Optimum activity of the phosphofructokinase from Ascaris suum requires more than one metal ion

Initial rate and isotope partitioning studies are carried out as a function of Mg(super 2+) in the absence and presence of fructose 2,6-bisphosphate (F26P2) in order to determine whether more than one Mg(super 2+) is required for optimum activity of phosphofructokinase (PFK). The results show that the kinetic mechanism changes from ordered to random as the Mg(super 2+) concentration decreases and in the presence of F26P2, the mechanism becomes random as a result of an increase in the affinity of F6P (fructose 6-phosphate).