Fig. 1.

Growth curves of Escherichia coli strain BL21/pMINOR2 under different conditions. (A) Growth curve of a culture of E. coli grown in 0.5 l of 2× YT medium in a 2-l flask at 30 °C with shaking. The doubling time in the mid-log phase was 52 min. (B) Growth curves of two cultures of E. coli grown in 20 l of 2× YT medium in a 30-l fermentor at 30 °C. Optical density of the culture at 600 nm (OD₆₀₀) and concentration of dissolved oxygen (DO) are shown as circles and triangles, respectively. The doubling times in the mid-log phase of the two cultures were 57 min (open circles) and 48 min (filled circles). (C) Growth curves of three cultures of E. coli grown in 20 l of 2× YT in a 30-l fermentor at 25 °C. The doubling times in the mid-log phase of the three cultures (open, closed and gray circles) were all ∼70 min.