ATP + pyruvate = ADP + H(+) + phosphoenolpyruvate Regulated by phosphoenolpyruvate substrate and allosteric effectors such as fructose 1,6 diphosphate and magnesium. Carbohydrate degradation; glycolysis; pyruvate from D-glyceraldehyde 3-phosphate: step 5/5. Homotetramer. Belongs to the pyruvate kinase family.