Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.5.1.47 (cysteine synthase)
 625 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. The maximum activities of the enzymes for the biosynthesis of GSH (gamma-glutamyl-cysteine synthetase and GSH synthetase) have been assayed in high GSH and low GSH erythrocytes from Tasmanian Merino and Finnish Landrace sheep. 2. For the Merinos, the activities (mumol product/g haemoglobin per min +/- S.E.M. (n)) in the high and low GSH erythrocytes respectively were: gamma-glutamyl-cysteine synthetase: 0.776 +/- 0.065 (11) and 0.375 +/- 0.063 (13); and GSH synthetase: 0.069 +/- 0.003 (11) and 0.066 +/- 0.002 (13). 3. For the Finnish Landrace sheep the activities in the high and low GSH erythrocytes respectively were: gamma-glutamyl-cysteine synthetase: 0.595 +/- 0.063 (12) and 0.555 +/- 0.033 (10) and gamma-glutamyl-cysteine synthetase: 0.073 +/- 0.002 (12) and 0.070 +/- 0.002 (10). 4. gamma-Glutamyl-cysteine synthetase was markedly inhibited by physiological GSH concentrations. No evidence was found for the presence of an inhibitor of GSH biosynthesis (other than GSH) in low GSH erythrocytes from Finnish Landrace sheep. 5. Although for the Merinos the low GSH trait can be explained in terms of a diminished activity of gamma-glutamyl-cysteine synthetase, no such explanation is tenable for the Finnish Landrace sheep.
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PMID:GSH biosynthesis in glutathione deficient erythrocytes from Finnish landrace and Tasmanian merino sheep. 117 55

This study was carried out to investigate the mechanism of Rifampicin (RIF) induced glutathione (GSH) depletion in M. smegmatis. RIF at various concentrations decreased the activities of gamma glutamyl cysteine synthetase (GGCS) and GSH synthetase. Maximum decrease in the activities of biosynthetic enzymes of GSH was observed when 15 micrograms RIF ml-1 medium was incorporated in the growth medium before performing inoculations. The activity of GGCS was also decreased when three day grown M. smegmatis was exposed to 60 micrograms RIF ml-1 medium for a period of 6 h and 9 h. RIF did not alter the activity of gamma glutamyl transferase. The results of the present study demonstrate that the depletion caused by RIF in cellular GSH is due to its decreased biosynthesis whereas its degradation is not affected in M. smegmatis.
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PMID:Inhibition of cellular glutathione biosynthesis by rifampicin in Mycobacterium smegmatis. 135 83

The formic acid extracts of several glutathione-deficient strains of Escherichia coli have been assayed for the presence of the mixed disulfide of CoA and glutathione, CoASSG. Strains deficient in gamma-glutamyl-cysteine synthase (EC 6.3.2.2) produced only CoA dimer. Strains deficient in glutathione synthase (EC 6.3.2.3) produced the mixed disulfide of CoA and the gamma-glutamylcysteine dipeptide. The pool size of total CoA in the cell did not change significantly even in the absence of glutathione.
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PMID:Effect of glutathione deficiency on the pool of CoA-glutathione mixed disulfide in Escherichia coli. 611 90

S-Adenosylmethionine decarboxylase (SAMDC) is a key enzyme for the biosynthesis of spermidine. SAMDC-suppressed HL-60 cells overproduced intracellular reactive oxygen species (ROS), which led to cell growth defect and partial cell death. ROS overproduction was caused by a decrease of the total glutathione (GSH) and the ratio of reduced to oxidized GSH, and by an increase of the intracellular iron uptake. When analyzed by real-time polymerase chain reaction, the transcripts of the genes involved in the GSH synthesis (gamma-glutamyl cysteine synthetase, GSH synthetase), as well as the gene of the GSH-reducing enzyme (NADP+-dependent isocitrate dehydrogenase), were decreased dramatically in these cells. DNA-repairing genes (ATM, PARP, RAD51 and MSH2) also were not activated transcriptionally. In these situations, excessive ROS induced severe DNA damage, which could not be repaired, and ultimately led the cells to a spontaneous cell death or an early senescence state. For such cells, gamma-radiation and cisplatin, which are direct DNA-damaging agents, were very effective for promoting cell death.
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PMID:S-Adenosylmethionine decarboxylase partially regulates cell growth of HL-60 cells by controlling the intracellular ROS level: Early senescence and sensitization to gamma-radiation. 1706 47