Purification of nucleosidediphosphatase of rat liver by metal-chelate affinity chromatography

A procedure is presented for the purification of nucleosidediphosphatase (nucleosidediphosphate phosphohydrolase, EC 3.6.1.6) of rat liver by affinity chromatography using metal conjugated to epoxy-activated Sepharose 6B. The enzyme is eluted from the conjugate by a solution of L-histidine. The enzyme, when bound to metal-chelate gel, is active in a suspended form, suggesting that the catalytic site is different from the site that binds to the metal-chelate gels. Substrate specificity and Km value of the enzyme obtained are similar to those of the enzyme obtained from the same sources by a conventional procedure, indicating that the metal-chelate affinity chromatography does not bring about any substantial change in the catalytic properties.