Bacteriophage T5 promoter for E. coli RNA polymerase, with embedded lac operator.
Figure 1. The relative fluorescence intensity of EGFP with T5 promoter measured by 96-well plate reader EGFP with T5 promoter represents the relative fluorescence intensity of BL21(DE3) transformed with plasmid encoding EGFP protein. The Negative represents the relative fluorescence intensity of BL21(DE3) transformed with plasmid encoding nonsense mutated EGFP protein. Significant difference between them shows that EGFP can be expressed and function well inside E.coli cells.