Summary: AICARFT/IMPCHase bienzyme
The Pfam group coordinates the annotation of Pfam families in Wikipedia, but we have not yet assigned a Wikipedia article to this family. If you think that a particular Wikipedia article provides good annotation, please let us know.
AICARFT/IMPCHase bienzyme Provide feedback
This is a family of bifunctional enzymes catalysing the last two steps in de novo purine biosynthesis. The bifunctional enzyme is found in both prokaryotes and eukaryotes. The second last step is catalysed by 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase EC:184.108.40.206 (AICARFT), this enzyme catalyses the formylation of AICAR with 10-formyl-tetrahydrofolate to yield FAICAR and tetrahydrofolate . This is catalysed by a pair of C-terminal deaminase fold domains in the protein  where the active site is formed by the dimeric interface of two monomeric units . The last step is catalysed by the N-terminal IMP (Inosine monophosphate) cyclohydrolase domain EC:220.127.116.11 (IMPCHase), cyclizing FAICAR (5-formylaminoimidazole-4-carboxamide ribonucleotide) to IMP .
Akira T, Komatsu M, Nango R, Tomooka A, Konaka K, Yamauchi M, Kitamura Y, Nomura S, Tsukamoto I; , Gene 1997;197:289-293.: Molecular cloning and expression of a rat cDNA encoding 5- aminoimidazole-4-carboxamide ribonucleotide formyltransferase/IMP cyclohydrolase [published erratum appears in Gene 1998 Feb 27;208(2):337] PUBMED:9332377 EPMC:9332377
Rayl EA, Moroson BA, Beardsley GP; , J Biol Chem 1996;271:2225-2233.: The human purH gene product, 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase/IMP cyclohydrolase. Cloning, sequencing, expression, purification, kinetic analysis, and domain mapping. PUBMED:8567683 EPMC:8567683
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 IPR002695
This is a family of bifunctional enzymes catalysing the last two steps in de novo purine biosynthesis. The bifunctional enzyme is found in both prokaryotes and eukaryotes. The second last step is catalysed by 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase EC (AICARFT), this enzyme catalyses the formylation of AICAR with 10-formyl-tetrahydrofolate to yield FAICAR and tetrahydrofolate [PUBMED:9332377]. The last step is catalysed by IMP (Inosine monophosphate) cyclohydrolase EC (IMPCHase), cyclizing FAICAR (5-formylaminoimidazole-4-carboxamide ribonucleotide) to IMP [PUBMED:9332377].
The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.
|Molecular function||phosphoribosylaminoimidazolecarboxamide formyltransferase activity (GO:0004643)|
|IMP cyclohydrolase activity (GO:0003937)|
|Biological process||purine nucleotide biosynthetic process (GO:0006164)|
- 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
- the UniProt description of the protein sequence
- the number of residues in the sequence
- the Pfam graphic itself.
Loading domain graphics...
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 17 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 Toxin-deaminase XOO_2897-deam YwqJ-deaminase
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 NCBI sequence database using the family HMM
- alignment generated by searching the metagenomics sequence database using the family HMM
You can see the alignments as HTML or in three different sequence viewers:
- Pfam viewer
- an HTML-based viewer that uses DAS to retrieve alignment fragments on request
1Cannot generate PP/Heatmap alignments for seeds; no PP data available
Key: available, not generated, — not available.
Format an alignment
If you find these logos useful in your own work, please consider citing the following article:
Note: You can also download the data file for the tree.
Curation and family details
|Seed source:||Pfam-B_1613 (release 4.2)|
|Author:||Bashton M, Bateman A, Iyer LM, Zhang D, Aravind L|
|Number in seed:||778|
|Number in full:||19829|
|Average length of the domain:||302.00 aa|
|Average identity of full alignment:||47 %|
|Average coverage of the sequence by the domain:||60.54 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 80369284 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||14|
|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
How the sunburst is generated
Colouring and labels
Anomalies in the taxonomy tree
Missing taxonomic levels
Unmapped species names
Too many species/sequences
The tree shows the occurrence of this domain across different species. More...
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
There are 3 interactions 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 AICARFT_IMPCHas domain has been found. There are 36 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 seqence.
Loading structure mapping...