Description_x000D_ Application_x000D_ Phospho(enol)pyruvic acid trisodium salt hydrate has been used in:_x000D_ • several enzyme activity assays, such as PRPP synthetase (PRPPS) assay, ribokinase (RK) assay, adenine phosphoribosyltransferase (APRT) assay_x000D_ • in the reaction mixture for enzyme kinetic assay to determine platelet-derived growth factor receptor α (PDGFRA) kinetic parameters_x000D_ • as a component in buffer B to react with adenosine diphosphate (ADP) to form adenosine triphosphate (ATP) for energy charge measurement_x000D_ Biochem/physiol Actions_x000D_ Phosphoenolpyruvic acid plays a major role in the initial step of glycolysis by acting as an inhibitor of hexokinase, phosphoglucose isomerase, phosphofructokinase and aldolase._x000D_ Phospho(enol)pyruvic acid (PEP) is involved in glycolysis and gluconeogenesis. In glycolysis, PEP is metabolized by pyruvate kinase to yield pyruvate. In plants, PEP is involved in the formation of aromatic amino acids as well as in the carbon fixation pathway.