Which reaction in the Citric Acid Cycle produces CO2 as a byproduct?

In the Citric Acid Cycle, the conversion of isocitrate to alpha-ketoglutarate is a significant step that produces carbon dioxide (CO2) as a byproduct. This reaction is catalyzed by the enzyme isocitrate dehydrogenase and involves the oxidative decarboxylation of isocitrate.

During the process, isocitrate is oxidized and loses a carboxyl group, which is released as CO2. This reaction not only generates CO2, a key molecule to consider in biological systems due to its role in cellular respiration and impact on the environment, but also reduces NAD+ to NADH, which is crucial for the production of ATP in subsequent steps of cellular respiration.

This specific step is vital in the cycle as it connects the metabolic pathways involving the release of energy, highlighting the integration of carbohydrate metabolism with the citric acid cycle.