Binding Site

Aryldialkylphosphatase, zinc-binding site (IPR017947)

Short name: AryldialkylPase_Zn-BS


Synonym(s): Paraoxonase, A-esterase, Aryltriphosphatase, Phosphotriesterase, Paraoxon hydrolase

Bacteria such as Brevundimonas diminuta (Pseudomonas diminuta) harbour a plasmid that carries the gene for aryldialkylphosphatase (EC: (PTE) (also known as parathion hydrolase). This enzyme has attracted interest because of its potential use in the detoxification of chemical waste and warfare agents and its ability to degrade agricultural pesticides such as parathion. It acts specifically on synthetic organophosphate triesters and phosphorofluoridates. It does not seem to have a naturally occuring substrate and may thus have optimally evolved for utilizing paraoxon.

Aryldialkylphosphatase belongs to a family [PMID: 9383406, PMID: 9548740] of enzymes that possess a binuclear zinc metal centre at their active site. The two zinc ions are coordinated by six different residues, six of which being histidines. This family so far includes, in addition to the parathion hydrolase, the following proteins:

  • Escherichia coli protein Php, the substrate of which is not yet known.
  • Mycobacterium tuberculosis phosphotriesterase homology protein Rv0230C.
  • Mammalian phosphotriesterase related protein (PTER) (RPR-1).

This entry corresponds to the region located in the N-terminal section that contains two histidines that bind the first of the two zinc ions.

GO terms

Biological Process

GO:0009056 catabolic process

Molecular Function

GO:0016788 hydrolase activity, acting on ester bonds
GO:0008270 zinc ion binding

Cellular Component

No terms assigned in this category.

Contributing signatures

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