Abstract: Recently the refolding studies have been concentrated on alkaline phosphatase from E. Coli. The present experiments studied the refolding of mammalian enzyme. Calf intestinal alkaline phosphatase (CIP) was denatured in 3 mol/Lguanidine hydrochloride solutions for 2 h at 25 ℃. Under suitable renaturation conditions, the kinetic courses of enzymatic activity recovery were investigated in the absence and presence of magnesium ions at 2 mmol/Lconcentration, and compared to each other. The two remarkably different courses characterized by the final values of activity recovery, recovery levels, kinetic constants of activity recovery and relative standard deviation of the data indicated that magnesium ions behaved like "site-specific" effectors which were bound to the concerning residues of enzyme protein and stabilized the conformation of active site domain, thus guided the refolding process in a productive pathway.

Key words: alkaline phosphatase, refolding, magnesium