Protective Role of Schizosaccharomyces pombe Spp1 against Oxidative Stress Induced by Peroxide Compounds

The Schizosaccharomyces pombe spp1⁺ gene encoding a putative member of the PPPDE superfamily was cloned into an E. coli-yeast shuttle vector pRS316, which resulted in the recombinant plasmid pYSTP. The encoded sequence shares a homology with the counterparts of Arabidopsis thaliana, Picea sitchensis and Chaetomium globosum. The S. pombe cells harboring pYSYP were shown to contain a significantly higher level of the spp1⁺ mRNA than the control cells, indicating that the cloned gene is genuinely functional, and they showed a better growth n liquid media than the control cells. The S. pombe cells harboring pYSTP gave rise to an enhanced survival in liquid medium with hydrogen peroxide (H₂O₂), tert-buty1 bydroeroxide (t-BOOH) or tert-butylhydroquinone (t-BHQ) than the vector control cells. Under stress, the S. pombe cells harboring pYSTP showed slighly lower reactive oxygen species(ROS) level than the vector control cells. The total glutathione (GSH) content is higher in the S. pombe cells harboring pYSTP than the vector control cells. In brief, the S. pombe spp1⁺ gene plays a protective role in the defensive response to oxidative stress.