In enzymology, 4-aminobutyrate transaminase (EC 2.6.1.19), also called GABA transaminase or 4-aminobutyrate aminotransferase, or GABA-T, is an enzyme that catalyzes the chemical reaction: 4-aminobutanoate + 2-oxoglutarate succinate semialdehyde + L-glutamate Thus, the two substrates of this enzyme are 4-aminobutanoate (GABA) and 2-oxoglutarate. The two products are succinate semialdehyde and L-glutamate. This enzyme is found in prokaryotes, plants, fungi, and animals (including humans). Pigs have often been used when studying how this protein may work in humans.