Systems engineering of Saccharomyces cerevisiae for synthesis and accumulation of vanillin

Abstract

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. 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 reduced aromatic aldehyde 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 further enhanced by systems 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. Taken together, our work lays a foundation for the future implementation of vanillin production from glucose in budding yeast. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=109 SRC="FIGDIR/small/545388v1_ufig1.gif" ALT="Figure 1"> View larger version (31K): org.highwire.dtl.DTLVardef@19c47dcorg.highwire.dtl.DTLVardef@131eb80org.highwire.dtl.DTLVardef@5c5a8forg.highwire.dtl.DTLVardef@13d6485_HPS_FORMAT_FIGEXP M_FIG TOC C_FIG