| Type: | Family | Name: | Monothiol glutaredoxin |
| Description: | Glutaredoxins [, , ], also known as thioltransferases (disulphide reductases, are small proteins of approximately one hundred amino-acid residues which utilise glutathione and NADPH as cofactors. Oxidized glutathione is regenerated by glutathione reductase. Together these components compose the glutathione system []. Glutaredoxin functions as an electron carrier in the glutathione-dependent synthesis of deoxyribonucleotides by the enzyme ribonucleotide reductase. Like thioredoxin, which functions in a similar way, glutaredoxin possesses an active centre disulphide bond []. It exists in either a reduced or an oxidized form where the two cysteine residues are linked in an intramolecular disulphide bond.Glutaredoxin has been sequenced in a variety of species. On the basis of extensive sequence similarity, it has been proposed [] that Vaccinia virusprotein O2L is most probably a glutaredoxin. Finally, it must be noted that Bacteriophage T4thioredoxin seems also to be evolutionary related. In position 5 of the pattern T4 thioredoxin has Val instead of Pro.In Saccharomyces cerevisiae(Baker's yeast), monothiol glutaredoxin 5 (Grx5p) is essential for the mitochondrial machinery involved in the synthesis and assembly of iron/sulphur centres []. Absence of Grx5p leads to constitutive oxidative damage, exacerbating that caused by external oxidants.Proteins in this group contain a conserved structural domain, PICOT-HD (amino acids 46-132 in Grx5p) []. | Short Name: | Monothiol_GRX |
