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881  structures 8306  species 0  interactions 267333  sequences 19548  architectures

Clan: PAS_Fold (CL0183)


PAS domain clan Add an annotation

This clan contains PAS domains that are found in a wide variety of bacterial signaling proteins.

This clan contains 17 families and the total number of domains in the clan is 267333. The clan was built by A Bateman.

Literature references

  1. Zhulin IB, Taylor BL, Dixon R; , Trends Biochem Sci 1997;22:331-333.: PAS domain S-boxes in archaea, bacteria and sensors for oxygen and redox. PUBMED:9301332 EPMC:9301332
  2. Borgstahl GE, Williams DR, Getzoff ED; , Biochemistry 1995;34:6278-6287.: 1.4 A structure of photoactive yellow protein, a cytosolic photoreceptor: unusual fold, active site, and chromophore. PUBMED:7756254 EPMC:7756254
  3. Ponting CP, Aravind L; , Curr Biol 1997;7:674-677.: PAS: a multifunctional domain family comes to light. PUBMED:9382818 EPMC:9382818
  4. Hefti MH, Francoijs KJ, de Vries SC, Dixon R, Vervoort J; , Eur J Biochem 2004;271:1198-1208.: The PAS fold: a redefination of the PAS domain based upon structural prediction. PUBMED:15009198 EPMC:15009198


This clan contains the following 17 member families:

AbfS_sensor CpxA_peri DUF5593 MEKHLA MLTR_LBD PAS PAS_10 PAS_11 PAS_12 PAS_2 PAS_3 PAS_4 PAS_5 PAS_6 PAS_7 PAS_8 PAS_9

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
PAS (PF00989) 58225 (21.8%) View
PAS_4 (PF08448) 58162 (21.8%) View
PAS_3 (PF08447) 57710 (21.6%) View
PAS_9 (PF13426) 38837 (14.5%) View
PAS_8 (PF13188) 16764 (6.3%) View
MLTR_LBD (PF17765) 10563 (4.0%) View
PAS_7 (PF12860) 8171 (3.1%) View
PAS_11 (PF14598) 7663 (2.9%) View
PAS_2 (PF08446) 3281 (1.2%) View
PAS_10 (PF13596) 2777 (1.0%) View
MEKHLA (PF08670) 1797 (0.7%) View
PAS_6 (PF08348) 1657 (0.6%) View
PAS_5 (PF07310) 1337 (0.5%) View
CpxA_peri (PF16527) 194 (0.1%) View
DUF5593 (PF18007) 157 (0.1%) View
AbfS_sensor (PF18225) 23 (0.0%) View
PAS_12 (PF18095) 15 (0.0%) View
Total: 17 Total: 267333 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.

Loading structure mapping...