Summary: TcdA/TcdB pore forming domain
TcdA/TcdB pore forming domain Provide feedback
This family represents the most conserved region within the C. difficile Toxin A and Toxin B pore forming region.
Barth H, Pfeifer G, Hofmann F, Maier E, Benz R, Aktories K;, J Biol Chem. 2001;276:10670-10676.: Low pH-induced formation of ion channels by clostridium difficile toxin B in target cells. PUBMED:11152463 EPMC:11152463
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This tab holds annotation information from the InterPro database.
InterPro entry IPR024769
Toxins A (TcdA) and B (TcdB) of Clostridium difficile belong to the family of clostridial glucosylating toxins. These toxins glucosylate small GTPases of Rho and Ras families, inhibiting the signalling and regulatory functions of these switch proteins. After receptor-binding, the toxins are endocytosed to reach acidic endosomal compartments from where the toxins are translocated into the cytosol [PUBMED:20498856].
TcdB has been shown to consist of a N-terminal glucosyltransferase domain (GTD), responsible for the biological effects of the toxin, a cysteine protease domain (CPD), responsible for autocatalytic cleavage, a hydrophobic region (HR), which has been suggested to be involved in toxin translocation, and a C-terminal repetitive domain involved in receptor binding. The pore-forming region of toxin B has been described to be in a region in the middle of the protein, within amino acid residues 830 and 990 [PUBMED:21231971].
This entry represents the pore forming domain of TcdA and TcdB. It is also found in other toxins.
The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.
|Biological process||pathogenesis (GO:0009405)|
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Curation and family details
|Seed source:||Bateman A|
|Number in seed:||18|
|Number in full:||84|
|Average length of the domain:||620.80 aa|
|Average identity of full alignment:||33 %|
|Average coverage of the sequence by the domain:||30.49 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 23193494 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||2|
|Download:||download the raw HMM for this family|
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