Purification and Characterization of the Trifunctional β-Oxidation Complex from Pig Heart Mitochondria

doi:10.1006/abbi.1993.1348

Archives of Biochemistry and Biophysics

Volume 304, Issue 1, July 1993, Pages 266-271

https://doi.org/10.1006/abbi.1993.1348 Get rights and content

Abstract

The presence of a trifunctional β-oxidation complex in pig heart and its relationship to the known long-chain enoyl-CoA hydratase (EC 4.2.1.74) from pig heart mitochondria were investigated. For this study, the complex was partially purified by chromatography on DEAE-cellulose in the absence of detergents and was purified to near homogeneity in the presence of Triton X-100. Both enzyme preparations contained long-chain specific activities of enoyl-CoA hydratase, L-3-hydroxyacyl-CoA dehydrogenase, and 3-ketoacyl-CoA thiolase but were virtually inactive toward short-chain (C₄) substrates. Both preparations exhibited very low or no activities of Δ³,Δ²-enoyl-CoA isomerase (EC 5.3.3.8) and 2,4-dienoyl-CoA reductase (EC 1.3.1.34). The molecular weights of the two subunits of the pig heart complex were estimated to be 81,000 and 45,000, respectively. The partially purified preparation, obtained in the absence of detergent, was identified as a membranous fraction enriched with respect to the inner mitochondrial membrane. It is concluded that long-chain enoyl-CoA hydratase is a component enzyme of the trifunctional β-oxidation complex which is associated with the inner membrane of pig heart mitochondria.

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Citation Excerpt :
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Regular ArticlePurification and Characterization of the Trifunctional β-Oxidation Complex from Pig Heart Mitochondria

Abstract

Regular Article
Purification and Characterization of the Trifunctional β-Oxidation Complex from Pig Heart Mitochondria