Which of the following is a competitive inhibitor of Succinate Dehydrogenase enzyme?
High-Yield Explanation
Most frequently, in competitive inhibition, the inhibitor (I) binds to the substrate-binding poion of the active site thereby blocking access by the substrate. The structures of most classic competitive inhibitors, therefore, tend to resemble the structures of a substrate and thus are termed substrate analogues. Inhibition of the enzyme succinate dehydrogenase by malonate illustrates competitive inhibition by a substrate analog. Succinate dehydrogenase catalyzes the removal of one hydrogen atom from each of the two-methylene carbons of succinate both succinate and its structural analog malonate (-OOC--CH2-- COO-) can bind to the active site of succinate dehydrogenase, forming an ES or an EI complex, respectively. However, since malonate contains only one methylene carbon, it cannot undergo dehydrogenation. Ref: KD Tripathi 8th ed.