FIGURE 3:

Kinetics of growth and predicted growth rate response in cultures transiently relieved from nitrogen limitation. Ammonium-limited chemostat cultures grown at 0.12 h⁻¹ were subjected to an instantaneous addition of (A) 400 μM glutamine, (B) 40 μM glutamine, (C) 800 μM proline, or (D) 80 μM proline. For each perturbation experiment, we modeled the change in growth rate as a continuous function of time (blue line). We measured culture density at discrete times points (blue points) and predicted the instantaneous growth rate on the basis of global gene expression (red points).