2. Academic Validation
  3. Human dehydrogenase/reductase SDR family member 11 (DHRS11) and aldo-keto reductase 1C isoforms in comparison: Substrate and reaction specificity in the reduction of 11-keto-C19-steroids

Human dehydrogenase/reductase SDR family member 11 (DHRS11) and aldo-keto reductase 1C isoforms in comparison: Substrate and reaction specificity in the reduction of 11-keto-C19-steroids

  • J Steroid Biochem Mol Biol. 2020 May;199:105586. doi: 10.1016/j.jsbmb.2020.105586.
Satoshi Endo 1,  Yoshifumi Morikawa 2,  Yudai Kudo 3,  Koichi Suenami 2,  Toshiyuki Matsunaga 3,  Akira Ikari 3,  Akira Hara 4
Affiliations

Affiliations

  • 1 Laboratory of Biochemistry, Gifu Pharmaceutical University, Gifu, 501-1196, Japan. Electronic address: [email protected].
  • 2 Forensic Science Laboratory, Gifu Prefectural Police Headquarters, Gifu, 500-8501, Japan.
  • 3 Laboratory of Biochemistry, Gifu Pharmaceutical University, Gifu, 501-1196, Japan.
  • 4 Faculty of Engineering, Gifu University, Gifu, 501-1193, Japan.
PMID: 31926269 DOI: 10.1016/j.jsbmb.2020.105586
Abstract

Recent studies have shown that an adrenal steroid 11β-hydroxy-4-androstene-3,17-dione serves as the precursor to androgens, 11-ketotestosterone and 11-ketodihydrotestosterone (11KDHT). The biosynthetic pathways include the reduction of 3- and 17-keto groups of the androgen precursors 11-keto-C19-steroids, which has been reported to be mediated by three human enzymes; aldo-keto reductase (AKR)1C2, AKR1C3 and 17β-hydroxysteroid dehydrogenase (HSD) type-3. To explore the contribution of the enzymes in the reductive metabolism, we kinetically compared the substrate specificity for 11-keto-C19-steroids among purified recombinant preparations of four AKRs (1C1, 1C2,1C3 and 1C4) and DHRS11, which shows 17β-HSD activity. Although AKR1C1 did not reduce the 11-keto-C19-steroids, AKR1C3 and DHRS11 reduced 17-keto groups of 11-keto-4-androstene-3,17-dione, 11-keto-5α-androstane-3,17-dione (11K-Adione) and 11-ketoandrosterone with Km values of 5-28 μM. The 3-keto groups of 11KDHT and 11K-Adione were reduced by AKR1C4 (Km 1 μM) more efficiently than by AKR1C2 (Km 5 and 8 μM, respectively). GC/MS analysis of the products showed that DHRS11 acts as 17β-HSD, and that AKR1C2 and AKR1C4 are predominantly 3α-HSDs, but formed a minor 3β-metabolite from 11KDHT. Since DHRS11 was thus newly identified as 11-keto-C19-steroid reductase, we also investigated its substrate-binding mode by molecular docking and site-directed mutagenesis of Thr163 and Val200, and found the following structural features: 1). There is a space that accommodates the 11-keto group of the 11-keto-C19-steroids in the substrate-binding site. 2) Val200 is a critical determinant for exhibiting the strict 17β-HSD activity of the Enzyme, because the Val200Leu mutation resulted in both significant impairment of the 17β-HSD activity and emergence of 3β-HSD activity towards 5α-androstanes including 11KDHT.

Keywords

11-Oxygenated androgen; Aldo-keto reductase; DHRS11; GC/MS; Hydroxysteroid dehydrogenase; Specificity determinant.

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