PREDICTING THE PARTITION-COEFFICIENTS OF A RECOMBINANT CUTINASE IN POLYETHYLENE-GLYCOL PHOSPHATE AQUEOUS 2-PHASE SYSTEMS

A model for the prediction of protein partition coefficients in aqueou s two-phase systems has been developed. This model accounts for both c harge-independent and electrostatic effects. The determination of none lectrostatic effects was based on the model of Eiteman and Gainer for uncharged solutes while the electrostatic contribution was computed us ing TITRA, a program that uses a continuum electrostatic model to trea t charge interactions in proteins and considers the effect of pH and i onic strength. The partition coefficients of Fusarium solani pisi reco mbinant cutinase have been satisfactorily predicted in polyethylene gl ycol (PEG) 1000 and phosphate aqueous two-phase systems at a pH range of 6.0-9.0 The model failed to predict the enzyme partitioning behavio r at pH 4.5. (C) 1997 John Wiley & Sons, Inc.