About Gluteradoxin / GLRX:
Glutaredoxins are glutathione-dependent enzymes that form part of the glutathione system. They consist of around one hundred amino acids and are found in a variety of species.
The most common use of glutaredoxins is in skincare. Glutaredoxins are potent antioxidants and work in conjunction with glutathione and thioredoxin to help achieve smoother higher-quality skin.
Glutaredoxin uses an active centre disulfide bond, like thioredoxin. The bond exists in either a reduced or oxidized state. The bond allows glutaredoxins to carry electrons in the synthesis of DNA by ribonucleotide reductase.
Glutaredoxin offers an antioxidant defence at the cellular level. The enzyme is able to reduce potentially harmful compounds such as the protein derived methionine sulfoxide reductase.
Glutaredoxin may also help organisms defend against hydrogen peroxide. Researchers found that overexpression of glutaredoxin (GRX) helps to the regulation of the redox state, preventing hydrogen peroxide from inducing cell death.
GRX may also protect cells from apoptoses following H202inducted oxidation. It does this by suppressing the conversion of protein phosphatase from 2A to Akt.
GRX interacts with a variety of compounds both in vivo and in vitro. The heavy metal cadmium, for instance, is an inhibitor of GRX when present in the body.
GRX also relies heavily on the presences of other enzymes to perform its function. The enzyme depends on the presence of a variety of cofactors. When present, GRX can increase dethiolation rate vastly.
Like thioredoxins, GRXs are small oxidoreductases of around 12 kD. The first time researchers identified GRXs was as a hydrogen donor to ribonucleotide reductase in model lab organisms. It was only later that their other functions were discovered and GRXs became acknowledged as an essential component of the glutathione system.
GRXs catalyze the reduction of both mixed disulfides and single-disulfides.
In the reduction of mixed disulfides, researchers believe that GRX operates using a reaction called deglutathionylation to reduce them. The mode of action of thioredoxins is different. These reduce using specific reductases while GRX is reduced by glutathione.
The mechanisms and interactions of GRXs are much less studied than thioredoxin. Most of the work on GRXs has happened in organisms that do not photosynthesize, like mammals, yeast and E.coli.
Current knowledge of the actions and mechanisms of glutaredoxin are still in development as scientists study the molecule further. It is clear that it provides crucial cell- and DNA-preserving activity, which make it an interesting study candidate.