Like all macroorganisms, plants have to control bacterial biofilm formation on their surfaces. On the other hand, biofilms are highly tolerant against antimicrobial agents and other stresses. Consequently, biofilms are also involved in human chronic infectious diseases, which generates a strong demand for anti‐biofilm agents. Therefore, we systematically explored major plant flavonoids as putative anti‐biofilm agents using different types of biofilms produced by Gram‐negative and Gram‐positive bacteria. In Escherichia coli macrocolony biofilms, the flavone luteolin and the flavonols myricetin, morin and quercetin were found to strongly reduce the extracellular matrix. These agents directly inhibit the assembly of amyloid curli fibres by driving CsgA subunits into an off‐pathway leading to SDS‐insoluble oligomers. In addition, they can interfere with cellulose production by still unknown mechanisms. Submerged biofilm formation, however, is hardly affected. Moreover, the same flavonoids tend to stimulate macrocolony and submerged biofilm formation by Pseudomonas aeruginosa. For Bacillus subtilis, the flavonone naringenin and the chalcone phloretin were found to inhibit growth. Thus, plant flavonoids are not general anti‐biofilm compounds but show species‐specific effects. However, based on their strong and direct anti‐amyloidogenic activities, distinct plant flavonoids may provide an attractive strategy to specifically combat amyloid‐based biofilms of some relevant pathogens.

中文翻译：

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常见的植物类黄酮会阻止淀粉样蛋白卷曲纤维的组装，并会干扰细菌生物膜的形成。

像所有大生物一样，植物必须控制其表面细菌生物膜的形成。另一方面，生物膜对抗菌剂和其他压力具有高度的耐受性。因此，生物膜也参与人类慢性传染病，这引起了对抗生物膜剂的强烈需求。因此，我们使用革兰氏阴性菌和革兰氏阳性菌产生的不同类型的生物膜系统地研究了主要植物类黄酮作为推定的抗生物膜剂。在大肠杆菌中发现大殖民地生物膜，黄酮木犀草素和黄酮醇杨梅素，香豆素和槲皮素可强烈还原细胞外基质。这些药物通过驱动CsgA亚基进入导致SDS不溶性低聚物的偏路而直接抑制淀粉样蛋白卷曲纤维的组装。此外，它们还可以通过未知的机制干扰纤维素的生产。但是，浸没生物膜的形成几乎不受影响。而且，相同的类黄酮倾向于刺激铜绿假单胞菌（Pseudomonas aeruginosa）的大菌落和淹没的生物膜形成。对于枯草芽孢杆菌，发现黄酮酮柚皮素和查尔酮伞菌素抑制生长。因此，植物类黄酮不是一般的抗生物膜化合物，而是具有物种特异性的作用。但是，基于它们强大而直接的抗淀粉样蛋白生成活性，不同的植物类黄酮可能提供了一种有吸引力的策略来专门对抗某些相关病原体的基于淀粉样蛋白的生物膜。