The mode of binding of NADPH and oxidized glutathione to the flavoenzyme glutathione reductase has been determined by x-ray crystallography. Furthermore, two intermediates of the reaction have been produced in the crystal and have been structurally elucidated. All these analyses were done at 0.3 nm resolution. The results allow the stereochemical description of the mechanism of the enzyme. The ...

The role of exogenous spermidine (Spd) in alleviating low temperature (LT) stress in mung bean (Vigna radiata L. cv. BARI Mung-3) seedlings has been investigated. Low temperature stress modulated the non-enzymatic and enzymatic components of ascorbate-glutathione (AsA-GSH) cycle, increased H₂O₂ content and lipid peroxidation, which indicate oxidative damage of seedlings. Low temperature reduced...

Glutathione/ glutathione disulfide and ascorbic acid /dehydroascorbateare two major redox pairs that control the redox-state in a developing seed.Recently these redox compounds have been shown to exert strong positive effectson embryo development in several plants including white spruce. A picture isemerging that early-stage embryo development occurs best in the presence of a<lb...

Human erythrocytes were incubated with 3H-glycine to label the glutathione pool. These cells were then used to determine the rate of oxidized glutathione (GSSG) transport out of erythrocytes. For 6 normal individuals, the mean transport rate was 6.7 nmole GSSG/hr/ml red cells. This transport rate would suggest a half-life of 4.7 days for the erythrocytic glutathione, which is in close agreemwnt...

Acetaminophen (AAP) overdose causes formation of peroxynitrite in centrilobular hepatocytes. Treatment with glutathione (GSH) after AAP accelerated recovery of mitochondrial GSH levels, which scavenged peroxynitrite and protected against liver injury at 6 h. The objective of this investigation was to evaluate whether GSH treatment has a long-term protective effect against AAP-induced injury and...

Reduction of glutathione disulfide (GSSG) to glutathione (GSH) by glutathione reductase (GR) enhances the efficiency of GSH-dependent antioxidant activities. However, GR-deficient (a1Neu) mice are less susceptible to acute lung injury from continuous exposure to > 95% O(2) (96 h: 6.9 +/- 0.1 g right lung/kg body versus room air 3.6 +/- 0.3) than are C3H/HeN control mice (10.6 +/- 1.3 versus 4.2...

Rat liver S-adenosylmethionine synthetase, high- and low-Mr forms, are regulated in vitro by the GSH/GSSG ratio at pH 8. The inhibition and oxidation constants for both forms have been calculated in the presence of thioltransferases. The mechanism of the reaction appeared to involve the formation of intramolecular disulfides. Increases of 3- to 4-fold in the oxidation constants for both S-adeno...

The tripeptide y-glutamyl-cysteinyl-glycine. or glutathione. protects cells against oxidative damage by its ability to react with free radicals and peroxides. From studies with human neutrophilic granulocytes deficient in glutathione metabolism. it is known that the protection by this compound is essential for the proper functioning of these cells. Previous studies have yielded conflicting esti...

Glutathione redox status is a commonly used oxidative stress biomarker. High-performance liquid chromatography-ultraviolet (HPLC-UV) and HPLC-electrochemical detection (HPLC-ECD) have been used to assess glutathione status but have potential limitations due to challenging sample preparation procedures or electrochemical signal degradation. Thus, this study aimed to validate an HPLC-ECD approach...

Crude extracts of pea shoots (Pisum sativum) catalyzed oxidized glutathione (GSSG)-dependent oxidation of NADPH which was attributed to NADPH-specific glutathione reductase. The pH optimum was 8 and the K(m) values for GSSG and NADPH were 23 mum and 4.9 mum, respectively. Reduced glutathione (GSH) inhibited the reaction. Crude extracts also catalyzed NADPH-dependent reduction of GSSG; the ratio...