• Toxicological Research
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• 제7권2호
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• pp.231-238
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• 1991

The pesticide and carcinogen ethylene dibromide(EDB) is metabolized both by cytosolic GSH S-transferase and by microsomal mixed function oxygenase. Cytochrome P-450 IIE1 appears to be major enzyme to metabolize EDB.EDB is activated to a mutagen by enzymatic conjugation with glutathione (GSH). Such activation is an exception to the general mode of detoxification via GSH S-transferase action. The primary DNA adduct (>95) is S-[2-(N7-guanyl)ethyl] GSH and a minor adduct is S-[2-(N7-guanyl)ethyl]cysteine, which is excreted in the urine and may serve as a biomarker of damage.

• Journal of Microbiology
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• 제42권1호
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• pp.42-46
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• 2004

It has recently been reported that one of the most important factors of yeast resistance to the fungicide chlorothalonil is the glutathione contents and the catalytic efficiency of glutathione S-transferase (GST) (Shin et al., 2003). GST is known to catalyze the conjugation of glutathione to a wide variety of xenobiotics, resulting in detoxification. In an attempt to elucidate the relation between chlorothalonil-detoxification and GST, the GST of Escherichia coli was expressed and purified. The drug-hypersensitive E. coli KAM3 cells harboring a plasmid for the overexpression of the GST gene can grow in the presence of chlorothalonil. The purified GST showed chlorothalonil-biotransformation activity in the presence of glutathione. Thus, chlorothalonil is detoxified by the mechanism of glutathione conjugation catalyzed by GST.

• BMB Reports
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• 제30권4호
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• pp.296-298
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• 1997

A bacterial glutathione S-transferase from Pseudomonas sp. DJ77 has been crystallized. The crystals diffract to at least $2.3\;\AA$ resolution, and belong to the orthorhombic space group $P2_{1}2_{1}2_{1}$, with cell parameters $a=97.4\;\AA,\;b=100.3\;\AA$, and $c=46.0\;\AA$. There is one dimer molecule of pGST per crystallographic asymmetric unit. with the crystal volume per protein mass of $2.34\;\AA^3/dalton$ and a solvent content of about 47% (v/v).

• 동아시아식생활학회지
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• 제3권2호
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• pp.121-128
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• 1993

This study was intended to clarify the protective mechanism of diallyl disulfide on the carbon tetrachloride-induced hepatotoxicity in mice. It was observed that a powerfully increment of serum alanine aminotransferase activity and hepatic lipid peroxide content after carbon tetrachloride injection were markedly inhibited by the pretreatment of diallyl disulfide (20mg/kg) for 5 days. It was also observed that hepatic aminopyrine demethylase and xanthine ocidase as free radical generating enzymes as well as superoxide dismutase and catalase activities as free frdical scavenging enzymes and hepatic glutathione content were not changed by the pretreatment with diallyl disulfide. But, treatment with diallyl disulfide did signifiantly increase cytosolic glutathione S-transferase activity. However, glutathione S-transferase activity in the presence of diallyl disulfide was not affected in vitro. Therefore, it is concluded that mechanism for the observed preventive effect ofdiallyl disulfide against the carbon tetrachloride-induced hepatotoxicity can be due to the engancement of glutathione S-transferase activity.

• Archives of Pharmacal Research
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• 제10권3호
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• pp.149-152
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• 1987

The present work was undertaken to investigate the effect of diallyl disulfide on ethacrynic acid toxicity. Ethacrynic acid-induced morality and formation of lipid peroxide were inhibited by diallyl disulfide. Furthermore, decreasing effect of glutathione S-transferase and glutathione level in the liver by ethacrynic acid were reduced by diallyl disulfide. These results suggested that the inducing effect of diallyl disulfide on the ethacrynic acid metabolizing enzyme, glutathione S-transferase, is believed to be a possible detoxication mechanism for the ethacrynic acid toxicity in mice.

• Journal of Crop Science and Biotechnology
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• 제10권2호
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• pp.117-122
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• 2007

Distributions of physiological inhibitors of a tau-type pumpkin glutathione S-transferase(CmGSTU3) have been investigated in different organs of pumpkin plants, including the onion bulb and water hyacinth root. Inhibitory effects were observed in alcoholic extracts of all plant parts, but the extracts prepared from the roots of either water hyacinth or pumpkin plant showed the highest effect on CmGSTU3 toward 1-chloro-2,4- dinitrobenzene(CDNB). Results of various chromatographies indicated that a number of inhibitory substances were present in the alcoholic extract of each plant organ. Some macromolecules in the plant extracts exhibited inhibitory effects; however, the extracts might contain a large number of unknown low-molecular-weight inhibitory substances. Some of the low-molecular-weight inhibitors in water hyacinth root extract showed characteristics fluoresce under UV light.

• Toxicological Research
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• 제7권2호
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• pp.141-149
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• 1991

The treatment with 5ng/ml of mercuric chloride caused time-dependent decreases, and in the activities of GSH S-transferase and GSH-peroxidase, and in the concentration of GSH in CHO cells. Three hours after treatment of $Hg^{2+}$, the activity of GSH S-transferase was decreased to almost half value of control group and the activity of GSH-peroxidase was reduced significantly at 6 hr after treatment. The concentration of GSH was decreased 2 hr after treatment of $Hg^{2+}$ and was decreased to nearly half value of control group 3 hr after treatment.

• Parasites, Hosts and Diseases
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• 제40권4호
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• pp.173-176
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• 2002

Glutathione S-transferase (28GST) with molecular mass of 28 kDa is an anti-oxidant enzyme abundant in Clonorchis sinensis. In adult C. sinensis, 28GST was localized in tegumental syncytium, cytons, parenchyma, and sperm tails examined by immunoelectron microscopy. C. sinensis 28GST was earlier found to neutralize bio-reactive compounds and to be rich in eggs. Accordingly. it is suggested that 28GST plays important roles in phase II defense system and physiological roles in worm fecundity of C. sinensis.

• BMB Reports
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• 제56권8호
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• pp.457-462
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• 2023

Glutathione S-transferase omega 1 (GstO1) is closely associated with various human diseases, including obesity and diabetes, but its functional mechanism is not fully understood. In the present study, we found that the GstO1-specific inhibitor C1-27 effectively suppressed the adipocyte differentiation of 3T3-L1 preadipocytes. GstO1 expression was immediately upregulated upon the induction of adipocyte differentiation, and barely altered by C1-27. However, C1-27 significantly decreased the stability of GstO1. Moreover, GstO1 catalyzed the deglutathionylation of cellular proteins during the early phase of adipocyte differentiation, and C1-27 inhibited this activity. These results demonstrate that GstO1 is involved in adipocyte differentiation by catalyzing the deglutathionylation of proteins critical for the early phase of adipocyte differentiation.

• BMB Reports
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• 제30권4호
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• pp.246-252
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• 1997

Malonate decarboxylase from Acinetobacter calcoaceticus is shown to have malonyl-CoA: acetate CoA transferase. acetyl-CoA: malonate CoA transferase, and malonyl-CoA decarboxylase activity. These enzyme activities were elucidated by isotope exchange reactions. The enzyme modified by N-ethylmaleimide completely lost its malonate decarboxylase activity, whereas it still kept CoA transferases and malonyl-CoA decarboxylase activities. The existence of CoA transferases and malonyl-CoA decarboxylase activity is clear, but their physiological significance is obscure. The catalytic reactions for two eoA transfers and malonyl-CoA decarboxylation proceed via a cyclic mechanism, which is through two covalent intermediates, enzyme-Smalonyl and enzyme-S-acetyL proposed for malonate decarboxylation of the enzyme.