Fig. 3: Enhancing butyl acetate production through increasing the availability of acetyl-CoA and dynamically expressing the atf1 gene.

a Introduction of isopropanol synthesis pathway (shaded in purple) and deletion of thiolase genes. The pathways in purple arrows represent the regeneration of acetyl-CoA. There are five annotated genes encoding thiolase in C. saccharoperbutylacetonicum, only two (in red) of which could be deleted (see Supplementary Note 2). b The fermentation results for butyl acetate (BA) production with various mutant strains corresponding to the genetic manipulations in (a). Data are presented as mean values ± SD (n = 3). c Four promoters associated with the biosynthesis of acetyl-CoA or alcohols in the pathway were selected to drive the expression of atf1. d The fermentation results for BA production with various mutant strains in which different promoters were used to drive the expression of atf1 as illustrated in (c). Data are presented as mean values ± SD (n = 3). Key genes in the pathway: adh alcohol dehydrogenase, bdh butanol dehydrogenase, ctfAB CoA transferase, sadh secondary alcohol dehydrogenase, hydG putative electron transfer protein, pfl pyruvate formate lyase, ald aldehyde dehydrogenase. Source data underlying Fig. 3b and d are provided as a Source Data file.