Summary: ParD-like antitoxin of type II bacterial toxin-antitoxin system
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Toxin-antitoxin system Edit Wikipedia article
A toxin-antitoxin system is a set of two or more closely linked genes that together encode both a "toxin" protein and a corresponding "antitoxin". Toxin-antitoxin systems are widely distributed in prokaryotes, and organisms often have them in multiple copies. When these systems are contained on plasmids â€“ transferable genetic elements â€“ they ensure that only the daughter cells that inherit the plasmid survive after cell division. If the plasmid is absent in a daughter cell, the unstable antitoxin is degraded and the stable toxic protein kills the new cell; this is known as 'post-segregational killing' (PSK).
Toxin-antitoxin systems are typically classified according to how the antitoxin neutralises the toxin. In a type I toxin-antitoxin system, the translation of messenger RNA (mRNA) that encodes the toxin is inhibited by the binding of a small non-coding RNA antitoxin that binds the toxin mRNA. The toxic protein in a type II system is inhibited post-translationally by the binding of an antitoxin protein. Type III toxin-antitoxin systems consist of a small RNA that binds directly to the toxin protein and inhibits its activity. There are also types IV-VI, which are less common. Toxin-antitoxin genes are often inherited through horizontal gene transfer and are associated with pathogenic bacteria, having been found on plasmids conferring antibiotic resistance and virulence.
Chromosomal toxin-antitoxin systems also exist, some of which are thought to perform cell functions such as responding to stresses, causing cell cycle arrest and bringing about programmed cell death. In evolutionary terms, toxin-antitoxin systems can be considered selfish DNA in that the purpose of the systems are to replicate, regardless of whether they benefit the host organism or not. Some have proposed adaptive theories to explain the evolution of toxin-antitoxin systems; for example, chromosomal toxin-antitoxin systems could have evolved to prevent the inheritance of large deletions of the host genome. Toxin-antitoxin systems have several biotechnological applications, such as maintaining plasmids in cell lines, targets for antibiotics, and as positive selection vectors.
- 1 Biological functions
- 2 System types
- 3 Biotechnological applications
- 4 See also
- 5 References
- 6 External links
Stabilization and fitness of mobile DNA
As stated above, toxin-antitoxin systems are well characterized as plasmid addiction modules. It was also proposed that toxin-antitoxin systems have evolved as plasmid exclusion modules. A cell that would carry two plasmids from the same incompatibility group will eventually generate two daughters cells carrying either plasmid. Should one of these plasmids encode for a TA system, its "displacement" by another TA-free plasmid system will prevent its inheritance and thus induce post-segregetational killing. This theory was corroborated through computer modelling. Toxin-antitoxin systems can also be found on other mobile genetic elements such as conjugative transposons and temperate bacteriophages and could be implicated in the maintenance and competition of these elements.
Toxin-antitoxin systems could prevent harmful large deletions in a bacterial genome, though arguably deletions of large coding regions are fatal to a daughter cell regardless. In Vibrio cholerae, multiple type II toxin-antitoxin systems located in a super-integron were shown to prevent the loss of gene cassettes.
Altruistic cell death
mazEF, a toxin-antitoxin locus found in E. coli and other bacteria, was proposed to induce programmed cell death in response to starvation, specifically a lack of amino acids. This would release the cell's contents for absorption by neighbouring cells, potentially preventing the death of close relatives, and thereby increasing the inclusive fitness of the cell that perished. This would be an example of altruism and how bacterial colonies could resemble multicellular organisms. However, the "mazEF-mediated PCD" has largely been refuted by several studies.
Another theory states that chromosomal toxin-antitoxin systems are designed to be bacteriostatic rather than bactericidal. RelE, for example, is a global inhibitor of translation, is induced during nutrient stress. By shutting down translation under stress, it could reduce the chance of starvation by lowering the cell's nutrient requirements. However, it was shown that several toxin-antitoxin systems, including relBE, do not give any competitive advantage under any stress condition.
It has been proposed that chromosomal homologues of plasmid toxin-antitoxin systems may serve as anti-addiction modules, which would allow progeny to lose a plasmid without suffering the effects of the toxin it encodes. For example, a chromosomal copy of the ccdA antitoxin encoded in the chromosome of Erwinia chrysanthemi is able to neutralize the ccdB toxin encoded on the F plasmid and thus, prevent toxin activation when such a plasmid is lost. Similarly, the ataR antitoxin encoded on the chromosome of E. coli O157:H7 is able neutralize the ataTP toxin encoded on plasmids found in other enterohemorragic E. coli.
Type III toxin-antitoxin systems have been shown to protect bacteria from bacteriophages. During an infection, bacteriophages hijack transcription and translation, which could prevent antitoxin replenishment and release toxin, triggering what is called an "abortive infection". Similar protective effects have been observed with type I and type II toxin-antitoxin systems.
When bacteria are challenged with antibiotics, a small and distinct subpopulation of cells is able to withstand the treatment by a phenomenon dubbed as "persistence" (not to be confused with resistance). Due to their bacteriostatic properties, type II toxin-antitoxin systems have previously been thought to be responsible for persistence, by switching a fraction of the bacterial population to a dormant state. However, this hypothesis has been widely invalidated.
Toxin-antitoxin systems have been used as examples of selfish DNA as part of the gene centered view of evolution. It has been theorised that toxin-antitoxin loci serve only to maintain their own DNA, at the expense of the host organism. Thus, chromosomal toxin-antitoxin systems would serve no purpose and could be treated as "junk DNA". For example, the ccdAB system encoded in the chromosome of E. coli O157:H7 has been shown to be under negative selection, albeit at a slow rate due to its addictive properties.
Type I toxin-antitoxin systems rely on the base-pairing of complementary antitoxin RNA with the toxin mRNA. Translation of the mRNA is then inhibited either by degradation via RNase III or by occluding the Shine-Dalgarno sequence or ribosome binding site of the toxin mRNA. Often the toxin and antitoxin are encoded on opposite strands of DNA. The 5' or 3' overlapping region between the two genes is the area involved in complementary base-pairing, usually with between 19â€“23 contiguous base pairs.
Toxins of type I systems are small, hydrophobic proteins that confer toxicity by damaging cell membranes. Few intracellular targets of type I toxins have been identified, possibly due to the difficult nature of analysing proteins that are poisonous to their bacterial hosts.
Type I systems sometimes include a third component. In the case of the well-characterised hok/sok system, in addition to the hok toxin and sok antitoxin, there is a third gene, called mok. This open reading frame almost entirely overlaps that of the toxin, and the translation of the toxin is dependent on the translation of this third component. Thus the binding of antitoxin to toxin is sometimes a simplification, and the antitoxin in fact binds a third RNA, which then affects toxin translation.
|hok||sok||The original and best-understood type I toxin-antitoxin system (pictured), which stabilises plasmids in a number of gram-negative bacteria|||
|fst||RNAII||The first type I system to be identified in gram-positive bacteria|||
|tisB||istR||A chromosomal system induced in the SOS response|||
|ldrD||rdlD||A chromosomal system in Enterobacteriaceae|||
|flmA||flmB||A hok/sok homologue, which also stabilises the F plasmid|||
|ibs||sib||Discovered in E. coli intergenic regions, the antitoxin was originally named QUAD RNA|||
|txpA/brnT||ratA||Ensures the inheritance of the skin element during sporulation in Bacillus subtilis|||
|symE||symR||A chromosomal system induced in the SOS response|||
|XCV2162||ptaRNA1||A system identified in Xanthomonas campestris with erratic phylogenetic distribution.|||
Type II toxin-antitoxin systems are generally better-understood than type I. In this system a labile proteic antitoxin tightly binds and inhibits the activity of a stable toxin. The largest family of type II toxin-antitoxin systems is vapBC, which has been found through bioinformatics searches to represent between 37 and 42% of all predicted type II loci.Type II systems are organised in operons with the antitoxin protein typically being located upstream of the toxin, which helps to prevent expression of the toxin without the antitoxin. The proteins are typically around 100 amino acids in length, and exhibit toxicity in a number of ways: CcdB, for example, affects DNA replication by poisoning DNA gyrase whereas the MazF and RelE toxins are endoribonuclease that cleaves cellular mRNAs at specific sequence motifs. The most common toxic activity is the protein acting as an endonuclease, also known as an interferase.
A third protein can sometimes be involved in type II toxin-antitoxin systems. in the case of the Ï‰-Îµ-Î¶ (omega-epsilon-zeta) system, the omega protein is a DNA binding protein that negatively regulates the transcription of the whole system. Similarly, the paaR2 protein regulates the expression of the paaR2-paaA2-parE2 toxin-antitoxin system. Other toxin-antitoxin systems can be found with a chaperone as a third component. This chaperone is essential for proper folding of the antitoxin, thus making the antitoxin addicted to its cognate chaperone.
|ccdB||ccdA||Found on the F plasmid of Escherichia coli|||
|parE||parD||Found in multiple copies in Caulobacter crescentus|||
|mazF||mazE||Found in E. coli and in chromosomes of other bacteria|||
|yafO||yafN||A system induced by the SOS response to DNA damage in E. coli|||
|hicA||hicB||Found in archaea and bacteria|||
|kid||kis||Stabilises the R1 plasmid and is related to the CcdB/A system|||
|Î¶||Îµ||Found mostly in Gram-positive bacteria|||
|ataT||ataR||Found in enterohemorragic E. coli and Klebsiella spp.|||
|Symbol||ToxN, type III toxin-antitoxin system|
Type III toxin-antitoxin systems rely on direct interaction between a toxic protein and an RNA antitoxin. The toxic effects of the protein are neutralised by the RNA gene. One example is the ToxIN system from the bacterial plant pathogen Erwinia carotovora. The toxic ToxN protein is approximately 170 amino acids long and has been shown to be toxic to E. coli. The toxic activity of ToxN is inhibited by ToxI RNA, an RNA with 5.5 direct repeats of a 36 nucleotide motif (AGGTGATTTGCTACCTTTAAGTGCAGCTAGAAATTC). Crystallographic analysis of ToxIN has found that ToxN inhibition requires the formation of a trimeric ToxIN complex, whereby three ToxI monomers bind three ToxN monomers; the complex is held together by extensive protein-RNA interactions.
Type IV toxin-antitoxin systems are similar to type II systems, because they consist of two proteins. Unlike type II systems, the antitoxin in type IV toxin-antitoxin systems counteracts the activity of the toxin, and the two proteins do not directly interact.
ghoST is a type V toxin-antitoxin system, in which the antitoxin (GhoS) cleaves the ghoT mRNA. This system is regulated by a type II system, mqsRA.
The biotechnological applications of toxin-antitoxin systems have begun to be realised by several biotechnology organisations. A primary usage is in maintaining plasmids in a large bacterial cell culture. In an experiment examining the effectiveness of the hok/sok locus, it was found that segregational stability of an inserted plasmid expressing beta-galactosidase was increased by between 8 and 22 times compared to a control culture lacking a toxin-antitoxin system. In large-scale microorganism processes such as fermentation, progeny cells lacking the plasmid insert often have a higher fitness than those who inherit the plasmid and can outcompete the desirable microorganisms. A toxin-antitoxin system maintains the plasmid thereby maintaining the efficiency of the industrial process.
Ensuring a plasmid accepts an insert is a common problem of DNA cloning. Toxin-antitoxin systems can be used to positively select for only those cells that have taken up a plasmid containing the inserted gene of interest, screening out those that lack the inserted gene. An example of this application comes from the ccdB-encoded toxin, which has been incorporated into plasmid vectors. The gene of interest is then targeted to recombine into the ccdB locus, inactivating the transcription of the toxic protein. Thus, cells containing the plasmid but not the insert perish due to the toxic effects of CcdB protein, and only those that incorporate the insert survive.
Another example application involves both the CcdB toxin and CcdA antitoxin. CcdB is found in recombinant bacterial genomes and an inactivated version of CcdA is inserted into a linearised plasmid vector. A short extra sequence is added to the gene of interest that activates the antitoxin when the insertion occurs. This method ensures orientation-specific gene insertion.
Genetically modified organisms must be contained in a pre-defined area during research. Toxin-antitoxin systems can cause cell suicide in certain conditions, such as a lack of a lab-specific growth medium they would not encounter outside of the controlled laboratory set-up.
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- Mutschler H, Meinhart A (December 2011). "Îµ/Î¶ systems: their role in resistance, virulence, and their potential for antibiotic development". Journal of Molecular Medicine. 89 (12): 1183â€“94. doi:10.1007/s00109-011-0797-4. PMC 3218275. PMID 21822621.
- Hallez R, Geeraerts D, Sterckx Y, Mine N, Loris R, Van Melderen L (May 2010). "New toxins homologous to ParE belonging to three-component toxin-antitoxin systems in Escherichia coli O157:H7". Molecular Microbiology. 76 (3): 719â€“32. doi:10.1111/j.1365-2958.2010.07129.x. PMID 20345661.
- Bordes P, Cirinesi AM, Ummels R, Sala A, Sakr S, Bitter W, Genevaux P (May 2011). "SecB-like chaperone controls a toxin-antitoxin stress-responsive system in Mycobacterium tuberculosis". Proceedings of the National Academy of Sciences of the United States of America. 108 (20): 8438â€“43. doi:10.1073/pnas.1101189108. PMC 3100995. PMID 21536872.
- Fiebig A, Castro Rojas CM, Siegal-Gaskins D, Crosson S (July 2010). "Interaction specificity, toxicity and regulation of a paralogous set of ParE/RelE-family toxin-antitoxin systems". Molecular Microbiology. 77 (1): 236â€“51. doi:10.1111/j.1365-2958.2010.07207.x. PMC 2907451. PMID 20487277. (subscription required)
- Singletary LA, Gibson JL, Tanner EJ, McKenzie GJ, Lee PL, Gonzalez C, Rosenberg SM (December 2009). "An SOS-regulated type 2 toxin-antitoxin system". Journal of Bacteriology. 191 (24): 7456â€“65. doi:10.1128/JB.00963-09. PMC 2786605. PMID 19837801.
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- Blower TR, Fineran PC, Johnson MJ, Toth IK, Humphreys DP, Salmond GP (October 2009). "Mutagenesis and functional characterization of the RNA and protein components of the toxIN abortive infection and toxin-antitoxin locus of Erwinia". Journal of Bacteriology. 191 (19): 6029â€“39. doi:10.1128/JB.00720-09. PMC 2747886. PMID 19633081.
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- RASTA â€“ Rapid Automated Scan for Toxins and Antitoxins in Bacteria
This tab holds the annotation information that is stored in the Pfam database. As we move to using Wikipedia as our main source of annotation, the contents of this tab will be gradually replaced by the Wikipedia tab.
ParD-like antitoxin of type II bacterial toxin-antitoxin system Provide feedback
ParD-like antitoxin is a family of archaeal and bacterial proteins of a type II bacterial toxin-antitoxin system. Many of the cognate toxins for these molecules fall into family ParE-like_toxin, PF15781. Gene-pairs are expressed from the same operon, the toxin of the pair being expressed first, eg, for UniProtKB:Q3AQ93 and UniProtKB:Q3AQ94.
Internal database links
This tab holds annotation information from the InterPro database.
InterPro entry IPR021831
ParD-like antitoxin is a family of archaeal and bacterial proteins of a type II bacterial toxin-antitoxin system. Many of the cognate toxins for these molecules fall into family ParE-like_toxin, Pfam:PF15781. Gene-pairs are expressed from the same operon, the toxin of the pair being expressed first, eg, for UniProtKB: SWISSPROT and SWISSPROT .
Below is a listing of the unique domain organisations or architectures in which this domain is found. More...
The graphic that is shown by default represents the longest sequence with a given architecture. Each row contains the following information:
- the number of sequences which exhibit this architecture
a textual description of the architecture, e.g. Gla, EGF x 2, Trypsin.
This example describes an architecture with one
Gladomain, followed by two consecutive
EGFdomains, and finally a single
- a link to the page in the Pfam site showing information about the sequence that the graphic describes
- the UniProt description of the protein sequence
- the number of residues in the sequence
- the Pfam graphic itself.
Note that you can see the family page for a particular domain by clicking on the graphic. You can also choose to see all sequences which have a given architecture by clicking on the Show link in each row.
Finally, because some families can be found in a very large number of architectures, we load only the first fifty architectures by default. If you want to see more architectures, click the button at the bottom of the page to load the next set.
Loading domain graphics...
This superfamily contains many antitoxin families, all of which carry a ribbon-helix-helix DNA-binding motif with the beta-ribbon located in and recognising the major groove of operator DNA .
The clan contains the following 43 members:Arc BrnA_antitoxin CcdA CopG_antitoxin DndE DUF1778 DUF1902 DUF2540 DUF2610 DUF6290 DUF6364 HicB HicB-like_2 HicB_lk_antitox MatP_C MetJ MobC MobC_2 Omega_Repress ParB_C ParD ParD_antitoxin ParD_like ParG Plasmid_stab_B PSK_trans_fac RelB RepB-RCR_reg Repressor_Mnt RHH_1 RHH_3 RHH_4 RHH_5 RHH_6 RHH_7 RHH_8 RHH_9 SeqA_N TraY VAPB_antitox VapB_antitoxin VirC2 VirD1
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...
There are various ways to view or download the sequence alignments that we store. We provide several sequence viewers and a plain-text Stockholm-format file for download.
We make a range of alignments for each Pfam-A family:
- the curated alignment from which the HMM for the family is built
- the alignment generated by searching the sequence database using the HMM
- Representative Proteomes (RPs) at 15%, 35%, 55% and 75% co-membership thresholds
- alignment generated by searching the UniProtKB sequence database using the family HMM
You can see the alignments as HTML or in three different sequence viewers:
- a Java applet developed at the University of Dundee. You will need Java installed before running jalview
- an HTML page showing the whole alignment.Please note: full Pfam alignments can be very large. These HTML views are extremely large and often cause problems for browsers. Please use either jalview or the Pfam viewer if you have trouble viewing the HTML version
- an HTML-based representation of the alignment, coloured according to the posterior-probability (PP) values from the HMM. As for the standard HTML view, heatmap alignments can also be very large and slow to render.
You can download (or view in your browser) a text representation of a Pfam alignment in various formats:
You can also change the order in which sequences are listed in the alignment, change how insertions are represented, alter the characters that are used to represent gaps in sequences and, finally, choose whether to download the alignment or to view it in your browser directly.
You may find that large alignments cause problems for the viewers and the reformatting tool, so we also provide all alignments in Stockholm format. You can download either the plain text alignment, or a gzipped version of it.
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.
1Cannot generate PP/Heatmap alignments for seeds; no PP data available
Key: available, not generated, — not available.
Format an alignment
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.
You can also download a FASTA format file containing the full-length sequences for all sequences in the full alignment.
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...
If you find these logos useful in your own work, please consider citing the following article:
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.
|Seed source:||PFAM-B_670 (release 23.0)|
|Author:||Assefa S , Coggill P , Bateman A|
|Number in seed:||15|
|Number in full:||875|
|Average length of the domain:||73.80 aa|
|Average identity of full alignment:||31 %|
|Average coverage of the sequence by the domain:||80.68 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 61295632 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||11|
|Download:||download the raw HMM for this family|
Weight segments by...
Change the size of the sunburst
selected sequences to HMM
a FASTA-format file
- 0 sequences
- 0 species
This visualisation provides a simple graphical representation of the distribution of this family across species. You can find the original interactive tree in the More....
This chart is a modified "sunburst" visualisation of the species tree for this family. It shows each node in the tree as a separate arc, arranged radially with the superkingdoms at the centre and the species arrayed around the outermost ring.
How the sunburst is generated
The tree is built by considering the taxonomic lineage of each sequence that has a match to this family. For each node in the resulting tree, we draw an arc in the sunburst. The radius of the arc, its distance from the root node at the centre of the sunburst, shows the taxonomic level ("superkingdom", "kingdom", etc). The length of the arc represents either the number of sequences represented at a given level, or the number of species that are found beneath the node in the tree. The weighting scheme can be changed using the sunburst controls.
In order to reduce the complexity of the representation, we reduce the number of taxonomic levels that we show. We consider only the following eight major taxonomic levels:
Colouring and labels
Segments of the tree are coloured approximately according to their superkingdom. For example, archeal branches are coloured with shades of orange, eukaryotes in shades of purple, etc. The colour assignments are shown under the sunburst controls. Where space allows, the name of the taxonomic level will be written on the arc itself.
As you move your mouse across the sunburst, the current node will be highlighted. In the top section of the controls panel we show a summary of the lineage of the currently highlighed node. If you pause over an arc, a tooltip will be shown, giving the name of the taxonomic level in the title and a summary of the number of sequences and species below that node in the tree.
Anomalies in the taxonomy tree
There are some situations that the sunburst tree cannot easily handle and for which we have work-arounds in place.
Missing taxonomic levels
Some species in the taxonomic tree may not have one or more of the main eight levels that we display. For example, Bos taurus is not assigned an order in the NCBI taxonomic tree. In such cases we mark the omitted level with, for example, "No order", in both the tooltip and the lineage summary.
Unmapped species names
The tree is built by looking at each sequence in the full alignment for the family. We take the name of the species given by UniProt and try to map that to the full taxonomic tree from NCBI. In some cases, the name chosen by UniProt does not map to any node in the NCBI tree, perhaps because the chosen name is listed as a synonym or a misspelling in the NCBI taxonomy.
So that these nodes are not simply omitted from the sunburst tree, we group them together in a separate branch (or segment of the sunburst tree). Since we cannot determine the lineage for these unmapped species, we show all levels between the superkingdom and the species as "uncategorised".
Since we reduce the species tree to only the eight main taxonomic levels, sequences that are mapped to the sub-species level in the tree would not normally be shown. Rather than leave out these species, we map them instead to their parent species. So, for example, for sequences belonging to one of the Vibrio cholerae sub-species in the NCBI taxonomy, we show them instead as belonging to the species Vibrio cholerae.
Too many species/sequences
For large species trees, you may see blank regions in the outer layers of the sunburst. These occur when there are large numbers of arcs to be drawn in a small space. If an arc is less than approximately one pixel wide, it will not be drawn and the space will be left blank. You may still be able to get some information about the species in that region by moving your mouse across the area, but since each arc will be very small, it will be difficult to accurately locate a particular species.
The tree shows the occurrence of this domain across different species. More...
We show the species tree in one of two ways. For smaller trees we try to show an interactive representation, which allows you to select specific nodes in the tree and view them as an alignment or as a set of Pfam domain graphics.
Unfortunately we have found that there are problems viewing the interactive tree when the it becomes larger than a certain limit. Furthermore, we have found that Internet Explorer can become unresponsive when viewing some trees, regardless of their size. We therefore show a text representation of the species tree when the size is above a certain limit or if you are using Internet Explorer to view the site.
If you are using IE you can still load the interactive tree by clicking the "Generate interactive tree" button, but please be aware of the potential problems that the interactive species tree can cause.
For all of the domain matches in a full alignment, we count the number that are found on all sequences in the alignment. This total is shown in the purple box.
We also count the number of unique sequences on which each domain is found, which is shown in green. Note that a domain may appear multiple times on the same sequence, leading to the difference between these two numbers.
Finally, we group sequences from the same organism according to the NCBI code that is assigned by UniProt, allowing us to count the number of distinct sequences on which the domain is found. This value is shown in the pink boxes.
We use the NCBI species tree to group organisms according to their taxonomy and this forms the structure of the displayed tree. Note that in some cases the trees are too large (have too many nodes) to allow us to build an interactive tree, but in most cases you can still view the tree in a plain text, non-interactive representation. Those species which are represented in the seed alignment for this domain are highlighted.
You can use the tree controls to manipulate how the interactive tree is displayed:
- show/hide the summary boxes
- highlight species that are represented in the seed alignment
- expand/collapse the tree or expand it to a given depth
- select a sub-tree or a set of species within the tree and view them graphically or as an alignment
- save a plain text representation of the tree
Please note: for large trees this can take some time. While the tree is loading, you can safely switch away from this tab but if you browse away from the family page entirely, the tree will not be loaded.
AlphaFold Structure Predictions
The structural model below was generated by the Baker group with the trRosetta software using the Pfam UniProt multiple sequence alignment.
The InterPro website shows the contact map for the Pfam SEED alignment. Hovering or clicking on a contact position will highlight its connection to other residues in the alignment, as well as on the 3D structure.
- View the contact map and structural model in InterPro
- Download the model in PDB format
- Download all the data from the Pfam FTP site