Branched-chain amino acid aminotransferase II (IPR005786)

Short name: B_amino_transII

Overlapping homologous superfamilies

Family relationships


Aminotransferases share certain mechanistic features with other pyridoxal-phosphate dependent enzymes, such as the covalent binding of the pyridoxal-phosphate group to a lysine residue. On the basis of sequence similarity, these various enzymes can be grouped [PMID: 1644759] into subfamilies.

One of these, called class-IV, currently consists of proteins of about 270 to 415 amino-acid residues that share a few regions of sequence similarity. Surprisingly, the best conserved region does not include the lysine residue to which the pyridoxal-phosphate group is known to be attached, in ilvE, but is located some 40 residues at the C terminus side of the PlP-lysine.

Among the class IV aminotransferases are two phylogenetically separable groups of branched-chain amino acid aminotransferase (IlvE) (EC: The last common ancestor of the two lineages appears also to have given rise to a family of D-amino acid aminotransferases (DAAT). This model represents the IlvE family less similar to the DAAT family.

Also included in this group is branched-chain amino acid aminotransferase gloG from the yeast Glarea lozoyensis, which is required for biosynthesis of the mycotoxin pneumocandin, a lipohexapeptide of the echinocandin family [PMID: 27705900]. Transaminase AMT5 from the Alternaria rot fungus is one of many enzymes required for the non-ribosomal biosynthesis of the cyclic depsipeptides known as AM-toxins [PMID: 17990954].

GO terms

Biological Process

GO:0009081 branched-chain amino acid metabolic process

Molecular Function

GO:0004084 branched-chain-amino-acid transaminase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.