Fig. 7
From: Efficiency of acetate-based isopropanol synthesis in Escherichia coli W is controlled by ATP demand
Metabolic scenarios of isopropanol-producing cells on acetate. Arrow thickness indicates flux level. Gray arrows denote fluxes that are considered (close to) zero. a Growth/high-resource-demand scenario during N-excess: Acetate is predominantly taken up via AckA and Pta and metabolized in the TCA cycle. Biomass formation is preferred while product formation remains low. b Production/low-resource-demand scenario during N-starvation: Acetate is taken up via AckA, Pta and AtoDA. A smaller amount of it enters the TCA cycle where the glyoxylate shunt is inactive due to a lack of biomass formation. Instead, acetyl-CoA is directed toward isopropanol formation. The ratio between Thl- and ICDH-flux determines the IPA:ACO ratio