초록
<P>5α-Androstene-3,17-dione (5α-AD), an important intermediate in the synthesis of steroid drugs, is mainly synthesized by chemical methods in industry. In this work, a new biotechnological production method of 5α-AD from cheap precursors had been developed. 5α-Reductase from <I>Treponema denticola</I>, which can convert the 3-oxo-4-ene structure into 5α-reductase products, was screened and expressed in <I>MNR</I> M3Δ<I>ksdd</I>, a major AD-producing strain. The engineered <I>MNR</I> M3Δ<I>ksdd</I>/261-<I>5α</I><SUB><I>T. denticola</I></SUB> strain showed a remarkably efficient one-step transformation of phytosterols (PS) into 5α-AD. As a cofactor for the reaction of 5α-reductase, nicotinamide adenine dinucleotide phosphate (NADPH) was supplied by the overexpression of glucose-6-phosphate dehydrogenase (G6PDH) in <I>MNR</I> M3Δ<I>ksdd.</I> Finally, the conversion increased from 67.9% to 86.4% in the cofactor recycling system. This study is the first to report the transformation of PS into 5α-AD by biological methods with a considerable yield. The present study also revealed that the engineered <I>M. neoaurum</I> containing 5α-reductase and G6PDH shows a practical value in producing 5α-AD in industry and provides a reference for the industrial production of high value products from cheap raw materials.</P><P>Graphic Abstract</P><P>5α-Androstene-3,17-dione (5α-AD), an important intermediate in the synthesis of steroid drugs, is mainly synthesized by chemical methods in industry.<BR/><IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c8gc03489c'/><BR/></P>