4-aminobutyrate---pyruvate transaminase (EC 2.6.1.96, aminobutyrate aminotransferase, gamma-aminobutyrate aminotransaminase, gamma-aminobutyrate transaminase, gamma-aminobutyric acid aminotransferase, gamma-aminobutyric acid pyruvate transaminase, gamma-aminobutyric acid transaminase, gamma-aminobutyric transaminase, 4-aminobutyrate aminotransferase, 4-aminobutyric acid aminotransferase, aminobutyrate transaminase, GABA aminotransferase, GABA transaminase, GABA transferase, POP2 (gene)) is an enzyme with systematic name 4-aminobutanoate:pyruvate aminotransferase.
[1][2][3][4] This enzyme is a type of GABA transaminase, which degrades the neurotransmitter GABA.
The enzyme catalyses the following chemical reaction This enzyme requires pyridoxal 5'-phosphate.
Phenylethylidenehydrazine, the active metabolite of phenelzine, inhibits gamma-aminobutyric acid transaminase and subsequently increases GABA concentrations in the central nervous system.
This may contribute to the notable anxiolytic effects of phenelzine.