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158  structures 998  species 0  interactions 10289  sequences 427  architectures

Clan: Omega_toxin (CL0083)


Omega toxin-like Add an annotation

This clan contains a set of related small protein toxins and what appears to be the functionally distinct Albumin I domain. All members of this clan have a knottin-like fold. Additional information about this clan may be found from [1].

This clan contains 36 families and the total number of domains in the clan is 10289. The clan was built by RD Finn.

Literature references

  1. Gelly JC, Gracy J, Kaas Q, Le-Nguyen D, Heitz A, Chiche L; , Nucleic Acids Res 2004;32:D156-D159.: The KNOTTIN website and database: a new information system dedicated to the knottin scaffold. PUBMED:14681383 EPMC:14681383


This clan contains the following 36 member families:

ACI44 Agouti Albumin_I Albumin_I_a Antifungal_pept Antimicrobial25 Argos Atracotoxin CART CBM_1 Chi-conotoxin Conotoxin DUF5637 LEAP-2 Mu-conotoxin Omega-toxin Tachystatin_A Tachystatin_B Toxin_11 Toxin_12 Toxin_16 Toxin_18 Toxin_20 Toxin_21 Toxin_22 Toxin_23 Toxin_24 Toxin_27 Toxin_28 Toxin_30 Toxin_35 Toxin_7 Toxin_9 Tryp_inh UPF0506 Viral_cys_rich

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
CBM_1 (PF00734) 7945 (77.2%) View
CART (PF06373) 653 (6.3%) View
Agouti (PF05039) 577 (5.6%) View
LEAP-2 (PF07359) 331 (3.2%) View
UPF0506 (PF11703) 152 (1.5%) View
Antifungal_pept (PF11410) 140 (1.4%) View
Argos (PF11581) 106 (1.0%) View
Antimicrobial25 (PF16839) 98 (1.0%) View
Albumin_I_a (PF16720) 98 (1.0%) View
Albumin_I (PF08027) 48 (0.5%) View
Toxin_9 (PF02819) 47 (0.5%) View
Toxin_12 (PF07740) 27 (0.3%) View
DUF5637 (PF18687) 15 (0.1%) View
Toxin_18 (PF08087) 15 (0.1%) View
Viral_cys_rich (PF08008) 12 (0.1%) View
Conotoxin (PF02950) 10 (0.1%) View
Tryp_inh (PF17983) 6 (0.1%) View
Toxin_21 (PF08091) 2 (0.0%) View
Omega-toxin (PF06357) 2 (0.0%) View
Pfam family Num. domains Alignment
Mu-conotoxin (PF05374) 2 (0.0%) View
ACI44 (PF15270) 1 (0.0%) View
Tachystatin_A (PF11406) 1 (0.0%) View
Toxin_30 (PF08117) 1 (0.0%) View
Toxin_35 (PF10530) 0 (0.0%) View
Toxin_28 (PF08115) 0 (0.0%) View
Toxin_20 (PF08089) 0 (0.0%) View
Atracotoxin (PF05353) 0 (0.0%) View
Chi-conotoxin (PF16981) 0 (0.0%) View
Tachystatin_B (PF11478) 0 (0.0%) View
Toxin_27 (PF08099) 0 (0.0%) View
Toxin_24 (PF08094) 0 (0.0%) View
Toxin_23 (PF08093) 0 (0.0%) View
Toxin_22 (PF08092) 0 (0.0%) View
Toxin_16 (PF07945) 0 (0.0%) View
Toxin_11 (PF07473) 0 (0.0%) View
Toxin_7 (PF05980) 0 (0.0%) View
Total: 36 Total: 10289 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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