title: Gpx1 is a stationary phase-specific thioredoxin peroxidase in fission yeast.
abstract: The genome sequence of Schizosaccharomyces pombe reveals only one gene for a putative glutathione peroxidase (gpx1(+)). The Gpx1 protein has a peroxidase activity but preferred thioredoxin to glutathione as an electron donor when examined in vitro and in vivo, and therefore is a thioredoxin peroxidase. Besides H(2)O(2), it can reduce alkyl and phospholipid hydroperoxides. Expression of the gpx1 gene was elevated at the stationary phase, and we found that it supported long-term survival of S. pombe. The mutant also exhibited some defect in the activity of aconitase, an oxidation-labile Fe-S enzyme in mitochondria. Activity of sulfite reductase, a labile Fe-S enzyme in the cytosol, was also dramatically lowered in the mutant in the stationary phase. The Gpx1 protein, without any obvious targeting sequence, was localized in mitochondria as well as in the cytosol. Therefore, Gpx1 must serve to ensure optimal mitochondrial function and cytosolic environment, especially in the stationary phase.
authors.affiliation: Laboratory of Molecular Microbiology, School of Biological Sciences, and Institute of Microbiology, Seoul National University, Kwanak-gu, Seoul 151-742, Republic of Korea.
authors.forename: Si-Young
authors.initials: SY
authors.lastname: Lee
authors.forename: Ji-Yoon
authors.initials: JY
authors.lastname: Song
authors.forename: Eun-Soo
authors.initials: ES
authors.lastname: Kwon
authors.forename: Jung-Hye
authors.initials: JH
authors.lastname: Roe
mesh_terms: D000154:Aconitate Hydratase / Q000378:metabolism; D001483:Base Sequence; D003600:Cytosol / Q000201:enzymology; D004591:Electrophoresis, Polyacrylamide Gel; D015966:Gene Expression Regulation, Fungal / Q000235:genetics / Q000502:physiology; D005978:Glutathione / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000235:genetics / Q000378:metabolism*; D008928:Mitochondria / Q000201:enzymology / Q000235:genetics; D009154:Mutation; D018384:Oxidative Stress / Q000235:genetics / Q000502:physiology; D054464:Peroxiredoxins / Q000378:metabolism*; D012568:Schizosaccharomyces / Q000201:enzymology* / Q000235:genetics; D050889:Sulfite Reductase (Ferredoxin) / Q000378:metabolism; D000094765:Glutathione Peroxidase GPX1
chemical_list: D054464:Peroxiredoxins; D005979:Glutathione Peroxidase; D050889:Sulfite Reductase (Ferredoxin); D000154:Aconitate Hydratase; D005978:Glutathione; D000094765:Glutathione Peroxidase GPX1