have the same function, there is little overlap among their amino acid sequences. For example, only 40 out of 302 amino acid sequences (13%) are the same between monofunctional peroxisomal and mitochondrial enzymes in humans. In fact, in mammals, the peroxisomal enzyme has an extra N-terminal domain that is not present in the mitochondrial counterpart. Also, it has been found to be a subunit of the peroxisomal trifunctional enzyme (pTFE) and contributes only to minor cleavages of the fatty acid chain. In that sense, for many higher organisms, the mitochondrial enzyme is essential for deriving maximum energy from lipids and fueling muscles. Mitochondria (both short- and long-chain) of rat liver contain more than one enoyl Co-A isomerase. To further support the idea that short- and long-chain isomerases elute at different concentration of potassium phosphate concentration, they do not share similar primary polypeptide structure, hence they must not be evolutionarily related. Peroxisomes of plants and of rat liver are very different in the way they operate. Despite their primary structure similarities, there are differences among the different specimen. To begin with, the peroxisomes of rat liver are a multifunctional enzyme including enoyl-CoA isomerase, enoyl-CoA hydratase, and L-(−)-3-hydroxyacyl-CoA dehydrogenase. Three different enzymes reside on this entity (multifunctional protein) allowing this enzyme to perform isomerization, hydration, and dehydration. Isomerase activity on the multifunctional enzyme occurs at the amino-terminal catalytic half of the protein along with the hydratase activity. The dehydrogenase activity of enoyl-CoA occurs in the carboxyl-terminal. Upon further investigation of the CoA binding site on the amino-terminal half of the multifunctional protein, the CoA substrate is not transferred through the aqueous phase from the isomerization phase to the site of hydration or does not have a bulk phase. This removes the need for a substrate transferring enzyme. On the other hand, the cotyledons convert long-chain 3-trans-enoyl-CoA, long-chain 3-cis-enoyl-CoA, and short-chain 3-cis-enoyl-CoA species into their 2- trans-enoyl-CoA respective forms. As previously mentioned, plant enoyl-CoA isomerase exclusively forms the 2-trans isomer as product. It does not act on 4-cis-enoyl-CoA species or 2-trans- 4-trans-dienoyl-CoA species. In comparing the products of the plant peroxisome and the multifunctional enzyme of rat liver, the plant has no hydratase activity. The Plant form did not form a 2-cis-isomer (from enoyl-CoA hydratase) or D- or L- 3 hydroxy derivative (L-(−)-3-hydroxyacyl-CoA dehydrogenase): products of multifunctional enzyme of rat liver. The turnover rates of these the two sub divisions of peroxisomes are