Multidimensional engineering of Saccharomyces cerevisiae for improved vanillin synthesis

Background: Vanillin represents one of the most widely used flavoring agents in the world. However, microbial synthesis of vanillin is hindered by the host native metabolism that could rapidly degrade vanillin to the byproducts. Results: Here, we report that the industrial workhorse Saccharomyces cerevisiae was engineered by systematic deletion of oxidoreductases to improve the vanillin accumulation. Subsequently, we harnessed the r educed aromatic a ldehyde reduction (RARE) yeast platform for de novo synthesis of vanillin from glucose. We investigated multiple coenzyme-A free pathways to improve vanillin production in yeast. The vanillin productivity in yeast was enhanced by multidimensional engineering to optimize the supply of cofactors (NADPH and S -adenosylmethionine) together with metabolic reconfiguration of yeast central metabolism. The final yeast strain with overall 24 genetic modifications produced 365.55 ± 7.42 mg l -1 under shake-flasks, which represents the highest vanillin titer from glucose achieved to date. Conclusions: The success of vanillin overproduction in budding yeast showcases the great potential of synthetic biology for the creation of suitable biocatalysts to meet the requirement in industry. Our work lays a foundation for the future implementation of microbial production of aromatic aldehydes in budding yeast.