4-aminobutyrate aminotransferase, bacterial <p>Eukaryotic 4-aminobutyrate aminotransferase (<db_xref db="EC" dbkey="2.6.1.19"/>) is a class III pyridoxal-phosphate-dependent aminotransferase. The enzyme catalyses the conversion of 4-aminobutanoate and 2-oxoglutarate into succinate semialdehyde and L-glutamate. The degree of sequence difference between this set and known bacterial examples is greater than the distance between, in either set, the most similar enzyme with a distinct function, and so the prokaryotic and eukaryotic sets have been placed into separate families. </p><p>This family describes known bacterial examples of the enzyme. The best archaeal matches arepresumed but not trusted to have the equivalent function. <taxon tax_id="562">Escherichia coli</taxon> has two isozymes. Alternate names include GABA transaminase, gamma-amino-N-butyrate transaminase, and beta-alanine--oxoglutarate aminotransferase.</p>