FIG. 7.

Effect of mutations in the GpsB C-terminus on growth of L. monocytogenes at 42°C. (A) L. monocytogenes strains EGD-e (wt), LMJR19 (ΔgpsB), LMS56 (ΔgpsB+gpsB), LMS185 (ΔgpsB+gpsBF91A), LMS186 (ΔgpsB+gpsBL94A), and LMS187 (ΔgpsB+gpsBF105A) were grown in BHI broth containing 1 mM IPTG at 42°C, and growth was recorded in hourly intervals. (B) Growth of L. monocytogenes strains EGD-e (wt), LMJR19 (ΔgpsB), LMS56 (ΔgpsB+gpsB), LMJR161 (ΔgpsB+gpsBT88A), and LMJR162 (ΔgpsB+gpsBT88D) was measured as described in (A). All average values and standard deviations were calculated from experiments performed in triplicate. (C) Western blots showing expression of LmGpsB proteins in the same set of strains as in (A, B) during growth at 37°C (top panel). Cells were harvested for protein isolation at an optical density of 1.0 (λ = 600 nm). A parallel Western blot shows DivIVA expression for control (bottom panel). (D) Stability of LmGpsB proteins after temperature upshift to 42°C. Western blot showing amounts of LmGpsB proteins in cells that were grown at 37°C to an optical density of 1.0 and then shifted to 42°C for 2 further hours before protein isolation (top panel). Again, a parallel Western blot shows DivIVA protein levels for control (bottom panel).