Fig. 3.

Retention of induction response in E. coli ELMs. a) Schematic of dynamic induction cycles. Alternating delay (gray) and induction (green) and cycles were implemented by placing the ELMs into fresh media every 24 ​h. Varying delay lengths were applied to the first delay cycle (Delay 1). b) Retention of induction response following a subsequent induction cycle. Subplots (top to bottom): Delay 1 ​= ​no-delay, 1 day, 2-days, with uninduced, no aTc controls (Supplementary Fig. S5b) replotted on each subplot. Full expression capacity is defined as the maximum expression level achieved during Induction 1. Retained expression capacity and non-baseline returns for each Delay 1 length were calculated relative to the full expression capacity. Plotted values represent the mean ​± ​standard deviation from n ​= ​5 technical replicates, except for uninduced∗∗ samples (∗∗n ​= ​2 technical replicates). Green and gray shades denote induction and delay periods, respectively. Statistical significance in sfGFP fluorescence at two consecutive time points was evaluated using a two-tailed unpaired Student's t-test (p ​> ​0.05). (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)