Purification and characterization of alkaline phosphatase from cultured rat ascites hepatoma cells

Alkaline phosphatase of cultured rat ascites hepatoma cells has been purified by butanol extraction, DEAE-cellulose column chromatography, gel filtration through Sephadex G-200, concanavalin A-Sepharose affinity chromatography, and polyacrylamide gel electrophoresis. Affinity chromatography confirmed the glycoprotein nature of alkaline phosphatase from cultured rat ascites hepatoma cells. Electrophoresis on polyacrylamide gels of various concentrations indicated a molecular weight of 290,000. The molecular weight of the subunit was estimated to be 72,000 by SDS-polyacrylamide gel electrophoresis. These findings suggest that alkaline phosphatase of cultured rat ascites hepatoma cells is a tetramer with a subunit molecular weight of 72,000.