Which of the following contains a high-energy bond that is used for a substrate-level phosphorylation in the citric acid cycle? The Role of High-Energy Bond in Substrate-Level Phosphorylation in the Citric Acid Cycle

The Role of High-Energy Bond in Substrate-Level Phosphorylation in the Citric Acid Cycle

The citric acid cycle, also known as the Krebs cycle or tricarboxylic acid cycle, is a series of metabolic reactions that play an important role in the energy production of cells. Substrate-level phosphorylation is a key step in the citric acid cycle where energy is transferred from a high-energy bond to a phosphate group. This energy transfer is essential for the production of ATP—the molecule used for energy storage in cells. The high-energy bond used for this process is derived from the breakdown of acetyl-CoA, a molecule that contains two high-energy phosphate bonds. The enzymatic cleavage of these two bonds drives the reaction, releasing a molecule of carbon dioxide and a molecule of CoA-SH—a molecule that can be used in additional metabolic processes. During the cleavage, the acetyl-CoA also produces a molecule of adenosine triphosphate (ATP) as well as a molecule of NADH. This ATP and NADH are used to drive further metabolic reactions and produce energy for the cell. As such, this high-energy bond from acetyl-CoA is essential for substrate-level phosphorylation in the citric acid cycle. Cont….