The Regulatory Role of EvfG Through Coordinated Control of Flagellar Biosynthesis and Energy Metabolism in Porcine Extraintestinal Pathogenic (ExPEC).

In this study, we found that the deletion of the gene in the type VI secretion system (T6SS) gene cluster significantly affected the motility of porcine extraintestinal pathogenic (ExPEC) strain PCN033. Furthermore, the bacterial motility assay showed that Δ mutants exhibited reduced motility compared to the parental strain. Transmission electron microscopy (TEM) showed a significant reduction in the number of flagella in the mutant Δ when compared with PCN033. To further explore the reasons why the deletion of affects the motility of PCN033, transcriptomic and metabolomic analyses were conducted. The omics analyses showed that 134 differentially accumulated metabolites and 2236 differentially expressed genes were identified between the mutant Δ and the parental strain PCN033. The metabolome profile and functional annotation analyses indicated that the impaired motility of Δ was connected to the downregulation of the expression levels of genes associated with the energy metabolism pathway and flagellar assembly. Our study provides a new insight into the diminished PCN033 motility induced by deletion. Moreover, the candidate genes and metabolites regulated by the gene in the T6SS, which was involved in the motility of PCN033, were reported in this study.