Metabolic engineering approaches in yeast for increased terpenoid production.

<p>A simplified metabolic network of yeast depicting most important reactions is shown. Production of the sesquiterpenoid patchoulol is enabled via expression of patchoulol synthase (via plasmid #1 pSP-P). Overexpression of truncated HMG-CoA reductase (t<i>HMG1</i>, via plasmid #2 pSP-Pt) and fusion of FPP synthase with patchoulol synthase (via plasmid #3 pSP-FPt) to increase the flux from the central carbon precursor acetyl-CoA to the terpenoid product are highlighted in green. The disruption of α-ketoglutarate dehydrogenase (<i>KGD1</i>) to redirect the metabolic flux from citric acid cycle via pyruvate dehydrogenase bypass towards terpenoids is shown in red. Overexpression of ATP-citrate lyase (via plasmid #4 pSP-FPt-ACL) to produce cytosolic acetyl-CoA via pyruvate dehydrogenase and citric acid cycle instead of pyruvate dehydrogenase bypass is shown in blue.