Abstract ▼ AI-Helper

Glutathione reductase (GR) plays an essential role in defense mechanism against reactive oxygen species by sustaining the reduced status of an antioxidant, glutathione, in cell. We constructed a recombant plasmid pET-18a that overexpresses Brassica campestris GR (BcGR) in Escherichia coli. For compa...

Glutathione reductase (GR) plays an essential role in defense mechanism against reactive oxygen species by sustaining the reduced status of an antioxidant, glutathione, in cell. We constructed a recombant plasmid pET-18a that overexpresses Brassica campestris GR (BcGR) in Escherichia coli. For comparative analyses, E. coli GR (EcGR) was also subcloned in the same method. The transformed E. coli accmulated a high level of GR transcripts upon IPTG induction. Also, Western blot analysis showed an overproduction of the BcGR protein in soluble fractions of the transformed E. coli extracts. Treated with oxidative stress generating reagents, such as, paraquat, salicylic acid, and cadmium, the BcGR overproducing E. coli exhibited a higher level of growth and survival rate than the control E. coli strain, but it was not as high as the E. coli strain transformed with the inducible EcGR. Although amino acid sequences of BcGR and EcGR share 37.3% identity, all the functionally known important residues are conserved between them. In conclusion, it appears that the eukaryotic BcGR properly functions in a prokaryotic system and provides protection against the oxidative damages in E. coli.