4-aminobutyrate transaminase

4-aminobutyrate transaminase
File:1ohv.jpg
Identifiers
EC number	2.6.1.19
CAS number	9037-67-6
Databases
IntEnz	IntEnz view
BRENDA	BRENDA entry
ExPASy	NiceZyme view
KEGG	KEGG entry
MetaCyc	metabolic pathway
PRIAM	profile
PDB structures	RCSB PDB PDBe PDBsum
Gene Ontology	AmiGO / QuickGO
Search PMC articles PubMed articles NCBI proteins

4-aminobutyrate transaminase
Identifiers
Symbol	ABAT
Entrez	18
HUGO	23
OMIM	137150
RefSeq	NM_020686
UniProt	P80404
Other data
Locus	Chr. 16 p13.2

In enzymology, 4-aminobutyrate transaminase (EC 2.6.1.19), also called GABA transaminase or 4-aminobutyrate aminotransferase, is an enzyme that catalyzes the chemical reaction:

4-aminobutanoate + 2-oxoglutarate <math>\rightleftharpoons</math> 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 belongs to the family of transferases, specifically the transaminases, which transfer nitrogenous groups. The systematic name of this enzyme class is 4-aminobutanoate:2-oxoglutarate aminotransferase. This enzyme participates in 5 metabolic pathways: alanine and aspartate metabolism, glutamate metabolism, beta-alanine metabolism, propanoate metabolism, and butanoate metabolism. It employs one cofactor, pyridoxal phosphate.

Structural Studies

As of late 2007, 9 structures have been solved for this class of enzymes, with PDB accession codes 1OHV, 1OHW, 1OHY, 1SF2, 1SFF, 1SZK, 1SZS, 1SZU, and 2EO5.

Inhibitors

Main article: GABA transaminase inhibitor

• Aminooxyacetic acid
• Gabaculine
• Phenelzine
• Phenylethylidenehydrazine (PEH)
• Rosmarinic acid
• Valproic acid
• Vigabatrin

Further reading

• Scott EM, Jakoby WB (April 1959). "Soluble gamma-aminobutyric-glutamic transaminase from Pseudomonas fluorescens". The Journal of Biological Chemistry. 234 (4): 932–6. PMID 13654294.
• Aurich H (October 1961). "[On the beta-alanine-alpha-ketoglutarate transaminase from Neurospora crassa]" [On the beta-alanine-alpha-ketoglutarate transaminase from Neurospora crassa]. Hoppe-Seyler's Zeitschrift für Physiologische Chemie (in Deutsch). 326: 25–33. doi:10.1515/bchm2.1961.326.1.25. PMID 13863304.
• Schousboe A, Wu JY, Roberts E (July 1973). "Purification and characterization of the 4-aminobutyrate--2,ketoglutarate transaminase from mouse brain". Biochemistry. 12 (15): 2868–73. doi:10.1021/bi00739a015. PMID 4719123.
• Parviz M, Vogel K, Gibson KM, Pearl PL (November 2014). "Disorders of GABA metabolism: SSADH and GABA-transaminase deficiencies" (PDF). Journal of Pediatric Epilepsy. 3 (4): 217–227. doi:10.3233/PEP-14097. PMC 4256671. PMID 25485164.

External links

• 4-Aminobutyrate+Transaminase at the US National Library of Medicine Medical Subject Headings (MeSH)
• Pearl, Phillip L., Parviz, Mahsa, Hodgeman, Ryan, Gibson, K. Michael. GABA-transaminase deficiency. In: Reimschisel T (ed.) MedLink Neurology. San Diego, California: MedLink Corporation. http://medlink.com/article/gaba-transaminase_deficiency