Control of AlgU, a member of the sigma E-like family of stress sigma factors, by the negative regulators MucA and MucB and Pseudomonas aeruginosa conversion to mucoidy in cystic fibrosis

• DOI: 10.1128/jb.178.16.4997-5004.1996
• Publication Date: 2016-11-10T13:07:42Z
• Authors: M J Schurr; H Yu; J M Martinez-Salazar; J C Boucher; V Deretic
• Keywords: Sigma factor

The alternative sigma factor AlgU (Pseudomonas aeruginosa E) is required for full resistance of P. to oxidative stress and extreme temperatures. also controls conversion the mucoid, alginate-overproducing phenotype associated with lethal infections in cystic fibrosis patients. Mutations that cause mucoidy isolates occur frequently mucA, second gene within algU mucABCD cluster. Here we analyze biochemical basis mucoidy. MucA was shown act as an anti-sigma by binding inhibiting its activity. MucB, another negative regulator AlgU, localized periplasm. MucB exerts function from this compartment, since deletion leader peptide cytoplasmic location abrogated ability inhibit These data support a model which multicomponent system, encompassing anti-delta elements periplasmic modulates activity AlgU. Since factors controlling are conserved other gram-negative bacteria, processes may be applicable regulation (sigma equivalents organisms.