Malonyl-CoA

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Malonyl-CoA
Malonyl-CoA2.svg
Identifiers
ChemSpider
ECHA InfoCard 100.007.596
MeSH Malonyl+CoA
Properties
C24H38N7O19P3S
Molar mass 853.582
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Malonyl-CoA is a coenzyme A derivative of malonic acid.

Functions[edit]

It plays a key role in chain elongation in fatty acid biosynthesis and polyketide biosynthesis.

Fatty acid biosynthesis[edit]

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 bicarbonate,[1] 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).

Polyketide biosynthesis[edit]

MCAT is also involved in bacterial polyketide biosynthesis. The enzyme MCAT together with an acyl carrier protein (ACP), and a polyketide synthase (PKS) and chain-length factor heterodimer, constitutes the minimal PKS of type II polyketides.

Regulation[edit]

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 fatty acids from associating with carnitine by regulating the enzyme carnitine acyltransferase, thereby preventing them from entering the mitochondria, where fatty acid oxidation and degradation occur.

See also[edit]

References[edit]

  1. ^ Nelson D, Cox M (2008) Lehninger principles of biochemistry. 5th Ed: p. 806

External links[edit]