Portal de Periódicos da CAPES

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

2010; Elsevier BV; Volume: 22; Issue: 6 Linguagem: Inglês

10.1016/j.foodcont.2010.11.029

1873-7129

Daniel P. Abrams, Joana Barbosa, Helena Albano, Joana Silva, Paul Gibbs, Paula Teixeira,

Protein Hydrolysis and Bioactive Peptides

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.