AUTHOR=Cheng Chuansong , Yan Xiaotong , Liu Binxiong , Jiang Tao , Zhou Ziwen , Guo Fengting , Zhang Qianwen , Li Changcheng , Fang Ting 

TITLE=SdiA Enhanced the Drug Resistance of Cronobacter sakazakii and Suppressed Its Motility, Adhesion and Biofilm Formation

JOURNAL=Frontiers in Microbiology

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.901912

DOI=10.3389/fmicb.2022.901912

ISSN=1664-302X

ABSTRACT=<p><italic>Cronobacter sakazakii</italic> is a common foodborne pathogen, and the mortality rate of its infection is as high as 40–80%. SdiA acts as a quorum sensing regulator in many foodborne pathogens, but its role in <italic>C. sakazakii</italic> remains unclear. Here, we further determined the effect of the <italic>sdiA</italic> gene in <italic>C. sakazakii</italic> pathogenicity. The <italic>SdiA</italic> gene in <italic>C. sakazakii</italic> was knocked out by gene editing technology, and the biological characteristics of the Δ<italic>sdiA</italic> mutant of <italic>C. sakazakii</italic> were studied, followed by transcriptome analysis to elucidate its effects. The results suggested that <italic>SdiA</italic> gene enhanced the drug resistance of <italic>C. sakazakii</italic> but diminished its motility, adhesion and biofilm formation ability and had no effect on its growth. Transcriptome analysis showed that the Δ<italic>sdiA</italic> upregulated the expression levels of D-galactose operon genes (including <italic>dgoR</italic>, <italic>dgoK</italic>, <italic>dgoA</italic>, <italic>dgoD</italic> and <italic>dgoT</italic>) and flagella-related genes (<italic>FliA</italic> and <italic>FliC</italic>) in <italic>C. sakazakii</italic> and downregulated the expression levels of related genes in the type VI secretion system (<italic>VasK</italic> gene was downregulated by 1.53-fold) and ABC transport system (downregulated by 1.5-fold), indicating that <italic>SdiA</italic> gene was related to the physiological metabolism of <italic>C. sakazakii</italic>. The results were useful for clarifying the pathogenic mechanism of <italic>C. sakazakii</italic> and provide a theoretical basis for controlling bacterial infection.</p>