Formation of acetylCoA from pyruvate

When pyruvate enters the matrix of mitochondria it is converted to acetylCoA. Coenzyme A (CoA) is a large molecule (and a vitamin) that acts ( as the name implies) as a coenzyme. The conversion of pyruvate to acetylCoA is an coupled oxidation-reduction reaction in which high energy electrons are removed from pyruvate and end up in NADH. The three carbon pyruvate is split into CO2 and the two carbon acetate.