How many enzyme molecules are needed for discrimination oriented applications?

Abstract

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. However, the kinetic equations are derived for the thermodynamic limit, whereas in a real biological medium, like a cell, the number of enzyme molecules is an integer and finite. We use stochastic simulations to estimate discriminator reliability as a function of the number of enzyme molecules involved. For systems with 10 000 molecules the functionality predicted by kinetic equations is confirmed. If the number of molecules is decreased to 100, discrimination becomes unreliable.

Cancer classification with a network of chemical oscillators

“…Adding the third predictor significantly increases the maximum mutual information. It becomes 0.916 bit for the predictor triple (1,2,6). Therefore, these predictors have been used in this paper.…”

“…high temperatures, alternative computing strategies can lead to more efficient information processing. 1,2 For instance it is difficult to apply conventional computers at a cellular level in living organisms due to problems such as introduction of electronic components inside the cells, their potential influence on biological processes, electrical energy supply etc. Nevertheless nature has developed computing mechanisms that allow for information processing in cells.…”