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1314  structures 4920  species 0  interactions 34124  sequences 1082  architectures

Clan: Sialidase (CL0434)


Sialidase superfamily Add an annotation

This superfamily includes sialidases enzymes. Several viruses use sialic acid as a cell surface receptor for host invasion. These viruses then have cell surface neuraminidase enzymes to cleave sialic acid from cell surface proteins allowing them to leave the host cell after replication. This superfamily are composed of six beta-sheets that form a six-fold beta-propeller structure. Many members of this superfamily contain BNR sequence motifs Pfam:PF02012.

This clan contains 16 families and the total number of domains in the clan is 34124. The clan was built by A Bateman.

Literature references

  1. Taylor G;, Curr Opin Struct Biol. 1996;6:830-837.: Sialidases: structures, biological significance and therapeutic potential. PUBMED:8994884 EPMC:8994884


This clan contains the following 16 member families:

BNR BNR_2 BNR_3 BNR_4 BNR_6 End_beta_barrel End_beta_propel Fungal_lectin HN Mcl1_mid Neur Neuraminidase OLF Phytase PSII_BNR Sortilin-Vps10

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
OLF (PF02191) 8385 (24.6%) View
Sortilin-Vps10 (PF15902) 7799 (22.9%) View
BNR_2 (PF13088) 6255 (18.3%) View
PSII_BNR (PF14870) 2827 (8.3%) View
BNR_3 (PF13859) 2104 (6.2%) View
Mcl1_mid (PF12341) 1837 (5.4%) View
Phytase (PF02333) 1393 (4.1%) View
BNR_4 (PF15892) 1237 (3.6%) View
BNR (PF02012) 1223 (3.6%) View
Fungal_lectin (PF07938) 455 (1.3%) View
Neuraminidase (PF18413) 344 (1.0%) View
BNR_6 (PF15899) 122 (0.4%) View
HN (PF00423) 69 (0.2%) View
Neur (PF00064) 37 (0.1%) View
End_beta_propel (PF12217) 19 (0.1%) View
End_beta_barrel (PF12195) 18 (0.1%) View
Total: 16 Total: 34124 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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