Adenylate-forming reductase, a natural product biosynthesis enzyme that resembles non-ribosomal peptide synthetases, yet serves to modify one substrate, rather than to condense two or more building blocks. The A-domain preferentially accepts phenylpyruvic acid and benzoic acid as substrate. The natural product of the enzyme is not yet known. Contains three distinct domains: an adenylation (A) domain that activates the substrate amino acid which is subsequently covalently linked as a thioester (aminoacyl-S-PCP) to the 4'-phosphopantetheine prosthetic group of the second domain, the peptidyl carrier protein (PCP) domain, as well as a reductase (R) domain of the short-chain dehydrogenase/reductase (SDR) type. Belongs to the adenylate-forming reductase family.