Fig. 8

Engineering strategies for heterologous production. The heterologous expression of a protein \(E_X\) that catalyses the synthesis and export of a product of interest is enforced. a Shown is the volumetric biomass productivity as a function of the expression of the heterologous protein. As expected, increasing expression results in lower biomass productivity (‘the protein burden’). b The resulting productivity \(P_X\) of the compound of interest. \(P_X\) exhibits a maximum as a function of heterologous expression. In both plots \(I_0= 440\ \upmu \text {E m}^{-2}\ \text {s}^{-1}\)