Tetrose diphosphate, a specific inhibitor of glyceraldehyde 3-phosphate dehydrogenase.

In the course of a study on the osidation of various aldehydes by glyceraldehyde 3-phosphate dehydrogenase (l), it was observed that aged preparations of glycolaldehyde 2-phosphate inhibited strongly the activity of glyceraldehyde Q-phosphate dehydrogenase. Differences in inhibitory potency of several orders of magnitude were noted between various batches. A synthetic preparation, kindly supplied by Dr. C. E. Ballou, had no effect even at relatively high concentrations; however, a solution of the same preparation after several months of storage contained a potent inhibitor. A study of the conditions leading to the formation of inhibitor, revealed that it was rapidly formed from glycolaldehyde 2-phosphate in 1 N NaOH at room temperature. Isolation and analysis of the inhibitor showed it to be a tetrose diphosphate. It is the purpose of this paper to report on the preparation of the tetrose diphosphate and on the mechanism of its inhibitory action on glyceraldehyde 3-phosphate dehydrogenase.