Ribonucleoside diphosphate reductase consists of two nonidentical subunits, proteins Bl and B2. The enzyme catalyzes the reduction of ribonucleotides to the corresponding deoxyribonucleotides. The electrons required in this reduction are transported from NADPH via a flavoprotein, thioredoxin reductase, to a low molecular weight protein, thioredoxin. The reduced form of thioredoxin acts as hydro...

Myeloperoxidase produces strong oxidants during the immune response to destroy invading pathogens. However, these oxidants can also cause tissue damage, which contributes to the development of numerous inflammatory diseases. Selenium containing compounds, including selenomethionine (SeMet) and 1,4-anhydro-5-seleno-D-talitol (SeTal), react rapidly with different MPO-derived oxidants to form the ...

In P. falciparum, antioxidant proteins of the glutathione and thioredoxin systems are compartmentalized. Some subcellular compartments have only a partial complement of these proteins. This lack of key anti-oxidant proteins in certain sub-cellular compartments might be compensated by functional complementation between these systems. By assessing the cross-talk between these systems, we show for...

Ribonucleoside diphosphate reductase consists of two nonidentical subunits, proteins Bl and B2. The enzyme catalyzes the reduction of ribonucleotides to the corresponding deoxyribonucleotides. The electrons required in this reduction are transported from NADPH via a flavoprotein, thioredoxin reductase, to a low molecular weight protein, thioredoxin. The reduced form of thioredoxin acts as hydro...

Thioredoxin is a low molecular weight protein. In the oxidized form, thioredoxin-S2, it contains a single disulfide bridge formed from the 2 half-cystine residues in the molecule (1). The reduced or dithiol form of thioredoxin, thioredoxin-(SH)z, was first identified as the hydrogen donor in the reduction of ribonucleotides to deoxyribonucleotides in Escherichia coli (2). It has now been shown ...

Thioredoxins are a class of low molecular weight redox proteins that undergo reversible reduction-oxidation of two active-site cysteine residues with reduction catalyzed by the NADPH-dependent flavoenzyme thioredoxin reductase. Human thioredoxin has been shown to be identical to a previously reported leukemic cell growth factor. We now report that recombinant human thioredoxin added to minimal ...

This study explored the effects of the antioxidant astaxanthin on paraoxonase and thioredoxin reductase activities as well as on other oxidative stress parameters and on the lipid profile in hypercholesterolemic rabbits. Rabbits were fed a standard or a hypercholesterolemic diet alone or supplemented with 50, 100 and 500 mg/100 g of astaxanthin for 60 days. Antioxidant enzymes activities, lipid...

The preceding paper (1) described the purification from Escherichia coli of thioredoxin, a heat-stable, small protein involved in the reduction of cytidine diphosphate to deoxycytidine diphosphate by the cytidine diphosphate reductase system isolated from E. coli (2). Evidence was presented that thioredoxin was first reduced enzymatically with TPNH to a sulfhydryl form (thioredoxin-(SH)J, which...