Tan K H, Meyer D J, Coles B, Ketterer B
FEBS Lett. 1986 Oct 27;207(2):231-3. doi: 10.1016/0014-5793(86)81494-6.
The thymine hydroperoxide, 5-hydroperoxymethyluracil, is a substrate for Se-dependent glutathione (GSH) peroxidase and the Se-independent GSH peroxidase activity associated with the GSH transferase fraction. These enzymes may contribute to repair mechanisms for damage caused by oxygen radicals. GSH transferases 1-1, 2-2, 3-3, 4-4, 6-6, and 7-7 [(1984) Biochem. Pharmacol. 33, 2539-2540] are shown to differ considerably in their ability to utilize this substrate. For example, high activity is found in GSH transferase 6-6 which is the major isoenzyme in spermatogenic tubules where DNA synthesis is so active and faithful DNA replication so important. The activity of the purified GSH transferase isoenzymes towards 5-hydroperoxymethyluracil is comparable with their activity towards other endogenous substrates related to cellular peroxidation such as linoleate hydroperoxide and 4-hydroxynon-2-enal or biologically important xenobiotic metabolites such as benzo(a)pyrene-7,8-diol-9,10-oxide.
胸腺嘧啶过氧化氢，即5 - 氢过氧化甲基尿嘧啶，是硒依赖型谷胱甘肽（GSH）过氧化物酶以及与GSH转移酶部分相关的非硒依赖型GSH过氧化物酶活性的底物。这些酶可能有助于修复由氧自由基造成的损伤。已表明谷胱甘肽转移酶1 - 1、2 - 2、3 - 3、4 - 4、6 - 6和7 - 7 [（1984年）《生物化学与药理学》33卷，2539 - 2540页] 在利用该底物的能力上有很大差异。例如，在谷胱甘肽转移酶6 - 6中发现其活性很高，该酶是生精小管中的主要同工酶，在生精小管中DNA合成非常活跃且准确的DNA复制非常重要。纯化的谷胱甘肽转移酶同工酶对5 - 氢过氧化甲基尿嘧啶的活性与其对其他与细胞过氧化相关的内源性底物（如亚油酸过氧化氢和4 - 羟基壬 - 2 - 烯醛）或生物学上重要的外源性代谢物（如苯并(a)芘 - 7,8 - 二醇 - 9,10 - 环氧化物）的活性相当。
