Acyl-CoA oxidase activity of G. thermoleovorans B23. a, Induction of acyl-CoA oxidase activity by alkanes or fatty acids. G. thermoleovorans B23 was cultivated in the presence of alkanes or single fatty acid at 70°C for 5 days (open bar) and 10 days (closed bar). Cells grown on simple LBM were used as a negative control. Acyl-CoA oxidase activity was measured using tetradecanoyl-CoA as a substrate. One unit was defined as the amount of enzyme producing 1 nmol of H2O2 in one min. b, Substrate specificity of acyl-CoA oxidase. Enzyme activity was compared each other using acyl-CoA with various alkyl chain length.