Question

The substrate of $1^{st}$ oxidation and $4^{th}$ oxidation of Krebs’ cycle are formed respectively by

• A. dehydration and hydration
• B. hydration and dehydration
• C. decarboxylation and cleavage
• D. hydration and hydration

Answer 1

Answer: (D)

The substrate of Ist oxidation of Krebs' cycle is isocitrate. It is formed by hydration of $cis$ -aconitate. The substrate of $4^{\text{th }}$ oxidation of Kreb's cycle is malate. It is formed by hydration of fumarate.