Figure 1
UPEC growth in the presence of PMBN increases cell electrocompetence in a reversible and dose dependent manner. (a) Representative plate images comparing the yield of pSU2718 plasmid electrotransformants of UPEC strain CFT073 grown without (Nil) or with PMBN (6 µg/ml) prior to electroporation. (b) Transformation frequency, (c) survival rate after electroporation, and (d) transformation efficiency of CFT073 grown with different concentrations of PMBN. (e) Chemical transformation frequency of CFT073 grown in the absence (Nil) or presence of PMBN (6 µg/ml). (f) Electrotransformation frequency of CFT073 grown in the presence of PMBN (4 µg/ml) and then sub-cultured into media devoid of PMBN prior to electroporation (Recover). (g) Electrotransformation frequency of CFT073 grown to OD600 ~ 0.7 and subsequently incubated without (Nil) or with PMBN (1 µg/ml) for 10 min before harvesting and electroporation. Electrotransformation frequency of UPEC strains UTI89 (h) and EC958 (i) grown without or with different concentrations of PMBN. In all experiments, the starting competent cell density was the same between groups. Data from three independent experiments are shown with bars denoting the group mean and error bars the standard error of the mean (mean ± SEM). Tfs transformants.
