ExoS controls the cell contact-mediated switch to effector secretion in Pseudomonas aeruginosa.

ABSTRACT: Type III secretion is used by many gram-negative bacterial pathogens to directly deliver protein toxins (effectors) into targeted host cells. In all cases, secretion of effectors is triggered by host cell contact, although the mechanism is unclear. In Pseudomonas aeruginosa, expression of all type III secretion-related genes is up-regulated when secretion is triggered. We were able to visualize this process using a green fluorescent protein reporter system and to use it to monitor the ability of bacteria to trigger effector secretion on cell contact. Surprisingly, the action of one of the major type III secreted effectors, ExoS, prevented triggering of type III secretion by bacteria that subsequently attached to cells, suggesting that triggering of secretion is feedback regulated. Evidence

SUBMITTER: Cisz M 

PROVIDER: S-EPMC2293250 | biostudies-literature | 2008 Apr

REPOSITORIES: biostudies-literature