Fig. 3

Both Hill and Michaelis–Menten kinetics of PfkA generated using SigmaPlot® 11.2. (A) Activity of PfkA versus varied F6P concentration fitted to Hill equation predicts a relatively high K_m of 1.9 mM for F6P, as well as V_max, while GTP(2 mM) is used as a phosphate donor, in comparison to when (B) ATP(2 mM) is used fitted to Michaelis–Menten kinetics, producing approximately a third of the velocity, but a reduced K_m for F6P. (C) The K_m of GTP and (D) ATP fitted to Michaelis–Menten kinetics determined by varying the concentration of the phosphate donors while keeping the concentration of the substrate constant in the presence of NH₄⁺. All assays were performed in triplicate