Schultz J R, Clarke C F
Department of Chemistry and Biochemistry, University of California, Los Angeles 90095-1569, USA.
Biofactors. 1999;9(2-4):121-9. doi: 10.1002/biof.5520090206.
Ubiquinol (QH2) is a lipid-soluble molecule that participates in cellular redox reactions. Previous studies have shown that yeast mutants lacking QH2 are hypersensitive to treatment with polyunsaturated fatty acids (PUFAs) indicating that QH2 can function as an antioxidant in vivo. In this study the effect of 1 mM linolenic acid on levels of Q6 and Q6H2 is assessed in both wild-type and respiration-deficient (atp2 delta) strains. The response of Q-deficient mutants to other forms of oxidative stress is further characterized to define those conditions where QH2 acts as an antioxidant. Endogenous antioxidant defense systems were also assessed in wild-type, Q-deficient, and atp2 delta strains. Superoxide dismutase (SOD) activity decreased and catalase activity increased in both Q-deficient and atp2 delta mutants compared to wild-type cells, suggesting that such changes result from the loss of respiration rather than the lack of Q.
泛醇（QH2）是一种参与细胞氧化还原反应的脂溶性分子。先前的研究表明，缺乏QH2的酵母突变体对多不饱和脂肪酸（PUFA）处理高度敏感，这表明QH2在体内可作为抗氧化剂发挥作用。在本研究中，评估了1 mM亚麻酸对野生型和呼吸缺陷型（atp2δ）菌株中Q6和Q6H2水平的影响。进一步表征了Q缺陷突变体对其他形式氧化应激的反应，以确定QH2作为抗氧化剂发挥作用的条件。还评估了野生型、Q缺陷型和atp2δ菌株中的内源性抗氧化防御系统。与野生型细胞相比，Q缺陷型和atp2δ突变体中的超氧化物歧化酶（SOD）活性降低，过氧化氢酶活性增加，这表明这些变化是由呼吸丧失而非Q缺乏导致的。
