FIG. 6.
β-Galactosidase activity in wild-type (WT, χ3761), Δlrp (χ9411), and lrp(Con) (χ9448) strains containing PhilA-lacZ, PinvF-lacZ, PssrA-lacZ, or PmurA-lacZ promoter fusions. Bacterial cells were grown in LB broth to mid-exponential phase and assayed for β-galactosidase activity (69). The PmurA-lacZ fusion was used as the negative control. Data are the means ± the standard errors of two independent experiments. *, Significantly different from the wild-type strain χ3761 (P < 0.05). N.S., not significant.