Α-Ketobutyric acid

α-Ketobutyric acid is an organic compound with the formula CH₃CH₂C(O)CO₂H. It is a colorless solid that melts just above room temperature. Its conjugate base α-ketobutyrate is the predominant form found in nature (near neutral pH). It results from the lysis of cystathionine. It is also one of the degradation products of threonine, produced by the catabolism of the amino acid by threonine dehydratase. It is also produced by the degradation of homocysteine and the metabolism of methionine.

α-Ketobutyric acid

Names
Preferred IUPAC name 2-Oxobutanoic acid
Identifiers
CAS Number	600-18-0 Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:30831 Y
ChEMBL	ChEMBL171246 Y
ChemSpider	57 Y
DrugBank	DB04553 Y
ECHA InfoCard	100.009.080
EC Number	209-986-9
KEGG	C00109 Y
MeSH	Alpha-ketobutyric+acid
PubChem CID	58
UNII	B92RB6HY1A Y
CompTox Dashboard (EPA)	DTXSID9060524
InChI InChI=1S/C4H6O3/c1-2-3(5)4(6)7/h2H2,1H3,(H,6,7) Y Key: TYEYBOSBBBHJIV-UHFFFAOYSA-N Y InChI=1/C4H6O3/c1-2-3(5)4(6)7/h2H2,1H3,(H,6,7) Key: TYEYBOSBBBHJIV-UHFFFAOYAT
SMILES O=C(C(=O)O)CC
Properties
Chemical formula	C4H6O3
Molar mass	102.089 g/mol
Appearance	colorless solid
Melting point	33 °C (91 °F; 306 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

α-Ketobutyrate is transported into the mitochondrial matrix, where it is converted to propionyl-CoA by branched-chain alpha-keto acid dehydrogenase complex. Further mitochondrial reactions produce succinyl-CoA. This is first through the enzyme mitochondria propionyl-CoA carboxylase with biotin as a cofactor to produce (S)-methylmalonyl-CoA. This is subsequently converted to (R)-methylmalonyl-CoA by mitochondrial methylmalonyl-CoA epimerase. Finally, mitochondrial methylmalonyl-CoA mutase with cofactor adenosylcobalamin produces succinyl-CoA which enters the citric acid cycle.^[1]

Conversion in sotolon in French vin jaune

Vin jaune is marked by the formation of sotolon from alpha-ketobutyric acid.^[2][3]

See also

• Butyric acid
• α-Aminobutyric acid (homoalanine)
• 2-Hydroxybutyric acid (α-hydroxybutyric acid)
• Other oxobutanoic acids
  • 3-Oxobutanoic acid (acetoacetic acid)
  • 4-Oxobutanoic acid (succinic semialdehyde)

References

1. http://smpdb.ca/ ^{[not specific enough to verify]}
2. Pham TT, Guichard E, Schlich P, Charpentier C (1995). "Optimal Conditions for the Formation of Sotolon from α-Ketobutyric Acid in the French 'Vin Jaune'". Journal of Agricultural and Food Chemistry. 43 (10): 2616–2619. doi:10.1021/jf00058a012.
3. Guichard E, Pham TT, Etievant P (1993). "Quantitative Determination of Sotolon in Wines by High-Performance Liquid Chromatography". Chromatographia. 37 (9–10): 539–542. doi:10.1007/BF02275793. S2CID 95494741.