In enzymology, an acyl-CoA oxidase (EC 1.3.3.6) is an enzyme that catalyzes the chemical reaction

acyl-CoA + O₂ ${\displaystyle \rightleftharpoons }$ trans-2,3-dehydroacyl-CoA + H₂O₂

Thus, the two substrates of this enzyme are acyl-CoA and O₂, whereas its two products are trans-2,3-dehydroacyl-CoA and H₂O₂.

This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-CH group of donor with oxygen as acceptor. The systematic name of this enzyme class is acyl-CoA:oxygen 2-oxidoreductase. Other names in common use include fatty acyl-CoA oxidase, acyl coenzyme A oxidase, and fatty acyl-coenzyme A oxidase. This enzyme participates in 3 metabolic pathways: fatty acid metabolism, polyunsaturated fatty acid biosynthesis, and ppar signaling pathway. It employs one cofactor, FAD.

As of late 2007, 6 structures have been solved for this class of enzymes, with PDB accession codes 1IS2, 1W07, 2DDH, 2FON, 2IX5, and 2IX6.

• ACOX1
• ACOX3

• Kawaguchi A, Tsubotani S, Seyama Y, et al. (November 1980). "Stereochemistry of dehydrogenation catalyzed by Acyl-CoA oxidase". J. Biochem. 88 (5): 1481–6. doi:10.1093/oxfordjournals.jbchem.a133118. PMID 7462191.
• Osumi T, Hashimoto T, Ui N (June 1980). "Purification and properties of acyl-CoA oxidase from rat liver". J. Biochem. 87 (6): 1735–46. doi:10.1093/oxfordjournals.jbchem.a132918. PMID 7400120.