Partial characterization of heat-stable, antilisterial and cell lytic bacteriocin of Pediococcus pentosaceus CFR SIII isolated from a vegetable source

Heat-stable, antilisterial and cell lytic bacteriocinproducing
Pediococcus pentosaceus CFR SIII isolated from
a vegetable source (cucumber) was partially characterized.
The isolate was identified by microbiological methods and
16S rRNA gene sequences. The bacteriocin produced by this
isolate, designated as PP SIII, was active against several
Gram-positive and Gram-negative food-borne pathogens and
food spoilage lactic acid bacteria. The apparent molecular
mass of the partially purified bacteriocin was found to be
∼5 kDa by Tricine SDS-PAGE. It was stable at pH 3–5 and
at 121°C for 15 min and inactivated by various proteases.
The mode of action of the bacteriocin through FTIR analysis
and glycolytic activity assay revealed cell lytic activity
against the indicator Pediococcus acidilactici B1153 by
complete cell lysis, depletion of intracellular solute and
disruption of pH gradient. The study envisages the potentiality
of the isolate in vegetable preservation or as an adjunct culture
in various cheese varieties to avoid chemical preservatives.