Fig 4. Pseudomonas exotoxin (PE) productions using the S30-T7 CFPS system originated from two different E. coli strains (BL21 and MRE600).

Reactions were performed with and without the presence of DNA template. (A) Western blot analysis of cell-free reactions demonstrated the production of PE ~ 66 kDa. Purified PE served as positive control (described in Appendix F in S1 File.). Arrows indicate the position of PE bands. (B) The therapeutic potency of PE was evaluated on 4T1 cell-line. The viability of the cells was determined by MTT assay. Cell viability values obtained without the presence of purified PE or DNA were set as 100%, and the other values were normalized according to them (error bars represent standard deviation from at least three independent samples).