Fig. 4.

Shrinkage occurs during stationary phase and is exacerbated by intermediate levels of glucose. (A) Stationary-phase KC1193 cells exhibited a large periplasmic region that decreased in area over several hours after the cells were incubated in fresh LB. (B) The periplasmic area in ∆rpoS and ∆cyaA cells expressing periplasmic mCherry decreased to zero slower and faster, respectively, than in wild-type cells, consistent with their differences in lag time (Inset). To account for different cell sizes, the periplasmic areas in each strain were normalized to the corresponding periplasmic area at t = 0. The data points are mean ± SEM with n > 100 single cells. Inset: lag times of each strain. The data points are mean ± SD with n = 8 replicates. (C–E) Cells grown in LB+0.2 to 0.3% glucose exhibited larger periplasmic spaces than cells grown in LB or LB+2% glucose. The images in (C) are of KC1193 cells. The total periplasmic area (D) and the periplasmic area normalized to total cell area (E) were highest in LB+0.2 to 0.3% glucose. n > 100 cells for each condition.