Malonyl-CoA 2468995 210656040 2008-05-06T21:01:56Z Rockfang 5403270 changing stub name per [[Wikipedia:Stub_types_for_deletion/Log/2008/March/19|SfD]] , typos fixed: degredation → degradation using [[Project:AutoWikiBrowser|AWB]] {{Chembox new | ImageFile = Malonyl-CoA2.svg‎ | ImageSize = | IUPACName = | OtherNames = | Section1 = {{Chembox Identifiers | CASNo = 524-14-1 | PubChem = 869 | SMILES = | MeSHName = Malonyl+CoA }} | Section2 = {{Chembox Properties | Formula = C<sub>24</sub>H<sub>38</sub>N<sub>7</sub>O<sub>19</sub>P<sub>3</sub>S | MolarMass = 853.582 | Appearance = | Density = | MeltingPt = | BoilingPt = }} | Section3 = {{Chembox Hazards | Solubility = | MainHazards = | FlashPt = | Autoignition = }} }} '''Malonyl-CoA''' is a [[coenzyme A]] derivative. ==Functions== It plays a key role in chain elongation in [[fatty acid]] biosynthesis and [[polyketide]] biosynthesis. ===Fatty acid biosynthesis=== In the former, it provides 2-carbon units to fatty acids and commits them to fatty acid chain synthesis. Malonyl-CoA is formed by carboxylating [[acetyl-CoA]] using the enzyme [[acetyl-CoA carboxylase]]. One molecule of acetyl-CoA joins with a molecule of [[carbon dioxide]], requiring energy rendered from [[adenosine triphosphate|ATP]]. Malonyl-CoA is utilised in fatty acid biosynthesis by the enzyme '''malonyl coenzyme A:[[acyl carrier protein]] transacylase''' (MCAT). MCAT serves to transfer [[malonate]] from malonyl-CoA to the terminal [[thiol]] of ''holo''-[[acyl carrier protein]] (ACP). ===Polyketide biosynthesis=== Controversy still exists as to whether MCAT is also involved in bacterial [[polyketide]] biosynthesis, however there is evidence that the acyl carrier protein from a variety of bacterial polyketide synthases is capable of self-malonylation in the presence of malonyl-CoA. ===Regulation=== Malonyl-CoA is a highly-regulated molecule in fatty acid synthesis; as such, it inhibits the rate-limiting step in [[beta-oxidation]] of fatty acids. Malonyl CoA inhibits [[coenzyme A]] from associating with [[carnitine]], thereby preventing coenzyme A from entering the [[mitochondria]] where [[fatty acid oxidation]] and degradation occur. ==See also== *[[Malonyl-CoA decarboxylase]] *[[Malonyl-CoA decarboxylase deficiency]] {{metabolism-stub}} [[Category:Metabolism]] [[Category:Thioesters]] [[Category:Coenzymes]] [[de:Malonyl-CoA]] [[es:Malonil-CoA]] [[ja:マロニルCoA]]