Integrative physiological, proteomic, and functional analyses reveal the antibacterial mechanism of lauroyl arginate ethyl against Salmonella Enteritidis.

Salmonella Enteritidis, a major foodborne bacterial pathogen commonly linked to poultry products, necessitates effective control measures. This study investigated the antibacterial activity and underlying mechanism of lauroyl arginate ethyl (LAE) against S. Enteritidis by integrating physiological, proteomic, and functional analyses. LAE exhibited potent concentration- and time-dependent antibacterial effects in vitro. In chicken meat, LAE at 0.2 and 0.4 mg/mL completely inactivated S. Enteritidis within 30 min. Scanning electron microscopy and selective recovery assays demonstrated that LAE caused severe envelope damage and morphological deformation. Moreover, LAE markedly reduced swimming and swarming motility while promoting cell auto-aggregation, indicating altered surface-associated behaviors. TMT-based proteomic analysis identified 1041 differentially expressed proteins (454 up-regulated and 587 down-regulated) after LAE treatment. These proteins were involved in key pathways such as the TCA cycle, two-component systems, bacterial invasion of epithelial cells, ribosome biogenesis, and envelope homeostasis. Functional analysis revealed that deletion of efflux-functional AcrD or envelope-stabilizing YbgC increased bacterial susceptibility to LAE, which established both proteins as critical determinants for LAE antibacterial activity. Collectively, LAE combats S. Enteritidis through interference with multiple interconnected pathways, highlighting its potential as a novel and effective intervention for Salmonella contamination.