Summary: Adenosine-deaminase (editase) domain
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Adenosine deaminase Edit Wikipedia article
|, entrez:100, Adenosine deaminase|
|RNA expression pattern|
crystal structure of plasmodium yoelii adenosine deaminase (py02076)
|Adenosine deaminase (editase) domain|
|Adenosine/AMP deaminase N-terminal|
Adenosine deaminase (also known as adenosine aminohydrolase, or ADA) is an enzyme (EC 188.8.131.52) involved in purine metabolism. It is needed for the breakdown of adenosine from food and for the turnover of nucleic acids in tissues.
ADA exists in both small form (as a monomer) and large form (as a dimer-complex). In the monomer form, the enzyme is a polypeptide chain, folded into eight strands of parallel α/β barrels, which surround a central deep pocket that is the active site. In addition to the eight central β-barrels and eight peripheral α-helices, ADA also contains five additional helices: residues 19-76 fold into three helices, located between β1 and α1 folds; and two antiparallel carboxy-terminal helices are located across the amino-terminal of the β-barrel.
The ADA active site contains a zinc ion, which is located in the deepest recess of the active site and coordinated by five atoms from His15, His17, His214, Asp295, and the substrate. Zinc is the only cofactor necessary for activity.
The substrate, adenosine, is stabilized and bound to the active site by nine hydrogen bonds. The carboxyl group of Glu217, roughly coplanar with the substrate purine ring, is in position to form a hydrogen bond with N1 of the substrate. The carboxyl group of Asp296, also coplanar with the substrate purine ring, forms hydrogen bond with N7 of the substrate. The NH group of Gly184 is in position to form a hydrogen bond with N3 of the substrate. Asp296 forms bonds both with the Zn2+ ion as well as with 6-OH of the substrate. His238 also hydrogen bonds to substrate 6-OH. The 3'-OH of the substrate ribose forms a hydrogen bond with Asp19, while the 5'-OH forms a hydrogen bond with His17. Two further hydrogen bonds are formed to water molecules, at the opening of the active site, by the 2'-OH and 3'-OH of the substrate.
Due to the recessing of the active site inside the enzyme, the substrate, once bound, is almost completely sequestered from solvent. The surface exposure of the substrate to solvent when bound is 0.5% the surface exposure of the substrate in the free state.
Mechanism of catalysis
Two proposed mechanisms exist for ADA-catalyzed deamination: 1) stereospecific addition-elimination via tetrahedral intermediate or 2) an SN2 reaction. By either mechanism, Zn2+ as a strong electrophile activates a water molecule, which is deprotonated by the basic Asp295 to form the attacking hydroxide. His238 orients the water molecule and stabilizes the charge of the attacking hydroxide. Glu217 is protonated to donate a proton to N1 of the substrate.
Competitive inhibition has been observed for ADA, where the product inosine acts at the competitive inhibitor to enzymatic activity.
ADA is considered one of the key enzymes of purine metabolism. The enzyme has been found in bacteria, plants, invertebrates, vertebrates, and mammals, with high conservation of amino acid sequence. The high degree of amino acid sequence conservation suggests the crucial nature of ADA in the purine salvage pathway.
Primarily, ADA in humans is involved in the development and maintenance of the immune system. However, ADA association has also been observed with epithelial cell differentiation, neurotransmission, and gestation maintenance. It has also been proposed that ADA, in addition to adenosine breakdown, stimulates release of excitatory amino acids and is necessary to the coupling of A1 adenosine receptors and heterotrimeric G proteins. Adenosine deaminase deficiency leads to pulmonary fibrosis, suggesting that chronic exposure to high levels of adenosine can exacerbate inflammation responses rather than suppressing them. It has also been recognized that adenosine deaminase protein and activity is upregulated in mouse hearts that overexpress HIF-1 alpha, which in part explains the attenuated levels of adenosine in HIF-1 alpha expressing hearts during ischemic stress.
Some mutations in the gene for adenosine deaminase cause it not to be expressed. The resulting deficiency is one cause of (SCID), particularly of autosomal recessive inheritance. Deficient levels of ADA have also been associated with pulmonary inflammation, thymic cell death, and defective T-cell receptor signaling.
Conversely, mutations causing this enzyme to be overexpressed are one cause of .
There are 2 isoforms of ADA: ADA1 and ADA2.
- ADA1 is found in most body cells, particularly lymphocytes and macrophages, where it is present not only in the cytosol and nucleus but also as the ecto- form on the cell membrane attached to dipeptidyl peptidase-4 (aka, CD26). ADA1 is involved mostly in intracellular activity, and exists both in small form (monomer) and large form (dimer). The interconversion of small to large forms is regulated by a 'conversion factor' in the lung.
- ADA2 was first identified in human spleen. It was subsequently found in other tissues including the macrophage where it co-exists with ADA1. The two isoforms regulate the ratio of adenosine to deoxyadenosine potentiating the killing of parasites. ADA2 is found predominantly in the human plasma and serum, and exists solely as a homodimer.
ADA2 is the predominant form present in human blood plasma and is increased in many diseases, particularly those associated with the immune system: for example rheumatoid arthritis, psoriasis, and sarcoidosis. The plasma ADA2 isoform is also increased in most cancers. ADA2 is not ubiquitous but co-exists with ADA1 only in monocytes-macrophages.
Total plasma ADA can be measured using high performance liquid chromatography or enzymatic or colorimetric techniques. Perhaps the simplest system is the measurement of the ammonia released from adenosine when broken down to inosine. After incubation of plasma with a buffered solution of adenosine the ammonia is reacted with a Berthelot reagent to form a blue colour which is proportionate to the amount of enzyme activity. To measure ADA2, erythro-9-(2-hydroxy-3-nonyl) adenine (EHNA) is added prior to incubation so as to inhibit the enzymatic activity of ADA1. It is the absence of ADA1 that causes SCID.
- "Human PubMed Reference:".
- "Mouse PubMed Reference:".
- Wilson DK, Rudolph FB, Quiocho FA (May 1991). "Atomic structure of adenosine deaminase complexed with a transition-state analog: understanding catalysis and immunodeficiency mutations". Science. 252 (5010): 1278–1284. doi:10.1126/science.1925539. PMID 1925539.
- Cristalli G, Costanzi S, Lambertucci C, Lupidi G, Vittori S, Volpini R, Camaioni E (Mar 2001). "Adenosine deaminase: functional implications and different classes of inhibitors". Medicinal Research Reviews. 21 (2): 105–128. doi:10.1002/1098-1128(200103)21:2<105::AID-MED1002>3.0.CO;2-U. PMID 11223861.
- Daddona PE, Kelley WN (Jan 1977). "Human adenosine deaminase. Purification and subunit structure". The Journal of Biological Chemistry. 252 (1): 110–115. PMID 13062.
- Glader BE, Backer K, Diamond LK (Dec 1983). "Elevated erythrocyte adenosine deaminase activity in congenital hypoplastic anemia". The New England Journal of Medicine. 309 (24): 1486–1490. doi:10.1056/NEJM198312153092404. PMID 6646173.
- Saboury AA, Divsalar A, Jafari GA, Moosavi-Movahedi AA, Housaindokht MR, Hakimelahi GH (May 2002). "A product inhibition study on adenosine deaminase by spectroscopy and calorimetry". Journal of Biochemistry and Molecular Biology. 35 (3): 302–305. doi:10.5483/BMBRep.2002.35.3.302. PMID 12297022.
- Moriwaki Y, Yamamoto T, Higashino K (Oct 1999). "Enzymes involved in purine metabolism--a review of histochemical localization and functional implications". Histology and Histopathology. 14 (4): 1321–1340. PMID 10506947.
- Blackburn MR (2003). "Too much of a good thing: adenosine overload in adenosine-deaminase-deficient mice". Trends in Pharmacological Sciences. 24 (2): 66–70. doi:10.1016/S0165-6147(02)00045-7. PMID 12559769.
- Wu J, Bond C, Chen P, Chen M, Li Y, Shohet RV, Wright G (2015). "HIF-1α in the heart: remodeling nucleotide metabolism". Journal of Molecular and Cellular Cardiology. 82: 194–200. doi:10.1016/j.yjmcc.2015.01.014. PMC . PMID 25681585.
- Sanchez JJ, Monaghan G, Børsting C, Norbury G, Morling N, Gaspar HB (May 2007). "Carrier frequency of a nonsense mutation in the adenosine deaminase (ADA) gene implies a high incidence of ADA-deficient severe combined immunodeficiency (SCID) in Somalia and a single, common haplotype indicates common ancestry". Annals of Human Genetics. 71 (Pt 3): 336–47. doi:10.1111/j.1469-1809.2006.00338.x. PMID 17181544.
- Blackburn MR, Kellems RE (2005). "Adenosine deaminase deficiency: metabolic basis of immune deficiency and pulmonary inflammation". Advances in Immunology. Advances in Immunology. 86: 1–41. doi:10.1016/S0065-2776(04)86001-2. ISBN 9780120044863. PMID 15705418.
- Apasov SG, Blackburn MR, Kellems RE, Smith PT, Sitkovsky MV (Jul 2001). "Adenosine deaminase deficiency increases thymic apoptosis and causes defective T cell receptor signaling". The Journal of Clinical Investigation. 108 (1): 131–141. doi:10.1172/JCI10360. PMC . PMID 11435465.
- Chottiner EG, Cloft HJ, Tartaglia AP, Mitchell BS (Mar 1987). "Elevated adenosine deaminase activity and hereditary hemolytic anemia. Evidence for abnormal translational control of protein synthesis". The Journal of Clinical Investigation. 79 (3): 1001–5. doi:10.1172/JCI112866. PMC . PMID 3029177.
- Persico AM, Militerni R, Bravaccio C, Schneider C, Melmed R, Trillo S, Montecchi F, Palermo MT, Pascucci T, Puglisi-Allegra S, Reichelt KL, Conciatori M, Baldi A, Keller F (Dec 2000). "Adenosine deaminase alleles and autistic disorder: case-control and family-based association studies". American Journal of Medical Genetics. 96 (6): 784–90. doi:10.1002/1096-8628(20001204)96:6<784::AID-AJMG18>3.0.CO;2-7. PMID 11121182.
- Cowan MJ, Brady RO, Widder KJ (Feb 1986). "Elevated erythrocyte adenosine deaminase activity in patients with acquired immunodeficiency syndrome". Proceedings of the National Academy of Sciences of the United States of America. 83 (4): 1089–1091. doi:10.1073/pnas.83.4.1089. PMC . PMID 3006027.
- Schrader WP, Stacy AR (Sep 1977). "Purification and subunit structure of adenosine deaminase from human kidney". The Journal of Biological Chemistry. 252 (18): 6409–6415. PMID 893413.
- Schrader WP, Pollara B, Meuwissen HJ (Jan 1978). "Characterization of the residual adenosine deaminating activity in the spleen of a patient with combined immunodeficiency disease and adenosine deaminase deficiency". Proceedings of the National Academy of Sciences of the United States of America. 75 (1): 446–50. doi:10.1073/pnas.75.1.446. PMC . PMID 24216.
- Zavialov AV, Engström A (Oct 2005). "Human ADA2 belongs to a new family of growth factors with adenosine deaminase activity". The Biochemical Journal. 391 (Pt 1): 51–57. doi:10.1042/BJ20050683. PMC . PMID 15926889.
- Jiménez Castro D, Díaz Nuevo G, Pérez-Rodríguez E, Light RW (2003). "Diagnostic value of adenosine deaminase in nontuberculous lymphocytic pleural effusions" (PDF). Eur. Respir. J. 21 (2): 220–4. doi:10.1183/09031936.03.00051603. PMID 12608433.
- Brunicardi F, Andersen D, Billiar T, Dunn D, Hunter J, Pollock RE (2005). "Chapter 18, question 16". Schwartz's principles of surgery (8th ed.). New York: McGraw-Hill Professional. ISBN 978-0071410908.
- da Cunha JG (1992). "[Adenosine deaminase. A pluridisciplinary enzyme]". Acta Médica Portuguesa. 4 (6): 315–23. PMID 1807098.
- Franco R, Casadó V, Ciruela F, Saura C, Mallol J, Canela EI, Lluis C (Jul 1997). "Cell surface adenosine deaminase: much more than an ectoenzyme". Progress in Neurobiology. 52 (4): 283–94. doi:10.1016/S0301-0082(97)00013-0. PMID 9247966.
- Valenzuela A, Blanco J, Callebaut C, Jacotot E, Lluis C, Hovanessian AG, Franco R (1997). "HIV-1 envelope gp120 and viral particles block adenosine deaminase binding to human CD26". Advances in Experimental Medicine and Biology. 421: 185–92. doi:10.1007/978-1-4757-9613-1_24. PMID 9330696.
- Moriwaki Y, Yamamoto T, Higashino K (Oct 1999). "Enzymes involved in purine metabolism--a review of histochemical localization and functional implications". Histology and Histopathology. 14 (4): 1321–40. PMID 10506947.
- Hirschhorn R (1993). "Identification of two new missense mutations (R156C and S291L) in two ADA- SCID patients unusual for response to therapy with partial exchange transfusions". Human Mutation. 1 (2): 166–8. doi:10.1002/humu.1380010214. PMID 1284479.
- Berkvens TM, van Ormondt H, Gerritsen EJ, Khan PM, van der Eb AJ (Aug 1990). "Identical 3250-bp deletion between two AluI repeats in the ADA genes of unrelated ADA-SCID patients". Genomics. 7 (4): 486–90. doi:10.1016/0888-7543(90)90190-6. PMID 1696926.
- Aran JM, Colomer D, Matutes E, Vives-Corrons JL, Franco R (Aug 1991). "Presence of adenosine deaminase on the surface of mononuclear blood cells: immunochemical localization using light and electron microscopy". The Journal of Histochemistry and Cytochemistry. 39 (8): 1001–8. doi:10.1177/39.8.1856451. PMID 1856451.
- Bielat K, Tritsch GL (Apr 1989). "Ecto-enzyme activity of human erythrocyte adenosine deaminase". Molecular and Cellular Biochemistry. 86 (2): 135–42. doi:10.1007/BF00222613. PMID 2770711.
- Hirschhorn R, Tzall S, Ellenbogen A, Orkin SH (Feb 1989). "Identification of a point mutation resulting in a heat-labile adenosine deaminase (ADA) in two unrelated children with partial ADA deficiency". The Journal of Clinical Investigation. 83 (2): 497–501. doi:10.1172/JCI113909. PMC . PMID 2783588.
- Murray JL, Perez-Soler R, Bywaters D, Hersh EM (Jan 1986). "Decreased adenosine deaminase (ADA) and 5'nucleotidase (5NT) activity in peripheral blood T cells in Hodgkin disease". American Journal of Hematology. 21 (1): 57–66. doi:10.1002/ajh.2830210108. PMID 3010705.
- Wiginton DA, Kaplan DJ, States JC, Akeson AL, Perme CM, Bilyk IJ, Vaughn AJ, Lattier DL, Hutton JJ (Dec 1986). "Complete sequence and structure of the gene for human adenosine deaminase". Biochemistry. 25 (25): 8234–44. doi:10.1021/bi00373a017. PMID 3028473.
- Akeson AL, Wiginton DA, Dusing MR, States JC, Hutton JJ (Nov 1988). "Mutant human adenosine deaminase alleles and their expression by transfection into fibroblasts". The Journal of Biological Chemistry. 263 (31): 16291–6. PMID 3182793.
- Glader BE, Backer K (Feb 1988). "Elevated red cell adenosine deaminase activity: a marker of disordered erythropoiesis in Diamond-Blackfan anaemia and other haematologic diseases". British Journal of Haematology. 68 (2): 165–8. doi:10.1111/j.1365-2141.1988.tb06184.x. PMID 3348976.
- Petersen MB, Tranebjaerg L, Tommerup N, Nygaard P, Edwards H (Feb 1987). "New assignment of the adenosine deaminase gene locus to chromosome 20q13 X 11 by study of a patient with interstitial deletion 20q". Journal of Medical Genetics. 24 (2): 93–6. doi:10.1136/jmg.24.2.93. PMC . PMID 3560174.
- Orkin SH, Goff SC, Kelley WN, Daddona PE (Apr 1985). "Transient expression of human adenosine deaminase cDNAs: identification of a nonfunctional clone resulting from a single amino acid substitution". Molecular and Cellular Biology. 5 (4): 762–7. PMC . PMID 3838797.
- Valerio D, Duyvesteyn MG, Dekker BM, Weeda G, Berkvens TM, van der Voorn L, van Ormondt H, van der Eb AJ (Feb 1985). "Adenosine deaminase: characterization and expression of a gene with a remarkable promoter". The EMBO Journal. 4 (2): 437–43. PMC . PMID 3839456.
- Bonthron DT, Markham AF, Ginsburg D, Orkin SH (Aug 1985). "Identification of a point mutation in the adenosine deaminase gene responsible for immunodeficiency". The Journal of Clinical Investigation. 76 (2): 894–7. doi:10.1172/JCI112050. PMC . PMID 3839802.
- Daddona PE, Shewach DS, Kelley WN, Argos P, Markham AF, Orkin SH (Oct 1984). "Human adenosine deaminase. cDNA and complete primary amino acid sequence". The Journal of Biological Chemistry. 259 (19): 12101–6. PMID 6090454.
- Valerio D, Duyvesteyn MG, Meera Khan P, Geurts van Kessel A, de Waard A, van der Eb AJ (Nov 1983). "Isolation of cDNA clones for human adenosine deaminase". Gene. 25 (2–3): 231–40. doi:10.1016/0378-1119(83)90227-5. PMID 6198240.
- ADA human gene location in the UCSC Genome Browser.
- ADA human gene details in the UCSC Genome Browser.
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.
Adenosine-deaminase (editase) domain Provide feedback
Adenosine deaminases acting on RNA (ADARs) can deaminate adenosine to form inosine. In long double-stranded RNA, this process is non-specific; it occurs site-specifically in RNA transcripts. The former is important in defence against viruses, whereas the latter may affect splicing or untranslated regions. They are primarily nuclear proteins, but a longer isoform of ADAR1 is found predominantly in the cytoplasm. ADARs are derived from the Tad1-like tRNA deaminases that are present across eukaryotes. These in turn belong to the nucleotide/nucleic acid deaminase superfamily and are characterized by a distinct insert between the two conserved cysteines that are involved in binding zinc .
Iyer LM, Zhang D, Rogozin IB, Aravind L;, Nucleic Acids Res. 2011; [Epub ahead of print]: Evolution of the deaminase fold and multiple origins of eukaryotic editing and mutagenic nucleic acid deaminases from bacterial toxin systems. PUBMED:21890906 EPMC:21890906
External database links
This tab holds annotation information from the InterPro database.
InterPro entry IPR002466
Editase (EC) are enzymes that alter mRNA by catalyzing the site-selective deamination of adenosine residue into inosine residue. The editase domain contains the active site and binds three Zn atoms [PUBMED:9159072].
Several editases share a common global arrangement of domains, from N to C terminus: two 'double-stranded RNA-specific adenosine deaminase' (DRADA) repeat domains (INTERPRO), followed by three 'double-stranded RNA binding' (DsRBD) domains, followed by the editase domain. Other editases have a simplified domains structure with no DRADA_REP and possibly fewer DSRBD domains. Editase that deaminate cytidine are not detected by this signature.
The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.
|Molecular function||RNA binding (GO:0003723)|
|adenosine deaminase activity (GO:0004000)|
|Biological process||RNA processing (GO:0006396)|
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This clan contains both free nucleotide and nucleic acid deaminases that act on adenosine, cytosine, guanine and cytidine, and are collectively known as the deaminase superfamily. The conserved fold consists of a three-layered alpha/beta/alpha structure with 3 helices and 4 strands in the 2134 order [1,2].This superfamily is further divided into two major divisions based on the presence of a helix (helix-4) that renders the terminal strands (strands 4 and 5) either parallel to each other in its presence, or anti-parallel in its absence . Structurally, the deaminase-like fold is present in four other superfamilies including the JAB-like metalloproteins, the C-terminal AICAR transformylase-catalyzing domains of PurH, Tm1506 and the formate dehydrogenase accessory subunit FdhD. The active site of the deaminases is composed of three residues that coordinate a zinc ion between conserved helices 2 and 3. The residues are typically found as [HCD]xE and CxxC motifs at the beginning of helices 2 and 3. The zinc ion activates a water molecule, which forms a tetrahderal intermediate with the carbon atom that is linked to the amine group. This is followed by deamination of the base.
The clan contains the following 18 members:A_deamin AICARFT_IMPCHas APOBEC_C APOBEC_N Bd3614-deam dCMP_cyt_deam_1 dCMP_cyt_deam_2 DYW_deaminase FdhD-NarQ LmjF365940-deam MafB19-deam OTT_1508_deam Pput2613-deam SCP1201-deam TM1506 Toxin-deaminase XOO_2897-deam YwqJ-deaminase
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1Cannot generate PP/Heatmap alignments for seeds; no PP data available
Key: available, not generated, — not available.
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|Author:||Mian N, Bateman A, Iyer LM, Zhang D, Aravind L|
|Number in seed:||100|
|Number in full:||1501|
|Average length of the domain:||285.20 aa|
|Average identity of full alignment:||26 %|
|Average coverage of the sequence by the domain:||54.53 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 26740544 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||17|
|Download:||download the raw HMM for this family|
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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.
There is 1 interaction for this family. More...
We determine these interactions using iPfam, which considers the interactions between residues in three-dimensional protein structures and maps those interactions back to Pfam families. You can find more information about the iPfam algorithm in the journal article that accompanies the website.
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 A_deamin domain has been found. There are 10 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.
Loading structure mapping...