Figure 3

Simulation. In order to confirm the stability robustness and filtering ability of the synthetic gene network in silico example, we simulate the synthetic gene network with the initial value [200, 40000, 200, 20000] and the desired steady state [1000, 30000, 300, 30000]. (a) with the design parameters (κ _tetR , κ _lacI , κ _cI , κ _eyfp ) = (2000, 2000, 2000, 15000) and (γ _tetR , γ _lacI , γ _cI , γ _eyfp ) = (1.98, 0.05, 0.7, 0.57) in the specified parameter range given in (41), it is seen that the synthetic gene network has robust stability and noise filtering ability to achieve the desired steady state in spite of parameter fluctuations and disturbances in the host cell. (b) If the design parameters are outside the specified range with (κ _tetR , κ _lacI , κ _cI , κ _eyfp ) = (150, 100, 500, 1500) and and (γ _tetR , γ _lacI , γ _cI , γ _eyfp ) = (0.5, 0.05, 0.5, 0.2), the expression of the synthetic gene network is with more fluctuation and cannot achieve the desired steady state under parameter fluctuations and environmental disturbances.