Improving solubility and copy number of taxadiene synthase to enhance the titer of taxadiene in Yarrowia lipolytica

Abstract

Taxadiene is an important precursor for the biosynthesis of highly effective anticancer drug paclitaxel, but its microbial biosynthesis yield is very low. In this study, we employed Yarrowia lipolytica as a microbial host to produce taxadiene. First, a “push–pull” strategy was adopted to increase taxadiene production by 234%. Then taxadiene synthase was fused with five solubilizing tags respectively, leading a maximum increase of 62.3% in taxadiene production when fused with SUMO. Subsequently, a multi-copy iterative integration method was used to further increase taxadiene titer, achieving the maximum titer of 23.7 mg/L in shake flask culture after three rounds of integration. Finally, the taxadiene titer was increased to 101.4 mg/L by optimization of the fed-batch fermentation conditions. This is the first report of taxadiene biosynthesis accomplished in Y. lipolytica, serving as a good example for the sustainable production of taxadiene and other terpenoids in this oleaginous yeast.

Keywords

• Taxadiene
• Yarrowia lipolytica
• “Push–pull” ostrategy
• Multi-copy integration
• Fed-batch fermentation