酮醇酸还原异构酶(英語:ketol-acid reductoisomerase,EC 1.1.1.86 (页面存档备份,存于互联网档案馆))是一种以NAD+或NADP+为受体、作用于供体CH-OH基团上的氧化还原酶。这种酶能催化以下酶促反应:
- (R)-2,3-二羟基-3-甲基丁酸 + NADP+ (S)-2-羟基-2-甲基-3-氧代丁酸 + NADPH + H+
酮醇酸还原异构酶还能将2-乙酰-2-羟基丁酸催化转化为2,3-二羟基-3-甲基戊酸。
参考文献
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