Peptidase E (PEPE)

PepE is an N-terminal Asp-specific dipeptidase. PepE is not inhibited by any of the classical peptidase inhibitors, and its amino acid sequence does not place it in any of the known peptidase structural classes. A comparison of the amino acid sequence of PepE with a number of related sequences has allowed to define the amino acid residues that are strongly conserved in this family. One of the most distantly related relatives in Escherichia coli and have shown that it is indeed an Asp-specific dipeptidase with properties very similar to those of serovar Typhimurium PepE. The sequence comparison suggests that PepE is a serine hydrolase. PepE is the prototype of a new family of serine peptidases. The phylogenetic distribution of the family is unusual, since representatives are found in eubacteria, an insect , and a vertebrate but not in the Archaea or in any of the other eukaryotes for which genome sequences are available.