PROSITE documentation PDOC00246

Heat-stable enterotoxins signature

Prokaryotic heat-stable enterotoxins [1] are responsible for acute diarrhea. The active toxin is a short peptide of around twenty residues which contains six cysteines involved in three disulfide bonds, as shown in the following schematic representation:

                                +-------+
                             +--|----+  |
                             |  |    |  |
                          xxCCxxCCxxxCxxCxx
                            |    |
                            +----+

'C': conserved cysteine involved in a disulfide bond.

We have taken the pattern of cysteines, along with three conserved residues, as a signature pattern for this group of proteins.