Direct process integration of cell disruption and fluidised bed adsorption for the recovery of intracellular proteins 1

An integrated process for the primary capture of an intracellular enzyme, where cell disruption is directly coupled with ýuidised bed adsorption of the product, was proposed as a generic approach to beneüt the yield and molecular integrity of labile protein products. The puriücation of glyceraldehyde 3-phophate dehydrogenase (G3PDH) from waste brewers’ yeast was selected for the demonstration of this principle. Cell disruption by bead milling was combined with direct adsorption of the enzyme on a Cibacron Blue derivative of a kieselguhr–agarose composite adsorbent in a ýuidised bed contactor operated immediately downstream of the cell disrupter. The short process time and immediate sequestration of product from the hostile disruptate environment facilitated the recovery of partially puriüed preparations of this labile enzyme from yeast aged at Ô20ÄC for 9 months. The recovered speciüc activity of 7.6 IU mg—1 bettered that expected from the extended time-scale of sequential batch operations of milling, centrifugation or microültration, and üxed bed chromatography. The potential role for this novel approach to process integration is discussed in the context of the adsorbent and contactor optimisation necessary to establish efficient, continuous primary recovery of labile intracellular proteins. 1999 Society of Chemical Industry (