FIG 7.

CpxR is required for Lp to survive a thermal stress. The WT, cpxR mutant (ΔcpxR), cpxR mutant with the empty vector (ΔcpxR + pMMB207c), and complemented strain (ΔcpxR + pcpxR) were suspended in Fraquil for 24 h and then subjected to thermal stress at 55°C. The survival of the strains was measured by CFU counts every 15 min from 0 to 60 min. The data shown represent the average of three independent replicate with standard deviation. A two-way ANOVA with a Tukey correction for multiple comparison was used to determine if the results were significantly different. The statistical difference shown in Fig. 7 compares the WT and tsp mutant; ***, P < 0.005.