Literature summary for 2.6.1.19 extracted from

Hong, J.; Kim, K.J.
Crystal structure of gamma-aminobutyrate aminotransferase in complex with a PLP-GABA adduct from Corynebacterium glutamicum (2019), Biochem. Biophys. Res. Commun., 514, 601-606 .

Cloned(Commentary)

Cloned (Comment)	Organism
gene Cgl0479, DNA and amino acid sequence comparisons, recombinant expression of His6-tagged enzyme in Escherichia coli strain BL21(DE3)-T1R	Corynebacterium glutamicum

Crystallization (Commentary)

Crystallization (Comment)	Organism
purified enzyme in complex with GABA and PLP, sitting drop vapor diffusion method, mixing of 0.001 ml of 42 mg/ml protein in 40 mM Tris-HCl, pH 8.0, and 300 mM sodium chloride, with 0.001 ml of reservoir solution containing 25% w/v PEG 3350, 0.1 M Bis-Tris, pH 6.5, and 0.2 M sodium chloride, and equilibration against 0.05 ml of reservoir solution method optimization, 20°C, X-ray diffraction structure determination and analysis at 1.90 A resolution, molecular replacement using the structure of GABA-AT from Paenarthrobacter aurescens TC1 (PDB ID 4ATP) as a search model	Corynebacterium glutamicum

Crystallization (Comment)

Organism

purified enzyme in complex with GABA and PLP, sitting drop vapor diffusion method, mixing of 0.001 ml of 42 mg/ml protein in 40 mM Tris-HCl, pH 8.0, and 300 mM sodium chloride, with 0.001 ml of reservoir solution containing 25% w/v PEG 3350, 0.1 M Bis-Tris, pH 6.5, and 0.2 M sodium chloride, and equilibration against 0.05 ml of reservoir solution method optimization, 20°C, X-ray diffraction structure determination and analysis at 1.90 A resolution, molecular replacement using the structure of GABA-AT from Paenarthrobacter aurescens TC1 (PDB ID 4ATP) as a search model

Corynebacterium glutamicum

Natural Substrates/ Products (Substrates)

Natural Substrates	Organism	Comment (Nat. Sub.)	Natural Products	Comment (Nat. Pro.)	Rev.
4-aminobutanoate + 2-oxoglutarate	Corynebacterium glutamicum	-	succinate semialdehyde + L-glutamate	-	r
4-aminobutanoate + 2-oxoglutarate	Corynebacterium glutamicum LMG 3730	-	succinate semialdehyde + L-glutamate	-	r
4-aminobutanoate + 2-oxoglutarate	Corynebacterium glutamicum BCRC 11384	-	succinate semialdehyde + L-glutamate	-	r
4-aminobutanoate + 2-oxoglutarate	Corynebacterium glutamicum ATCC 13032	-	succinate semialdehyde + L-glutamate	-	r
4-aminobutanoate + 2-oxoglutarate	Corynebacterium glutamicum JCM 1318	-	succinate semialdehyde + L-glutamate	-	r
4-aminobutanoate + 2-oxoglutarate	Corynebacterium glutamicum NCIMB 10025	-	succinate semialdehyde + L-glutamate	-	r
4-aminobutanoate + 2-oxoglutarate	Corynebacterium glutamicum DSM 20300	-	succinate semialdehyde + L-glutamate	-	r

Organism

Organism	UniProt	Comment	Textmining
Corynebacterium glutamicum	Q8NT35	-	-
Corynebacterium glutamicum ATCC 13032	Q8NT35	-	-
Corynebacterium glutamicum BCRC 11384	Q8NT35	-	-
Corynebacterium glutamicum DSM 20300	Q8NT35	-	-
Corynebacterium glutamicum JCM 1318	Q8NT35	-	-
Corynebacterium glutamicum LMG 3730	Q8NT35	-	-
Corynebacterium glutamicum NCIMB 10025	Q8NT35	-	-

Purification (Commentary)

Purification (Comment)	Organism
recombinant His6-tagged enzyme from Escherichia coli strain BL21(DE3)-T1R by nickel affinity chromatography and gel filtration	Corynebacterium glutamicum

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.
4-aminobutanoate + 2-oxoglutarate	-	Corynebacterium glutamicum	succinate semialdehyde + L-glutamate	-	r
4-aminobutanoate + 2-oxoglutarate	-	Corynebacterium glutamicum LMG 3730	succinate semialdehyde + L-glutamate	-	r
4-aminobutanoate + 2-oxoglutarate	-	Corynebacterium glutamicum BCRC 11384	succinate semialdehyde + L-glutamate	-	r
4-aminobutanoate + 2-oxoglutarate	-	Corynebacterium glutamicum ATCC 13032	succinate semialdehyde + L-glutamate	-	r
4-aminobutanoate + 2-oxoglutarate	-	Corynebacterium glutamicum JCM 1318	succinate semialdehyde + L-glutamate	-	r
4-aminobutanoate + 2-oxoglutarate	-	Corynebacterium glutamicum NCIMB 10025	succinate semialdehyde + L-glutamate	-	r
4-aminobutanoate + 2-oxoglutarate	-	Corynebacterium glutamicum DSM 20300	succinate semialdehyde + L-glutamate	-	r

Synonyms

Synonyms	Comment	Organism
CgGABA-AT	-	Corynebacterium glutamicum
GABA aminotransferase	-	Corynebacterium glutamicum
GABA-AT	-	Corynebacterium glutamicum
gamma-aminobutyrate aminotransferase	-	Corynebacterium glutamicum

Temperature Optimum [°C]

Temperature Optimum [°C]	Temperature Optimum Maximum [°C]	Comment	Organism
25	-	assay at	Corynebacterium glutamicum

pH Optimum

pH Optimum Minimum	pH Optimum Maximum	Comment	Organism
8	-	assay at	Corynebacterium glutamicum

Cofactor

Cofactor	Comment	Organism	Structure
pyridoxal 5'-phosphate	PLP, the PLP-GABA-binding pocket is located at the interface of the dimer formation and is composed of one alpha-helix (alpha4) with four loops (beta5-alpha5, beta7-alpha9, beta8-alpha10, and alpha12-alpha13). The positively charged pyridine nitrogen of PLP makes a salt bridge with the carboxylate group of Asp259. The hydroxyl group of the pyridine ring is hydrogen bonded with Gln262 and Lys288. Moreover, the pyridine ring is stabilized by being sandwiched between Tyr157 and Ile261, contributing to generation of van der Waals interactions. The phosphate group of PLP is stabilized by hydrogen bonds with the main chain nitrogen atoms of Gly130 and Ala131. The main chain of Thr317 from the neighboring monomer is also involved in hydrogen bonding with the phosphate group. The carboxylate group of GABA interacts with the N-terminus and the NE atom of Arg160, and Ile69 and Tyr157 form a substrate binding pocket. Ligand binding and binding site structure, overview	Corynebacterium glutamicum

General Information

General Information	Comment	Organism
evolution	transaminases structure comparisons, overview	Corynebacterium glutamicum
metabolism	the enzyme takes part in the GABA shunt pathway and GABA uptake/assimilation pathway in Corynebacterium glutamicum	Corynebacterium glutamicum
additional information	active site structure analysis, the epsilon-amino group of Lys288, the catalytic residue of CgGABA-AT, may form an internal aldimine with the aldehydic carbon of PLP, which is required for catalysis	Corynebacterium glutamicum