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Figure 9 | BMC Systems Biology

Figure 9

From: (Im)Perfect robustness and adaptation of metabolic networks subject to metabolic and gene-expression regulation: marrying control engineering with metabolic control analysis

Figure 9

The fragility of the ADP concentration with respect to perturbation in the demand flux as the protein degradation rate constant k b changes. The fragility is zero when the k b is zero; the maximum fragility equals the ATP/(ADP + ATP) ratio. The solid line represents the fragility under a ATP/(ADP + ATP) ratio of 0.5 at steady state; the dot-dash line is with a ratio of 0.4; and the dashed line is with a ratio of 0.6. The half maximum fragility is attained when k b satisfies (23), e.g. k b  = 0.3333 under a ATP/(ADP + ATP) ratio of 0.5.

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