SMART: Pfam domain TcdB

TcdB_N

PFAM accession number:	PF12918
Interpro abstract (IPR024772):	This entry represents a short helical bundle domain found associated with the catalytic domain of TcdA and TcdB [ (PUBMED:16054646) ]. It is also found in some other toxins. The function of this domain is unknown, but it may be involved in substrate recognition. 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) ].

PFAM accession number:

PF12918

Interpro abstract (IPR024772):

This entry represents a short helical bundle domain found associated with the catalytic domain of TcdA and TcdB [ (PUBMED:16054646) ]. It is also found in some other toxins. The function of this domain is unknown, but it may be involved in substrate recognition.

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 is a PFAM domain. For full annotation and more information, please see the PFAM entry TcdB_N