Fig. 4. Combining the T7p^CONS and TIR variants increases production efficiency.

a Schematic of the pET28a transcription and translation initiation region. In a standard production experiment, the coding sequence for the protein of interest is inserted in frame with the His₆-tag and thrombin protease site (His₆-TPS). b Engineering the T7p^CONS in combination with either TIR-1 or TIR-2 resulted in an improvement in protein production. For sfGFP a maximal 121-fold increase was observable relative to the standard pET28a (left panel). sfGFP is the major protein constituent when T7p^CONS and TIR-2 are combined (right panel). c, d. MTH1 and Neil3 production is enhanced by the addition of the combined TIR-2 and T7p^CONS. Data are presented as mean ± s.d. (n = 3). A statistically significant difference of p < 0.05, p < 0.01 or p < 0.001 relative to pET28a (two-tailed Student’s t test) is denoted by *, ** and ***, respectively.