Cause of Irreversible Inactivation of Aminoacylase in Urea Solution

Some have suggested that the refolding of denatured aminoacylase is difficult.The present study reports that aminoacylase denatured in urea concentrations more than 4 mol/L was markedly but partially unfolded and could be reactivated and refolded very rapidly.However, the extent of reactivation decreased with increasing time suggesting an irreversible inactivation occurred in a biphasic course.The fast phase of the irreversible inactivation is suggested to accompany the unfolding.Oxidation of the thiol groups exposed by unfolding may be one of the main causes of the second phase of the irreversible inactivation.