Effects of eution conditions of the separation of calpastatin, mu- and m-calpain on DEAE-Sephacel chromatography

A rapid stepwise measurement for the activities of calpastatin and mu- and m-calpains was developed by using 2-stage elution at pH 8.5 and then 7.0. T he activities of calpastatin, mu-calpain and m-calpain can be rapidly assay ed following the separation on DEAE-Sephacel chromatography by a 2 stage el ution with 90 mM NaCl (pH 8.5), and then by 200 and 300 mM NaCl in elution buffer (pH 7.0). No significant differences in the recovery of these protei nases and inhibitor was observed between stepwise gradient and linear gradi ent methods.