Purification of native and modified enzymes using a reactive aqueous two-phase system

We describe the purification of native and modified enzymes using a reactive aqueous two-phase systems. The two-phase systems consist of a hydrophilic AKM copolymer and dextran. Cellulase was modified with the AKM copolymer; the degree of modification is directly proportional to the number of maleic acid anhydride groups present in the AKM copolymer. Partitioning of the native and modified cellulases was also investigated in the aqueous two-phase AKM copolymer/dextran systems; the partition coefficient increases as the degree of modification in creases. The AKM-0531 copolymer is enzyme selective; the modified enzyme always shows separation that is better than that of the native enzyme.