Carboxylation and dephosphorylation of phosphoenol-3-fluoropyruvate by maize leaf phosphoenolpyruvate carboxylase

The analogue (Z)-phosphoenol-3-fluoropyruvate [(Z)-3-fluoro-2-(phosphono-oxy)propenoic acid] was tested as substrate of maize leaf phosphoenolpyruvate carboxylase. Studies with NaH14CO3 indicate that the analogue is carboxylated by the enzyme. However, this reaction accounts for only one-tenth of the activity measured by Pi liberation. The rest of the analogue is merely dephosphorylated. This is the first analogue for which both carboxylation and dephosphorylation have been observed.