Characterization of bacPPK34 a bacteriocin produced by Pediococcus pentosaceus strain K34 isolated from “Alheira”

• Published in: Food control Vol. 22; no. 6; pp. 940 - 946
• Main Authors: Abrams, Daniel, Barbosa, Joana, Albano, Helena, Silva, Joana, Gibbs, Paul A., Teixeira, Paula
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-06-2011
• Subjects: Antimicrobial activity; Bacteria; Fermented meat sausage; Pediocin-like bacteriocins; Pediococcus pentosaceus; Pediocin-like bacteriocins; Fermented meat sausage; Pediococcus pentosaceus
• ISSN: 0956-7135; 1873-7129
• DOI: 10.1016/j.foodcont.2010.11.029

Different lactic acid bacteria were isolated during different stages in the production of “Alheiras”, a traditionally fermented sausage produced in the north of Portugal, between 2005 and 2007, in a total of 484 isolates. One of 484 isolates (K34) produced a bacteriocin, designated as bacPPK34, and was identified as a strain of Pediococcus pentosaceus by 16S rRNA sequencing. The highest bacteriocin production was noted at late log/early stationary phase after 15–18 h of growth in MRS broth at 37 °C (3200 AU/ml) against Enterococcus faecalis ATCC 29212 and 12800 AU/ml against Listeria monocytogenes (L1, L2, L3). bacPPK34 was between 2.5 kDa and 6.2 kDa in size, as determined by tricine-SDS-PAGE. Complete inactivation or significant reduction in antimicrobial activity was observed after treatment of cell-free supernatants with proteinase K, pepsin and trypsin. No change in activity was recorded when treated with catalase. The bacteriocin was resistant to treatments with lipase and detergents Triton X-100, Tween 20, SDS, NaCl, urea and EDTA. Furthermore, the bacteriocin remained active after 2 h at pH 2–12 and temperature treatments at 60, 80, 100 °C, 1 month of storage at −20 and 4 °C and 20 min at 121 °C. Addition of bacPPK34 to a mid-log culture of L. monocytogenes and E. faecalis ATCC 29212 inhibited growth. The bacteriocin did not adhere to the surface of the producer cells.