Fig. 3. Primary kinetic plots from Ensis directus full-length arginine kinase (AK). At each of six different fixed concentrations of substrate A, substrate B is varied through six concentrations. The inverse of reaction velocities (V) from this 6x6 matrix are plotted versus the inverse substrate concentration (ADP or arginine phosphate). Slopes and y-intercepts from each of the six lines in the primary plot are replotted as secondary plots to yield the kinetic constants (K_a and K_ia) for each substrate as well as the V_max of the enzyme. Note that the six lines in the primary plots intersect at or below the origin indicating no, or even negative, synergy of substrate binding.