Fig. 2

Directed evolution of three new riboswitches. a Each new riboswitch was cloned into rClone Red and grown in triplicate over 10 h with one of three treatments as indicated. Each population was measured for RFP and cell density three times to produce an average end point value ± s.e.m. b Theophylline-induction values from three independent populations from a were normalized by comparing each construct to the fold induction of RS-C in the absence of theophylline. Error bars represent s.e.m