
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• pp.443-448
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• 2016

The arginylation branch of the N-end rule pathway is a ubiquitin-mediated proteolytic system in which post-translational conjugation of Arg by ATE1-encoded Arg-tRNA-protein transferase to N-terminal Asp, Glu, or oxidized Cys residues generates essential degradation signals. Here, we characterized the ATE1^−/− mice and identified the essential role of N-terminal arginylation in neural tube development. ATE1-null mice showed severe intracerebral hemorrhages and cystic space near the neural tubes. Expression of ATE1 was prominent in the developing brain and spinal cord, and this pattern overlapped with the migration path of neural stem cells. The ATE1^−/− brain showed defective G-protein signaling. Finally, we observed reduced mitosis in ATE1^−/− neuroepithelium and a significantly higher nitric oxide concentration in the ATE1^−/− brain. Our results strongly suggest that the crucial role of ATE1 in neural tube development is directly related to proper turn-over of the RGS4 protein, which participate in the oxygen-sensing mechanism in the cells.