Fig. 5: DnaK decreases dormancy and is important for regrowth. | Nature Communications

Fig. 5: DnaK decreases dormancy and is important for regrowth.

From: Composition and liquid-to-solid maturation of protein aggregates contribute to bacterial dormancy development and recovery

Fig. 5

Aggregation, persistence and VBNC cell formation were measured for E. coli WT, E. coli ΔdnaK (a-d), E. coli pBAD33Gm (Vector), and E. coli pBAD33Gm-dnaK (DnaK) (e–h). a, e Quantitative analysis of microscopy images shows the fraction of cells containing Ph aggregates. Data are represented as averages ± SEM, (n ≥ 3, > 50 cells analyzed for every repeat) (Supplementary Tables 2-4 and 9-12 for exact values). b, f Persistence was measured at different time points. Data are represented as averages ± SEM, (n ≥ 4) (Supplementary Tables 2-4 and 9-12 for exact values). c, d, g, h The number of CFUs (solid line) and viable cells (dashed line) were measured at different time points. The area between both curves represents the number of VBNC cells. Data are represented as averages ± SEM, (n ≥ 4) (See Supplementary Tables 2-4 and 9-12 for exact values). Note that viable cells and CFUs are measured differently and are therefore not perfectly comparable. The discrepancy observed at some early timepoints suggests that the number of viable cells may be underestimated. i The number of CFUs and viable cells was determined after 72 hours of obgE overexpression in WT and deletion strains. The logarithm of the number of viable and culturable cells was compared between WT and deletion strains using a two-way ANOVA with Dunnett’s correction for multiple comparisons (ΔdnaK: q ratio = 9.771, 42 degrees of freedom, ****P < 0.0001). Bar graphs and error bars represent averages ± SEM, (n ≥ 3) (See Supplementary Table 13 for exact values). j The percentage of proteins that are aggregated after 40 hours of incubation and that are a substrate of DnaK was calculated64. Bar graphs and error bars represent averages ± SEM, (n = 3, with n the number of samples per strain from which the aggregates were purified). For WT, ΔrpoS, ΔsdhC, ΔrecA, Vector and ObgE strains, the mean ± SEM values are 43.56 ± 2.123, 42.27 ± 0.5844, 44.07 ± 1.067, 44.55 ± 1.785, 42.59 ± 0.4752 and 48.01 ± 0.5392. Source data are provided as a Source Data file.

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