Antagonistic activity and mechanism of SQ511 against .

is an important food-borne pathogen. The use of antibiotics is a serious threat to animal and human health, owing to the existence of resistant strains and drug residues. Lactic acid bacteria, as a new alternative to antibiotics, has attracted much attention. In this study, we investigated the antibacterial potential and underlying mechanism of SQ511 against ATCC13076. The results revealed that SQ511 significantly inhibited ATCC13076 growth or even caused death. Laser confocal microscopic imaging revealed that the cell-free supernatant (CFS) of SQ511 elevated the reactive oxygen species level and bacterial membrane depolarization in ATCC13076, leading to cell death. Furthermore, SQ511 CFS had severely deleterious effects on ATCC13076, causing membrane destruction and the release of cellular materials. In addition, SQ511 CFS significantly reduced the expression of virulence, motility, adhesion, and invasion genes in ATCC13076 ( < 0.05), and considerably inhibited motility and biofilm formation capacity ( < 0.05). Thus, antimicrobial compounds produced by SQ511 strongly inhibited growth, mobility, biofilm formation, membrane disruption, and reactive oxygen species generation, and regulated virulence-related gene expressions, presenting promising applications as a probiotic agent.