Enzymic product formation curves with the normal or diffusion limited reaction mechanism and in the presence of substrate receptors.

1. The enzymic product formation curves for several enzymes have been studied. 2. The product formation kinetics was related to the initial velocity kinetics and to the diffusion rate limited kinetics. 3. The time curves revealed new constants characterizing structural and binding properties of the enzymic systems which are not revealed from initial velocities. 4. The influence of selected inhibitors on the time curves has been studied. 5. The time curves revealed the specific substrate-receptor binding which was not revealed from initial velocities. 6. The product formation kinetics of acid phosphatase, beta-amylase and NADPH2 cytochrome-c reductase in the absence and in the presence of inhibitors, mercuric acetate and o-iodosobenzoate is described. 7. The time curves revealed the binding of cytochrome-c to the specific natural protein receptors. 8. The activation energies of acid phosphatase and beta-amylase were determined from the time curves.