4-aminobutyrate aminotransferase, mitochondrial; gamma-amino-N-butyrate transaminase; GABA transaminase; GABA-T; GABA aminotransferase; GABA-AT; L-AIBAT; (S)-3-amino-2-methylpropionate transaminase (ABAT, GABAT)

Function

• catalyzes conversion of:
  • gamma-aminobutyrate to succinate semialdehyde &
  • L-beta-aminoisobutyrate to methylmalonatesemialdehyde
• can also convert delta-aminovalerate & beta-alanine

4-aminobutanoate + 2-oxoglutarate
           <-->
succinate semialdehyde + L-glutamate

(S)-3-amino-2-methylpropanoate + 2-oxoglutarate
           <-->
2-methyl-3-oxopropanoate + L-glutamate

Cofactor: pyridoxal phosphate

Structure

• homodimer (putative)
• belongs to the class-III pyridoxal-phosphate-dependent aminotransferase family

Compartment

mitochondrial matrix

Expression

• liver > pancreas > brain > kidney > heart > placenta

Pathology

• defects in ABAT are a cause of GABA-AT deficiency

More general terms

• aminotransferase
• mitochondrial protein

Database

• UniProt: http://www.uniprot.org/uniprot/P80404.html
• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=18
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:18
• OMIM: https://mirror.omim.org/entry/137150