A New Enzyme with the Glycolytic Function of Pyruvate Kinase

Extracts from Entamoeba histolytica trophozoites contain a new enzyme which catalyzed the reversible transformation of phosphoenolpyruvate to pyruvate according to the following equation P-enolpyruvate + AMP + PPi ⇄ pyruvate + ATP + Pi The enzyme has been purified 30-fold and freed from interfering amounts of adenylate kinase activity. Unlike known bacterial, yeast, and muscle pyruvate kinases, for which ADP is a substrate, the amebal enzyme employs AMP. It is inactive in the forward direction in the absence of inorganic pyrophosphate. It is suggested that the new enzyme be called pyruvate-phosphate ligase (AMP) and that for the trivial name this be shortened by dropping the parenthetical part.