The structure of FAD, a molecule required for the activity of succinate dehydrog
ID: 520179 • Letter: T
Question
The structure of FAD, a molecule required for the activity of succinate dehydrogenase, is shown. What term best describes this compound in relation to the enzyme? a) apoenzyme b) coenzyme c) holoenzyme d) proenzyme Which is true of enzymes as catalysts? a) Enzymes bind to substrates covalently. b) Enzymes often act by decreasing the energy change for a reaction. c) Enzymes increase reaction rates by decreasing a reaction's activation energy. d) Enzymes act by increasing the solubility of a substrate in solution.
Explanation / Answer
Ans 4. B) coenzyme
Coenzymes are the molecules non protein in nature that are required for the functioning of the enzyme.
FAD acts as a coenzyme and binds covalently to succinate dehydrogenase enzyme as the gibbs free energy change associated with the enzyme alone is less ( -80 kcal/mol). So it binds with FAD as it is easier to reduce with higher reduction potential.