title: Crystallization and preliminary crystal structure of the complex of 17beta-hydroxysteroid dehydrogenase with a dual-site inhibitor.
abstract: Human estrogenic 17beta-hydroxysteroid dehydrogenase (17beta-HSD1) catalyzes the synthesis of 17beta-estradiol (E2) from estrone, in the ovary and peripheral tissues. While the structures of 17beta-HSD1 alone and in complex with E2 have been determined (D. Ghosh, V. Pletnev, D.-W. Zhu, Z. Wawrzak, W.-L. Duax, W. Pangborn, F. Labrie, S.-X. Lin, Structure of human 17beta-hydroxysteroid dehydrogenase at 2.20 A resolution, Structure 3 (1995) 503-513), no structures of inhibitor/enzyme complex, either modeled or from crystallography, have been reported before the submission of the present paper. The best available inhibitors are among the 'dual-site inhibitors', blocking estrogenic 17beta-HSD and the estrogen receptor. These compounds belong to a family of estradiol analogues having an halogen atom at the 16alpha position and an extended alkyl-amide chain at the 7alpha position (C. Labrie, G. Martel, J.M. Dufour, G. Levesque, Y. Merand, F. Labrie, Novel compounds inhibit estrogen formation and action, Cancer Res. 52 (1992) 610-615). We now report the crystallization of this enzyme/inhibitor complex. The complex of the best available dual-site inhibitor, EM-139, with 17beta-HSD1 has been crystallized using both cocrystallization and soaking methods. Crystals are isomorphous to the native crystals grown in the presence of 0.06% beta-octyl-glucoside and polyethyleneglycol 4000, with a monoclinic space group C2. Data at 1.8 A have been collected from a synchrotron source. Even though the size of the inhibitor is greater than that of the substrate, our preliminary X-ray-diffraction study shows that EM-139 fits into the active site in a position similar to that of estrogen. The availability of such structural data will help design more potent inhibitors of estrogenic 17beta-HSD.
authors.affiliation: Medical Research Council Group in Molecular Endocrinology, CHUL Research Center and Laval University, Sainte-Foy, Que., Canada.
authors.forename: D W
authors.initials: DW
authors.lastname: Zhu
authors.forename: R
authors.initials: R
authors.lastname: Campbell
authors.forename: F
authors.initials: F
authors.lastname: Labrie
authors.forename: S X
authors.initials: SX
authors.lastname: Lin
mesh_terms: D001051:Apoenzymes / Q000737:chemistry; D003460:Crystallization; D018360:Crystallography, X-Ray; D004958:Estradiol / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D004960:Estradiol Dehydrogenases / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000378:metabolism; D004965:Estrogen Antagonists / Q000737:chemistry / Q000494:pharmacology; D004970:Estrone / Q000378:metabolism; D005260:Female; D006801:Humans; D010053:Ovary / Q000201:enzymology
chemical_list: D001051:Apoenzymes; D004965:Estrogen Antagonists; C064480:EM 139; D004970:Estrone; D004958:Estradiol; D004960:Estradiol Dehydrogenases