Fig 3. Accumulation of Hoechst 33342 (HT) in Escherichia coli.

(a). Time courses of Hoechst accumulation (±SD; n = 4) in WT and WT-Pore cells grown without and with 0.1% arabinose to induce the expression of the pore. The data were fit to a burst- single exponential decay, I = A1 + A2∙(1-exp(-k₂t)), where A1 describes the fast initial step, and the slow step reflects subsequent rise in fluorescence (see Methods for details). Arrow marks the moment when cells were mixed with 4 μM Hoechst (b). Fluorescence microscopy analysis of Hoechst uptake by WT and WT-Pore cells grown with 0.1% arabinose, following incubation with 1 μM Hoechst for 1 min. (c). Initial rates of Hoechst accumulation in WT and WT-Pore cells grown with 0.1% arabinose during the slow phase shown in panel a and S4 Fig. The data were fit to Eq 5. (d). Steady state concentrations of Hoechst in the cytoplasm fit to Eq 4. (e). Steady state concentrations of Hoechst in the periplasm.