Acyl‐CoA dehydrogenases and acyl‐CoA oxidases

Abstract
Acyl‐CoA dehydrogenases and acyl‐CoA oxidases are two closely related FAD‐containing enzyme families that are present in mitochondria and peroxisomes, respectively. They catalyze the dehydrogenation of acyl‐CoA thioesters to the corresponding trans‐2‐enoyl‐CoA. This review examines the structure of medium chain acyl‐CoA dehydrogenase, as a representative of the dehydrogenase family, with respect to the catalytic mechanism and its broad chain length specificity. Comparing the structures of four other acyl‐CoA dehydrogenases provides further insights into the structural basis for the substrate specificity of each of these enzymes. In addition, the structure of peroxisomal acyl‐CoA oxidase II from rat liver is compared to that of medium chain acyl‐CoA dehydrogenase, and the structural basis for their different oxidative half reactions is discussed.