Metabolism of acetyl-CoA by isolated peroxisomal fractions: formation of acetate and acetoacetyl-CoA.
Liver peroxisomal fractions, isolated from rats treated with clofibrate, were shown to hydrolyze added [1-14C]acetyl-CoA to free [1-14C]acetate. [1-14C]Acetyl-CoA was, however, also converted to [14C]acetoacetyl-CoA. This reaction was inhibited by added ATP and by solubilization of the peroxisomes. The effect of ATP on synthesis of [14C]acetoacetyl-CoA was likely due to ATP-dependent stimulation of acetyl-CoA hydrolase (EC 3.1.2.1) activity. The inhibitory effect due to solubilizing conditions of incubation remains unexplained. During peroxisomal beta-oxidation of [1-14C]palmitoyl-CoA, [1-14C]acetyl-CoA, [1-14C]acetate, and [14C]acetoacetyl-CoA were shown to be produced. Possible metabolic implications of peroxisomal acetoacetyl-CoA synthesis are discussed.
Department of Physiology and Biochemistry, Dental School, University of Oslo, Norway.
R
R
Hovik
B
B
Brodal
K
K
Bartlett
H
H
Osmundsen
D000085:Acetates / Q000378:metabolism*; D000105:Acetyl Coenzyme A / Q000096:biosynthesis / Q000378:metabolism*; D000104:Acetyl-CoA Hydrolase / Q000378:metabolism; D000214:Acyl Coenzyme A; D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D008099:Liver / Q000378:metabolism; D008297:Male; D008830:Microbodies / Q000187:drug effects / Q000378:metabolism*; D010171:Palmitoyl Coenzyme A / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D012995:Solubility; D013347:Subcellular Fractions / Q000378:metabolism
D000085:Acetates; D000214:Acyl Coenzyme A; D011506:Proteins; C010667:acetoacetyl CoA; D010171:Palmitoyl Coenzyme A; D000105:Acetyl Coenzyme A; D000255:Adenosine Triphosphate; D000104:Acetyl-CoA Hydrolase