4-aminobutyrate—2-oxoglutarate transaminase (GABA transaminase (GABA-T))

4-aminobutyrate—2-oxoglutarate transaminase (GABA transaminase, GABA-T) is a pyridoxal phosphate-dependent enzyme involved in the catabolism of gamma-aminobutyric acid (GABA), the principal inhibitory neurotransmitter in the central nervous system[1][3][5]. It catalyzes the transfer of the amino group from GABA to 2-oxoglutarate, producing succinate semialdehyde and L-glutamate[2][3][5]. The enzyme is crucial for terminating GABAergic neurotransmission and maintaining neurotransmitter balance. It is targeted by the antiepileptic drug vigabatrin, used to increase GABA concentrations in the brain by inhibiting GABA transaminase, which is therapeutically relevant in epilepsy and certain movement disorders[1]. Genetic deficiency of this enzyme leads to a rare, severe neurological disorder characterized by psychomotor retardation, seizures, and other developmental abnormalities[1][3]. The enzyme is found in a diverse range of organisms, including humans, and functions as a mitochondrial protein in neurons and other tissues[3][7].

Other names

4-aminobutyrate aminotransferaseGABA transaminasegamma-amino-N-butyrate transaminasebeta-alanine—oxoglutarate aminotransferaseGABA aminotransferaseGABA-alpha-ketoglutarate aminotransferaseAminobutyrate aminotransferase

Irreversible inhibition of GABA transaminase by drugs such as vigabatrin, leading to increased brain GABA levels