• BMB Reports
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• v.31 no.4
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• pp.399-404
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• 1998

In order to gain further insight on the relationship between structure and function of glutathione S-transferase (GST), the six active-site mutants, R13T, K44T, Q51A, Q64A, S65A, and D98A, of human GST P1-1 were expressed in Escherichia coli and purified to electrophoretic homogeneity by affinity chromatography on immobilized GSH. The active-site mutants showed marked differences in substrate specificity. The substitution of Gln51 with threonine resulted in a drastic decrease in the specific activities to <10% of the wild-type value. The substitution of Arg13 with threonine resulted in more decreased specific activity toward cumene hydroperoxide and in the $I_{50}$ values of S-(2,4-dinitrophenyl) glutathione and benanstatin A. These results suggest that the substitution of Arg13 with threonine changes the conformation of the active site to increase the affinity for the product or electrophilic substrate. Lys44 seems to be in the vicinity of the H-site of hGST P1-1 or may contribute to some extents to the electrophile binding.

• Journal of Korea Multimedia Society
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• v.16 no.6
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• pp.782-794
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• 2013

This paper proposes the wafer position recognition algorithm using camera. First, for eliminating the image distortions caused by the illumination and the irregular camera position, the wafer image is restored as a circle through projective transformation. Next, we use edge detection algorithm to extract the wafer's edge and then apply Generalized Symmetry Transform(GST) to extract a circle. The GST evaluates symmetry between two points by combining a distance weight function, a phase weight function, and a logarithmic mapping of the points' intensities and detecting interest regions. Trough several experiments, we found out the proposed method is able to prevent the cleaning system and the wafer from damaging.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2949-2953
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• 2012

The glutathione S transferase (GST) family is a major part of cellular defense mechanisms against endogenous and exogenous substances, many of which have carcinogenic potential. Alteration in the expression level or structure of the glutathione-S-transferase (GST) enzymes may lead to inadequate detoxification of potential carcinogens and consequently contribute to cancer development. A member of the glutathione-S-transferase (GST) family, GSTP1, is an attractive candidate for involvement in susceptibility to carcinogen-associated colorectal cancer. An $Ag{\rightarrow}G$ transition in exon 5 resulting in an Ile105Val amino acid substitution has been identified which alters catalytic efficiency. The present study investigated the possible impact of Ile105Val GSTP1 polymorphism on susceptibility to colorectal cancer. in Jordan We examined 90 tissue samples previously diagnosed with colorectal carcinoma, and 56 non-cancerous colon tissues. DNA was extracted from paraffin embedded tissues and the status of the GSTP1 polymorphism was determined using a polymerase chain reaction restriction fragment length polymorphism (RFLP) method. No statistically significant differences were found between colorectal cancer cases and controls for the GSTP1 Ile/Ile, Ile/Val and Val/Val genotypes. The glutathione S-transferase polymorphism was not associated with risk in colorectal cancer cases in Jordan stratified by age, sex, site, grade or tumor stage. In conclusion, the GSTP1 Ile105Val polymorphism is unlikely to affect the risk of colorectal cancer.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.226-226
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• 2010

Boron Nitride (BN) doped GeSbTe films were grown by the ion beam sputtering deposition (IBSD). The in-situ sheet resistance data and the x-ray diffraction patterns showed the crystallization is suppressed due to the BN incorporation. The phase change speed in BN doped GeSbTe films were investigated using the static tester equipped with nanosecond pulsed laser. The phase change speed for BN doped GST films become faster than the corresponding values for an undoped GST film. The Johnson-Mehl-Avrami(JMA) plot and Avrami coefficient for laser crystallization showed that the change in growth mode during the laser crystallization is a most important factor for the phase change speed in the BN doped GST films. The JMA results and the atomic force microscopy (AFM) images indicate that the origin of the change in the crystalline growth mode is due to an increase in the number of initial nucleation sites which is produced by the incorporated BN. In addition, the retension properties for the laser writing/erasing are remarkably improved in BN doped GeSbTe films owing to the stability of the incorporated BN.

• Journal of Microbiology and Biotechnology
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• v.17 no.9
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• pp.1546-1549
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• 2007

Chitosan oligosaccharide (COS, 3 kDa

• Journal of Microbiology and Biotechnology
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• v.14 no.1
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• pp.158-161
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• 2004

Scenedesmus spp. were cultured for 51 days in newly developed medium, KEP I (Kim and Ecopeace: initials of corresponding author and environmental company) made with Bacterio-Mineral-Water (3%, v/v) that had been bio-reacted with swine urine medium to 10% (v/v) Bold's Basal medium, and investigated for cancer chemopreventive potential by measuring the induction of quinone reductase (QR), glutathione S-transferase (GST), and reduced glutathione (GSH), and inhibition of cytochrome P450 (CYP) 1A1 activity. The activitives of QR and GST of Scenedesmus spp. cultured in KEP I medium were increased by 3.0-fold and 1.5-fold, respectively. However, Scenedesmus spp. cultured in control medium (CT) increased the activitives of QR and GST by 1.8-fold and 1.3-fold, respectively. Scenedesmus spp. in KEP I medium strongly inhibited CYP 1Al activity. These results show that Scenedesmus spp. in KEP I medium has cancer chemopreventive potential and may be a candidate for further development as a chemopreventive agent.

• Toxicological Research
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• v.13 no.4
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• pp.371-376
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• 1997

To compare the severe liver damage with the slight one on the bromobeazene metabolism in rats, the animal group described as B7 group was induced the stage of slight liver damage with 7 times bromobenzene injection every other day (400 mg/Kg body wt. i.p.), whereas B40 group was induced that of more severe liver damage with bromobeazene 40 times injection as identified with determination of serum levels of alanine aminotransferase(ALT) activity and the histopathological findings. In the present experimental animal model, the decreasing rate of glutathione(GSH) and the increasing rate of glutathione S-transferase activity to the control group were higher in B7 group than B40 group. Furthermore the single dose of bromobenzene was injected to the two groups and sacrificed at 8hr and the hepatic aniline hydroxylase(AH) activity, GSH content and GST activity were determined. The increasing rate of AH activity to the control was lower in B40 group than B7 group and the decreasing rate of GSH to the control was also lower in B40 than B7 group. Moreover, B7 group showed the increased activity of hepatic GST to the control whereas B40 group showed the decrease activity of the enzyme. And Vmax value in GST was more decreased in B40 group than B7 group.

• Korean Journal of Pharmacognosy
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• v.28 no.1
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• pp.48-53
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• 1997

This study was performed to elucidate the possible antioxidative effects of several wild plant extracts. Wild plants were extracted with methanol or water using general method. In first experiments, antioxidative effects were measured by lipid peroxidation using rat brain homogenate. Coptis japonica extract showed the highest antioxidative activity among the 15 wild plant extracts. In second experiments, rats were fed on the semipurified diets with or without Coptis japonica extracts at the level of 0.5% for 4 weeks. MDA production of liver homogenate were significantly lower in the rats fed Coptis japonica extracts (P<0.05). Cytosolic catalase. GPX, and SOD activities were not changed, whereas the activities of GST and glutathione level were significantly higher in rats fed Coptis japonica extracts (P<0.05). These results suggest that Coptis japonica extract has an antioxidative effect through increasing GST activity and glutathione level and decreasing MDA production.

• Journal of Embryo Transfer
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• v.25 no.4
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• pp.273-279
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• 2010

Follicular cystic follicles (FCFs) show delayed regression with persistent follicle growth. However, the mechanism by which follicles are persistently grown remains unclear. Glutathione S-transferases (GSTs) are drug-metabolizing and detoxification enzymes that are involved in the intracellular transport and metabolism of steroid hormones. In this study, a proteomic analysis was performed to identify whether GST expression is changed in bovine FCFs and to predict the interactions between GST and other proteins. Normal follicles and FCFs were classified based on their sizes (5 to 10 mm and 25 mm). In bovine follicles, GST mu 1 (GSTM1) was detected as a differentially expressed protein (DEP) and significantly up-regulated in FCFs compared to normal follicles (p<0.05). Consistent with the proteomic results, semi-quantitative PCR data and western blot analysis revealed an up-regulation of GSTM1 in FCFs. Expression levels of aromatase and dehydrogenase proteins were changed in FCFs. These results show that the up-regulation of GSTM1 that is observed in bovine FCFs is likely to be responsible for the persistent follicle growth in FCFs as the activity of aromatase and the dehydrogenases.

• Korean Journal of Acupuncture
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• v.19 no.2
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• pp.51-56
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• 2002

Induction of phase II enzymes such as quinone reductase (QR) and glutathione S-transferase (GST) is considered a major mechanism of protection against initiation of carcinogenesis. The present study was performed to evaluate the chemopreventive activity of Acori Graminei Rhizoma aqua-acupuncture solution (AGRAS) and Acori Graminei Rhizoma water-extracted solution (AGRWS) by measuring the induction of phase II enzymes. AGRAS and AGRWS are potent inducers of quinone reductase activity in murine hepatoma Hepa1c1c7 cells. The levels of GSH and GST was increased sightly with AGRAS and AGRWS. These results suggest that AGRAS and AGRWS may act as blocking agents against carcinogenesis by induction of phase II enzymes.