LARGE-SCALE GEL-FILTRATION IN PURIFICATION OF HUMAN LIVER AND SMALL INTESTINE ALKALINE PHOSPHATASES

The alkaline phosphatases of human liver and small intestine have been purified 2000 and 1000 times, respectively, which is higher than previously reported for any human alkaline phosphatase. The enzyme preparations are still contaminated with a hemoprotein. The purification scheme includes gel filtration of a sample of about 100 ml on large columns designed especially for use with weak gels such as Sephadex G-200, and a modified recycling gel filtration technique which eliminates the danger of overtaking. The molecular weights of the human phosphatases are about 200,000. Each enzyme is homogeneous on gel filtration, and heterogeneous on anion-exchange chromatography and starch-gel electrophoresis. © 1968.