FIG 4.

Mutation frequency analyses. (A) Analysis of A-to-C (or T-to-G) mutation frequency of the CC101 ΔmutT::kan strain harboring the pBAD vector or its derivatives expressing EcoMutT or EcoNDK (refer to Table S3). Reversion frequencies (using 9 or 10 replicates for each strain) were calculated by dividing the number of colonies that appeared on the minimal medium Amp plate containing lactose by the corresponding CFU on the minimal medium Amp plate containing glucose. (B) The expression of plasmid-borne EcoMutT or EcoNDK in the CC101 ΔmutT::kan strain was confirmed during the assay conditions.