A Novel Acyl-CoA Oxidase That Can Oxidize Short-chain Acyl-CoA in Plant Peroxisomes

• Published in: The Journal of biological chemistry 1999-04, Vol.274 (18), p.12715-12721
• Main Authors: Hayashi, H, De Bellis, L, Ciurli, A, Kondo, M, Hayashi, M, Nishimura, M
• Format: Article
• Language: English
• Subjects: Acyl-CoA Dehydrogenase; Acyl-CoA Dehydrogenases - genetics; Acyl-CoA Dehydrogenases - metabolism; Amino Acid Sequence; Arabidopsis - enzymology; Arabidopsis - growth & development; Arabidopsis thaliana; DNA, Complementary; Microbodies - enzymology; Microscopy, Immunoelectron; Molecular Sequence Data; Oxidation-Reduction; Sequence Homology, Amino Acid; Substrate Specificity
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.274.18.12715

Short-chain acyl-CoA oxidases are β-oxidation enzymes that are active on short-chain acyl-CoAs and that appear to be present in higher plant peroxisomes and absent in mammalian peroxisomes. Therefore, plant peroxisomes are capable of performing complete β-oxidation of acyl-CoA chains, whereas mammalian peroxisomes can perform β-oxidation of only those acyl-CoA chains that are larger than octanoyl-CoA (C 8 ). In this report, we have shown that a novel acyl-CoA oxidase can oxidize short-chain acyl-CoA in plant peroxisomes. A peroxisomal short-chain acyl-CoA oxidase from Arabidopsis was purified following the expression of the Arabidopsis cDNA in a baculovirus expression system. The purified enzyme was active on butyryl-CoA (C 4 ), hexanoyl-CoA (C 6 ), and octanoyl-CoA (C 8 ). Cell fractionation and immunocytochemical analysis revealed that the short-chain acyl-CoA oxidase is localized in peroxisomes. The expression pattern of the short-chain acyl-CoA oxidase was similar to that of peroxisomal 3-ketoacyl-CoA thiolase, a marker enzyme of fatty acid β-oxidation, during post-germinative growth. Although the molecular structure and amino acid sequence of the enzyme are similar to those of mammalian mitochondrial acyl-CoA dehydrogenase, the purified enzyme has no activity as acyl-CoA dehydrogenase. These results indicate that the short-chain acyl-CoA oxidases function in fatty acid β-oxidation in plant peroxisomes, and that by the cooperative action of long- and short-chain acyl-CoA oxidases, plant peroxisomes are capable of performing the complete β-oxidation of acyl-CoA.