Figure 3. Solubility and expression efficiency of fused gene constructs.

Eighty seven fusion partner genes were combinatorially fused to three different genes (hBD2, hEGF, hEPO) using three-step PCR. All PCR products coding each fused gene were directly used as expression templates for cell-free protein synthesis where expression efficiency and solubility were measured. After 3 h for cell-free expression, the reaction samples were centrifuged at 10,000 rpm for 30 min. Both pellet and soluble fractions were analyzed by radioactivity counting. The degree of solubility and expression yield enhancement for each fusion gene is colorized with red and blue respectively.