2,4-Diaminobutyric acid, also known as DABA, is GABA-T non-competitive inhibitor and a GABA reuptake inhibitor. In many bacteria, its (S) enantiomer is a natural product which is an intermediate to the osmoprotectant, ectoine.
Mechanism of action DABA's main action is being an inhibitor of GABA transaminase, an enzyme that converts GABA back to glutamate. When the enzyme is inhibited, this conversion cannot happen, therefore, GABA levels are elevated.
It has also been observed that 2,4-diaminobutyric acid is a GABA reuptake inhibitor. This action further elevates levels of GABA.
Toxicity In addition to being a neurotoxin, DABA can also cause liver damage.
Its potential as an anticonvulsant is unclear, it has been shown to have anticonvulsant properties against picrotoxin, but over the long term, it could paradoxically cause convulsions.
Biosynthesis and metabolism The (S) enantiomer of DABA is a natural product which is an intermediate in many bacteria to the osmoprotectant, ectoine. It is produced by the enzyme diaminobutyrate-2-oxoglutarate transaminase that produces it from L-aspartic-4-semialdehyde and glutamic acid. It has been found in Halomonas elongata and Bacillus pasteurii.
In other organisms including Acinetobacter baumannii and Haemophilus influenzae, DABA is the precursor to 1,3-diaminopropane.
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