Characterization and isolation of enzymes that hydrolyze short-chain acyl-CoA in rat-liver mitochondria.
In this study we investigated the presence of short-chain acyl-CoA hydrolases in rat liver mitochondria. One acetyl-CoA-hydrolyzing enzyme with a molecular mass of about 48 kDa was purified to apparent homogeneity as judged by SDS/PAGE. Immunoprecipitation experiments with antibodies raised to the purified protein showed that this enzyme corresponds to a minor portion of the total mitochondrial acetyl-CoA hydrolase activity, most (about 90%) of the total activity being due to an enzyme which was labile and required Triton X-100 for its stability. Neither of these acetyl-CoA-hydrolyzing enzymes appeared to be induced by treatment of rats with di(2-ethylhexyl)phthalate, a peroxisome proliferator which mediates induction of several cytosolic and mitochondrial long-chain acyl-CoA thioesterases. In addition, an enzyme that hydrolyzed acetoacetyl-CoA was partially purified; it was induced about 3.5-fold by di(2-ethylhexyl)phthalate treatment. In conclusion, these results demonstrate that rat liver mitochondria contain several enzymes capable of hydrolyzing short-chain acyl-CoA, indicating that regulation of the metabolism of short-chain acyl-CoAs and formation of ketone bodies, could be complex.
Svensson
L T
LT
Department of Medical Laboratory Sciences and Technology, Karolinska Institutet, Huddinge University Hospital, Sweden.
Kilpeläinen
S H
SH
Hiltunen
J K
JK
Alexson
S E
SE
D000104:Acetyl-CoA Hydrolase / Q000302:isolation & purification / Q000378:metabolism; D000214:Acyl Coenzyme A / Q000378:metabolism*; D000818:Animals; D002458:Cell Fractionation; D002845:Chromatography; D002850:Chromatography, Gel; D017886:Durapatite; D004591:Electrophoresis, Polyacrylamide Gel; D006868:Hydrolysis; D008297:Male; D008930:Mitochondria, Liver / Q000201:enzymology*; D008970:Molecular Weight; D051381:Rats; D017207:Rats, Sprague-Dawley; D013379:Substrate Specificity
D000214:Acyl Coenzyme A; D017886:Durapatite; D000104:Acetyl-CoA Hydrolase