Suppression of Pseudomonas aeruginosa type III secretion system by a novel calcium-responsive signaling pathway.

ABSTRACT: Expression of the type III secretion system (T3SS) in Pseudomonas aeruginosa is exquisitely controlled by diverse environmental or host-related signals such as calcium (Ca²⁺), however, the signal transduction pathways remain largely elusive. In this study, we reported that FleR, the response regulator of the two-component system FleS/FleR, inhibits T3SS gene expression and virulence of P. aeruginosa uncoupled from its cognate histidine kinase FleS. Interestingly, FleR was found to repress T3SS gene expression under Ca²⁺-rich conditions independently of its DNA-binding domain. FleR activates the elevation of intracellular c-di-GMP contents and FleQ serves as the c-di-GMP effector to repress T3SS gene expression through the Gac/Rsm pathway. Remarkably, we

SUBMITTER: Huang J 

PROVIDER: S-EPMC11039405 | biostudies-literature | 2024 May

REPOSITORIES: biostudies-literature