Preliminary evidence for the existence of specific functional assemblies between enzymes of the beta-oxidation pathway and the respiratory chain.
The electron-transferring flavoprotein (ETF) has been detected in two large soluble-protein complexes partially purified from sonicated porcine liver mitochondria. Size-exclusion chromatography and sucrose-density ultracentrifugation suggested molecular masses in the region of 390 to 420 kDa for the two complexes. Activities of medium-chain acyl-CoA dehydrogenase, sarcosine dehydrogenase and ETF:ubiquinone oxidoreductase were also detected. No evidence of oxidative-phosphorylation properties was obtained. Treatment with antimycin A inhibited the activity of both complexes. Pyridine haemochromogens, prepared from the partially purified species, show the presence of cytochrome proteins. The possible composition of these complexes and their relationship to the electron transport chain are discussed.
Parker
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A
Department of Biochemistry, University College Dublin, Belfield, Dublin 4, Ireland.
Engel
P C
PC
D042964:Acyl-CoA Dehydrogenase; D044944:Acyl-CoA Dehydrogenases / Q000737:chemistry / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D019069:Cell Respiration / Q000502:physiology; D002850:Chromatography, Gel; D017936:Cytochrome a Group / Q000032:analysis / Q000378:metabolism; D004579:Electron Transport; D044927:Electron-Transferring Flavoproteins; D004798:Enzymes / Q000378:metabolism*; D005420:Flavoproteins / Q000378:metabolism*; D007506:Iron-Sulfur Proteins; D008930:Mitochondria, Liver / Q000378:metabolism*; D008970:Molecular Weight; D009097:Multienzyme Complexes / Q000737:chemistry / Q000378:metabolism; D010084:Oxidation-Reduction; D000587:Oxidoreductases Acting on CH-NH Group Donors; D010089:Oxidoreductases, N-Demethylating / Q000302:isolation & purification / Q000378:metabolism; D010743:Phospholipids / Q000737:chemistry / Q000378:metabolism; D011725:Pyridines / Q000032:analysis; D050892:Sarcosine Dehydrogenase; D013552:Swine; D014461:Ultracentrifugation / Q000379:methods
D017936:Cytochrome a Group; D044927:Electron-Transferring Flavoproteins; D004798:Enzymes; D005420:Flavoproteins; D007506:Iron-Sulfur Proteins; D009097:Multienzyme Complexes; D010743:Phospholipids; D011725:Pyridines; D044944:Acyl-CoA Dehydrogenases; D042964:Acyl-CoA Dehydrogenase; D000587:Oxidoreductases Acting on CH-NH Group Donors; D010089:Oxidoreductases, N-Demethylating; C023120:electron-transferring-flavoprotein dehydrogenase; D050892:Sarcosine Dehydrogenase