Select all true statements regarding competitive inhibitors

Select all true statements regarding competitive inhibitors. (has multiple answers)

1. Could be used as a therapeutic agent in some cases

2. Can decrease the apparent Km of an enzyme

3. Prevents binding of substrate to enzyme

4. Do not decrease the apparent Vmax of an enzyme

Solution

Answer:

1. Could be used as a therapeutic agent in some cases

. Prevents binding of substrate to enzyme

Explantion:

In competitive inhibition, the inhibitor usually has structural similarity with the natural substrate and competes with the substrate for access to the active site. The inhibitor has affinity for the active site, and if it binds more tightly than the substrate, then it is an effective competitive inhibitor. Conversely, if it binds less strongly, it is considered as a poor inhibitor. In competitive inhibition, the inhibitor can bind only to the free enzyme and not with the enzyme-substrate complex. Hence, inhibition can be overcome by increasing the concentration of substrate in the reaction mixture. By outcompeting with substrate, Vmax can still be achieved. However, in the presence of inhibitor, substrate concentration has to be increased to achieve Vmax. This will increase the Km value. The competitive inhibitor does not affect Vmax. One potential stage for therapeutic intervention is the use of competitive inhibitors to block dNTP binding to the polymerase\'s active site