Beta-oxidation of long-chain fatty acids by human fibroblasts: evidence for a novel long-chain acyl-coenzyme A dehydrogenase.
Fibroblasts from patients with long-chain acyl-CoA dehydrogenase deficiency were found to oxidize [1-14C]linoleate at an average rate of 60% of normal but [9,10(n)-3H]myristate at an average rate of only 37% of normal, a relationship reverse from that predicted by the chain-length specificities of the three known straight-chain mitochondrial acyl-CoA dehydrogenases. The residual long-chain beta-oxidative activity was found to be mitochondrial and associated with the accumulation of tetradecadienoate (C14:2w6) when the mutant fibroblasts were incubated with 100 mumol/L linoleate (C18:2w6) or eicosadienoate (C20:2w6). The results suggest the presence in human fibroblasts of a novel acyl-CoA dehydrogenase with activity toward 15 to 20 carbon-length fatty acids.
Kelley
R I
RI
Kennedy Institute, Johns Hopkins University School of Medicine, Baltimore, MD.
D042964:Acyl-CoA Dehydrogenase; D044942:Acyl-CoA Dehydrogenase, Long-Chain / Q000172:deficiency / Q000378:metabolism*; D002250:Carbon Radioisotopes; D002460:Cell Line; D002478:Cells, Cultured; D005347:Fibroblasts / Q000201:enzymology; D006801:Humans; D007700:Kinetics; D019787:Linoleic Acid; D008041:Linoleic Acids / Q000378:metabolism*; D019814:Myristic Acid; D009227:Myristic Acids / Q000378:metabolism*; D010084:Oxidation-Reduction; D012867:Skin / Q000201:enzymology*; D013379:Substrate Specificity; D014316:Tritium
D002250:Carbon Radioisotopes; D008041:Linoleic Acids; D009227:Myristic Acids; D019814:Myristic Acid; D014316:Tritium; D019787:Linoleic Acid; D042964:Acyl-CoA Dehydrogenase; D044942:Acyl-CoA Dehydrogenase, Long-Chain