Novel fatty acid beta-oxidation enzymes in rat liver mitochondria. I. Purification and properties of very-long-chain acyl-coenzyme A dehydrogenase

J Biol Chem. 1992 Jan 15;267(2):1027-33.

Abstract

Freeze-thawed rat liver mitochondria were extensively washed with potassium phosphate, pH 7.5, and the residue was extracted with 10 mM potassium phosphate, pH 7.5, 1% (w/v) sodium cholate, 0.5 M KCl. The four beta-oxidation enzyme activities of the washes and the last extract were assayed with substrates of various carbon chain lengths. Our data suggest that the last extract contains a novel acyl-CoA dehydrogenase and long-chain 3-hydroxyacyl-CoA dehydrogenase. A novel acyl-CoA dehydrogenase was purified. The molecular masses of the native enzyme and the subunit were estimated to be 150 and 71 kDa, respectively. One mole of enzyme contained 2 mole of FAD. These properties and immunochemical properties of the enzyme differed from those of three other acyl-CoA dehydrogenases: short-, medium-, and long-chain acyl-CoA dehydrogenases. Carbon chain length specificity of the enzyme differed from that of other acyl-CoA dehydrogenases. The enzyme was active toward CoA esters of long- and very-long-chain fatty acids, but not toward those of medium- and short-chain fatty acids. The specific enzyme activity was greater than 10 times that of long-chain acyl-CoA dehydrogenase when palmitoyl-CoA was used as substrate. We propose the name "very-long-chain acyl-CoA dehydrogenase" for this enzyme.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acyl-CoA Dehydrogenase, Long-Chain / isolation & purification*
  • Acyl-CoA Dehydrogenase, Long-Chain / metabolism
  • Animals
  • Blotting, Western
  • Chromatography, Liquid
  • Detergents
  • Electrophoresis, Polyacrylamide Gel
  • Flavin-Adenine Dinucleotide / metabolism
  • Hydrogen-Ion Concentration
  • Male
  • Mitochondria, Liver / enzymology*
  • Molecular Weight
  • Oxidation-Reduction
  • Rats
  • Rats, Inbred Strains

Substances

  • Detergents
  • Flavin-Adenine Dinucleotide
  • Acyl-CoA Dehydrogenase, Long-Chain