REACTIVATION OF DENATURED CITRATE SYNTHASE

1. The imported mitochondrial enzyme citrate synthase can be partially (less-than-or-equal-to 45%) reactivated after denaturation in guanidi nium chloride, if the concentration of the denaturing agent is lowered by dialysis, rather than by dilution, when essentially no reactivatio n is observed. 2. The presence of a reducing agent (dithiothreitol) is necessary for regain of activity. 3. Optimum regain of activity occur s at enzyme concentrations of about 10-20-mu-g/ml; at higher concentra tions there is significant formation of aggregates.