A Simple Allosteric Regulation

The regulatory curve is derived by again solving the equation 

When (/t - 1) and (/i - 1) have different signs, 1, and we have negative cooperativity between A and R. In this case R is an inhibitor to the site A. We have defined the fully active enzyme whenever 0 0.8. Similarly, we may choose a lower bound on 6, say 0.2, to define the inactive enzyme. In order to have an efficient regulation we require that as increases, Rg falls below -0.2. The limiting 

in order to fall below the lower bound of 0.2, must be at most 0.25. We demonstrate in Fig. 8.8 the behavior of a system with y above and below this 

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