title: Microbial introduction of a 16 alpha-hydroxyl function into the steroid nucleus.
abstract: The introduction of a 16 alpha-hydroxyl function into the steroid nucleus was studied in resting cells of Streptomyces roseochromogenes NRRL B-1233. The oxidation product of dehydroepiandrosterone (DHEA) was identified as 16 alpha-hydroxy DHEA by using thin-layer and gas-liquid chromatography. A linear relation between cell concentration and 16 alpha-OH-DHEA formation was observed. 16 alpha-Hydroxylase showed good activity at pH 8.0 for 16 alpha-OH-DHEA formation. The enzyme showed good activity at 3.1 x 10(-4) M DHEA. The oxidation products of pregnenolone, 4-androstene-3,17-dione, estrone, and 5-androstene-3 beta,17 beta-diol as well as of other substrates were identified as the 16 alpha-hydroxy steroid, respectively. The rates of microbial 16 alpha-hydroxylation were as follows: 76.9% for DHEA, 50.4% for pregnenolone, 43.9% for 4-androstene-3,17-dione, 34.3% for estrone, and 19.6% for 5-androstene-3 beta,17 beta-diol. The organism tested catalyzes 16 alpha-hydroxylation of a wide variety of steroids.
mesh_terms: D015114:Androstenediol / Q000378:metabolism; D000735:Androstenedione / Q000378:metabolism; D001189:Aryl Hydrocarbon Hydroxylases; D003687:Dehydroepiandrosterone / Q000378:metabolism; D004970:Estrone / Q000378:metabolism; D006900:Hydroxylation; D006914:Hydroxysteroids / Q000096:biosynthesis*; D011284:Pregnenolone / Q000378:metabolism; D039181:Steroid 16-alpha-Hydroxylase; D013250:Steroid Hydroxylases / Q000378:metabolism; D013302:Streptomyces / Q000378:metabolism*; D013379:Substrate Specificity
chemical_list: D006914:Hydroxysteroids; D004970:Estrone; D000735:Androstenedione; D003687:Dehydroepiandrosterone; D011284:Pregnenolone; D015114:Androstenediol; D013250:Steroid Hydroxylases; D001189:Aryl Hydrocarbon Hydroxylases; D039181:Steroid 16-alpha-Hydroxylase