7. Enzyme Inhibition and Regulation

Competitive inhibitor A at a concentration of 2 μM doubles the apparent K _m for an enzymatic reaction, whereas competitive inhibitor B at a concentration of 9 μM quadruples the apparent K_m. What is the ratio of the K _I for inhibitor B to the K _I for inhibitor A?

The K_I value for a certain competitive inhibitor is 10 mM. When no inhibitor is present, the K_m value is 50 mM. Calculate the apparent K_m when 40 mM inhibitor is present.

Uncompetitive inhibitor A at a concentration of 4 mM cuts the K _m^app in half for an enzymatic reaction, whereas the K_m^app is one-fourth the K_m in the presence of 18 mM uncompetitive inhibitor B. What is the ratio of the K'_I for inhibitor A to the K'_I for inhibitor B?