2-aminoethylphosphonate--pyruvate transaminase (IPR012703)

Short name: NH2EtPonate_pyrv_transaminase

Overlapping homologous superfamilies

Family relationships


Phosphonates are a class of organophosphorus compounds, characterised by a stable C-P bond, which are found in a variety of biologically produced molecules including antiobiotics, lipids, proteins and polysaccharides [PMID: 11952414]. The functions of these molecules include phosphorus storage, cell communication, host recognition and chemical warfare. 2-Aminoethylphosphonate (AEP), the most common naturally occurring phosphonate, is an important precursor used in the biosynthesis of phosphonolipids, phosphonoproteins, and phosphonoglycans.

This entry represents 2-aminoethylphosphonate-pyruvate transaminase (AEPT) (EC: which catalyses the interconversion of AEP and phosphonoacetaldehyde (P-Ald), coupled with the interconversion of pryuvate and L-alanine. In some bacterial species this is the first step in an AEP degradation pathway which allows them to utilise this compound as a source of carbon, nitrogen and phosphorus. Phosphonoacetaldeyhde hydrolase, often encoded by an adjacent gene, then converts P-Ald to acetaldehyde and phosphate. Species with this pathway generally have an identified phosphonate ABC transporter but do not also have the multisubunit C-P lyase complex as found in Escherichia coli.

The crystal structure of AEPT from Salmonella typhimurium has been studied to 2.2 A resolution [PMID: 12403617]. The protein is a homodimer where each subunit is composed of two domains, large and small. The large domain forms an alpha-beta complex characteristic of the aspartate transaminase family, while the small domain is composed of highly twisted beta strands. The active site contains a pyridoxal 5'-phosphate cofactor and is found at the domain interface, being composed of residues from both subunits.

GO terms

Biological Process

GO:0019700 organic phosphonate catabolic process

Molecular Function

GO:0047304 2-aminoethylphosphonate-pyruvate transaminase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

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