Size-independent differences between the mean of discrete stochastic systems and the corresponding continuous deterministic systems

TitleSize-independent differences between the mean of discrete stochastic systems and the corresponding continuous deterministic systems
Publication TypeJournal Article
Year of Publication2009
AuthorsGadgil, CJ
JournalBulletin of Mathematical Biology
Volume71
Issue7
Pagination1599-1611
Date PublishedOCT
ISSN0092-8240
KeywordsBiochemical reaction kinetics, Continuous systems, Deterministic chemical kinetics, Discrete systems, Stochastic reaction kinetics
Abstract

In this paper, it is shown that for a class of reaction networks, the discrete stochastic nature of the reacting species and reactions results in qualitative and quantitative differences between the mean of exact stochastic simulations and the prediction of the corresponding deterministic system. The differences are independent of the number of molecules of each species in the system under consideration. These reaction networks are open systems of chemical reactions with no zero-order reaction rates. They are characterized by at least two stationary points, one of which is a nonzero stable point, and one unstable trivial solution (stability based on a linear stability analysis of the deterministic system). Starting from a nonzero initial condition, the deterministic system never reaches the zero stationary point due to its unstable nature. In contrast, the result presented here proves that this zero-state is a stable stationary state for the discrete stochastic system, and other finite states have zero probability of existence at large times. This result generalizes previous theoretical studies and simulations of specific systems and provides a theoretical basis for analyzing a class of systems that exhibit such inconsistent behavior. This result has implications in the simulation of infection, apoptosis, and population kinetics, as it can be shown that for certain models the stochastic simulations will always yield different predictions for the mean behavior than the deterministic simulations.

DOI10.1007/s11538-009-9415-9
Type of Journal (Indian or Foreign)Foreign
Impact Factor (IF)1.859
Divison category: 
Chemical Engineering & Process Development