Medicine and Health Sciences Commons^™

Regulated Proteolysis Controls Mucoid Conversion In Pseudomonas Aeruginosa, Dongru Qiu, Vonya Eisinger, Donald Rowen, Hongwei Yu

Hongwei Yu

Overproduction of the exopolysaccharide alginate causes mucoid conversion in Pseudomonas aeruginosa and is a poor prognosticator in cystic fibrosis. The ECF σ factor AlgU and its cognate anti-σ factor MucA are two principal regulators of alginate production. Here, we report the identification of three positive regulators of alginate biosynthesis: PA4033 (designated mucE), PA3649 (designated mucP), and algW. MucE, a small protein (9.5 kDa), was identified as part of a global mariner transposon screen for new regulators of alginate production. A transposon located in its promoter caused the overexpression of MucE and mucoid conversion in P. aeruginosa strains PAO1 and PA14. …