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Mitigating Competitive Inhibitors


In the regeneration phase of the Krebs cycle of aerobic respiration in eukaryotic cells, succinate is converted to fumarate, which is converted to malate, which is then converted back to oxaloacetate. Succinate dehydrogenase is the enzyme that converts succinate to fumarate.

When malonic acid is introduced into​ the mitochondrial matrix, it binds to the active site of succinate dehydrogenase and acts as a competitive inhibitor.

Which of the following treatments would BEST mitigate the inhibiting effects of malonic acid?


Increasing the amount of fumarate so as to pull the reaction away from equilibrium.


Denaturing the enzyme to change the shape of its active site so that malonic acid could no longer fit.


Increasing the amount of succinate so as to outcompete malonic acid for the active site of the enzyme.


Lowering the temperature of the cell to decrease the frequency that malonic acid entered the active site of the enzyme.