Simple protein purification through affinity adsorption on regenerated amorphous cellulose followed by intein self-cleavage

A simple, low-cost, and scalable protein purification method was developed by using a biodegradable regenerated amorphous cellulose (RAC) with a binding capacity of up to 365 mg protein per gram of RAC. The recombinant protein with a cellulose-binding module (CBM) tag can be specifically adsorbed by RAC. In order to avoid using costly protease and simplify purification process, a self-cleavage intein was introduced between CBM and target protein. The cleaved target protein can be liberated from the surface of RAC by intein self-cleavage occurring through a pH change from 8.0 to 6.5. Four recombinant proteins (green fluorescence protein, phosphoglucomutase, cellobiose phosphorylase, and glucan phosphorylase) have been purified successfully.