Recent Developments in Enzyme Isolation Processes

Abstract

Studies leading to a process for the continuous isolation of enzymes have been described and the arguments for and against continuous operation summarized (1). A process for production of β-galactosidase from E. coli has subsequently been described (2) in which 100 g/hr of 10% pure β-galactosidase is produced as an ammonium sulfate precipitate. Additional studies have now been made of batch affinity chromatography for completion of the purification. These were based on the factors affecting large-scale chromatography (3) and on a study of specific factors affecting scale-up of the affinity chromatography of β-galactosidase (4). The complete pilot scale chromatography study will be described shortly (5). The capacity of the 1.8 liter column was 3 × 10⁶I.U. of β-galactosidase, with 95% binding efficiency. This corresponds to a load of 35g of protein applied and gives about 3.6 g of essentially pure enzyme in a single 2 hour cycle of loading, washing off contaminant and eluting purified enzyme. The completion of the pilot scale affinity chromatography work will permit the establishment of a complete continuous flow process for production of β-galactosidase. The final step will be operated either as an automatic batch method with pulses of material added at intervals or as a continuous chromatographic step using the device previously described (1).