Fig. 6: Experimental validation of the Egos circuit.
a Schematic of the in vivo Egos circuit. FmdA was placed downstream of a DOD-mCherry fusion with an RBS library to couple DOD expression noise with ammonium availability. b RBS sequences and their corresponding translation initiation rates65 of the four Egos variants. c, d Representative single-cell fluorescence microscopy images with 1 μm scale bar showing mCherry and betaxanthin levels for the open-loop control and each Egos variant. e, f Probability density distributions of protein (mCherry) and metabolite (betaxanthin) concentrations calculated from fluorescent microscopy. g Growth curves of Egos variants and the open-loop control (lacking fmdA) in formamide-based selective medium. h Quantification of total betaxanthin titer. Data represents the mean ± s.d. of biological replicates (n = 3). ** indicates p ≤ 0.01 (p = 0.0073 for Egos4), and *** indicates p ≤ 0.001 (p = 0.00039 for Egos2 and p = 0.00027 for Egos3) from two-tailed t-test. Source data are provided as a Source Data file.
