期刊
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
卷 104, 期 19, 页码 8107-8112出版社
NATL ACAD SCIENCES
DOI: 10.1073/pnas.0702660104
关键词
alginate; anti-sigma factor; PDZ domain; protease cascade; signal specificity
资金
- NCRR NIH HHS [P20RR16469, P20 RR016469] Funding Source: Medline
Overproduction of the exopolysaccharide alginate causes mucoid conversion in Pseudomonas aeruginosa and is a poor prognosticator in cystic fibrosis. The ECF sigma factor AlgU and its cognate anti-or 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 A aeruginosa strains PAO1 and PA14. Accumulation of MucE in the envelope resulted in increased AlgU activity and reduced MucA levels. Three critical amino acid residues at the C terminus of MucE (WVF) were required for mucoid conversion via two predicted proteases AlgW (DegS) and MucP (RseP/YaeL). Moreover, as in Escherichia coli, the PDZ domain of AlgW was required for signal transduction. These results suggest that AlgU is regulated similarly to E. Coli sigma(E) except that the amino acid triad signals from MucE and other envelope proteins that activate AlgW are slightly different from those activating DegS.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据