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1774  structures 8902  species 0  interactions 30475  sequences 245  architectures

Clan: HAS-barrel (CL0275)


HAS-barrel superfamily Add an annotation

The HAS barrel is named after HerA-ATP Synthase. In ATP synthases, this domain is implicated in the assembly of the catalytic toroid and docking of accessory subunits, such as the subunit of the ATP synthase complex. Similar roles in docking of the functional partner, the NurA nuclease, and assembly of the HerA toroid complex appear likely for the HAS-barrel of the HerA family [1].

This clan contains 2 families and the total number of domains in the clan is 30475. The clan was built by A Bateman.

Literature references

  1. Iyer LM, Makarova KS, Koonin EV, Aravind L; , Nucleic Acids Res. 2004;32:5260-5279.: Comparative genomics of the FtsK-HerA superfamily of pumping ATPases: implications for the origins of chromosome segregation, cell division and viral capsid packaging. PUBMED:15466593 EPMC:15466593


This clan contains the following 2 member families:

ATP-synt_ab_N HAS-barrel

Domain organisation

Below is a listing of the unique domain organisations or architectures from this clan. More...

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The table below shows the number of occurrences of each domain throughout the sequence database. More...

Pfam family Num. domains Alignment
ATP-synt_ab_N (PF02874) 30187 (99.1%) View
HAS-barrel (PF09378) 288 (0.9%) View
Total: 2 Total: 30475 Clan alignment

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Family relationships

This diagram shows the relationships between members of this clan. More...

Species distribution

Tree controls


This tree shows the occurrence of the domains in this clan across different species. More...



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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