UniProtKB - P22256 (GABT_ECOLI)
Protein
4-aminobutyrate aminotransferase GabT
Gene
gabT
Organism
Escherichia coli (strain K12)
Status
Functioni
Pyridoxal phosphate-dependent enzyme that catalyzes transamination between primary amines and alpha-keto acids. Catalyzes the transfer of the amino group from gamma-aminobutyrate (GABA) to alpha-ketoglutarate (KG) to yield succinic semialdehyde (SSA) and glutamate (PubMed:15723541, PubMed:30498244). Thereby functions in a GABA degradation pathway that allows some E.coli strains to utilize GABA as a nitrogen source for growth (PubMed:12446648). Also catalyzes the conversion of 5-aminovalerate to glutarate semialdehyde, as part of a L-lysine degradation pathway that proceeds via cadaverine, glutarate and L-2-hydroxyglutarate (PubMed:30498244).3 Publications
Catalytic activityi
- EC:2.6.1.192 PublicationsThis reaction proceeds in the forward1 Publication direction.
- EC:2.6.1.481 PublicationThis reaction proceeds in the forward1 Publication direction.
Cofactori
pyridoxal 5'-phosphate2 Publications
Kineticsi
kcat is 47.4 sec(-1) with 4-aminobutanoate as substrate (at 25 degrees Celsius and pH 7.8).1 Publication
- KM=197 µM for 4-aminobutanoate (measured for a coupled GabT/GabD reaction)1 Publication
- KM=439 µM for 5-aminopentanoate (measured for a coupled GabT/GabD reaction)1 Publication
- KM=5.8 mM for 4-aminobutanoate (at 25 degrees Celsius and pH 7.8)1 Publication
- KM=1.07 mM for 2-oxoglutarate (at 25 degrees Celsius and pH 7.8)1 Publication
: 4-aminobutanoate degradation Pathwayi
This protein is involved in the pathway 4-aminobutanoate degradation, which is part of Amino-acid degradation.1 PublicationView all proteins of this organism that are known to be involved in the pathway 4-aminobutanoate degradation and in Amino-acid degradation.
Pathwayi: Amino-acid degradation
This protein is involved in Amino-acid degradation.1 PublicationView all proteins of this organism that are known to be involved in Amino-acid degradation.
Sites
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Binding sitei | 242 | Pyridoxal phosphate2 Publications | 1 | |
Binding sitei | 297 | Pyridoxal phosphate2 Publications | 1 |
GO - Molecular functioni
- 4-aminobutyrate:2-oxoglutarate transaminase activity Source: EcoCyc
- 4-aminobutyrate transaminase activity Source: EcoCyc
- 5-aminovalerate transaminase activity Source: EcoCyc
- N2-acetyl-L-ornithine:2-oxoglutarate 5-aminotransferase activity Source: EcoCyc
- pyridoxal phosphate binding Source: EcoCyc
GO - Biological processi
- arginine biosynthetic process via ornithine Source: EcoCyc
- gamma-aminobutyric acid catabolic process Source: EcoCyc
Keywordsi
Molecular function | Aminotransferase, Transferase |
Ligand | Pyridoxal phosphate |
Enzyme and pathway databases
BioCyci | EcoCyc:GABATRANSAM-MONOMER MetaCyc:GABATRANSAM-MONOMER |
BRENDAi | 2.6.1.19, 2026 |
SABIO-RKi | P22256 |
UniPathwayi | UPA00733 |
Names & Taxonomyi
Protein namesi | Recommended name: 4-aminobutyrate aminotransferase GabT (EC:2.6.1.192 Publications)Alternative name(s): 5-aminovalerate transaminase1 Publication (EC:2.6.1.481 Publication) GABA aminotransferase Short name: GABA-AT Gamma-amino-N-butyrate transaminase Short name: GABA transaminase Glutamate:succinic semialdehyde transaminase L-AIBAT |
Gene namesi | Name:gabT Ordered Locus Names:b2662, JW2637 |
Organismi | Escherichia coli (strain K12) |
Taxonomic identifieri | 83333 [NCBI] |
Taxonomic lineagei | Bacteria › Proteobacteria › Gammaproteobacteria › Enterobacterales › Enterobacteriaceae › Escherichia › |
Proteomesi |
|
Pathology & Biotechi
Disruption phenotypei
Cells lacking this gene are not able to utilize GABA as a nitrogen source, in contrast to wild-type, but grow normally with arginine, ornithine, putrescine and agmatine (PubMed:12446648). Cells show only 68% of the wild-type GABA aminotransferase activity (PubMed:20639325).2 Publications
Mutagenesis
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Mutagenesisi | 50 | I → Q: 3-fold decrease in catalytic activity and 12-fold decrease in affinity for GABA. 1 Publication | 1 | |
Mutagenesisi | 211 | E → S: 100-fold decrease in catalytic activity and 15-fold decrease in affinity for GABA. 1 Publication | 1 | |
Mutagenesisi | 241 | V → A: 25-fold decrease in catalytic activity and 5-fold decrease in affinity for GABA. 1 Publication | 1 |
Chemistry databases
DrugBanki | DB02783, 4'-Deoxy-4'-Acetylyamino-Pyridoxal-5'-Phosphate DB02142, Pyridoxamine-5'-Phosphate |
PTM / Processingi
Molecule processing
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
ChainiPRO_0000120384 | 1 – 426 | 4-aminobutyrate aminotransferase GabTAdd BLAST | 426 |
Amino acid modifications
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Modified residuei | 268 | N6-(pyridoxal phosphate)lysineCombined sources2 Publications | 1 |
Proteomic databases
jPOSTi | P22256 |
PaxDbi | P22256 |
PRIDEi | P22256 |
Expressioni
Inductioni
Induced by RpoS in response to multiple stress conditions, including shifts to acidic pH or high osmolarity as well as starvation or stationary phase. Catabolite repression by glucose (repression relieved by GABA) (PubMed:14731280). Makes part of the gabDTPC operon, which is up-regulated by nitrogen limitation (PubMed:12446648).2 Publications
Interactioni
Subunit structurei
Homotetramer.
2 PublicationsProtein-protein interaction databases
BioGRIDi | 4259210, 22 interactors 852375, 2 interactors |
DIPi | DIP-9725N |
IntActi | P22256, 12 interactors |
STRINGi | 511145.b2662 |
Structurei
Secondary structure
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details3D structure databases
SMRi | P22256 |
ModBasei | Search... |
PDBe-KBi | Search... |
Miscellaneous databases
EvolutionaryTracei | P22256 |
Family & Domainsi
Region
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Regioni | 111 – 112 | Pyridoxal phosphate binding2 Publications | 2 |
Sequence similaritiesi
Belongs to the class-III pyridoxal-phosphate-dependent aminotransferase family.Curated
Phylogenomic databases
eggNOGi | COG0160, Bacteria |
HOGENOMi | CLU_016922_10_0_6 |
InParanoidi | P22256 |
PhylomeDBi | P22256 |
Family and domain databases
CDDi | cd00610, OAT_like, 1 hit |
Gene3Di | 3.40.640.10, 1 hit 3.90.1150.10, 1 hit |
InterProi | View protein in InterPro IPR004632, 4NH2But_aminotransferase_bac IPR005814, Aminotrans_3 IPR015424, PyrdxlP-dep_Trfase IPR015422, PyrdxlP-dep_Trfase_dom1 IPR015421, PyrdxlP-dep_Trfase_major |
Pfami | View protein in Pfam PF00202, Aminotran_3, 1 hit |
PIRSFi | PIRSF000521, Transaminase_4ab_Lys_Orn, 1 hit |
SUPFAMi | SSF53383, SSF53383, 1 hit |
TIGRFAMsi | TIGR00700, GABAtrnsam, 1 hit |
PROSITEi | View protein in PROSITE PS00600, AA_TRANSFER_CLASS_3, 1 hit |
i Sequence
Sequence statusi: Complete.
P22256-1 [UniParc]FASTAAdd to basket
10 20 30 40 50
MNSNKELMQR RSQAIPRGVG QIHPIFADRA ENCRVWDVEG REYLDFAGGI
60 70 80 90 100
AVLNTGHLHP KVVAAVEAQL KKLSHTCFQV LAYEPYLELC EIMNQKVPGD
110 120 130 140 150
FAKKTLLVTT GSEAVENAVK IARAATKRSG TIAFSGAYHG RTHYTLALTG
160 170 180 190 200
KVNPYSAGMG LMPGHVYRAL YPCPLHGISE DDAIASIHRI FKNDAAPEDI
210 220 230 240 250
AAIVIEPVQG EGGFYASSPA FMQRLRALCD EHGIMLIADE VQSGAGRTGT
260 270 280 290 300
LFAMEQMGVA PDLTTFAKSI AGGFPLAGVT GRAEVMDAVA PGGLGGTYAG
310 320 330 340 350
NPIACVAALE VLKVFEQENL LQKANDLGQK LKDGLLAIAE KHPEIGDVRG
360 370 380 390 400
LGAMIAIELF EDGDHNKPDA KLTAEIVARA RDKGLILLSC GPYYNVLRIL
410 420
VPLTIEDAQI RQGLEIISQC FDEAKQ
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | M88334 Genomic DNA Translation: AAC36832.1 U00096 Genomic DNA Translation: AAC75709.1 AP009048 Genomic DNA Translation: BAA16525.1 |
PIRi | A37846 |
RefSeqi | NP_417148.1, NC_000913.3 WP_001087611.1, NZ_LN832404.1 |
Genome annotation databases
EnsemblBacteriai | AAC75709; AAC75709; b2662 BAA16525; BAA16525; BAA16525 |
GeneIDi | 57728679 948067 |
KEGGi | ecj:JW2637 eco:b2662 |
PATRICi | fig|1411691.4.peg.4079 |
Similar proteinsi
Cross-referencesi
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | M88334 Genomic DNA Translation: AAC36832.1 U00096 Genomic DNA Translation: AAC75709.1 AP009048 Genomic DNA Translation: BAA16525.1 |
PIRi | A37846 |
RefSeqi | NP_417148.1, NC_000913.3 WP_001087611.1, NZ_LN832404.1 |
3D structure databases
Select the link destinations: PDBei RCSB PDBi PDBji Links Updated | PDB entry | Method | Resolution (Å) | Chain | Positions | PDBsum |
1SF2 | X-ray | 2.40 | A/B/C/D | 1-426 | [»] | |
1SFF | X-ray | 1.90 | A/B/C/D | 1-426 | [»] | |
1SZK | X-ray | 2.52 | A/B/C/D | 1-426 | [»] | |
1SZS | X-ray | 2.10 | A/B/C/D | 1-426 | [»] | |
1SZU | X-ray | 2.52 | A/B/C/D | 1-426 | [»] | |
SMRi | P22256 | |||||
ModBasei | Search... | |||||
PDBe-KBi | Search... |
Protein-protein interaction databases
BioGRIDi | 4259210, 22 interactors 852375, 2 interactors |
DIPi | DIP-9725N |
IntActi | P22256, 12 interactors |
STRINGi | 511145.b2662 |
Chemistry databases
DrugBanki | DB02783, 4'-Deoxy-4'-Acetylyamino-Pyridoxal-5'-Phosphate DB02142, Pyridoxamine-5'-Phosphate |
Proteomic databases
jPOSTi | P22256 |
PaxDbi | P22256 |
PRIDEi | P22256 |
Genome annotation databases
EnsemblBacteriai | AAC75709; AAC75709; b2662 BAA16525; BAA16525; BAA16525 |
GeneIDi | 57728679 948067 |
KEGGi | ecj:JW2637 eco:b2662 |
PATRICi | fig|1411691.4.peg.4079 |
Organism-specific databases
EchoBASEi | EB0356 |
Phylogenomic databases
eggNOGi | COG0160, Bacteria |
HOGENOMi | CLU_016922_10_0_6 |
InParanoidi | P22256 |
PhylomeDBi | P22256 |
Enzyme and pathway databases
UniPathwayi | UPA00733 |
BioCyci | EcoCyc:GABATRANSAM-MONOMER MetaCyc:GABATRANSAM-MONOMER |
BRENDAi | 2.6.1.19, 2026 |
SABIO-RKi | P22256 |
Miscellaneous databases
EvolutionaryTracei | P22256 |
PROi | PR:P22256 |
Family and domain databases
CDDi | cd00610, OAT_like, 1 hit |
Gene3Di | 3.40.640.10, 1 hit 3.90.1150.10, 1 hit |
InterProi | View protein in InterPro IPR004632, 4NH2But_aminotransferase_bac IPR005814, Aminotrans_3 IPR015424, PyrdxlP-dep_Trfase IPR015422, PyrdxlP-dep_Trfase_dom1 IPR015421, PyrdxlP-dep_Trfase_major |
Pfami | View protein in Pfam PF00202, Aminotran_3, 1 hit |
PIRSFi | PIRSF000521, Transaminase_4ab_Lys_Orn, 1 hit |
SUPFAMi | SSF53383, SSF53383, 1 hit |
TIGRFAMsi | TIGR00700, GABAtrnsam, 1 hit |
PROSITEi | View protein in PROSITE PS00600, AA_TRANSFER_CLASS_3, 1 hit |
ProtoNeti | Search... |
MobiDBi | Search... |
Entry informationi
Entry namei | GABT_ECOLI | |
Accessioni | P22256Primary (citable) accession number: P22256 | |
Entry historyi | Integrated into UniProtKB/Swiss-Prot: | August 1, 1991 |
Last sequence update: | August 1, 1991 | |
Last modified: | April 7, 2021 | |
This is version 177 of the entry and version 1 of the sequence. See complete history. | ||
Entry statusi | Reviewed (UniProtKB/Swiss-Prot) | |
Annotation program | Prokaryotic Protein Annotation Program |
Miscellaneousi
Keywords - Technical termi
3D-structure, Direct protein sequencing, Reference proteomeDocuments
- PATHWAY comments
Index of metabolic and biosynthesis pathways - PDB cross-references
Index of Protein Data Bank (PDB) cross-references - SIMILARITY comments
Index of protein domains and families