Please note: this site relies heavily on the use of javascript. Without a javascript-enabled browser, this site will not function correctly. Please enable javascript and reload the page, or switch to a different browser.
199  structures 8775  species 0  interactions 59159  sequences 392  architectures

Family: GATase (PF00117)

Summary: Glutamine amidotransferase class-I

Pfam includes annotations and additional family information from a range of different sources. These sources can be accessed via the tabs below.

This is the Wikipedia entry entitled "Glutamine amidotransferase". More...

Glutamine amidotransferase Edit Wikipedia article

Glutamine amidotransferase class-I
PDB 1o1y EBI.jpg
crystal structure of putative glutamine amido transferase (tm1158) from thermotoga maritima at 1.70 a resolution
Pfam clanCL0014

In molecular biology, glutamine amidotransferases (GATase) are enzymes which catalyse the removal of the ammonia group from a glutamine molecule and its subsequent transfer to a specific substrate, thus creating a new carbon-nitrogen group on the substrate. This activity is found in a range of biosynthetic enzymes, including glutamine amidotransferase, anthranilate synthase component II, p-aminobenzoate, and glutamine-dependent carbamoyl-transferase (CPSase). Glutamine amidotransferase (GATase) domains can occur either as single polypeptides, as in glutamine amidotransferases, or as domains in a much larger multifunctional synthase protein, such as CPSase. On the basis of sequence similarities two classes of GATase domains have been identified: class-I (also known as trpG-type) and class-II (also known as purF-type).[1][2] Class-I GATase domains are defined by a conserved catalytic triad consisting of cysteine, histidine and glutamate. Class-I GATase domains have been found in the following enzymes: the second component of anthranilate synthase and 4-amino-4-deoxychorismate (ADC) synthase; CTP synthase; GMP synthase; glutamine-dependent carbamoyl-phosphate synthase; phosphoribosylformylglycinamidine synthase II; and the histidine amidotransferase hisH.


  1. ^ Weng ML, Zalkin H (July 1987). "Structural role for a conserved region in the CTP synthetase glutamine amide transfer domain". Journal of Bacteriology. 169 (7): 3023–8. PMC 212343. PMID 3298209.
  2. ^ Nyunoya H, Lusty CJ (August 1984). "Sequence of the small subunit of yeast carbamyl phosphate synthetase and identification of its catalytic domain". The Journal of Biological Chemistry. 259 (15): 9790–8. PMID 6086650.
This article incorporates text from the public domain Pfam and InterPro: IPR000991

This page is based on a Wikipedia article. The text is available under the Creative Commons Attribution/Share-Alike License.

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.

Glutamine amidotransferase class-I Provide feedback

No Pfam abstract.

Internal database links

External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR017926

Glutamine amidotransferase (GATase) enzymes catalyse the removal of the ammonia group from glutamine and then transfer this group to a substrate to form a new carbon-nitrogen group [ PUBMED:4355768 ]. The GATase domain exists either as a separate polypeptidic subunit or as part of a larger polypeptide fused in different ways to a synthase domain. Two classes of GATase domains have been identified [ PUBMED:3298209 , PUBMED:6086650 ]: class-I (also known as trpG-type or triad) and class-II (also known as purF-type or Ntn). Class-I (or type 1) GATase domains have been found in the following enzymes:

  • The second component of anthranilate synthase (AS) [ PUBMED:2679363 ]. AS catalyzes the biosynthesis of anthranilate from chorismate and glutamine. AS is generally a dimeric enzyme: the first component can synthesize anthranilate using ammonia rather than glutamine, whereas component II provides the GATase activity [ PUBMED:10449718 ]. In some bacteria and in fungi the GATase component of AS is part of a multifunctional protein that also catalyzes other steps of the biosynthesis of tryptophan.
  • The second component of 4-amino-4-deoxychorismate (ADC) synthase, a dimeric prokaryotic enzyme that functions in the pathway that catalyzes the biosynthesis of para-aminobenzoate (PABA) from chorismate and glutamine. The second component (gene pabA) provides the GATase activity [ PUBMED:2679363 ].
  • CTP synthase. CTP synthase catalyzes the final reaction in the biosynthesis of pyrimidine, the ATP-dependent formation of CTP from UTP and glutamine. CTP synthase is a single chain enzyme that contains two distinct domains; the GATase domain is in the C-terminal section [ PUBMED:3298209 ].
  • GMP synthase (glutamine-hydrolyzing). GMP synthase catalyzes the ATP-dependent formation of GMP from xanthosine 5'-phosphate and glutamine. GMP synthase is a single chain enzyme that contains two distinct domains; the GATase domain is in the N-terminal section [ PUBMED:2982857 , PUBMED:8548458 ].
  • Glutamine-dependent carbamoyl-phosphate synthase (GD-CPSase); an enzyme involved in both arginine and pyrimidine biosynthesis and which catalyzes the ATP-dependent formation of carbamoyl phosphate from glutamine and carbon dioxide. In bacteria GD-CPSase is composed of two subunits: the large chain (gene carB) provides the CPSase activity, while the small chain (gene carA) provides the GATase activity. In yeast the enzyme involved in arginine biosynthesis is also composed of two subunits: CPA1 (GATase), and CPA2 (CPSase). In most eukaryotes, the first three steps of pyrimidine biosynthesis are catalyzed by a large multifunctional enzyme (called URA2 in yeast, rudimentary in Drosophila, and CAD in mammals). The GATase domain is located at the N-terminal extremity of this polyprotein [ PUBMED:8098212 ].
  • Phosphoribosylformylglycinamidine synthase, an enzyme that catalyzes the fourth step in the de novo biosynthesis of purines. In some species of bacteria and rchaea, FGAM synthase II is composed of two subunits: a small chain (gene purQ) which provides the GATase activity and a large chain (gene purL) which provides the aminator activity. In eukaryotes and Gram-negative bacteria a single polypeptide (large type of purL) contains a FGAM synthethase domain and the GATase as the C-terminal domain [ PUBMED:15301531 ].
  • Imidazole glycerol phosphate synthase subunit hisH, an enzyme that catalyzes the fifth step in the biosynthesis of histidine.
A triad of conserved Cys-His-Glu forms the active site, wherein the catalytic cysteine is essential for the amidotransferase activity [ PUBMED:8548458 , PUBMED:9575335 ]. Different structures show that the active site Cys of type 1 GATase is located at the tip of a nucleophile elbow.

Domain organisation

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

Loading domain graphics...

Pfam Clan

This family is a member of clan Glutaminase_I (CL0014), which has the following description:

Most members of this clan are glutaminase enzymes. This superfamily is shown to be related in [1]. The clan also contains the DJ-1/PfpI family that includes the peptidase PfpI that has a catalytic Cys-His-Glu triad that differs from the class I GAT Cys-His-Glu triad.

The clan contains the following 18 members:

ABC_transp_aux BPL_N Catalase_C DJ-1_PfpI DUF4159 GATase GATase1_like GATase_3 GATase_5 Glyco_hydro_42M HTS LBP_M Peptidase_C26 Peptidase_S51 Peptidase_S66 SNO ThiJ_like ThuA


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...

View options

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.

Representative proteomes UniProt
Jalview View  View  View  View  View  View  View 
HTML View             
PP/heatmap 1            

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

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

Format an alignment

Representative proteomes UniProt

Download options

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.

Representative proteomes UniProt
Raw Stockholm Download   Download   Download   Download   Download   Download    
Gzipped 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...


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: Prosite
Previous IDs: none
Type: Domain
Sequence Ontology: SO:0000417
Author: Sonnhammer ELL
Number in seed: 96
Number in full: 59159
Average length of the domain: 191.00 aa
Average identity of full alignment: 22 %
Average coverage of the sequence by the domain: 43.11 %

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 22.8 22.8
Trusted cut-off 22.8 22.8
Noise cut-off 22.7 22.7
Model length: 191
Family (HMM) version: 30
Download: download the raw HMM for this family

Species distribution

Sunburst controls


Weight segments by...

Change the size of the sunburst


Colour assignments

Archea Archea Eukaryota Eukaryota
Bacteria Bacteria Other sequences Other sequences
Viruses Viruses Unclassified Unclassified
Viroids Viroids Unclassified sequence Unclassified sequence


Align selected sequences to HMM

Generate a FASTA-format file

Clear selection

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...

Loading sunburst data...

Tree controls


The tree shows the occurrence of this domain across different species. More...


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.


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 GATase domain has been found. There are 199 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...