Smirnov A N
Laboratory of Endocrinology, School of Biology, Moscow Lomonosov State University, U.S.S.R.
J Steroid Biochem. 1990 Aug 28;36(6):609-16. doi: 10.1016/0022-4731(90)90180-z.
A procedure for isolation of a highly-purified estrophilic hydroxysteroid dehydrogenase (EHSD) from rabbit liver, including ammonium sulphate fractionation, gel filtration, ion-exchange and affinity chromatography on estradiol-Sepharose, has been developed. The enzyme possesses NADP-dependent 3 alpha,3 beta,17 beta,20 alpha-HSD activities with a wide spectrum of androgenic, progestagenic, and estrogenic substrates. EHSD is a monomeric protein whose molecular mass determined by different methods is 35,000-39,000. The protein exhibits microheterogeneity due to the differences in molecular surface charge. The catalytic and hormone-binding properties and molecular sizes of the two protein fractions obtained by chromatography on DEAE-Toyopearl are close or identical. The enzymatic activity of EHSD is minor as compared to other HSDs from rabbit liver. However, the low values of Km, the high affinity for steroid ligands, and high tissue levels of EHSD suggest the protein to play a role in the biodynamics of sex hormones.
已开发出一种从兔肝中分离高纯度嗜雌激素羟类固醇脱氢酶（EHSD）的方法，包括硫酸铵分级分离、凝胶过滤、离子交换以及在雌二醇-琼脂糖上进行亲和层析。该酶具有依赖NADP的3α,3β,17β,20α-HSD活性，对多种雄激素、孕激素和雌激素底物都有作用。EHSD是一种单体蛋白，通过不同方法测定其分子量为35,000 - 39,000。由于分子表面电荷的差异，该蛋白表现出微不均一性。通过在DEAE- Toyopearl上进行层析获得的两个蛋白组分的催化和激素结合特性以及分子大小相近或相同。与兔肝中的其他HSD相比，EHSD的酶活性较低。然而，其低Km值、对类固醇配体的高亲和力以及在组织中的高含量表明该蛋白在性激素的生物动力学中发挥作用。
