Fig. 5
Scale-up of the MBE production using the E. coli coculture in high-cell density fed-batch fermentations. A and B Time profiles of MBE and the intermediate BCA –isobutanol and isopentanol– concentrations, cell density (OD600) and glucose consumed are represented for the coculture RQ5.2/CB1.2 at different inoculation ratios (indicated in the grey box on top of each plot) (A) and for the RQ5.2 strain alone with exogenous addition of isobutanol (B). The vertical dashed lines indicate the end of the batch phase and the start of the fed-batch phase. “First” and “Second” labels indicate the time when IPTG, propionate and isobutanol (only in B) were added to the culture. OD600 and glucose consumed are depicted in the same axis. C Time profile of RQ5.2 percentage in the fed-batch bioreactor cocultivation at different inoculation ratios. The two dashed-dotted lines on the left delimit the time frame when the batch phase was concluded, the two on the middle the time frame when the first induction was carried out, and the two on the right the time frame of the second induction. Error bars represent the standard deviation of three technical replicates