Figure 2.

A schematic illustration for PhaR based protein purification system. Fusion proteins of PhaR, intein and a target protein were expressed in E. coli BL21 (DE3), the cellular supernatant obtained after sonication and centrifugation contained all crude proteins that were subjected to incubation with PHBHHx nanoparticles. After the overnight incubation at 4°C, the pellets were harvested and washed to remove unbound proteins. Subsequently, cleavage buffer was used to trigger self-cleavage of intein at 25°C. The target protein was released into the supernatant and separated from the pellets by centrifugation after cleavage incubation.