Acyl-CoA oxidase 1 from Arabidopsis thaliana. Structure of a key enzyme in plant lipid metabolism.
The peroxisomal acyl-CoA oxidase family plays an essential role in lipid metabolism by catalyzing the conversion of acyl-CoA into trans-2-enoyl-CoA during fatty acid beta-oxidation. Here, we report the X-ray structure of the FAD-containing Arabidopsis thaliana acyl-CoA oxidase 1 (ACX1), the first three-dimensional structure of a plant acyl-CoA oxidase. Like other acyl-CoA oxidases, the enzyme is a dimer and it has a fold resembling that of mammalian acyl-CoA oxidase. A comparative analysis including mammalian acyl-CoA oxidase and the related tetrameric mitochondrial acyl-CoA dehydrogenases reveals a substrate-binding architecture that explains the observed preference for long-chained, mono-unsaturated substrates in ACX1. Two anions are found at the ACX1 dimer interface and for the first time the presence of a disulfide bridge in a peroxisomal protein has been observed. The functional differences between the peroxisomal acyl-CoA oxidases and the mitochondrial acyl-CoA dehydrogenases are attributed to structural differences in the FAD environments.
Pedersen
Lise
L
Carlsberg Laboratory, Gamle Carlsberg Vej 10, DK-2500 Valby, Denmark.
Henriksen
Anette
A
D042962:Acyl-CoA Oxidase / Q000737:chemistry / Q000378:metabolism*; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology*; D050356:Lipid Metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D017386:Sequence Homology, Amino Acid
D011994:Recombinant Proteins; D042962:Acyl-CoA Oxidase