Golf S W, Graef V
Steroids. 1980 Aug;36(2):167-76. doi: 10.1016/0039-128x(80)90016-1.
From rat liver microsomes a NAD: 3 alpha-hydroxy-5 alpha-pregnan-20-one oxidoreductase was isolated and purified up to a specific activity of 73 nmol/min . mg by affinity chromatography and DEAE-cellulose chromatography. Various Km-values have been determined. The enzyme exhibits highest affinity for 5 alpha-pregnane-3,20-dione and NADH. The 3-oxo group of 5 alpha-dihydrocortisone (17,21-dihydroxy-5 alpha-pregnane-3,11,20-trione) was not reduced by the purified enzyme preparation and NADH and no dehydrogenation with NAD was observed of 3 alpha,11 beta,17,21-tetrahydroxy-5 alpha-pregnan-20-one. The optimal pH for the hydrogenation of th 3-oxo group was at pH 5.3 and for the dehydrogenation at pH 8.9. Disc gel electrophoresis in presence of 0.1% sodium dodecylsulfate yielded a homogeneous preparation.
从大鼠肝脏微粒体中分离并纯化出一种NAD：3α-羟基-5α-孕烷-20-酮氧化还原酶，通过亲和层析和DEAE-纤维素层析，其比活性达到73 nmol/分钟·毫克。已测定了各种Km值。该酶对5α-孕烷-3,20-二酮和NADH表现出最高亲和力。纯化的酶制剂和NADH不会还原5α-二氢可的松（17,21-二羟基-5α-孕烷-3,11,20-三酮）的3-氧代基团，并且未观察到3α,11β,17,21-四羟基-5α-孕烷-20-酮与NAD发生脱氢反应。3-氧代基团氢化的最佳pH值为5.3，脱氢的最佳pH值为8.9。在0.1%十二烷基硫酸钠存在下进行圆盘凝胶电泳得到了均一的制剂。
