Plays a role in type II pseudopili formation by proteolytically removing the leader sequence from substrate proteins and subsequently monomethylating the alpha-amino group of the newly exposed N-terminal phenylalanine. Substrates include proteins required for biogenesis of the type II general secretory apparatus. 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. Zinc is required for the N-terminal methylation of the mature pilin, but not for signal peptide cleavage. By several proteins including Spo0A, Spo0H, Sin, AbrB, DegS, DegU, ComA, ComB and ComK. Belongs to the peptidase A24 family.