Gene: [19^/BCAT2] branched chain aminotransferase 2, mitochondrial; transaminase 2 of branched chain amino acids (BCAA); hyperleucine-isoleucinemia (BCAA transaminase 2 deficiency?);

COM

[1] The GDB erroneously indicates, for transaminases of branched chain amino acids (BCAA-1 isoform is encoded by gene GEM:12p1/BCAT1), the code EC:2.6.1.26, which corresponds to thyroid hormone aminotransferase.
[2] The Enzyme Nomenclature (EN-1984) registered three enzymes, which functions are similar with that of BCAA but subsstrate specificities are narrower: 2.6.1.6 - leucine aminotransferase, 2.6.1.32 - valine-3-methyl-2-oxovalerate aminotransferase (valine-isoleucine aminotransferase, 2.6.1.66 - valine-pyruvate aminotrasferase. Corresponding human genes are not described yet."

FUN

Systematic name: branched-chain-amino-acid:2-oxoglutarate aminotransferase. The catalyzed reaction: L-leucine + 2-oxoglutarate = 4-methyl-2-oxopentanoate + L-glutamate. Also acts on L-isoleucine and L-valine."

PAT

[1] A familial type of hyperleucine-isoleucinemia with accumulation of isoleucine, leucine, and proline in tissues is described (Jeune-1970; MIM:238340). This pathology is assumed to be related with at least two independent genetic defects: BCAA-2 (or BCAA-1) deficiency and altered proline degradation. We registered BCAA-2 deficiency by presumption (see GEM:12p1/BCAT1).
[2] Hypervalinemia is described in more detail (MIM:277100; Wada-1963, Dancis-1967, Nada-1967). It is considered to be determined by an isolated defect of valine transamination. This type of hypervalinemia is possible to be related to the deficiency of valine aminotransferase, which is not presently identified in human, or to a mutation in the BCAA active center that prevents valine binding without decreasing the affinity to other branched chain amino acids (leucine and isoleucine)."

REF

CLO,SEQ "Bledsoe RK &: BBA, 1339, 9-13, 1997
REV,PAT,PHE,MEB,FOG "Dancis, Levitz: (in) MBID, 4th ed, pp.397-410, 1978
COM,PHE,PAT "Dancis &: Pediatrics, 39, 813-817, 1967
REV,PAT,PHE,MEB,FOG "Danner, Elsas: (in) MBID, 6th ed, pp.671-692, 1989
CLO,SEQ "Eden A &: JBC, 271, N34, 20242-20245, 1996
FUN,PEP "Goto &: Gann, 68, 663-667, 1977
PAT,PHE,MEB,FOG "Jeune &: Ann Pediatr, 17, 85-99, 1970
FAG "Jones C, Moore: Hum Genet, 66, 206-211, 1984
FAG "Jones C, Moore: CCG, 25, (HGM5), 168, 1979
LOC,CYG "Naylor SL, Shows: Somat Cell Genet, 6, N5, 641-652, 1980
LOC,CYG "Naylor SL, Shows: CCG, 25, (HGM5), 191-192, 1979
COM,PHE,PAT "Tada &: Am J Dis Child, 113, 64-67, 1967
COM,PHE,PAT "Wada &: Tohoku J Exp Med, 81, 46-55, 1963

SWI

SWISSPROT: O15382

KEY

aac, mtbd

CLA

coding, basic

LOC

19

MIM

MIM: 113530

EZN

ENZYME: 2.6.1.42