Figure 1. Deletion mutations can affect the growth of Escherichia coli, and the production of light from bacterial luciferase.

E. coli Keio strains, and the parental BW25113 strain, were transformed with a bacterial luciferase expression vector (pIMBB-T5-lux). The transformants were shaken in minimal medium at 37°C for 48 hours; the optical density at 600 nm (green or blue) and luminescence (red) were recorded every 30 minutes. Data from the (A) parental lux/BW25113 control, and three representative Keio transformants, (B) lux/ΔybhC, (C) lux/Δlon and (D) lux/Δfiu, are presented here. The growth curves of the three Keio strains differ from that of the BW25113 control, but the luminescence curves are all similar in shape.