Studies on bovine-liver alkaline phosphatase, purification, phosphate incorporation

Abstract

• 1.

  1. A highly purified preparation of bovine-liver alkaline phosphatase (ortho-phosphoric monoester phosphohydrolase, EC 3.I.3.I) has been obtained from a liver homogenate treated with butanol. Acetone and ethanol fractionation have been used, followed by two consecutive chromatographies on TEAE-cellulose and one on Sephadex G-200.

• 2.

  2. Labelled phosphorylserine has been isolated from acid hydrolysates of the purified enzyme, which had been incubated with radioactive orthophosphate and then inactivated by acid. Most probably, the phosphate was bound to a particular serine molecule at the active site of the enzyme. This supports the view that an intermediate phosphorylenzyme is formed during the action of alkaline phosphatase.