Role of fliC on biofilm formation, adhesion, and cell motility in Cronobacter malonaticus and regulation of luxS

作者：Ling, Na; Wang, Xin; Liu, Dengyu; Shen, Yizhong; Zhang, Danfeng; Ou, Dexin; Fan, Hongying; Wang, Juan; Ding, Yu; Zhang, Jumei; Wu, Qingping^*; Ye, Yingwang^*

来源：Food and Chemical Toxicology, 2021, 149: 111940.

DOI：10.1016/j.fct.2020.111940

• Cronobacter malonaticus
• luxS
• fliC
• Biofilm formation
• Adhesion
• Motility

Cronobacter malonaticus is one of the important foodborne pathogens causing infections mainly in adults. Biofilm formation, adhesion, and motility in Cronobacter have been documented, but the implying molecular mechanism has received little attention. Here, a comparison in biofilm formation, adhesion ability, and cell motility among wild type (WT), Delta luxS, and Delta fliC strains were analyzed using scanning electron microscope (SEM) and confocal laser scanning microscopy (CLSM). The thickest biofilm was formed by WT, followed by Delta luxS and Delta fliC. Furthermore, the deletion of fliC caused the loss of cell motility and the failure to flagella biosynthesis and mature biofilm formation. Besides, the adhesion abilities of Delta luxS and Delta fliC to biotic cells (LoVo and IEC-6) and abiotic surface (glass) were significantly decreased compared to WT, revealing that fliC might have an important role in the organism's invasion properties. We further demonstrated that the expression of negative regulator (flgM) of flagellin in Delta luxS was higher than that in WT, which indicated that luxS indirectly contributed to fliC expression. Our findings provided a novel perspective for precaution and control of C. malonaticus through intercepting fliC-mediated adhesion to biotic cells and abiotic surface.

• 单位
  广东省微生物研究所; 南方医科大学