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513  structures 8201  species 0  interactions 27971  sequences 253  architectures

Clan: SHS2 (CL0319)


SHS2 domain Add an annotation

SHS2 is a novel domain with a simple fold containing a core of 3 strands, forming a curved sheet, and a single helix in a strand-helix-strand-strand (SHS2) configuration [1]. SHS2 is found in the bacterial cell division ATPase FtsA, the archaeo-eukaryotic RNA polymerase subunit Rpb7p, the GyrI superfamily, and the uncharacterized MTH1598/Tm1083-like proteins [1]. The fold exists as single copy versions in FtsA (where it is inserted into the RNAseH fold), Rbp7p and Dodecin [1]. It is found as a diad in the GyrI superfamily. In MTH1598/Tm1083-like proteins two copies of SHS2 are found with one inserted into another [1]. The single-copy versions in FtsA and Rbp7 mediate protein–protein interactions, while the one in Dodecin is a small molecule binding domain. The GyrI also binds small molecule, while the MTH1598 is predicted to be enzymatic [1].

This clan contains 9 families and the total number of domains in the clan is 27971. The clan was built by A Bateman and V Anantharaman.

Literature references

  1. Anantharaman V, Aravind L;, Proteins. 2004;56:795-807.: The SHS2 module is a common structural theme in functionally diverse protein groups, like Rpb7p, FtsA, GyrI, and MTH1598/TM1083 superfamilies. PUBMED:15281131 EPMC:15281131
  2. Dias JS, Macedo AL, Ferreira GC, Peterson FC, Volkman BF, Goodfellow BJ; , J Biol Chem. 2006;281:31553-31561.: The first structure from the SOUL/HBP family of heme-binding proteins, murine P22HBP. PUBMED:16905545 EPMC:16905545
  3. Canaves JM; , Proteins. 2004;56:19-27.: Predicted role for the archease protein family based on structural and sequence analysis of TM1083 and MTH1598, two proteins structurally characterized through structural genomics efforts. PUBMED:15162483 EPMC:15162483
  4. Bieger B, Essen LO, Oesterhelt D;, Structure. 2003;11:375-385.: Crystal structure of halophilic dodecin: a novel, dodecameric flavin binding protein from Halobacterium salinarum. PUBMED:12679016 EPMC:12679016


This clan contains the following 9 member families:

Archease Cass2 Dodecin GyrI-like LPP20 SHS2_FTSA SHS2_Rpb7-N SOUL Tipalpha

External database links

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
GyrI-like (PF06445) 7887 (28.2%) View
SHS2_FTSA (PF02491) 5252 (18.8%) View
SOUL (PF04832) 3944 (14.1%) View
SHS2_Rpb7-N (PF03876) 3697 (13.2%) View
Cass2 (PF14526) 2491 (8.9%) View
Dodecin (PF07311) 2463 (8.8%) View
Archease (PF01951) 1527 (5.5%) View
LPP20 (PF02169) 704 (2.5%) View
Tipalpha (PF16753) 6 (0.0%) View
Total: 9 Total: 27971 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


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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