Purification and properties of rat liver peroxisomal very-long-chain acyl-CoA synthetase.

Abstract

It is generally accepted that there are two different acyl-CoA synthetases in rat liver peroxisomes. One is long-chain acyl-CoA synthetase, and the other very-long-chain acyl-CoA synthetase. Nowadays, the nature of long-chain acyl-CoA synthetase is well-known, but that of very-long-chain acyl-CoA synthetase remains unclear. Very-long-chain acyl-CoA synthetase has been extracted from the washed membrane fraction of frozen rat liver peroxisomes with a buffer containing a detergent, and has been purified by chromatography on Ultrogel AcA 34, calcium phosphate gel/cellulose, blue dextran-Sepharose 4B and DEAE-Toyopearl. The molecular masses of the native enzyme and the subunit were estimated to be 235 and 70 kDa, respectively. This enzyme showed marked differences in behavior from long-chain acyl-CoA synthetase during purification. The carbon chain length specificity of very-long-chain acyl-CoA synthetase differed from that of long-chain acyl-CoA synthetase. Very-long-chain acyl-CoA synthetase was active toward long- and very-long-chain fatty acids, but more active toward very-long-chain fatty acids compared with long-chain acyl-CoA synthetase. Antibodies against long-chain acyl-CoA synthetase did not cross-react to very-long-chain acyl-CoA synthetase. Based on these data, the final enzyme preparation is judged to be highly purified very-long-chain acyl-CoA synthetase from rat liver peroxisomes.