TY - JOUR

T1 - Stochastic bimodalities in deterministically monostable reversible chemical networks due to network topology reduction

AU - Artyomov, Maxim N.

AU - Mathur, Manikandan

AU - Samoilov, Michael S.

AU - Chakraborty, Arup K.

N1 - Funding Information:
We would like to acknowledge helpful discussions with Jayajit Das, Jason Locasale, and Adam Arkin. Funding provided through NIH Director’s Pioneer Award to A.K.C. and Contract No. IPO1/AI071195/01 (A.K.C.).

PY - 2009

Y1 - 2009

N2 - Recently, stochastic simulations of networks of chemical reactions have shown distributions of steady states that are inconsistent with the steady state solutions of the corresponding deterministic ordinary differential equations. One such class of systems is comprised of networks that have irreversible reactions, and the origin of the anomalous behavior in these cases is understood to be due to the existence of absorbing states. More puzzling is the report of such anomalies in reaction networks without irreversible reactions. One such biologically important example is the futile cycle. Here we show that, in these systems, nonclassical behavior can originate from a stochastic elimination of all the molecules of a key species. This leads to a reduction in the topology of the network and the sampling of steady states corresponding to a truncated network. Surprisingly, we find that, in spite of the purely discrete character of the topology reduction mechanism revealed by "exact" numerical solutions of the master equations, this phenomenon is reproduced by the corresponding Fokker-Planck equations.

AB - Recently, stochastic simulations of networks of chemical reactions have shown distributions of steady states that are inconsistent with the steady state solutions of the corresponding deterministic ordinary differential equations. One such class of systems is comprised of networks that have irreversible reactions, and the origin of the anomalous behavior in these cases is understood to be due to the existence of absorbing states. More puzzling is the report of such anomalies in reaction networks without irreversible reactions. One such biologically important example is the futile cycle. Here we show that, in these systems, nonclassical behavior can originate from a stochastic elimination of all the molecules of a key species. This leads to a reduction in the topology of the network and the sampling of steady states corresponding to a truncated network. Surprisingly, we find that, in spite of the purely discrete character of the topology reduction mechanism revealed by "exact" numerical solutions of the master equations, this phenomenon is reproduced by the corresponding Fokker-Planck equations.

UR - http://www.scopus.com/inward/record.url?scp=70450252161&partnerID=8YFLogxK

U2 - 10.1063/1.3264948

DO - 10.1063/1.3264948

M3 - Article

C2 - 19929080

AN - SCOPUS:70450252161

VL - 131

JO - Journal of Chemical Physics

JF - Journal of Chemical Physics

SN - 0021-9606

IS - 19

M1 - 195103

ER -