So even though in step three we actually formed the acetyl coenzyme a structure, we essentially are able to transfer that to carbon acetyl group from the pyruvate and onto that carrier coenzyme a molecule. We did not regenerate the lipoamide. And that's where the final enzyme comes into play. Dihydrolipole dehydrogenase reforms the oxidized version of lipoamide. Because remember this step, we actually reduced this structure because two electrons from this molecule were abstracted and given to the lipoamide. And so, in the final step, we not only regenerate the lipoamide coenzyme that can be then used to restart another cycle of pyruvate carboxylation, but we also oxidize this molecule, the dihydrolipoamide.