title: Heterologous expression and characterization of a 3-ketosteroid-∆1-dehydrogenase from Gordonia neofelifaecis and its utilization in the bioconversion of androst-4,9(11)-dien-3,17-dione.
abstract: 3-Ketosteroid-∆1-dehydrogenase (KstD), a key enzyme in microbial steroid catabolism, catalyzes the trans-axial elimination of the C1 and C2 hydrogen atoms of the A-ring from the polycyclic ring structure of 3-ketosteroids, and it was usually used to transform androst-4-ene-3,17-dione (AD) to produce androsta-1,4-diene-3,17-dione. Here, the KstD from Gordonia neofelifaecis was expressed efficiently in Escherichia coli. E. coli cells expressing KstD3gorwere subjected to the investigation of dehydrogenation activity for different steroids. The results showed that KstD3gorhas a clear preference for steroid substrates with 3-keto-4-ene configuration, and it exhibits higher activity towards steroid substrates carrying a small or no aliphatic side chain than towards substrates having a bulky side chain at the C-17 atom. The recombinant strain could efficiently convert androst-4,9(11)-dien-3,17-dione into androst-1,4,9(11)-trien-3,17-dione (with conversion rate of 96%). 1(2)-Dehydrogenation of androst-4,9(11)-dien-3,17-dione is one of the key steps in glucocorticoid production. To the best of our knowledge, this is the first study reporting on the conversion of androst-4,9(11)-dien-3,17-dione catalyzed by recombinant KstD; the expression system of KstD3gorreported here would have an impact in the industrial production of glucocorticoid in the future.
authors.affiliation: College of Life Sciences, Sichuan Normal University, Chengdu, 610061, People's Republic of China.
authors.forename: Weiyi
authors.initials: W
authors.lastname: Wang
authors.affiliation: College of Life Sciences, Sichuan Normal University, Chengdu, 610061, People's Republic of China.
authors.forename: Fanglan
authors.initials: F
authors.lastname: Ge
authors.affiliation: College of Life Sciences, Sichuan Normal University, Chengdu, 610061, People's Republic of China.
authors.forename: Caihong
authors.initials: C
authors.lastname: Ma
authors.affiliation: College of Life Sciences, Sichuan Normal University, Chengdu, 610061, People's Republic of China.
authors.forename: Jiang
authors.initials: J
authors.lastname: Li
authors.affiliation: College of Life Sciences, Sichuan Normal University, Chengdu, 610061, People's Republic of China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Ren
authors.affiliation: College of Life Sciences, Sichuan Normal University, Chengdu, 610061, People's Republic of China. liwei001@sicnu.edu.cn.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.affiliation: College of Life Sciences, Sichuan Normal University, Chengdu, 610061, People's Republic of China.
authors.forename: Jinsong
authors.initials: J
authors.lastname: Fu
keywords: 3-Ketosteroid- ∆1-dehydrogenase; Androst-1,4,9(11)-trien-3,17-dione; Bioconversion; Gordonia neofelifaecis NRRL B-59395