Intracellular localization of long-chain acyl-coenzyme A hydrolase and acyl-L-carnitine hydrolase in brown adipose tissue from guinea pigs.
The activities of long-chain acyl-CoA hydrolase (palmitoyl-CoA hydrolase, EC 3.1.2.2) and long-chain acyl-L-carnitine hydrolase, EC 3.1.1.28) in brown adipose tissue from cold-exposed and control guinea pigs were studied. Mitochondria from cold-exposed animals hydrolysed 21 nmol of palmitoyl-CoA/min per mg of protein and 1.3 nmol of palmitoyl-L-carnitine/min per mg of protein, and the specific activities were respectively 2 and 5 times as high in cold-exposed as in control animals. The subcellular-localization studies showed that both the long-chain acyl-CoA hydrolase and long-chain acyl-L-carnitine hydrolase were localized in the mitochondria. A location also in the soluble fraction cannot be excluded. The long-chain acyl-CoA hydrolase activity was doubled when the mitochondria were disrupted; this indicates that the enzyme is localized in the matrix compartment.
D002001:Adipose Tissue, Brown / Q000201:enzymology*; D000818:Animals; D002265:Carboxylic Ester Hydrolases / Q000378:metabolism*; D003080:Cold Temperature; D006168:Guinea Pigs; D008928:Mitochondria / Q000201:enzymology; D010170:Palmitoyl-CoA Hydrolase / Q000378:metabolism*; D010172:Palmitoylcarnitine; D013347:Subcellular Fractions / Q000201:enzymology; D013869:Thiolester Hydrolases / Q000378:metabolism*
D010172:Palmitoylcarnitine; D002265:Carboxylic Ester Hydrolases; D013869:Thiolester Hydrolases; D010170:Palmitoyl-CoA Hydrolase