Purification, partial amino acid sequence and mode of action of pediocin PD-1, a bacteriocin produced by Pediococcus damnosus NCFB 1832.

Pediocin PD-1 is a ribosomally synthesized antimicrobial peptide produced by Pediococcus damnosus NCFB1832. It inhibits the growth of several food spoilage bacteria, including malolactic bacteria isolated from wine. Pediocin PD-1 is 2866.87+/-0.4 Da in size, has an isoelectric point (pI) of ca. 9.0 and, on amino acid composition, has partial homology to the lantibiotic plantaricin C. The highest activity of pediocin PD-1 against cells of Oenococcus oeni was observed at an external pH of 5.0 and at 25 degrees C. The primary mode of action of pediocin PD-1 is most probably due to pore formation, as indicated by the efflux of K+ from metabolically active cells of O. oeni. In the presence of 10 mM gadolinium (Gd3+), pediocin PD-1 did not affect cells of O. oeni. This suggests that the mode of action of pediocin PD-1 relies on a net negatively charged cell surface. In comparison to nisin, pediocin PD-1 is less active against non-growing cells of O. oeni.