Fig. 4.

Real-time measurements of fluorescence intensity (A) and OD₆₀₀ (B) of the mutants during the whole process of continuous evolution. The process was performed in two stages, in which the best-characterized mutant from the first phase (0–380 ​h) was forced to the second phase of continuous evolution (381–550 ​h) for further evolution. The data points in (A) marked with open triangles or squares indicate that samples at those time points were selected for off-line characterization. The data points in (B) labeled with arrows indicate the time points for introduction of 0.1% w/v L-arabinose for induction.