There are several reports on the detection of Listeria monocytogenes in Iran, which has been identified as a major public health problem. In addition, due to drug resistance and strong biofilm formation of this pathogen, new approaches such as using probiotics are needed to combat this bacterium. The aim of this study was to investigate the effect of spore-forming probiotics on the expression of virulence genes hly, plc, inlA, and invasion of L. monocytogenes. Spore-forming probiotics were co-cultured with L. monocytogenes at different time points and following cell count, the expression level of virulence genes of L. monocytogenes was assessed by real-time PCR. To investigate the effect of the isolated strains on the invasiveness of L. monocytogenes at different time points, HT-29 cell line was used. Sporulated probiotics reduced the growth of L. monocytogenes in broth medium at different time periods. The number of L. monocytogenes co-cultured with Bacillus laterosporus decreased by 1, 3, 3, and 6 log at 2, 4, 8 and 24 h after treatment, respectively. In addition, the expression of virulence genes was decreased at different time points and the expression of hly and plcA genes was more affected. The invasion rate of L. monocytogenes on HT-29 cells was decreased by 1 to 6 log at different time points. Both probiotic strains inhibited bacterial growth at different time points; however, more sensitive methods should be established for an accurate assessment.

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芽孢杆菌侧孢芽孢杆菌和巨大芽孢杆菌对单核细胞增生李斯特菌的抗菌作用

有几份关于在伊朗检测到单核细胞增生李斯特菌的报告，该病已被确定为一个主要的公共卫生问题。此外，由于这种病原体的耐药性和强大的生物膜形成，需要使用益生菌等新方法来对抗这种细菌。本研究的目的是研究产孢益生菌对毒力基因 hly、plc、inlA 的表达和单核细胞增生李斯特氏菌侵袭的影响。在不同时间点将产孢益生菌与单核细胞增生李斯特菌共培养，并在细胞计数后，通过实时荧光定量 PCR 评估单核细胞增生李斯特氏菌毒力基因的表达水平。为了研究分离菌株在不同时间点对单核细胞增生李斯特氏菌侵袭性的影响，使用了 HT-29 细胞系。孢子化益生菌降低了 L. 的生长。不同时间段肉汤培养基中的单核细胞增生症。在处理后 2、4、8 和 24 小时，与侧孢芽孢杆菌共培养的单核细胞增生李斯特菌的数量分别减少了 1、3、3 和 6 个 log。此外，毒力基因在不同时间点的表达下降，hly和plcA基因的表达受到的影响更大。单核细胞增生李斯特菌对HT-29细胞的侵袭率在不同时间点降低了1～6个log。两种益生菌菌株在不同时间点抑制细菌生长；然而，应该建立更灵敏的方法来进行准确的评估。毒力基因在不同时间点表达降低，对hly和plcA基因表达影响较大。单核细胞增生李斯特菌对HT-29细胞的侵袭率在不同时间点降低了1～6个log。两种益生菌菌株在不同时间点抑制细菌生长；然而，应该建立更灵敏的方法来进行准确的评估。毒力基因在不同时间点表达降低，对hly和plcA基因表达影响较大。单核细胞增生李斯特菌对HT-29细胞的侵袭率在不同时间点降低了1～6个log。两种益生菌菌株在不同时间点抑制细菌生长；然而，应该建立更灵敏的方法来进行准确的评估。