Arachidonoyl-CoA synthetase was solubilized from a particulate fraction of calf brain and human platelets using 1% Nonidet P-40 and 10 mM EDTA. Arachidonoyl-CoA synthetase from both preparations was separated from nonspecific (long chain) acyl-CoA synthetase (EC 6.2.1.3) by chromatography on hydroxylapatite. To further substantiate that the two acyl-CoA synthetases are distinct proteins, we sol...

Most serine cycle methylotrophic bacteria lack isocitrate lyase and convert acetyl coenzyme A (acetyl-CoA) to glyoxylate via a novel pathway thought to involve butyryl-CoA and propionyl-CoA as intermediates. In this study we have used a genome analysis approach followed by mutation to test a number of genes for involvement in this novel pathway. We show that methylmalonyl-CoA mutase, an R-speci...

The effect of CoA and fatty acyl-CoA esters on Ca2+ fluxes has been studied in isolated liver microsomes and in digitonin-permeabilized hepatocytes. When microsomes were loaded with increasing concentrations of Ca2+ (6-29 nmol/mg of protein), the extent to which CoA and palmitoyl-CoA released Ca2+ increased. At 23 nmol of Ca2+/mg of protein, half-maximal [CoA] and [palmitoyl-CoA] were 35 and 50...

Dormant spores of Bacillus megaterium were found to contain approximately 850 pmol of coenzyme A (CoA) per milligram of dry weight. Of this total, less than 1.5% was acetyl-CoA, 25% was CoA-disulfide, 43% was in disulfide linkage to protein, and the remainder was the free thiol. Dormand spores of Bacillus cereus and Clostridium bifermentans contained 700 and 600 pmol of CoA per milligram of dry...

Rats were maintained on a riboflavin-deficient diet or on a diet containing clofibrate (0.5%, w/w). The activities of the mitochondrial FAD-dependent straight-chain acyl-CoA dehydrogenases (butyryl-CoA, octanoyl-CoA and palmitoyl-CoA) and the branched-chain acyl-CoA dehydrogenases (isovaleryl-CoA and isobutyryl-CoA) involved in the degradation of branched-chain acyl-CoA esters derived from bran...

Palmitoyl coenzyme A instantly and reversibly inhibited the electron transport-linked phosphorylation of ADP coupled to the oxidation of various substrates by rat heart mitochondria. The inhibitory effectiveness of pahnitoyl-CoA was dependent on mitochondrial as well as ADP concentration. Removal of palmitoyl-CoA, such as by its oxidation following (-)-carnitine addition, led to a restoration o...

1. The activities of acetoacetyl-CoA thiolase, hydroxymethylglutaryl-CoA synthase and lyase and acetoacetyl-CoA deacylase were measured in homogenates of samples of liver, rumen epithelium (long papillae), kidney and lactating mammary gland derived from slaughtered cows. 2. The activities of the four enzymes in bovine liver were similar to the activities previously reported for the correspondin...

The central nervous system mediates energy balance (energy intake and energy expenditure) in the body; the hypothalamus has a key role in this process. Recent evidence has demonstrated an important role for hypothalamic malonyl CoA in mediating energy balance. Malonyl CoA is generated by the carboxylation of acetyl CoA by acetyl CoA carboxylase and is then either incorporated into long-chain fa...

The intracellular concentration of free unbound acyl-CoA esters is tightly controlled by feedback inhibition of the acyl-CoA synthetase and is buffered by specific acyl-CoA binding proteins. Excessive increases in the concentration are expected to be prevented by conversion into acylcarnitines or by hydrolysis by acyl-CoA hydrolases. Under normal physiological conditions the free cytosolic conc...

Three straight chain acyl-CoA dehydrogenases were purified to apparent homogeneity from bovine liver using 40-70% (NH4)2SO4 precipitation, gel filtration, DEAE-cellulose column chromatography, and preparative electrophoresis. Separation of the acyl-CoA dehydrogenases by these procedures has been efficiently monitored by two newly developed analytical methods: (i) native staining of acyl-CoA deh...