Hyperbolic, noncompetitive inhibition of the ADP phosphorylation reaction by phosphonoacetate with respect to carbamoyl phosphate. Initial rates were determined at varying concentrations of carbamoyl phosphate (1.4-20 mM) and fixed concentrations of phosphonoacetate (0 mM, black; 0.33 mM, red; 0.66 mM, blue; 1.0 mM, green; 1.5 mM, pink; 2.5 mM, cyan; 7.0 mM, purple; 20 mM, dark red). Data were fitted to eqn (10) and the solid lines indicate the least-square fits to the equation. Kinetic parameters from these fits are presented in Table 8.