FIG. 4.
Fine-tuned induction of E. coli JM101(pSPZ10) and styrene epoxidation at various rates during continuous two-liquid-phase cultivation (D = 0.1 h−1). At t = −25 h, styAB expression was induced with an organic DCPK concentration of 1.7 mM. Styrene epoxidation was initiated at t = 0 by adding 40 mM styrene into the organic-phase feed tank. The other conditions were the same as in the experiment shown in Fig. 2. The results obtained during steady-states I to III were confirmed by an independent experiment, in which data deviated by at maximum 10% from those in the experiment shown. (A) Courses of biomass and acetate concentrations in the aqueous phase and of the specific O2 uptake rate (qO2) and the specific CO2 evolution rate (qCO2). (B) Styrene and styrene oxide concentrations in the organic phase and specific styrene epoxidation rates. (C) Styrene feed concentrations applied.