Purification of Rabbit Liver Fructose 1, 6-Diphosphatase by Substrate Elution

A procedure is presented for the large scale preparation of homogeneous rabbit liver fructose 1,6-diphosphatase. Essential steps include the batchwise adsorption of enzyme from crude dialyzed liver supernatant on carboxymethylcellulose at pH 6, followed by elution with 0.06 mm fructose 1, 6-diphosphate at pH 6.8. A 300- to 500-fold increase in specific activity was obtained in this latter step. A more generalized procedure for enzyme elution by substrate is also described which involves the use of a concave salt gradient containing substrate.