Figure 2.

Regulation of AimB expression is critical for rapid C. crescentus growth. (A) AimB overexpression inhibited growth as measured by optical density. Cells containing either the empty vector (pBXMCS-2) or an AimB overexpression vector were grown with 0.03% xylose (induced) or 0.3% glucose (uninduced). (B) AimB overexpression was toxic to cells as measured by colony forming units (CFUs). Samples were removed every 2 h from the cultures in (A) and plated to measure CFUs. (C and D) AimB overexpression and A22 treatment synergistically resulted in toxicity as measured by optical density (C) and CFUs (D). In (C), cells containing either pBXMCS-2 or an AimB overexpression vector were grown in the presence of 0.03% xylose and either 10 μg/mL A22 or methanol (MeOH). Samples were removed every 2 h from the cultures in (C) and plated to measure CFUs (D). (E) Depletion of aimB messenger RNA using CRISPRi did not affect population growth as measured by optical density. dCas9 expression was induced with 0.5 mM vanillate in cells harboring either a control plasmid (psgRNA-base) or sgRNA-aimB (n = 2 biological replicates, each with three technical replicates; error bars are SEM). (F) The rate of width increase for cells grown on peptone yeast extract agarose pads containing 2.5 μg/mL A22 and 0.5 mM vanillate was higher in cells depleted for AimB than in wild-type cells (n > 24 cells per strain at each timepoint; error bars are SEM; error in slopes is the standard error of regression). To see this figure in color, go online.