Figure 1.

Protein purification schematic for (a) conventional affinity-base purification (pMAL), (b) intein-based affinity purification where the linker between the affinity tag and the target protein is replaced by a self-cleaving intein, (c) PHB-intein mediated protein purification where in vivo PHB granules substitute for the affinity resin, and (d) ELP-intein mediated protein purification where an in vivo temperature sensitive, self-cleaving tag replaces both the affinity resin and the affinity tag. † Scanning electron micrograph image of PHB granules expression in E. coli was taken from Reference [20].