Longo 1996 J Biol Chem

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Longo VD, Gralla EB, Valentine JS (1996) Superoxide dismutase activity is essential for stationary phase survival in Saccharomyces cerevisiae. Mitochondrial production of toxic oxygen species in vivo. J Biol Chem 271:12275-80.

» PMID: 8647826 Open Access

Longo VD, Gralla EB, Valentine JS (1996) J Biol Chem

Abstract: Yeast lacking copper-zinc superoxide dismutase (CuZnSOD), manganese superoxide dismutase (SOD), catalase T, or metallothionein were studied using long-term stationary phase (10-45 days) as a simple model system to study the roles of antioxidant enzymes in aging. In well aerated cultures, the lack of either SOD resulted in dramatic loss of viability over the first few weeks of culture, with the CuZnSOD mutant showing the more severe defect. The double SOD mutant died within a few days. The severity reversed in low aeration; the CuZnSOD mutant remained viable longer than the manganese SOD mutant. To test whether reactive oxygen species generated during respiration play an important role in the observed cellular death, growth in nonfermentable carbon sources was measured. All strains grew under low aeration, indicating respiratory competence. High aeration caused much reduced growth in single SOD mutants, and the double mutant failed to grow. However, removal of respiration via another mutation dramatically increased short term survival and reversed the known air-dependent methionine and lysine auxotrophies. Our results suggest strongly that mitochondrial respiration is a major source of reactive oxygen species in vivo, as has been shown in vitro, and that these species are produced even under low aeration.

Bioblast editor: Gnaiger E

Cited by

  • Komlódi T, Sobotka O, Gnaiger E (2021) Facts and artefacts on the oxygen dependence of hydrogen peroxide production using Amplex UltraRed. Bioenerg Commun 2021.4. https://doi:10.26124/BEC:2021-0004

Labels: MiParea: Respiration, Genetic knockout;overexpression  Pathology: Aging;senescence  Stress:Oxidative stress;RONS, Hypoxia  Organism: Saccharomyces cerevisiae 

Preparation: Intact cells 

Coupling state: ROUTINE 

MitoFit 2021 AmR-O2 

Selected quotes

  • Even though the most dramatic defects have been observed for the cells lacking the cytoplasmic CuZnSOD, the MnSOD is nonetheless essential in its compartment. The fast loss of viability of CuZnSOD null mutants under normal but not low aeration may indicate that the mitochondrial enzymes are able to prevent migration of reactive oxygen species to the cytoplasm under low but not normal environmental oxygen levels.
  • MnSOD was more important than CuZnSOD for survival in low oxygen. This result has implications for higher organisms, because the dissolved oxygen concentration that most mammalian cells are exposed to is close to our low aeration conditions, making it likely that MnSOD plays a more important role than has been previously realized, in spite of its lower abundance.