While conducting an experiment, you realize that a competitive inhibitor was interfering with your reaction. How could you overcome this problem?

Question

A.  Add a non-competitive inhibitor to the reaction.
B.  Add a cofactor to the reaction.
C.  Increase the concentration of the correct substrate in the reaction.
D.  Add an allosteric activator to the reaction.

Clarify Question
What is the key concept addressed by the question?
What type of thinking is required?

  Gather Content
  What do you already know about enzymes and competitive inhibition? What other information is related to the question?

  Choose Answer
  Do you have all the information needed to answer the question?

  Reflect on Process
  Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?

Answer 1

C.  Increase the concentration of the correct substrate in the reaction.


Clarify Question
What is the key concept addressed by the question?
        · The question asks for you to overcome a problem where a competitive inhibitor is interfering with a reaction.
What type of thinking is required?
        · You are being asked to take what you already know about enzymes and competitive inhibition and apply your understanding to determine how to rectify the problem.

  Gather Content
  What do you already know about enzymes and competitive inhibition? What other information is related to the question?
        · To solve this problem you’ll need to apply what you know about how competitive inhibition regulates enzyme function. Recall that enzyme function can be inhibited competitively, noncompetitively, and allosterically. How does competitive inhibition compare to the other types of inhibition, and keeping that mechanism in mind, what could you do to overcome the inhibition?

  Choose Answer
  Do you have all the information needed to answer the question?
        · The question indicates that a competitive inhibitor is messing up your reaction. If you added a noncompetitive inhibitor, you would like still end up with decreased enzyme functionality because it changes the enzyme structure and prevents substrate binding altogether. An allosteric inhibitor would essentially function in the same way as a noncompetitive inhibitor, and likewise not help your reaction.
        · A cofactor might conceivably help overcome the latent inhibition, but only if the cofactor outcompeted the inhibitor for the active site.
        · That leaves increasing substrate concentration as the best solution. Recall that with competitive inhibition, the inhibitor directly competes with the substrate for the enzyme’s active site. Both inhibitor and substrate try to occupy the same physical space within the structure of the enzyme. Increasing substrate concentration would serve up more reactants to the active site per unit time than the inhibitor, effectively washing out the effects of the inhibitor.

  Reflect on Process
  Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
        · Answering this question correctly depended on your ability to use your understanding of enzymes and competitive inhibition to determine what would be the most likely solution to restore your reaction.
        · If you got an incorrect answer, did you recall how competitive inhibition works? Did you contrast that with noncompetitive and allosteric inhibition, which don’t involve the active site and therefore wouldn’t solve the problem at all? Were you able to decipher that the best solution was to simply outcompete the competitive inhibitor by increasing substrate?