Table III.

Substrate specificity of ACOX and ACAD activities in peroxisomes and mitochondria from embryonic axes of earlygerminating sunflower seeds

Substrate	ACOX Activity in Peroxisomes	ACAD Activity in Mitochondria
50 μm	nmol min−1 mg−1
Butyryl-CoA	18  ± 1	11  ± 2
Isobutyryl-CoA	NDa	14  ± 3
Isovaleryl-CoA	0.70  ± 0.07	ND
Octanoyl-CoA	10  ± 1	7  ± 1
Decanoyl-CoA	16  ± 2	5  ± 1
Palmitoyl-CoA	16  ± 1	10  ± 3
Stearoyl-CoA	3.4  ± 0.3	6  ± 1

ACOX and ACAD activities were measured as described in Methods. Partially purified peroxisomes and purified mitochondria were isolated from embryonic axes of 6-h-soaked sunflower seeds, as described in Methods and in Results. Results are the means ± se of at least three experiments.

^aND, Not detected.