Coenzyme A

What it isThe universal acyl-group carrier, synthesized from pantothenic acid (vitamin B5).

Why it mattersAcetyl-CoA sits at the crossroads of carbohydrate, fat, and protein metabolism — nothing in intermediary metabolism moves without it.

What it changesPharmacologically it matters as valproate’s hostage: valproyl-CoA sequestration is one proposed mechanism of valproate hepatotoxicity and hyperammonemia.