The Effect of Licochalcone A on the Expression Levels of Salmonella Typhimurium Genes Involved in Quorum Sensing

Background: Quorum sensing is a microbial cell-to-cell communication process which bacteria produce and release extracellular messenger molecules called auto inducers. Studies have shown that the use of antibiotics and medicinal plants at suboptimal concentrations can interfere with the translation of QS genes. The aim of this study was to evaluation the impact of sub-inhibitory concentrations of Licochalcone A (LAA) on the luxS and sdiA genes expression. Methods: This analytical study was performed using standard strains of S. Typhimurium (RITCC1730) and 23 clinical S. Typhimurium isolates from poultry flocks, were incubated at 37°C for 45 min in the presence of LAA. The expression of the sdiA and luxS genes was then assessed using the real-time PCR protocol and SYBR Green Master Mix. The data analysis was carried out using the ∆∆CT method. Results: Quantitative RT-PCR analysis on total RNA demonstrated significant less expression of sdiA and luxS genes in 23 treated S. Typhimurium isolates with LAA in comparison to non-treated ones of the same strain. Conclusion: The results indicate that sMICs of LAA as anti-quorum sensing herbal agents with natural origin can be used to control the expression of virulence genes in S. Typhimurium.

کلیدواژه ها:

Licochalcone A ، luxS gene ، sdiA gene ، qRT-PCR ، S. Typhimurium