Figure 2 Effects of auxotrophic genes from acetyl-CoA module on cell growth and FFA production. Control: prototrophic strain;leu2 Δ: strain ScYan11 with single deletion of gene LEU2 ;trp1 Δ: strain ScYan12 with single deletion of gene TRP1 ;lys2 Δ: strain ScYan14 with single knocked out gene LYS2 . Growth curve of leu2 Δ, trp1 Δ and lys2 Δ were measured by adding exogenous leucine, tryptophan and lysine of 100, 500 and 1,000 mg/L, respectively (A, B and C). Meanwhile, fatty acid titers at fermentation endpoint (48 h) of leu2 Δ, trp1 Δ andlys2 Δ were measured (D). All data was represented as the mean ± s.d. of three clone samples.