Fig. 1
Comparison of oxygen transfer rate (OTR, measured in shake flasks) and dissolved oxygen tension (DOT, measured in microtiter plates) measured by a RAMOS and a BioLector device, respectively. A mastermix of medium and cells was used to start the experiment in both systems simultaneously. The non-induced cultures served as references. The induction for the induced cultures took place after 7 h (blue arrows) by the addition of IPTG (0.1 mM final concentration in cultures). The maximum oxygen transfer capacity (OTRmax) was calculated after Meier et al. [46] (dashed line). Cultivation conditions for E. coli Tuner(DE3)/pRhotHi-2-EcFbFP in RAMOS device (a): 8 mL Wilms-MOPS mineral medium in each 250 mL flask, shaking frequency 350 rpm, shaking diameter 50 mm. Cultivation in the BioLector device (b): 800 µL Wilms-MOPS mineral medium per well in a 48-Flowerplate with DOT optodes, sealed with a sandwich membrane (m2p-labs), 37 °C, shaking frequency 1400 rpm and shaking diameter 3 mm