Pseudomonas aeruginosa Effector ExoS Inhibits ROS Production in Human Neutrophils.

ABSTRACT: Neutrophils are the first line of defense against bacterial infections, and the generation of reactive oxygen species is a key part of their arsenal. Pathogens use detoxification systems to avoid the bactericidal effects of reactive oxygen species. Here we demonstrate that the Gram-negative pathogen Pseudomonas aeruginosa is susceptible to reactive oxygen species but actively blocks the reactive oxygen species burst using two type III secreted effector proteins, ExoS and ExoT. ExoS ADP-ribosylates Ras and prevents it from interacting with and activating phosphoinositol-3-kinase (PI3K), which is required to stimulate the phagocytic NADPH-oxidase that generates reactive oxygen species. ExoT also affects PI3K signaling via its ADP-ribosyltransferase activity but does not act directly on Ras.

SUBMITTER: Vareechon C 

PROVIDER: S-EPMC5478421 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature