Figure 7

Comparison of phosphate-limited and -unlimited conditions in shake flasks. Comparison concerning biomass (OD and scattered light), product formation (EcFbFP fluorescence and SDS-PAGE gel) and specific productivity (fluorescence per scattered light and percent of EcFbFP band). Data from shake flask cultivations under the following conditions: 37°C, shaking diameter 50 mm, shaking frequency 350 rpm, filling volume 10 mL, modified Wilms & Reuss medium (7.5 g/L Glucose) with four different phosphate concentrations, induction with IPTG after 6 h (final concentration 0.1 mM), harvest time 26 h. Samples for SDS-PAGE were normalized to a comparable protein content and EcFbFP bands were quantified with densitometry; MW means molecular weight standard. Measurement of scattered light intensity (signal gain factor 20) and EcFbFP fluorescence (signal gain factor 45) were conducted with the BioLector prototype.