Fig. 3: Cellular growth and survival scale with activation efficiency of LpoB variants.

a Growth curves under non-permissive growth conditions (½ LB 0 NaCl 42 oC) of ∆ponA Para::ponA ∆lpoB negative control (black), ∆ponA Para::ponA ∆lpoB Plac::lpoB WT (grey) or engineered LpoB variants (red). Averages of three technical replicates are shown as lines, with standard deviation depicted as a shaded region. In the absence of induction, strains of higher affinity variants that retain the ability to activate PBP1b exhibit modestly faster growth than the WT strains. Strains of LpoB mutants that disrupt binding to PBP1b (E201R) or enzymatic activation (Y178W) fail to grow. b Titer experiments with strains from (a). Overnight cultures were serially diluted and spotted on LB agar with either 0.2% arabinose, 0.2% glucose, 25 μM IPTG or 100 μM IPTG. Data shown in (a, b) are representative of three biological replicates.