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321  structures 1379  species 0  interactions 2142  sequences 16  architectures

Family: PTE (PF02126)

Summary: Phosphotriesterase family

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This is the Wikipedia entry entitled "Aryldialkylphosphatase". More...

Aryldialkylphosphatase Edit Wikipedia article

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Phosphotriesterase family Provide feedback

No Pfam abstract.

Internal database links

External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR001559

Bacteria such as Brevundimonas diminuta (Pseudomonas diminuta) harbour a plasmid that carries the gene for phosphotriesterase (PTE also known as parathion hydrolase; EC ). This enzyme has attracted interest because of its potential use in the detoxification of chemical waste and organophosphate warfare agents such as VX, soman, and sarin, 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 utilising paraoxon.

PTE exists as a homodimer with one active site per monomer. The active site is located next to a binuclear metal centre, at the C-terminal end of a TIM alpha- beta barrel motif. The native enzyme contains two zinc ions at the active site however these can be replaced with other metals such as cobalt, cadmium, nickel or manganese and the enzyme remains active [ PUBMED:10858282 , PUBMED:8396425 , PUBMED:9314115 , PUBMED:11170459 , PUBMED:7867909 ].

PTE belongs to a family [ PUBMED:9383406 , PUBMED: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:

  • Sulfolobus solfataricus aryldialkylphosphatase that has a low paraoxonase activity [ PUBMED:15909078 ].
  • E. coli php (phosphotriesterase homology) protein. The substrate of php is not yet known [ PUBMED:9548740 ].
  • Mycobacterium tuberculosis phosphotriesterase homology protein Rv0230C.
  • Phospho-furanose lactonase from Mycoplasma [ PUBMED:24955762 ].
  • Animal phosphotriesterase related protein (PTER) (RPR-1).

Gene Ontology

The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.

Domain organisation

Below is a listing of the unique domain organisations or architectures in which this domain is found. More...

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Pfam Clan

This family is a member of clan Amidohydrolase (CL0034), which has the following description:

This family includes a large family of metal dependent amidohydrolase enzymes [1].

The clan contains the following 17 members:

A_deaminase Amidohydro_1 Amidohydro_2 Amidohydro_3 AMP_deaminase CpsB_CapC DHOase DUF3604 DUF6282 Peptidase_M19 PHP PHP_C PTE RNase_P_p30 TatD_DNase Urease_alpha UxaC


We store a range of different sequence alignments for families. As well as the seed alignment from which the family is built, we provide the full alignment, generated by searching the sequence database (reference proteomes) using the family HMM. We also generate alignments using four representative proteomes (RP) sets and the UniProtKB sequence database. More...

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We make a range of alignments for each Pfam-A family. You can see a description of each above. You can view these alignments in various ways but please note that some types of alignment are never generated while others may not be available for all families, most commonly because the alignments are too large to handle.

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Representative proteomes UniProt

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You can also download a FASTA format file containing the full-length sequences for all sequences in the full alignment.

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HMM logos is one way of visualising profile HMMs. Logos provide a quick overview of the properties of an HMM in a graphical form. You can see a more detailed description of HMM logos and find out how you can interpret them here. More...


This page displays the phylogenetic tree for this family's seed alignment. We use FastTree to calculate neighbour join trees with a local bootstrap based on 100 resamples (shown next to the tree nodes). FastTree calculates approximately-maximum-likelihood phylogenetic trees from our seed alignment.

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Curation and family details

This section shows the detailed information about the Pfam family. You can see the definitions of many of the terms in this section in the glossary and a fuller explanation of the scoring system that we use in the scores section of the help pages.

Curation View help on the curation process

Seed source: IPR001559
Previous IDs: none
Type: Domain
Sequence Ontology: SO:0000417
Author: Mian N , Bateman A , Griffiths-Jones SR
Number in seed: 3
Number in full: 2142
Average length of the domain: 294.40 aa
Average identity of full alignment: 28 %
Average coverage of the sequence by the domain: 92.57 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 57096847 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 22.4 22.4
Trusted cut-off 22.4 22.4
Noise cut-off 22.3 22.3
Model length: 298
Family (HMM) version: 20
Download: download the raw HMM for this family

Species distribution

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Colour assignments

Archea Archea Eukaryota Eukaryota
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Viruses Viruses Unclassified Unclassified
Viroids Viroids Unclassified sequence Unclassified sequence


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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the PTE domain has been found. There are 321 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein sequence.

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