Description Coenzyme A (CoA, CoASH, HSCoA) is a coenzyme that facilitates enzymatic acyl-group transfer reactions and supports the synthesis and oxidation of fatty acids. CoA is involved in the mechanisms of a wide variety of enzymes. CoA is a thiol compound subject to oxidation. Oxidized CoA may be used to study reduction systems (CoA disulfide reductase (CoADR) systems) that regenerate reduced CoA in vivo. Furthermore, oxidized CoA may be used to study unique functions of this molecule in vivo.