2-Oxobutanoate
2-Ketobutyric acid, also known as alpha-ketobutyrate or 2-oxobutyrate, belongs to the class of organic compounds known as short-chain keto acids and derivatives. These are keto acids with an alkyl chain the contains less than 6 carbon atoms. 2-Ketobutyric acid is a substance that is involved in the metabolism of many amino acids (glycine, methionine, valine, leucine, serine, threonine, isoleucine) as well as propanoate metabolism and C-5 branched dibasic acid metabolism. It is also one of the degradation products of threonine. It can be converted into propionyl-CoA (and subsequently methylmalonyl CoA, which can be converted into succinyl CoA, a citric acid cycle intermediate), and thus enter the citric acid cycle. More specifically, 2-ketobutyric acid is a product of the lysis of cystathionine.
| ID | EC Number | Name |
|---|---|---|
| KEGG:R00654 | 4.4.1.11 | L-methionine methanethiol-lyase (deaminating;2-oxobutanoate-forming) |
| KEGG:R00993 | 1.2.3.- | 2-oxobutanoate:oxygen 2-oxidoreductase (phosphorylating) |
| KEGG:R00994 | 1.1.1.85 | (2R,3S)-3-methylmalate:NAD+ oxidoreductase |
| KEGG:R00995 | 4.1.1.112 | methyloxaloacetate carboxy-lyase (2-oxobutanoate-forming) |
| KEGG:R00996 | 4.3.1.19 | L-threonine ammonia-lyase (2-oxobutanoate-forming) |
| KEGG:R00997 | 3.5.99.7 | 1-aminocyclopropane-1-carboxylate aminohydrolase (isomerizing); |
| KEGG:R00998 | 2.3.3.6 | acetyl-CoA:2-oxobutanoate C-acetyltransferase (thioester-hydrolysing, carboxymethyl-forming); |
| KEGG:R00999 | 2.5.1.48 | O-succinyl-L-homoserine succinate-lyase (deaminating; 2-oxobutanoate-forming) |
| KEGG:R01000 | 1.1.1.27 | 2-hydroxybutyrate:NAD+ oxidoreductase |
| KEGG:R01001 | 4.4.1.1 | L-cystathionine cysteine-lyase (deaminating; 2-oxobutanoate-forming) |
| KEGG:R01199 | 1.2.7.1 | 2-oxobutanoate:ferredoxin 2-oxidoreductase (CoA-propanoylating) |
| KEGG:R01283 | 4.4.1.2 | L-homocysteine hydrogen-sulfide-lyase (deaminating; 2-oxobutanoate-forming) |
| KEGG:R04673 | 2.2.1.6 | (S)-2-aceto-2-hydroxybutanoate pyruvate-lyase (carboxylating) |
| KEGG:R04770 | 4.4.1.1 | selenomethionine methanethiol-lyase (deaminating) |
| KEGG:R04930 | 4.4.1.1 | selenocystathionine lysteine-lyase (deaminating) |
| KEGG:R05840 | C00266 + C00109 + C01401<=>C00314 | |
| KEGG:R06987 | 2.3.1.54 | propanoyl-CoA:formate C-propanoyltransferase |
| KEGG:R08637 | 2-aminobut-2-enoate aminohydrolase (spontaneous) | |
| KEGG:R08648 | 2.2.1.6 | pyruvate:2-oxobutanoate acetaldehydetransferase (decarboxylating) |
| KEGG:R10991 | 2.6.1.42 | 2-aminobutanoate:2-oxoglutarate aminotransferase |
| KEGG:R10992 | 2.6.1.44 | L-alanine:2-oxobutanoate aminotransferase |
| KEGG:R10996 | 1.2.4.4 | C00109 + C00068<=>C21017 + C00011 |
| KEGG:R11098 | 3.5.99.10 | 2-iminobutanoate aminohydrolase |
| BioCyc:KETOBUTFORMLY-RXN | 2.3.1.- | 2-OXOBUTANOATE + CO-A --> PROPIONYL-COA + FORMATE |
| BioCyc:ACETOOHBUTSYN-RXN | 2.2.1.6 | 2-aceto-2-hydroxy-butyrate synthase |
| BioCyc:RXN-15123 | 3.5.99.10 | CPD-16013 + WATER + PROTON --> 2-OXOBUTANOATE + AMMONIUM |
| BioCyc:THREDEHYD-RXN | 4.3.1.19 | THR --> 2-OXOBUTANOATE + AMMONIUM |
| BioCyc:TRANS-RXN0-558 | 2-OXOBUTANOATE --> 2-OXOBUTANOATE | |
| BioCyc:RXN0-7227 | ETR-Quinones + CPD-3564 --> ETR-Quinols + 2-OXOBUTANOATE | |
| BioCyc:METBALT-RXN | 4.3.1.- | O-SUCCINYL-L-HOMOSERINE + WATER --> PROTON + 2-OXOBUTANOATE + SUC + AMMONIUM |