FIG 5.

The deletion of hilE reverses the repression of hilA in a constitutive phoB-expressing strain. The wild-type strain is S. enterica serovar Typhimurium SL1344. RL291 is an SL1344 derivative that contains a pstS mutation. BJ3100 is an RL291 strain containing a defined hilE::cam mutation within the chromosome. Each strain contained the hilA::lacZY reporter pLS31. The strains were grown in LB overnight with shaking, and expression levels were determined by measuring lacZ output as measured by β-galactosidase activity.