DEPENDENCE OF FLUX DISTRIBUTION AND SYSTEM COORDINATION ON DYNAMICAL STATES FOR BIOCHEMICAL SYSTEMS WITH MULTIPLE COEXISTING STATES

Abstract

Flux distribution and system coordination in branched biochemical systems with a source producing multiple coexisting states have been studied both theoretically and numerically. For such systems, flux distribution depends sensitively on the dynamical states and the parameter values of enzymatic kinetics at branching point. Various dynamical states including noise-induced new states can be located by superimposing noisy fluctuations on a branched biochemical system with multiple coexisting states. Once noise induces transitions or new dynamical states, the flux through a specific branch may increase, maintain or decrease, depending on parameter values of enzymatic kinetics at branching point. Furthermore, system coordination can be destroyed by noise-induced dynamical changes. When at least one state cannot be coordinated in the absence of noise, noise-induced transitions may destroy system coordination. When all coexisting states are coordinated in the absence of noise, noise-induced new states may be still able to destroy system coordination. It is revealed that destruction of system coordination is due to the interaction of enzyme saturation and noise-induced dynamical changes. Finally, control of flux distribution and maintenance of system coordination for biochemical systems with multiple coexisting states are discussed.