Selenium participates in the antioxidant defense mainly through a class of selenoproteins, including thioredoxin reductase. Epigallocatechin-3-gallate (EGCG) is the most abundant and biologically active catechin in green tea. Depending upon the dose and biological systems, EGCG may function either as an antioxidant or as an inducer of antioxidant defense via its pro-oxidant action or other unid...

OBJECTIVE Cellular redox balance is regulated by enzymatic and nonenzymatic systems and freely diffusible nitric oxide (NO) promotes antioxidative mechanisms. We show the NO-dependent transcriptional regulation of the antioxidative thioredoxin system. METHODS AND RESULTS Incubation of rat pulmonary artery smooth muscle cells (RPaSMC) with the NO donor compound S-nitroso-glutathione (GSNO, 100...

Escherichia coli B contains a cytidine diphosphate reductase system which utilizes reduced triphosphopyridine nucleotide to effect the reduction of cytidine diphosphate to deoxycytidine diphosphate (1, 2). Two components, thioredoxin and thioredoxin reductase, have been identified as oxidation-reduction carriers between TPNH and cytidine diphosphate. Thioredoxin is a low molecular weight protei...

Activity of the cysteine adducts of the cysteine proteinases papain and thaumatopain can be recovered by treatment with thioredoxin, thioredoxin reductase and NADPH. Recovery of proteinase activity did not occur if any of the components of the thioredoxin system were omitted, or if thioredoxin or thioredoxin reductase were heat-inactivated. Such an enzyme-mediated process may be of significance...

The active site sequence of T4 thioredoxin, Cys-Val-Tyr-Cys, has been modified in two positions to Cys-Gly-Pro-Cys to mimic that of Escherichia coli thioredoxin. The two point mutants Cys-Gly-Tyr-Cys and Cys-Val-Pro-Cys have also been constructed. The mutant proteins have similar reaction rates with T4 ribonucleotide reductase as has the wild-type T4 thioredoxin. Mutant T4 thioredoxins with Pro...

Thioredoxin reductase (TrxR) is a central component in the thioredoxin system by involving catalyzing reduction of thioredoxin, which critical for organism survival. Because this essential, it promising target novel antimicrobial agents. Herein, we solved 1.9 Å high‐resolution structure TrxR from Acinetobacter baumannii ( Ab TrxR), Gram‐negative, pathogenic bacterium and drug‐resistant superbug...

Malaria parasites adapt to the oxidative stress during their erythrocytic stages with the help of vital thioredoxin redox system and glutathione redox system. Glutathione reductase and thioredoxin reductase are important enzymes of these redox systems that help parasites to maintain an adequate intracellular redox environment. In the present study, activities of glutathione reductase and thiore...

Thioredoxins are small ubiquitous proteins that display different functions mainly via redox-mediated processes. The facultatively photosynthetic bacterium Rhodobacter capsulatus harbours at least two genes for thioredoxin 1 and 2, trxA and trxC. It is demonstrated that thioredoxin 2 of R. capsulatus can partially replace the thioredoxin 1 function as a hydrogen donor for methionine sulfoxide r...

Thioredoxins are small proteins of approximately 12 kD that reduce disulfide bridges of target proteins by the reversible formation of a disulfide bridge between two neighboring Cys residues present in the active site (Try-Cys-Gly-Pro-Cys). Thioredoxins have been found to regulate a variety of biological reactions in prokaryotic and eukaryotic cells (Holmgren, 1985). In higher plants, two thior...