The hydride ion is accepted by the NAD(P)+ bound to the Rossman fold. Unique interactions between the cofactor and the Rossman fold facilitate an isomerization of the enzyme that releases the cofactor while maintaining the integrity of the active site.[11] A water molecule enters the active site and is subsequently activated by a glutamate residue. The activated water then attacks the thioester enzyme-substrate complex in nucleophilic reaction that regenerates the free enzyme, and releases the corresponding carboxylic acid.