FIG. 3.

CpxR affects the level of expression of three icm::lacZ fusions. The level of expression of nine icm::lacZ fusions (icmT, icmR, icmQ, icmP, icmM, icmJ, icmF, icmV, and icmW) was examined in the L. pneumophila wild-type strain JR32 (white) and the cpxR insertion mutant OG2002 (gray). The β-galactosidase activity was measured as described in Materials and Methods. Four icm::lacZ fusions that had high β-galactosidase activities (A) and five that had low activities (B) are shown. The data are presented as averages of results of at least three different experiments. The error bars represent standard deviations. The level of expression of the vector was 7.3 ± 2.4 MU.