Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C1260386 (GSH)
 38,102 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The presence of glutathione transferase (GST; EC 2.5.1.18) in Escherichia coli ATCC 25922, E. coli ATCC 25422, Proteus vulgaris ATCC 8427, Pseudomonas aeruginosa ATCC 27853, Klebsiella oxytoca CIP 666, K. oxytoca AF 101, Enterobacter cloacae CIP 6085, Serratia marcescens CIP 6755, and Proteus mirabilis AF 2924 was investigated. Using 1-chloro-2,4-dinitrobenzene as substrate, GST activity was found in the glutathione-(GSH-)affinity-purified fraction of all strains tested. SDS-PAGE analysis of GSH-affinity-purified enzyme indicated that the GSTs of all these bacteria are dimers of two identical subunits of Mr about 22,500. Rabbit antiserum directed against the major isoenzyme present in Proteus mirabilis AF 2924, Pm-GST-6.0, was used to investigate the antigenic properties of bacterial GSTs. Western blot analysis indicated that a GST antigenically identical to Pm-GST-6.0 is present in Enterobacter cloacae CIP 6085, Escherichia coli ATCC 25422 and Proteus vulgaris ATCC 8427, but absent in Escherichia coli ATCC 25922, Klebsiella oxytoca CIP 666, K. oxytoca AF 101 and Serratia marcescens CIP 6755. The presence of Pm-GST-6.0, but not mammalian GST, increased the MIC values of amikacin, ampicillin, cefotaxime, cephalothin and nalidixic acid for E. coli ATCC 25922. It is suggested that bacterial GST may represent a defense against the effects of antibiotics.
J Gen Microbiol 1989 Nov
PMID:Glutathione transferase in bacteria: subunit composition and antigenic characterization. 261 80

Analogues of GSH in which either the gamma-glutamyl or the glycyl moiety is modified were synthesized and tested as both substrates for and inhibitors of glutathione S-transferases (GSTs) 7-7 and 8-8. Acceptor substrates for GST 7-7 were 1-chloro-2,4-dinitrobenzene (CDNB) and ethacrynic acid (ETA) and for GST 8-8 CDNB, ETA and 4-hydroxynon-trans-2-enal (HNE). The relative ability of each combination of enzyme and GSH analogue to catalyse the conjugation of all acceptor substrates was similar with the exception of the combination of GST 7-7 and gamma-L-Glu-L-Cys-L-Asp, which used CDNB but not ETA as acceptor substrate. In general, GST 7-7 was better than GST 8-8 in utilizing these analogues as substrates, and glycyl analogues were better than gamma-glutamyl analogues as both substrates and inhibitors. These results are compared with those obtained earlier with GSH analogues and GST isoenzymes 1-1, 2-2, 3-3 and 4-4 [Adang, Brussee, Meyer, Coles, Ketterer, van der Gen & Mulder (1988) Biochem. J. 255, 721-724] and the implications with respect to the nature of their active sites are discussed.
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PMID:Interaction of rat glutathione S-transferases 7-7 and 8-8 with gamma-glutamyl- or glycyl-modified glutathione analogues. 261 14

A series of GSH analogues with modifications at the gamma-glutamyl moiety was synthesized and purified by following peptide chemistry methodology. Benzyl, benzyloxycarbonyl and t-butyloxycarbonyl protective groups were used to protect individual amino acid functional groups. The formation of peptide bonds was accomplished through coupling of free amino groups with active esters, generated by reaction of the carboxylate functions with dicyclohexylcarbodi-imide and 1-hydroxybenzotriazole. The protecting groups in the tripeptides were removed in a single step by using Na in liquid NH3. Precautions were taken in order to prevent oxidation of the thiol function in the cysteine residue. Thus GSH analogues containing both L- and D-glutamic acid and L- and D-aspartic acid, coupled to cysteinylglycine through both the alpha- and the omega-carboxylate group, were synthesized. Also, decarboxy-GSH and deamino-GSH, lacking one functional group in the glutamate moiety, were prepared. The spontaneous non-enzyme-catalysed nucleophilic reaction of these GSH analogues with the electrophilic model substrate 1-chloro-2,4-dinitrobenzene showed appreciable rate differences, indicating the importance of intramolecular interactions in determining the nucleophilic reactivity of the thiol function in the cysteine residue. In particular, the free amino group in the gamma-L-glutamic acid residue appears to play a crucial role in activating the thiol group in GSH. In an adjacent paper [Adang, Brussee, Meyer, Coles, Ketterer, van der Gen & Mulder (1988) Biochem. J. 255, 721-724] these results are compared with those obtained in a study on the ability of these GSH analogues to act as a co-substrate in the glutathione S-transferase-catalysed conjugation reaction with 1-chloro-2,4-dinitrobenzene.
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PMID:Synthesis and nucleophilic reactivity of a series of glutathione analogues, modified at the gamma-glutamyl moiety. 290 8

Methanol dissimilatory enzymes detected in the methanol autotroph Xanthobacter H4-14 were a typical phenazine methosulphate-linked methanol dehydrogenase, a NAD+-linked formate dehydrogenase, and a dye-linked formaldehyde dehydrogenase that could be assayed only by activity stains of polyacrylamide gels. This same methanol dehydrogenase activity was found in ethanol-grown cells and was apparently utilized for ethanol oxidation. Formaldehyde dehydrogenase activities were investigated in Paracoccus denitrificans, Xanthobacter H4-14, and Pseudomonas AM1. P. denitrificans contained a previously reported NAD+-linked, GSH-dependent activity, but both Xanthobacter H4-14 and Pseudomonas AM1 contained numerous activities detected by activity stains of polyacrylamide gels. Induction studies showed that in Xanthobacter H4-14, a 10 kDal polypeptide, probably a dehydrogenase-associated cytochrome c, was co-induced with methanol dehydrogenase, but the formaldehyde and formate dehydrogenases were not co-regulated. Analogous induction experiments revealed similar patterns in P. denitrificans, but no evidence for co-regulation of dissimilatory activities in Pseudomonas AM1.
J Gen Microbiol 1985 Sep
PMID:Methanol dissimilation in Xanthobacter H4-14: activities, induction and comparison to Pseudomonas AM1 and Paracoccus denitrificans. 293 86

The more A + T rich fractionated component (FII DNA) of the Halobacterium halobium genome constitutes one third of the total DNA and upon isolation consists of covalently closed circular DNA (pHH1 and minor cccDNA) and nonsupercoiled sequences. We have investigated the physical organization of the non cccDNA in FII by a chromosome walk using one copy of the halobacterial insertion element ISH1 as a start point. This chromosome walk led to the isolation of 160 kb of chromosomal DNA containing 70 kb of FII DNA covalently linked to more G + C rich sequences (FI DNA). Copies of three previously characterized insertion elements (ISH1, ISH2, and ISH26) as well as at least 10 other repeated sequences are clustered within this chromosomal FII DNA "island". Unique sequences are found in the FI DNA flanking the FII DNA island as well as in 40 kb of FI DNA surrounding the bacterio-opsin gene. The presence of pHH1 in H. halobium and closely related species correlates with the occurrence of the characterized chromosomal FII DNA island. Halophilic purple membrane producing isolates YC81819-9, GN101, SB3 and GRA lack pHH1 and the 70 kb FII DNA, but contain all of the FI DNA sequences tested. We propose that pHH1 and this chromosomal FII DNA are characteristic genomic components of H. halobium and closely related species, and, that the 70 kb FII DNA might represent a large insertion in the chromosome of H. halobium and closely related species. The conservation of both FI and FII DNA sequences can be used for strain classification and determination of evolutionary relationships among halo-bacteria.
Mol Gen Genet 1985
PMID:Genome organization in Halobacterium halobium: a 70 kb island of more (AT) rich DNA in the chromosome. 298 57

Levels of the polyamines spermidine and putrescine and the major intracellular thiols glutathione (GSH), glutathionylspermidine (GSH-SPD) and dihydrotrypanothione [bis-(glutathionyl)spermidine); T[SH]2] were measured by high performance liquid chromatography throughout the growth cycle of the insect trypanosomatid Crithidia fasciculata. The amount of total spermidine, putrescine and glutathione (free and conjugated to spermidine) was found to be elevated during growth. Of the total spermidine, 30 to 50% was found conjugated to glutathione during the exponential growth phase, increasing to 60 to 70% at stationary phase. T[SH]2 was the principal intracellular thiol during exponential growth (12.1 to 17.4 nmol per 10(8) cells), whereas GSH-SPD was the major thiol in stationary phase (26.2 nmol per 10(8) cells). GSH levels changed little during the growth cycle and represented a constant proportion (10 to 12%) of the total intracellular glutathione. On dilution of stationary phase cells into fresh medium, a rapid decrease in GSH-SPD levels was observed to be associated with synthesis of T[SH]2. This process reached 90% completion by 15 min, with steady state achieved by 120 min. As the total spermidine and glutathione pools did not increase during this interval, it could be calculated that this rapid redistribution of metabolites resulted in the release of 13 nmol per 10(8) cells unconjugated spermidine without de novo synthesis. This mechanism for rapidly elevating the intracellular concentration of free spermidine may be advantageous to this organism in rapidly adapting to favourable growth conditions.
J Gen Microbiol 1988 Mar
PMID:Levels of polyamines, glutathione and glutathione-spermidine conjugates during growth of the insect trypanosomatid Crithidia fasciculata. 318 21

1. Single p.o. doses of paracetamol 400 and 800 mg/kg or SUR 2647 combination (free paracetamol + paracetamol-N-acetyl-DL-methionate, paracetamol/methionine ratio 2:1) equivalent to paracetamol 400 and 800 mg/kg were given to Bom:NMRI mice. Vehicle treated (1% w/v aqueous methylcellulose) mice were established as a control group. 2. All treatment groups irrespective of medication caused an initial GSH depletion. However, SUR 2647 combination 400 mg/kg caused a much earlier hepatic GSH recovery than paracetamol 400 mg/kg. SUR 2647 combination 800 mg/kg caused a higher hepatic GSH level than paracetamol 800 mg/kg. 3. There was no significant difference in the plasma ALAT level after SUR 2647 combination 400 or 800 mg/kg and the control group. Paracetamol 400 and 800 mg/kg caused significant plasma ALAT elevations compared to the control group. 4. The addition of N-acetyl-DL-methionine esterified to paracetamol, as in the SUR 2647 combination, enhances the hepatic GSH synthesizing capacity in Bom:NMRI mice after experimental overdosage and offers protection of hepatic cell integrity as assessed by plasma ALAT level compared to paracetamol alone.
Gen Pharmacol 1988
PMID:In vivo studies on toxic effects of concurrent administration of paracetamol and its N-acetyl-DL-methionine ester (SUR 2647 combination). 335 Mar 31

1. A single p.o. dose of 1% w/v methylcellulose 0.013 ml/kg was given to male Bom:NMRI mice using untreated animals as controls. 2. A circadian fluctuation was seen in the hepatic glutathione levels (GSH) of both the methylcellulose and untreated animal group. 3. The methylcellulose administration did not affect the hepatic GSH or plasma ALAT level compared to untreated animals. 4. Histological examination did not reveal any abnormalities of the stomach wall, liver or kidney during the 12 hr trial period. 5. Male Bom:NMRI mice treated with 1% w/v methylcellulose can be considered representative of untreated controls in short-term experiments studying liver GSH and plasma ALAT levels.
Gen Pharmacol 1987
PMID:Effects of methylcellulose on hepatic glutathione levels and plasma ALAT following single oral administration to male Bom:NMRI mice. 365 74

1. Specific activities of glutathione S-transferase towards four model substrates were determined in guinea-pig brain 50,000 g supernatant and compared with those obtained for liver and kidney extract. 2. By using 1-chloro-2,4-dinitrobenzene as substrate, glutathione S-transferase activity was measured in different anatomical regions of brain; cerebellum expressed the highest conjugating capacity. 3. Brain glutathione S-transferase was resolved into four major peaks (PI 6.10, 6.60, 7.15, 7.65) each having similar kinetic constants for both substrates GSH and 1-chloro-2,4-dinitrobenzene. 4. Likewise, four forms, focused at pH 6.45, 7.14, 7.50 and 8.88, were obtained from liver. 5. Unlike hepatic tissue, brain does not possess the highly alkaline form which displays Se-independent GSH peroxidase activity. 6. Several psychotropic agents, including chlorpromazine and chlorazepate, produced a considerable in vitro inhibition on brain transferase activity.
Gen Pharmacol 1982
PMID:Glutathione S-transferase activity from guinea-pig brain: a comparison with hepatic multiple forms. 681 96

1. Hepatoprotective activity of an ethanolic extract of Teucrium stocksianum was investigated against paracetamol-induced hepatic damage in mice. 2. Paracetamol at an oral dose of 0.6 g/kg produced about 94% mortality in mice while pretreatment with the plant extract (0.5 and 1 g/kg for 5 days) reduced the death rate to 0%. 3. Paracetamol (0.6 g/kg, orally) produced liver damage as manifested by significant rises in liver weight, plasma aspartate aminotransferase (AST) activity and bilirubin concentration, pentobarbitone-induced sleeping time, and by the significant depletion of reduced glutathione (GSH) in the liver. 4. Pretreatment of mice with T. stocksianum at the above doses significantly ameliorated all the paracetamol-induced signs of liver damage described above. 5. T. stocksianum did not produce any lethality or adverse effects in the livers of treated mice. 6. These results indicate that T. stocksianum ethanolic extract contains hepatoprotective constituents, and suggest further work on the isolation and characterization of these constituents which may potentially be used as hepatoprotective agents.
Gen Pharmacol 1995 Mar
PMID:Effect of Teucrium stocksianum on paracetamol-induced hepatotoxicity in mice. 759 77


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