SELECTIVE SEPARATION PROCESS OF PROTEINS BASED ON THE HEAT STRESS-INDUCED TRANSLOCATION ACROSS PHOSPHOLIPID-MEMBRANES

Heating of several protein solutions at 40-47 degrees C for 5-60 min i n the presence of 1-palmitoyl-2-oleoyI-sn-glycero-3-phosphocholine (PO PC) liposomes induced the translocation of beta-galactosidase (beta-ga l), alpha-glucosidase (alpha-glu) and bovine carbonic anhydrase (CAB) from outer to inner aqueous phase across the liposome membrane. The tr anslocated amounts of P-gal at various temperatures were maximized und er suitable heating conditions (45 degrees C, 30 min). Those of alpha- glu and CAB were maximized at 40-45 and 60 degrees C, respectively. Ea ch maximum value could be correlated with the corresponding local hydr ophobicity of each protein evaluated by the aqueous two-phase partitio ning method. The possibility to apply these heat-induced translocation phenomena to the bioseparation of proteins was successfully demonstra ted for the model mixture solution of P-gal, a-glu and CAB. (C) 1998 E lsevier Science B.V. All rights reserved.