Malonyl-CoA

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Malonyl-CoA
Identifiers
CAS number	[524-14-1]
PubChem	869
MeSH	Malonyl+CoA
Properties
Molecular formula	C24H38N7O19P3S
Molar mass	853.582
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

Malonyl-CoA is a coenzyme A derivative which plays a key role in chain elongation in fatty acid biosynthesis and polyketide biosynthesis. In the former, it provides 2-carbon units to fatty acids and commits them to fatty acid chain synthesis.

Malonyl-coA is formed in the metabolism from the carboxylation of acetyl-coA by the enzyme acetyl-coA carboxylase. One molecule of acetyl co-A is joined with a molecule of carbon dioxide, requiring energy rendered from 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).

Controversy still exists 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.

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: the association of coenzyme A with carnitine. This step permits coenzyme A to enter the mitochondria and regulation prevents simultaneous synthesis and breakdown of fatty acids.

[edit] See Also

• Malonyl-CoA decarboxylase deficiency