A Regulatory SRNA Rli43 Is Involved in the Modulation of Biofilm Formation and Virulence in Listeria monocytogenes

作者：Lixia Wang, Chunhui Ji, Xianzhu Xia, Xuepeng Cai, Qingling Meng, Jun Qiao · 发表于：Pathogens · 年份：2022 · DOI：10.3390/pathogens11101137 · 被引用次数：9 · 研究领域：Molecular Biology Techniques and Applications、Salmonella and Campylobacter epidemiology、Listeria monocytogenes in Food Safety

Small RNAs (sRNAs) are a kind of regulatory molecule that can modulate gene expression at the post-transcriptional level, thereby involving alteration of the physiological characteristics of bacteria. However, the regulatory roles and mechanisms of most sRNAs remain unknown in Listeria monocytogenes(L. monocytogenes). To explore the regulatory roles of sRNA Rli43 in L. monocytogenes, the rli43 gene deletion strain LM-Δrli43 and complementation strain LM-Δrli43-rli43 were constructed to investigate the effects of Rli43 on responses to environmental stress, biofilm formation, and virulence, respectively. Additionally, Rli43-regulated target genes were identified using bioinformatic analysis tools and a bacterial dual plasmid reporter system based on E. coli. The results showed that the intracellular expression level of the rli43 gene was significantly upregulated compared with those under extracellular conditions. Compared with the parental and complementation strains, the environmental adaptation, motility, biofilm formation, adhesion, invasion, and intracellular survival of LM-Δrli43 were significantly reduced, respectively, whereas the LD50 of LM-Δrli43 was significantly elevated in BALB/c mice. Furthermore, the bacterial loads and pathological damages were alleviated, suggesting that sRNA Rli43 was involved in the modulation of the virulence of L. monocytogenes. It was confirmed that Rli43 may complementarily pair with the 5′-UTR (−47–−55) of HtrA mRNA, thereby regulating t...