At least three acyl-CoA synthases, each specific for a particular size of fatty acid, exist: acetyl -CoA synthase acts on acetate and other low-molecular-weight carboxylic acids, medium-chain acyl-CoA synthase on fatty acids with 4–11 carbon atoms, and acyl-CoA …
Relative reactivity of biologically relevant acyl groups Acyl-CoA thioesters did not inhibit the uptake of [2-(14)C]pyruvate or D-[1-(14)C]glucose into plastids.
FLX undergoes highly stereoselective chiral inversion mediated through the FLX- S -acyl-CoA thioester (FLX-CoA) in favor of the ( R )-(−)-isomer.
B) Allosteric kinetic data of CpFAS1-R towards C26:0 hexacosanoyl CoA. They are employed as acyl carriers that facilitate the transfer of acyl groups to lipids and proteins. However, neither is as reactive as an acid chloride or acid anhydride. Quantification of medium‐ and long‐chain acyl‐CoAs represents a significant bioanalytical challenge because of their instability. Formation of xenobiotic acyl CoAs may disrupt this pathway by sequestering either CoA or carnitine or by inhibiting the enzyme involved in β-oxidation (101). The purification of the fatty acyl coenzyme A by reverse-phase chromatography is described. 1982.23: 1368-1373. This inhibition was attributable to the synthesis of acyl-CoA thioesters, predominantly oleoyl-CoA and palmitoyl-CoA, by long-chain fatty acid-CoA ligase (EC 6.2.1.3) from endogenous fatty acids in the plastid preparations. Thus, intracellularly formed acyl-CoAs of xenobiotic carboxylic acids may react covalently with endogenous proteins and potentially lead to adverse effects. This inhibition was attributable to the synthesis of acyl-CoA thioesters, predominantly oleoyl-CoA and palmitoyl-CoA, by long-chain fatty acid-CoA ligase (EC 6.2.1.3) from endogenous fatty acids in the plastid preparations. Hertz R(1), Magenheim J, Berman I, Bar-Tana J.
The data support the proposed four-step reaction mechanism of ACDs, coupling acyl-CoA thioesters with ATP synthesis. A) Substrate preference of CpFAS-R as displayed by activity.
Title: Xenobiotic Acyl Glucuronides and Acyl CoA Thioesters as Protein- Reactive Metabolites With the Potential to Cause Idiosyncratic Drug Reactions VOLUME: 3 ISSUE: 4 Author(s):Urs A. Boelsterli Affiliation:HepaTox Consulting, P.O.
They are employed as acyl carriers, assisting with the transfer of acyl groups such as fatty acids from one acyl X substrate to another. B) Allosteric kinetic data of CpFAS1-R towards C26:0 hexacosanoyl CoA.
Others have been implicated in carbon−carbon bond formation and cleavage as well as the hydrolysis of thioesters.
Fatty acyl-CoA thioesters are ligands of hepatic nuclear factor-4alpha. Box14, CH-4148 Pfeffingen, Switzerland Keywords:xenobiotic acyl glucuronide, acyl coa thioester, protein reactive metabdite, I diosyhcratic reaction Recall from Section 21.2 that thioesters and acyl phosphates are the most reactive among the biologically relevant acyl groups. On the inner mitochondrial membrane, acyl-carnitine esters are converted into acyl CoA thioesters by CAT II, subsequently oxidizing fatty acids and generating acetyl CoA and ATP (100). acyl-coenzyme A thioesters. Inset shows the OD 340 changes during the time course of reactions. Supplementary key words fatty acyl-CoA synthetase fluorescent fatty acyl-CoA immobilized enzymes A variety of chemical and enzymatic methods have been developed to synthesize fatty acyl-CoA thioesters. Absolute quantification of intracellular coenzyme A (CoA), coenzyme A disulfide, and short-chain acyl-coenzyme A thioesters was addressed by developing a tailored metabolite profiling method based on liquid chromatography in combination with tandem mass spectrometric detection (LC-MS/MS). A) Substrate preference of CpFAS-R as displayed by activity.
Energetically, CoA thioesters have high phosphoryl transfer potential (i.e., a high negative free energy change associated with breaking the C–S bond of the thioester) that facilitates driving the acyl transfer reaction in which it participates toward completion. Author information: (1)Department of Human Nutrition and Metabolism, Faculty of Medicine, Hebrew University, Jerusalem. The chemical syntheses (1-7) are relatively simple, but Fatty-acyl-CoA thioesters inhibit recruitment of steroid receptor co-activator 1 to α and γ isoforms of peroxisome-proliferator-activated receptors by competing with agonists Reactivity of thioesters and acyl phosphates. Structures of pimeloyl-CoA synthetase (BioW) provide insights into its catalytic mechanism and how it selects the correct length of dicarboxylic acid …
The chemical reactivity of acyl-CoA thioesters toward nucleophiles has been demonstrated in several recent studies. Acyl-CoA thioesters did not inhibit the uptake of [2-(14)C]pyruvate or D-[1-(14)C]glucose into plastids. Alcohol-forming fatty acyl-CoA reductases (FAR) catalyze the reduction of activated acyl groups to fatty alcohols that can be esterified with acyl-CoA thioesters forming wax esters. Activity of recombinant CpFAS1-R as assayed using long to very long chain fatty acyl-CoA thioesters as substrates and NADPH as cofactor.