FIG. 4.

Growth, lactic acid production, fluxes, and relative fluxes for MBP71 and derivatives with ATPase activity. Stationary-phase cultures of MBP71, MBP89 (low activity), MBP90 (medium activity), and MBP98 (high activity) were inoculated at an OD₆₀₀ of 0.3 AU into 200 ml of fresh LM17 (erythromycin was not added, since it is not required for plasmid stability in the nonreplicating cells). MBP71 was also inoculated at an OD₆₀₀ of 0.03 AU into LM17 containing thymidine (dT). OD₆₀₀ and pH were monitored over time. (A) OD₆₀₀. When thymidine was added to the MBP71 culture, the specific growth rate was 1.03 h⁻¹. The curves connecting the points are sixth-order polynomial fits. (B) Lactic acid produced. (C) Lactic acid flux. (D) Fluxes from panel C relative to the MBP71 culture. Only data points at which the OD₆₀₀ was less than 1.0 and the pH was more than 5.8 are shown.