FIG. 8.

Failure of unactivated p-coumarate to elicit expression of hcaE::lacZ or hcaB::lacZ in strains impaired in hydroxycinnamate:CoASH ligase. Succinate-grown cells were amended with p-coumarate as noted. LacZ levels for the two constitutive strains with the ΔhcaR1 mutation provide the respective values to be expected for induced cells analogous to what was seen with ADP8110 and ADP8117 cells in Fig. 5. Promoter activity was measured, and the averages of three independent trials are shown with their standard deviations.