Figure 1

Global gene expression profiling during the growth time course. Panel A) Graphic representation of how the cellular pellet weight increases along the time course in a sigmoidal way. Panel B) Graphic representation of how the erythromycin concentration increases along the time course. Panel C) Visualization by dChip of the 404 genes, selected by a q-value <= 0.001, and determining a hierarchical clustering of the samples (Red = up-regulation; Green = down-regulation); on the right side of the figure, two columns respectively show the functional classification of the 404 genes whose transcription profile is visualized and their positional distribution in the core (dark blue) and non core region (light blue) of the genome. The transition from phases A, B and C are evidenced by dotted lines (Phase A: rapid growth lasting until 32 h; Phase B: brief period of growth slowdown lasting until 52 h; Phase C: after 4 hours cultures resume another rapid growth phase from 56 to 72 h before entering the stationary phase).