acyl carrier protein

(ACP) A low-molecular-weight conjugated protein. It forms a complex with the enzymes of fatty acid synthesis and binds the acyl group of the growing fatty acid molecule, thus bringing enzymes and substrate together. The prosthetic group of ACP, 4'-phosphopantetheine, is identical to the acyl-carrying portion of *coenzyme A . See also fatty acid metabolism, malonyl ACP.