Figure 9

Schematic diagram of the proposed mechanism of Ndk-mediated virulence regulation.
Upon P. aeruginosa infection, ndk expression was down-regulated in the pulmonary alveoli of mouse model of acute pneumonia. Knockout of ndk inhibited the las, rhl and pqs QS system. The inhibited rhl and pqs systems promoted T3SS gene and protein expression levels in an ExsA-dependent manner. The suppressed rhl system decreased exoproduct-related gene expression and product synthesis. In general, the inhibition of ndk promoted P. aeruginosa cytotoxicity and host pathogenicity through T3SS activation.