[Reactivation of denatured lysozyme with immobilized molecular chaperones GroE]

The molecular chaperones GroEL and GroES were expressed in recombinant E. coli and purified by anion exchange chromatography. The renaturation of the denatured lysozyme with the free and immobilized GroEL/ES or GroEL was studied. We show here that using free GroEL alone could reactive the denatured lysozyme up to a relative activity of over 90%. The immobilized GroEL was also effective for promoting lysozyme refolding. Moreover, the optimal temperature (i.e., 37 degrees C) and (pH(i.e., 6 to 8) for the immobilizde GroEL-facilitated lysozyme refolding operation were determined. Under the optimal condition, the activity of lysozyme could be recovered up to 85%. In addition, the immobilized GroEL was repeatedly used five times without loss of its renaturation ability, indicating its potentiality to be used in practical downstream bioprocesses.