Pyruvate Dehydrogenase

This animation shows how the pyruvate dehydrogenase enzyme complex converts pyruvate into acetyl-CoA, linking key cellular respiration processes. It is the second of six animations about cellular respiration. These animations bring to life the molecular engines inside mitochondria that generate ATP, the main source of chemically stored energy used throughout the body.

Pyruvate, a product of glycolysis (first animation), is the source of carbon and electrons for aerobic respiration. The reactions linking pyruvate with aerobic respiration are performed by the pyruvate dehydrogenase enzyme complex. This complex catalyzes multiple reactions with its three types of enzymes. It ultimately uses pyruvate to produce acetyl-CoA, which can enter the citric acid cycle (third animation); NADH, which can enter the electron transport chain (fourth animation); and carbon dioxide, which leaves the body as waste.

The animation is appropriate for teaching advanced high school or college-level students the in-depth actions of pyruvate dehydrogenase. For more general audiences, the animation can be used as an example of enzymes and chemical reactions in action. Depending on students’ background, it may be helpful to pause the animation at various points to discuss different reactions or molecules. 

All six cellular respiration animations are also available in a YouTube playlist.

An audio descriptive version of the film is available via our media player.