In a number of cases, the substrate itself can act as an inhibitor. In the case of uncompetitive inhibition, the inactive molecule (S · E · S) is formed by the reaction
Consequently we see that by replacing (I) by (S) in Equation (9-40), the rate law for –rS is
We see that at low substrate concentrations
and the rate increases linearly with increasing substrate concentration.
At high substrate concentrations ...