Fig. 5

Comparison of the σ⁷⁰ expression systems to the THS versions controlling the expression of the reporter system mCardinal in E. coli. Architecture of the synthetic gene circuits with the toehold switches (THSs) in A σ⁷⁰V2TcR & B the σ⁷⁰V3-2LacI system. C Time course of mCardinal production by pσ⁷⁰V2TcR THS. D Time course of mCardinal production by σ.⁷⁰V3-2LacI THS. E Difference in mCardinal production between the ON and OFF states. F Fold-change difference in the red-light emission of the recombinant cells vs the wild type DH10B. The cultures were induced after 3 h of growth with aTc or IPTG accordingly. For all samples, the fluorescence mean of mCardinal signal (excitation 605 nm, emission 659 nm) was normalized by the cell density (OD₆₀₀). Error bars are ± S.D., n = 3