Plastid pyruvate kinase catalyzes the physiologically irreversible reaction of phosphoenolpyruvate and ADP to form pyruvate and ATP. Based on experimental studies of the orthologous Arabidopsis thaliana plastid proteins (Andre et al. 2007; Baud et al. 2007), the active form of the rice enzyme is inferred to be a complex of four molecules of PFK-ALPHA protein and four of PFK-BETA protein.
