The dual location of β-oxidation enzymes in germinating pea cotyledons.

β-Oxidation enzymes were detected both in the mitochondria and microbodies of pea cotyledons. Intact mitochondria did not show β-oxidation enzyme activity but in ruptured mitochondria this activity was high. It is apparent that the mitochondrial membrane barrier prevents rapid access of acyl-CoA substrates to matrix β-oxidation sites. Removal of the membrane barrier permits rapid access of acyl-CoAs and these enzyme activities may then be measured.