Propionyl-CoA

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Propionyl-CoA
Identifiers
CAS number	[317-66-8]
PubChem	1033
MeSH	propionyl-coenzyme+A
Properties
Molecular formula	C24H40N7O17P3S
Molar mass	823.599
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

Propionyl-CoA is a coenzyme A derivative of propionic acid.

Contents 1 Metabolism in animals 1.1 Production 1.2 Metabolic fate 2 Metabolism in plants and insects 3 References

[edit] Metabolism in animals

[edit] Production

There are several different ways in which it is formed:

• It is formed as a product of beta-oxidation of odd-chain fatty acids, which occur in meat of ruminant animals.

• It is also a product of metabolism of isoleucine and valine.

• It is a product of alpha-ketobutyric acid, which in turn is a product of digestion of threonine and methionine.

[edit] Metabolic fate

In mammals, propionyl-CoA is converted to (S)-methylmalonyl-CoA by propionyl-CoA carboxylase, a biotin-dependent enzyme also requiring bicarbonate and ATP.

This product is converted to (R)-methylmalonyl-CoA by methylmalonyl-CoA racemase.

(R)-Methylmalonyl-CoA is converted to succinyl-CoA by methylmalonyl-CoA mutase, an enzyme requiring cobalamin to catalyze the carbon-carbon bond migration.

A defect in methylmalonyl-CoA mutase enzyme results in methylmalonic aciduria, a dangerous disorder that causes a lowering of blood pH.

[edit] Metabolism in plants and insects

In plants and insects propionyl-CoA is metabolized to acetate in a very different way, similar to beta oxidation.

Not all details of this pathway have been worked out, but it appears to involve formation of acrylyl-CoA, then 3-hydroxypropionyl-CoA.

This is metabolized with loss of carbon 1 of 3-hydroxypropionyl-CoA as carbon dioxide, while carbon 3 becomes carbon 1 of acetate.

[edit] References

• Halarnkar P, Blomquist G (1989). "Comparative aspects of propionate metabolism". Comp. Biochem. Physiol., B 92 (2): 227–31. doi:10.1016/0305-0491(89)90270-8. PMID 2647392. 

v • d • e Amino acid metabolism metabolic intermediates K→acetyl-CoA lysine→ Saccharopine - Allysine - Alpha-aminoadipate - Alpha-ketoadipic acid - Glutaryl-CoA - Glutaconyl-CoA - Crotonyl-CoA - Beta-hydroxybutyryl-CoA leucine→ Alpha-ketoisocaproic acid - Isovaleryl-CoA - 3-Methylcrotonyl-CoA - 3-Methylglutaconyl-CoA - HMG-CoA tryptophan→alanine→ N'-Formylkynurenine - Kynurenine - Anthranilic acid - 3-hydroxykynurenine - 3-Hydroxyanthranilic acid - 2-Amino-3-carboxymuconic semialdehyde - 2-Aminomuconic semialdehyde - 2-Aminomuconic acid - Glutaryl-CoA G→glutamate histidine→ Urocanic acid - Imidazol-4-one-5-propionic acid - Formiminoglutamic acid - Glutamate-1-semialdehyde proline→ 1-Pyrroline-5-carboxylic acid arginine→ Ornithine - Putrescine - Agmatine G→propionyl-CoA methionine→ S-Adenosyl methionine - S-Adenosyl-L-homocysteine - Homocysteine - Cystathionine - alpha-Ketobutyric acid isoleucine→ 2,3-Dihydroxy-3-methylpentanoic acid - 2-Methylbutyryl-CoA - Tiglyl-CoA - 2-methylacetoacetyl-CoA valine→ Alpha-ketoisovalerate - Isobutyryl-CoA - Methacrylyl-CoA - 3-Hydroxyisobutyryl-CoA - 3-Hydroxyisobutyrate - 2-methyl-3-oxopropanoate threonine→ Alpha-ketobutyric acid propionyl-CoA→ Methylmalonyl-CoA G→fumarate phenylalanine→tyrosine→ 4-Hydroxyphenylpyruvic acid - Homogentisic acid - 4-Maleylacetoacetate Other cysteine+glutamate→glutathione gamma-Glutamylcysteine glycine→creatine Glycocyamine - Phosphocreatine - Creatinine Other Glycerate 3-phosphate (serine) - Cysteine sulfinic acid see also enzymes, disorders