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4  structures 104  species 0  interactions 150  sequences 5  architectures

Family: Metallothio_PEC (PF02068)

Summary: Plant PEC family metallothionein

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Plant PEC family metallothionein Provide feedback

No Pfam abstract.

Internal database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR000316

Metallothioneins (MT) are small proteins that bind heavy metals, such as zinc, copper, cadmium, nickel, etc. They have a high content of cysteine residues that bind the metal ions through clusters of thiolate bonds [ PUBMED:1779825 , PUBMED:2959513 , PUBMED:3064814 , PUBMED:2959504 ]. An empirical classification into three classes has been proposed by Fowler and coworkers [ PUBMED:2959504 ] and Kojima [ PUBMED:1779826 ]. Members of class I are defined to include polypeptides related in the positions of their cysteines to equine MT-1B, and include mammalian MTs as well as MTs from crustaceans and molluscs. Class II groups MTs from a variety of species, including sea urchins, fungi, insects and cyanobacteria. Class III MTs are atypical polypeptides composed of gamma-glutamylcysteinyl units [ PUBMED:2959504 ]. This original classification system has been found to be limited, in the sense that it does not allow clear differentiation of patterns of structural similarities, either between or within classes. Consequently, all class I and class II MTs (the proteinaceous sequences) have now been grouped into families of phylogenetically-related and thus alignable sequences. This system subdivides the MT superfamily into families, subfamilies, subgroups, and isolated isoforms and alleles. The metallothionein superfamily comprises all polypeptides that resemble equine renal metallothionein in several respects [ PUBMED:2959504 ]: e.g., low molecular weight; high metal content; amino acid composition with high Cys and low aromatic residue content; unique sequence with characteristic distribution of cysteines, and spectroscopic manifestations indicative of metal thiolate clusters. A MT family subsumes MTs that share particular sequence-specific features and are thought to be evolutionarily related. The inclusion of a MT within a family presupposes that its amino acid sequence is alignable with that of all members. Fifteen MT families have been characterised, each family being identified by its number and its taxonomic range: e.g., Family 1: vertebrate MTs.

Family 15 consists of planta MTs. Its members are recognised by the sequence pattern [YFH]-x(5,25)-C-[SKD]-C-[GA]-[SDPAT]-x(0,1)-C-x-[CYF] which yields all plant sequences, but also MTCU_HELPO and the non-MT ITB3_HUMAN. The taxonomic range of the members extends to planta. Planta MTs are 45-84 residue proteins, containing 17 conserved cysteines that bind 5 zinc ions. Generally, there are two Cys-rich regions (domain 1 and domain 3) separated by a Cys-poor region (domain 2) and only the domain 2 contains unusual residues. It is believed that the proteins may have a role in Zn 2+ homeostasis during embryogenesis. Family 15 includes the following subfamilies: p1, p2, p2v, p3, pec, p21.

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 Metallothionein (CL0461), which has the following description:

This superfamily contains related families of metallothioneins, prokaryotes and eukaryotes.

The clan contains the following 7 members:

Metallothi_Euk2 Metallothio Metallothio_6 Metallothio_Euk Metallothio_PEC Metallothio_Pro Yeast_MT

Alignments

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.

  Seed
(8)
Full
(150)
Representative proteomes UniProt
(221)
RP15
(24)
RP35
(86)
RP55
(128)
RP75
(169)
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PP/heatmap 1 View           

1Cannot generate PP/Heatmap alignments for seeds; no PP data available

Key: ✓ available, x not generated, not available.

Format an alignment

  Seed
(8)
Full
(150)
Representative proteomes UniProt
(221)
RP15
(24)
RP35
(86)
RP55
(128)
RP75
(169)
Alignment:
Format:
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Sequence:
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We make all of our alignments available in Stockholm format. You can download them here as raw, plain text files or as gzip-compressed files.

  Seed
(8)
Full
(150)
Representative proteomes UniProt
(221)
RP15
(24)
RP35
(86)
RP55
(128)
RP75
(169)
Raw Stockholm Download   Download   Download   Download   Download   Download   Download  
Gzipped Download   Download   Download   Download   Download   Download   Download  

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

HMM logo

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...

Trees

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.

Note: You can also download the data file for the tree.

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: IPR000316
Previous IDs: none
Type: Family
Sequence Ontology: SO:0100021
Author: Mian N , Bateman A
Number in seed: 8
Number in full: 150
Average length of the domain: 73.7 aa
Average identity of full alignment: 51 %
Average coverage of the sequence by the domain: 80.27 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 61295632 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 31.8 31.8
Trusted cut-off 31.9 34.5
Noise cut-off 29.8 31.6
Model length: 75
Family (HMM) version: 19
Download: download the raw HMM for this family

Species distribution

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Archea Archea Eukaryota Eukaryota
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Viroids Viroids Unclassified sequence Unclassified sequence

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This visualisation provides a simple graphical representation of the distribution of this family across species. You can find the original interactive tree in the adjacent tab. More...

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Structures

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 Metallothio_PEC domain has been found. There are 4 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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AlphaFold Structure Predictions