FIG. 8.
Differences in the levels of transcription from the phz promoters of strains 2-79 and 30-84 are independent of the source of the PhzR proteins. Reporter strains harboring phzX::lacZ or phzA::lacZ fusion plasmids together with functional copies of noncognate phzR were incubated with increasing concentrations of N-(3-OH-hexanoyl)-l-HSL (•), N-(hexanoyl)-l-HSL (▪), or N-(3-OH-octanoyl)-l-HSL (▴) for 3 h in ABM. Following incubation, the cells were assayed for β-galactosidase activity, expressed as Miller units. (A) Reporter strain harboring pSF110 (PhzR30-84) and pSF107 (phzA::lacZ); (B) reporter strain harboring pSF105 (PhzR2-79) and pSF116 (phzX::lacZ). The experiment was repeated three times, and the mean values of all repetitions together with the standard errors are shown in the plots.