Catalyzes the removal of dipeptides from the N-terminus of oligopeptides. Most efficiently cleaves the synthetic substrate Met-Leu-methylcoumaryl-7-amide (Met-Leu-MCA), and slowly hydrolyzes Leu-Gln-, Lys-Ala-, Leu-Arg, and Ala-Asn-MCA. Is likely involved in amino acid metabolism and bacterial growth/survival of asaccharolytic P.endodontalis, that utilizes amino acids from extracellular proteinaceous nutrients as energy and carbon sources. The C-terminal Lys-rich domain (711-818) is dispensable for the proteolytic activity. Belongs to the peptidase S46 family.