Summary
PP-loop superfamily
This superfamily of proteins are known as the PP-loop after ATP PyroPhosphatase domain. The superfamily was initially identified as a conserved amino acid sequence motif in four distinct groups of enzymes that catalyse the hydrolysis of the alpha-beta phosphate bond of ATP, namely GMP synthetases, argininosuccinate synthetases, asparagine synthetases, and ATP sulfurylases [2].
This clan contains 12 families and the total number of domains in the clan is 31204.
Literature references
- Aravind L, Anantharaman V, Koonin EV; , Proteins 2002;48:1-14.: Monophyly of class I aminoacyl tRNA synthetase, USPA, ETFP, photolyase, and PP-ATPase nucleotide-binding domains: implications for protein evolution in the RNA. 12012333
- Bork P, Koonin EV; , Proteins 1994;20:347-355.: A P-loop-like motif in a widespread ATP pyrophosphatase domain: implications for the evolution of sequence motifs and enzyme activity. 7731953
Members
This clan contains the following 12 member families:
Arginosuc_synth Asn_synthase ATP_bind_3 ATP_bind_4 DNA_photolyase ETF ExsB NAD_synthase PAPS_reduct ThiI tRNA_Me_trans UspExternal database links
| CATH: | 3.40.50.610 |
| SCOP: | 52410 |
Domain organisation
Below is a listing of the unique domain organisations or architectures from this clan. More...
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Alignments
The table below shows the number of occurrences of each domain throughout the sequence database. More...
| Pfam family | Num. domains | Alignment |
|---|---|---|
| Usp (PF00582) | 9002 (28.8%) | View |
| NAD_synthase (PF02540) | 3426 (11.0%) | View |
| ETF (PF01012) | 3360 (10.8%) | View |
| ATP_bind_3 (PF01171) | 2827 (9.1%) | View |
| PAPS_reduct (PF01507) | 2597 (8.3%) | View |
| Asn_synthase (PF00733) | 2556 (8.2%) | View |
| tRNA_Me_trans (PF03054) | 1807 (5.8%) | View |
| DNA_photolyase (PF00875) | 1639 (5.3%) | View |
| Arginosuc_synth (PF00764) | 1559 (5.0%) | View |
| ExsB (PF06508) | 1133 (3.6%) | View |
| ThiI (PF02568) | 922 (3.0%) | View |
| ATP_bind_4 (PF01902) | 376 (1.2%) | View |
| Total: 12 | Total: 31204 | Clan alignment |
Please note: Clan alignments can be very large and can cause problems for some browsers. Read the note above before viewing.
Family relationships
This diagram shows the relationships between members of this clan. More...
Species distribution
Tree controls
HideThis tree shows the occurrence of the domains in this clan across different species. More...
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Interactions
There are 23 interactions for this clan. More...
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 MSD group, to allow us to map Pfam domains onto UniProt three-dimensional structures. The table below shows the mapping between the Pfam families in this clan, the corresponding UniProt entries, and the region of the three-dimensional structures that are available for that sequence.
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