Bacteriocin CM175, a new high molecular weight and phage associated protein produced by Pediococcus pentosaceus CM175

Bacteriocins are proteins with antimicrobial capacity produced by different bacteria. Developing bacteriocin-based technologies could be an effective strategy to address current problems in the pharmaceutical and food industries, including limited therapeutic options against superbug infections, foodborne diseases, and food spoilage microorganisms. The lactic acid bacteria Pediococcus pentosaceus are known producers of bacteriocins. Particularly, Ped. pentosaceus strain CM175 has been reported to produce an uncharacterized bacteriocin-like inhibitory substance (BLIS) with an interesting antibacterial spectrum against Gram-positive and -negative pathogenic bacteria. The objective of the present study was to explore whether the BLIS produced by CM175 contains at least one bacteriocin, and identify it. Our results showed that the CM175 strain produced a non-previously characterized antimicrobial protein of 49 kDa identified by mass spectrometry as a phage-related protein, named bacteriocin CM175. Through fluorescence and transmission electron microscopies, it was demonstrated that bacteriocin CM175 damages the cell membrane integrity of Listeria monocytogenes through a non-lytic mechanism. Bacteriocin CM175 is the first high molecular weight and phage protein-like bacteriocin reported in Ped. pentosaceus. The results of this study open the possibility of exploring various applications directly related to the antimicrobial potential of bacteriocin CM175, including the development of antibiotics, and disinfectants.