FIG 1.

Overexpression of the periplasmic reductase DsbG suppresses the ΔelyC mutant lysis phenotype. (A) Screening for ΔelyC genetic suppressors with the CPRG assay. Cells from the E. coli wild-type strain MG1655 (WT), its ΔelyC mutant (strain EM9), and the ΔelyC mutant carrying a multicopy plasmid containing the indicated gene were patched onto LB agar supplemented with CPRG (20 μg/ml) and IPTG (100 μM) and were grown overnight at 21°C. (B) Testing the specificity of the DsbG suppression effect with the CPRG assay. ΔmrcB mutant (strain MM39) cells with or without a multicopy plasmid carrying the mrcB or dsbG gene were grown on a CPRG plate and were incubated overnight at 21°C. (C) Testing the DsbG suppression effect in LB liquid medium. Shown are growth curves of WT cells, ΔelyC cells, and ΔelyC cells with a plasmid carrying dsbG. The experiment was performed in triplicate. Data points and error bars represent average values and standard errors, respectively.