Rabbit 3-hydroxyhexobarbital dehydrogenase is a NADPH-preferring reductase with broad substrate specificity for ketosteroids, prostaglandin D2, and other endogenous and xenobiotic carbonyl compounds
作者:Satoshi Endo、Toshiyuki Matsunaga、Atsuko Matsumoto、Yuki Arai、Satoshi Ohno、Ossama El-Kabbani、Kazuo Tajima、Yasuo Bunai、Shigeru Yamano、Akira Hara、Yukio Kitade
DOI:10.1016/j.bcp.2013.08.024
日期:2013.11
for NADP(H) over NAD(H) at a physiological pH of 7.4. In the NADPH-linked reduction, 3HBD showed broad substrate specificity for a variety of quinones, ketones and aldehydes, including 3-, 17- and 20-ketosteroids and prostaglandin D(2), which were converted to 3alpha-, 17beta- and 20alpha-hydroxysteroids and 9alpha,11beta-prostaglandin F(2), respectively. Especially, alpha-diketones (such as isatin
3-羟基己异巴比妥脱氢酶(3HBD)催化将NAD(P)(+)链接的3-羟基己异巴比妥氧化为3-羟基己异巴比妥。该酶被认为是异生物醇和某些羟基类固醇的脱氢酶,但其生理功能仍然未知。我们已经纯化了兔3HBD,分离了其cDNA,并检查了其对辅酶和底物的特异性,反应方向性和组织分布。3HBD是醛酮还原酶(AKR)超家族的成员(AKR1C29),并且在7.4的生理pH值下,NADP(H)优于NAD(H)。在与NADPH相关的还原反应中,3HBD对多种醌,酮和醛(包括3-,17-和20-酮类固醇和前列腺素D(2))显示出广泛的底物特异性,它们被转化为3alpha-,17beta-和20alpha -羟基类固醇和9alpha,11beta-前列腺素F(2),分别。特别是,α-二酮(如isatin和diacetyl)和脂质过氧化衍生的醛(如4-oxo-和4-hydroxy-2-nonenals)是显示低K(m)值(0