Prepilin peptidase (EC 3.4.23.43) is an enzyme found in Type IV filament systems responsible for the maturation of the pilin. This enzyme catalyses the following chemical reaction
- Typically cleaves a -Gly-Phe- bond to release an N-terminal, basic peptide of 5-8 residues from type IV prepilin, and then N-methylates the new N-terminal amino group, the methyl donor being S-adenosyl-L-methionine.
This enzyme is present on the surface of many species of bacteria. All known enzymes with this activity are of the MEROPS family A24.