Takahashi T, Shitashige M, Okamoto T, Kishi T, Goshima K
Faculty of Pharmaceutical Sciences, Kobe-Gakuin University, Japan.
FEBS Lett. 1992 Dec 21;314(3):331-4. doi: 10.1016/0014-5793(92)81499-c.
Ubiquinone (UQ) reductase activity which reduces UQ to ubiquinol (UQH2) in rat tissues was roughly proportional to the UQH2/total UQ ratio in respective tissues. The highest activity was found in the liver, showing the highest UQH2/total UQ ratio. A greater part of liver UQ reductase activity was located in the cytosol. Within a week, the liver UQ reductase activity decreased by 80% even at -20 degrees C. The DT-diaphorase activity was stable. UQ reductase required NADPH as the hydrogen donor and was not inhibited by a less than 1 microM concentration of dicoumarol. There was no stimulation of UQ reductase in the presence of bovine serum albumin nor in Triton X-100. Yet, both stimulated DT-diaphorase. As a result, UQ reductase appeared to be a novel NADPH-UQ oxidoreductase and responsible for the UQ redox state in liver.
在大鼠组织中将泛醌（UQ）还原为泛醇（UQH2）的泛醌还原酶活性大致与各组织中的UQH2/总UQ比值成正比。肝脏中的活性最高，显示出最高的UQH2/总UQ比值。肝脏泛醌还原酶活性的大部分位于胞质溶胶中。即使在-20℃下，肝脏泛醌还原酶活性在一周内也下降了80%。DT-黄递酶活性稳定。泛醌还原酶需要NADPH作为氢供体，且不受低于1 microM浓度的双香豆素抑制。在牛血清白蛋白存在下或在Triton X-100中，泛醌还原酶均未受到刺激。然而，两者均刺激了DT-黄递酶。因此，泛醌还原酶似乎是一种新型的NADPH-泛醌氧化还原酶，并负责肝脏中的泛醌氧化还原状态。
