Diaminobutyrate-2-oxoglutarate transaminase () is an enzyme that catalyzes the chemical reaction
The two substrates of this enzyme are L-aspartic-4-semialdehyde and glutamic acid. Its products are the (S) enantiomer of 2,4-diaminobutyric acid (DABA) and α-ketoglutaric acid. The product DABA in bacteria is subsequently converted to the osmoprotectant, ectoine. In other organisms including Acinetobacter baumannii and Haemophilus influenzae it is the precursor to 1,3-diaminopropane.
This enzyme belongs to the family of transferases, specifically the transaminases, which transfer nitrogenous groups. The systematic name of this enzyme class is L-2,4-diaminobutanoate:2-oxoglutarate 4-aminotransferase. Other names in common use include L-2,4-diaminobutyrate:2-ketoglutarate 4-aminotransferase, 2,4-diaminobutyrate 4-aminotransferase, diaminobutyrate aminotransferase, DABA aminotransferase, DAB aminotransferase, EctB, diaminibutyric acid aminotransferase, and L-2,4-diaminobutyrate:2-oxoglutarate 4-aminotransferase.
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