For the same enzyme sample described in Problem 27, what would your results show if a reversible inhibitor is present?

Enzyme inhibitors stop enzymes from working. No other substrate can attach to the active site since the irreversible inhibitor binds to it irreversibly.

To determine if the material includes an irreversible enzyme inhibitor, it is diluted 100-fold. If the enzyme inhibitor is irreversible, dilution will have no effect. Even if the irreversible inhibitor is present, when the sample is diluted100 times, the enzyme solution activity is likewise 100 times lower. It's because the dilution factor is less important than the enzyme inhibitor's affinity for the enzyme.

$$\begin{gathered} {\text{K}}_{\text{I}}\text{=}\frac{\left[\text{E}\right]\left[\text{I}\right]}{\left[\text{EI}\right]} \\ \frac{{\text{K}}_{\text{I}}}{\left[\text{I}\right]}\text{=}\frac{\left[\text{E}\right]}{\left[\text{EI}\right]} \end{gathered}$$

If the reversible inhibitor is present, dilution will reduce the enzyme concentration and the inhibitor concentration. As a result, the inhibitor's separation from the enzyme becomes more pronounced. Because the amount of uncontrolled enzyme is large at low concentrations, the enzyme solution activity will be higher subsequently.