Gene and Protein Information
Species	TM	AA	Chromosomal Location	Gene Symbol	Gene Name	Reference
Human	-	392	19q13.33	BCAT2	branched chain amino acid transaminase 2	1
Mouse	-	393	7 29.36 cM	Bcat2	branched chain aminotransferase 2, mitochondrial
Rat	-	393	1q22	Bcat2	branched chain amino acid transaminase 2	1
Gene and Protein Information Comments
For the human gene and protein we provide details for the longest form, isoform a (from transcript variant a) also known as PP18a. Isoforms b and c (PP18b, PP18c) are shorter at 300 and 352 amino acids (aa) respectively. Two mouse isoforms are produced from 3 transcript variants. Isoform 1 is the longest (details in the table), with isoform 2 having a shorter N-terminus (353 aa).

Previous and Unofficial Names

BCATm | BCAM | BCT2 | Eca40 (Mm) | Bcat-2 | mBcat | branched-chain-amino-acid aminotransferase, mitochondrial | branched chain aminotransferase 2, mitochondrial | branched chain aminotransferase 2

Database Links
Alphafold	O15382 (Hs), O35855 (Mm), O35854 (Rn)
BRENDA	2.6.1.42
ChEMBL Target	CHEMBL3616354 (Hs), CHEMBL3319 (Rn)
Ensembl Gene	ENSG00000105552 (Hs), ENSMUSG00000030826 (Mm), ENSRNOG00000020956 (Rn)
Entrez Gene	587 (Hs), 12036 (Mm), 64203 (Rn)
Human Protein Atlas	ENSG00000105552 (Hs)
KEGG Enzyme	2.6.1.42
KEGG Gene	hsa:587 (Hs), mmu:12036 (Mm), rno:64203 (Rn)
OMIM	113530 (Hs)
Pharos	O15382 (Hs)
RefSeq Nucleotide	NM_001190 (Hs), NM_001164773 (Hs), NM_001284325 (Hs), NM_001243052 (Mm), NM_001243053 (Mm), NM_009737 (Mm), NM_022400 (Rn)
RefSeq Protein	NP_001158245 (Hs), NP_001181 (Hs), NP_001271254 (Hs), NP_001229982 (Mm), NP_033867 (Mm), NP_001229981 (Mm), NP_071795 (Rn)
UniProtKB	O15382 (Hs), O35855 (Mm), O35854 (Rn)
Wikipedia	BCAT2 (Hs)

Selected 3D Structures
	Description:  X-ray crystal structure at 1.65A resolution of human mitochondrial branched chain aminotransferase (BCATm) complexed with a thiazole compound and pmp cofactor. PDB Id:  5I5X Ligand:  compound 27 [PMID: 26938474] Resolution:  1.65Å Species:  Human References:  2

Enzyme Reaction
EC Number: 2.6.1.42 Description Reaction Reference L-leucine + 2-oxoglutarate <=> 4-methyl-2-oxopentanoate + L-glutamate L-isoleucine + 2-oxoglutarate <=> (S)-3-methyl-2-oxopentanoate + L-glutamate L-valine + 2-oxoglutarate <=> 3-methyl-2-oxobutanoate + L-glutamate

Download all structure-activity data for this target as a CSV file

Inhibitors
Key to terms and symbols	View all chemical structures	Click column headers to sort
Ligand Sp. Action Value Parameter Reference BAY-069 Hs Inhibition 6.8 pIC50 3 ⤷ pIC50 6.8 (IC50 1.53x10-7 M) [3] compound 27 [PMID: 26938474] Hs Inhibition 6.7 pIC50 2 ⤷ pIC50 6.7 (IC50 1.99x10-7 M) [2] compound 42 [PMID: 26938474] Hs Inhibition 5.8 pIC50 2 ⤷ pIC50 5.8 (IC50 1.585x10-6 M) [2]

Immuno Process Associations

Immuno Process:  Cytokine production & signalling

Tissue Distribution Comments

In mammals, BCAT2 (BCATm) is expressed in most tissues [4]. In comparison, expression of the cytosilic isozyme BCAT1 (BCATc; UniProt P54687) is restricted to the CNS.

Physiological Consequences of Altering Gene Expression
Bcat2 knockout mice are resistant to high-fat diet induced obesity and diabetes Species:  Mouse Tissue:  Technique:  Gene knockout References:  5

General Comments

BCAT2 is a mitochondrial protein that catalyses the first step in the production of the branched chain amino acids leucine, isoleucine, and valine. HGNC places this protein in the minor histocompatibility antigen (MHA) family. MHAs are known to induce an immunological response in some organ transplants, albeit to a much lesser degree than the major histocompatibility complex (MHC) antigens. Amino acid differences in MHAs can cause slow rejection of transplanted organs even when MHCs are comprehensively matched between donor and recipient.