How many enzyme molecules are needed for discrimination oriented applications?

Chemical reactions establish a molecular mechanism for information processing in living organisms. Here we consider a simple enzymatic reaction model that can be used to discriminate parameters characterizing periodic reagent inflow. Numerical simulations based on the kinetic equations show that there exist a range of inflow frequencies and amplitudes in which the time evolution of the system is very sensitive to small changes in the values of these parameters.

Realistic parameters for simple models of the Belousov-Zhabotinsky reaction.

We use experimental results to estimate the values of parameters of simple models describing the time evolution of the Belousov-Zhabotinsky reaction proceeding in droplets surrounded by hydrocarbons. The equations with fitted parameters correctly describe the period of oscillations for a large class of experimental conditions at which the reaction is performed.

One dimensional chemical signal diode constructed with two nonexcitable barriers.

Excitable chemical systems can process information coded in excitation pulses. Here we demonstrate the simplest realization of a chemical signal diode that transmits pulses in one direction only. It is constructed with only two different nonexcitable barriers.