Direct Utilization of Peroxisomal Acetyl-CoA for the Synthesis of Polyketide Compounds in Saccharomyces cerevisiae

Polyketides are a class of natural products with manyapplicationsbut are mainly appealing as pharmaceuticals. Heterologous productionof polyketides in the yeast Saccharomyces cerevisiae has been widely explored because of the many merits of this modeleukaryotic microorganism. Although acetyl-CoA and malonyl-CoA, theprecursors for polyketide synthesis, are distributed in several yeastsubcellular organelles, only cytosolic synthesis of polyketides hasbeen pursued in previous studies. In this study, we investigate polyketidesynthesis by directly using acetyl-CoA in the peroxisomes of yeaststrain CEN.PK2-1D. We first demonstrate that the polyketide flaviolincan be synthesized in this organelle upon peroxisomal colocalizationof native acetyl-CoA carboxylase and 1,3,6,8-tetrahydroxynaphthalenesynthase (a type III polyketide synthase). Next, using the synthesisof the polyketide triacetic acid lactone as an example, we show that(1) a new peroxisome targeting sequence, pPTS1, is more effectivethan the previously reported ePTS1 for peroxisomal polyketide synthesis;(2) engineering peroxisome proliferation is effective to boost polyketideproduction; and (3) peroxisomes provide an additional acetyl-CoA reservoirand extra space to accommodate enzymes so that utilizing the peroxisomalpathway plus the cytosolic pathway produces more polyketide than thecytosolic pathway alone. This research lays the groundwork for moreefficient heterologous polyketide biosynthesis using acetyl-CoA poolsin subcellular organelles.

Automated summary

This study demonstrates the feasibility of synthesizing polyketides in the peroxisomes of yeast cells by directly using acetyl-CoA. The research also shows that engineering peroxisome proliferation and utilizing the cytosolic pathway can enhance polyketide production. These findings lay the groundwork for more efficient heterologous polyketide biosynthesis.