PDF(Pubmed)
Abstract：
Probiotic biofilms have been beneficial in the fight against infections, restoring the equilibrium of the host\'s gut microbiota, and enhancing host health. They are considered a novel strategy for probiotic gut colonization. In this case, we evaluated the effects of various active substances from traditional Chinese medicine on Escherichia coli Nissle 1917 (EcN) to determine if they promote biofilm formation. It was shown that 8-64 μg/mL of oleanolic acid increased the development of EcN biofilm. Additionally, we observed that oleanolic acid can effectively suppress biofilm formation in pathogenic bacteria such as Salmonella and Staphylococcus aureus. Next, we assessed the amount of EcN extracellular polysaccharides, the number of live bacteria, their metabolic activity, the hydrophobicity of their surface, and the shape of their biofilms using laser confocal microscopy. Through transcriptome analysis, a total of 349 differentially expressed genes were identified, comprising 134 upregulated and 215 downregulated genes. GO functional enrichment analysis and KEGG pathway enrichment analysis revealed that oleanolic acid functions are through the regulation of bacterial motility, the iron absorption system, the two-component system, and adhesion pathways. These findings suggest that the main effects of oleanolic acid are to prevent bacterial motility, increase initial adhesion, and encourage the development of EcN biofilms. In addition, oleanolic acid interacts with iron absorption to cooperatively control the production of EcN biofilms within an optimal concentration range. Taking these results together, this study suggests that oleanolic acid may enhance probiotic biofilm formation in the intestines, presenting new avenues for probiotic product development.
摘要：
益生菌生物膜在对抗感染方面是有益的，恢复宿主肠道微生物群的平衡，增强宿主健康。它们被认为是益生菌肠道定植的新策略。在这种情况下,我们评估了各种中药活性物质对大肠杆菌Nissle1917（EcN）的影响，以确定它们是否促进生物膜形成。结果表明，8-64μg/mL的齐墩果酸增加了EcN生物膜的发育。此外,我们观察到齐墩果酸能有效抑制沙门氏菌和金黄色葡萄球菌等病原菌的生物膜形成。接下来,我们评估了EcN胞外多糖的量，活细菌的数量，它们的代谢活动，它们表面的疏水性，以及使用激光共聚焦显微镜检查它们的生物膜的形状。通过转录组分析,共鉴定出349个差异表达基因，包括134个上调的基因和215个下调的基因。GO功能富集分析和KEGG途径富集分析揭示齐墩果酸功能是通过调节细菌运动,铁吸收系统，双组分系统，和粘连途径。这些发现表明齐墩果酸的主要作用是防止细菌运动，增加初始附着力，并鼓励EcN生物膜的发展。此外,齐墩果酸与铁吸收相互作用以在最佳浓度范围内协同控制EcN生物膜的产生。把这些结果放在一起，这项研究表明齐墩果酸可能会增强肠道中益生菌生物膜的形成，为益生菌产品开发提供了新的途径。
