Genetic characterization of pepP, which encodes an aminopeptidase P whose deficiency does not affect Lactococcus lactis growth in milk, unlike deficiency of the X-prolyl dipeptidyl aminopeptidase.

We sequenced the pepP gene of Lactococcus lactis, which encodes an aminopeptidase P (PepP), and demonstrated that the X-prolyl dipeptidyl aminopeptidase PepX plays a more important role than PepP in nitrogen nutrition. PepP shares homology with methionine aminopeptidases and could play a role in the maturation of nascent proteins.