FIG. 3.

Expression from the P_yydF and P_yydI promoters. Expression levels of the P_yydF-lacZ fusion (A and C) and P_yydI-lacZ fusion (B and D) are shown. (A and B) Expression during growth in different media: rich medium (LB; black bars), sporulation medium (DSM; white bars), and MC medium (gray bars). (C and D) Expression from these promoters in the wild type (black bars) and abrB (white bars) and rok (gray bars) mutants grown in LB medium. Note that T₀ corresponds to the transition from logarithmic growth to stationary phase. Each experiment was repeated at least twice, and a representative assay is shown here. Error bars represent standard deviations between triplicate β-galactosidase assays.