= Solution
The reported coefficients add to
$$
0.29+0.04+0.33+0.17+0.03+0=0.86.
$$
For a complete set of independently scaled activities controlling a steady-state flux, the <flux summation theorem> gives $\sum_i C_i^J=1$, where $C_i^J=\partial\ln J/\partial\ln E_i$. One way to see this is to scale all reaction capacities by the same factor: steady-state concentrations can remain the same while all fluxes scale by that factor, so the summed logarithmic sensitivities equal one. \b[The listed processes therefore leave a net coefficient of about $0.14$ unaccounted for under the model assumptions.] Measurement uncertainty, imperfect inhibitor specificity or incompatible measurements could also contribute to the discrepancy. Control is distributed; neither the sum nor the largest individual coefficient identifies a single universal rate-limiting step.
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