Orr W C, Sohal R S
Department of Biological Sciences, Southern Methodist University, Dallas, Texas 75275.
Arch Biochem Biophys. 1992 Aug 15;297(1):35-41. doi: 10.1016/0003-9861(92)90637-c.
Oxygen free radicals and hydroperoxides have been postulated to play a causal role in the aging process, implying that antioxidant enzymes may act as longevity determinants. Catalase (H2O2:H2O2 oxidoreductase; EC1.11.1.6) is the sole enzyme involved in the elimination of H2O2 in Drosophila melanogaster; glutathione peroxidase being absent. A genomic fragment containing the Drosophila catalase gene was used to construct transgenic Drosophila lines by means of P element-mediated transformation. Enhanced levels of catalase (up to 80%) did not prolong the life span of flies, nor did they provide improved protection against oxidative stress induced by hyperoxia or paraquat treatment. However, enhanced resistance to hydrogen peroxide was observed in the overexpressors.
氧自由基和氢过氧化物被认为在衰老过程中起因果作用，这意味着抗氧化酶可能是寿命的决定因素。过氧化氢酶（H2O2：H2O2氧化还原酶；EC1.11.1.6）是果蝇中唯一参与消除H2O2的酶；果蝇中不存在谷胱甘肽过氧化物酶。通过P因子介导的转化，利用包含果蝇过氧化氢酶基因的基因组片段构建转基因果蝇品系。过氧化氢酶水平的提高（高达80%）并没有延长果蝇的寿命，也没有提供更好的保护以抵御由高氧或百草枯处理诱导的氧化应激。然而，在过表达果蝇中观察到对过氧化氢的抗性增强。
