The members of this family are are sequences that are similar to the N-terminal half of the ShET2 enterotoxin produced by Shigella flexneri and Escherichia coli. This protein was found to confer toxigenicity in the Ussing chamber, and the N-terminal region was found to be important for the protein's enterotoxic effect. It is thought to be a hydrophobic protein that forms inclusion bodies within the bacterial cell, and may be secreted by the Mxi system. Most members of this family are annotated as putative enterotoxins, but one member is a regulator of acetyl CoA synthetase, and another two members are annotated as ankyrin-like regulatory proteins and contain Ank repeats (pfam00023).
Jiyao W et al.(2023). "The conserved domain database in 2023.",