A monoisozymic nucleoside diphosphate kinase capable of complete phosphorylation

Nucleoside diphosphate kinase (EC 2.7.4.6) has been purified nearly 2000-fold from beef brain particulate material in 65% yield. The purification procedure described here takes advantage of the relatively unique complexation of the enzyme with blue dextran-Sepharose in the presence of a nonionic detergent. Unlike preparations of the enzyme previously described, the bovine brain enzyme is monoisozymic and each polypeptide chain can be phosphorylated by a nucleoside triphosphate substrate. Catalytically functional forms of the enzyme having lower pI values can be generated by proteolysis.