Fig. 2

l-histidine accumulation and biomass formation of 100 FACS-isolated C. glutamicum CgHis2 variants. All variants were independently generated by chemical mutagenesis, independently isolated in a biosensor-based FACS screening and characterized in detail. A l-histidine titer and biomass after 48 h (second characterization step). Error bars of variants represent three independent technical replicates. C. glutamicum CgHis2 reference strain (grey) is displayed as mean over ten independent cultivation rounds. Note: Due to technical variation of humidity parameters during the cultivation, variants were evaluated only in comparison to the respective triplicate of controls on the same microtiter plate. Therefore, comparison of variants from all cultivation rounds was performed by B percentage improvement of l-histidine titers in comparison to the specific C. glutamicum CgHis2 starting strain control. An increased product formation of 10% was set as threshold. Data represent average values and standard deviation of three independent technical replicates