Overproduction of the AlgT Sigma Factor Is Lethal to Mucoid Pseudomonas aeruginosa.

ABSTRACT: Pseudomonas aeruginosa isolates from chronic lung infections often overproduce alginate, giving rise to the mucoid phenotype. Isolation of mucoid strains from chronic lung infections correlates with a poor patient outcome. The most common mutation that causes the mucoid phenotype is called mucA22 and results in a truncated form of the anti-sigma factor MucA that is continuously subjected to proteolysis. When a functional MucA is absent, the cognate sigma factor, AlgT, is no longer sequestered and continuously transcribes the alginate biosynthesis operon, leading to alginate overproduction. In this work, we report that in the absence of wild-type MucA, providing exogenous AlgT is toxic. This is intriguing, since mucoid strains endogenously possess high levels of AlgT. Furtherm

SUBMITTER: Cross AR 

PROVIDER: S-EPMC7515251 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature