Biotransformation to Produce Boldenone by Pichia pastoris GS115 Engineered Recombinant Strains

Abstract

Traditionally, boldenone (BD), an important hormone drug and precursor for the synthesis of other steroids, was chemically produced. At present, the method of biotransformation is usually from androst-4-ene-3,17-dione (AD) to BD, but some bottlenecks seriously limit the wide industrial application of microbial transformation to produce BD. Recently, Pichia pastoris GS115 was found to be capable of transforming the C17-one to C17-alcohol of steroids, indicating that P. pastoris GS115 contain the gene for 17Hsd, but its 3-ketosteroid-Δ1-dehydrogenase has low activity. In this study, we successfully expressed a 3-ketosteroid-Δ1-dehydrogenase KsdD2 from Rhodococcus rhodochrous DSM43269 intracellularly in P. pastoris GS115. The engineered recombinant strains P. pastoris GS115 pPIC3.5K-ksdd2 was found to be capable of transforming AD to both androst-1,4-ene-3,17-dione (ADD) and BD. The transformation of AD to ADD and BD is certainly the result of synergism between exogenous KsdD2 and endogenous 17Hsd. In this way, BD could be obtained by biotransformation from AD, and the research developed in this study could provide theory basis for the wide industrial application of microbial transformation to produce BD.