4-aminobutyrate—pyruvate transaminase

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

(1) 4-aminobutanoate + pyruvate ${\displaystyle \rightleftharpoons }$ succinate semialdehyde + L-alanine

(2) 4-aminobutanoate + glyoxylate ${\displaystyle \rightleftharpoons }$ succinate semialdehyde + glycine

4-aminobutyrate---pyruvate transaminase
Identifiers
EC no.	2.6.1.96
Databases
IntEnz	IntEnz view
BRENDA	BRENDA entry
ExPASy	NiceZyme view
KEGG	KEGG entry
MetaCyc	metabolic pathway
PRIAM	profile
PDB structures	RCSB PDB PDBe PDBsum
Search PMC articles PubMed articles NCBI proteins

This enzyme requires pyridoxal 5'-phosphate.

Clinical significance

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.^[5]