FIG. 3.

Phenotypic analysis of the phoP mutation in P. luminescens. (A) Growth curves for P. luminescens wild-type strain TT01, phoP knockout mutant PL2104, and complemented phoP mutant PL2104(pDIA607) grown in ED* synthetic medium containing 10 mM MgCl₂ (solid symbols) or 20 μM MgCl₂ (open symbols). OD600nm, optical density at 600 nm. (B) Motility of the P. luminescens TT01 and PL2104 strains on semisolid (0.3% [wt/vol] agar) medium plates. Plates were incubated for 15 to 24 h at 30°C. (C) Mortality of S. littoralis infected with the P. luminescens wild-type strain, phoP knockout mutant, and complemented phoP mutant. Bacteria obtained at the end of the exponential phase were injected into fourth-instar larvae. The mortality values are based on data obtained after injection into 20 larvae. All experiments were repeated at least three times.