Peroxisomes subcellular fractionation

Rather, the isolated subcellular fraction is a mitochondrial fraction, which indicates that its major components are mitochondria. Other cellular components that may be present are lysosomes, cell fragments, nuclear fragments, and microbodies (peroxisomes). The purity of the fraction depends on the source of the extract and the method chosen for isolation. 

Subcellular fractions were prepared by standard differential and density gradient centrifugation protocols. Purified fractions of mitochondria and peroxisomes were prepared by Percoll and Nycodenz centrifugation, respectively. The following marker... 

Similarly to the studies in rat liver, a-oxidation in human liver homogenates depended on the presence of cofactors for activation and for hydroxylation." In agreement with other reports, formation of 2-hydroxy-3-methyl-branched chain acyl-CoA was confined to subcellular fractions enriched in peroxisomes." Verhoeven et al showed that pristanal is formed in human liver homogenates incubated with phytanic acid, confirming our findings in rat liver peroxisomes. ... 

Activation of the fatty acids to their respective CoA esters, is a necessary step prior to oxidation. DHA was converted to its CoA ester in all subcellular fractions, but was a poor substrate for oxidation in both the mitochondrial- and the peroxisomal fractions. Compared to EPA-CoA, DHA-CoA was more effectively synfliesized in the peroxisomal than the mitochondrial fraction, espedally in animals treated with 3-thia fatty acids. It has been reported that very long chain fatty acyl-CoA synthases as lignoceryl-CoA are absent in mitochondria and DHA-CoA syndiase activity measured in the mitochondrial fraction, might also be due to contamination of peroxisomes. ... 

The most active subcellular fraction for conjugation of bile salt CoA intermediates with taurine or glycine is microsomal (32). The system is strongly stimulated by the addition of a lysosome fraction, which may contain some peroxisome particles (33). Taurine and glycine are the only amino acids known to conjugate with bile acids in man, and the conjugation appears to be limited to the liver. In healthy adults, the usual glycine/taurine ratios are... 

This enzyme can be used as a market enzyme for peroxisomes in subcellular fractionation studies. 

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