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277  structures 5885  species 0  interactions 38455  sequences 91  architectures

Clan: Plasmid-antitox (CL0136)


Plasmid toxin-antitoxin system Add an annotation

The families in this clan are plasmid encoded anti-toxins involved in plasmid maintenance. The plasmid encodes both a toxin and an antitoxin. Upon loss of the plasmid the antitoxin is inactivated more rapidly than the toxin. This allows the toxin to interact with its target thus killing the cell or impeding growth.

This clan contains 16 families and the total number of domains in the clan is 38455. The clan was built by J Mistry.

Literature references

  1. Anantharaman V, Aravind L; , Genome Biol 2003;4:R81.: New connections in the prokaryotic toxin-antitoxin network: relationship with the eukaryotic nonsense-mediated RNA decay system. PUBMED:14659018 EPMC:14659018
  2. Tian QB, Ohnishi M, Tabuchi A, Terawaki Y; , Biochem Biophys Res Commun 1996;220:280-284.: A new plasmid-encoded proteic killer gene system: cloning, sequencing, and analyzing hig locus of plasmid Rts1. PUBMED:8645296 EPMC:8645296
  3. Grady R, Hayes F; , Mol Microbiol 2003;47:1419-1432.: Axe-Txe, a broad-spectrum proteic toxin-antitoxin system specified by a multidrug-resistant, clinical isolate of Enterococcus faecium. PUBMED:12603745 EPMC:12603745


This clan contains the following 16 member families:

BrnT_toxin DUF2281 DUF4258 Gp49 HigB-like_toxin MqsR_toxin ParE-like_toxin ParE_toxin PHD_like PhdYeFM_antitox REGB_T4 RelE Toxin_YhaV TrmO_C YafQ_toxin YoeB_toxin

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
ParE_toxin (PF05016) 11625 (30.2%) View
PhdYeFM_antitox (PF02604) 10568 (27.5%) View
Gp49 (PF05973) 3402 (8.8%) View
YoeB_toxin (PF06769) 2427 (6.3%) View
HigB-like_toxin (PF05015) 2252 (5.9%) View
BrnT_toxin (PF04365) 2202 (5.7%) View
YafQ_toxin (PF15738) 1231 (3.2%) View
RelE (PF06296) 1120 (2.9%) View
TrmO_C (PF18389) 1056 (2.7%) View
DUF4258 (PF14076) 799 (2.1%) View
DUF2281 (PF10047) 671 (1.7%) View
Toxin_YhaV (PF11663) 380 (1.0%) View
ParE-like_toxin (PF15781) 319 (0.8%) View
MqsR_toxin (PF15723) 220 (0.6%) View
PHD_like (PF12910) 128 (0.3%) View
REGB_T4 (PF10715) 55 (0.1%) View
Total: 16 Total: 38455 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...