Expression of mucoid induction factor MucE is dependent upon the alternate sigma factor AlgU in Pseudomonas aeruginosa

BMC Microbiology

Research Article

T Ryan Withers¹  Hongwei D Yu²  F Heath Damron³  Yeshi Yin⁴  Michael J Schurr⁵  Christopher L Pritchett⁶  Xin Wang⁷ 

[1] Department of Biochemistry and Microbiology, Joan C. Edwards School of Medicine at Marshall University, 25755, Huntington, WV, USA;Department of Biochemistry and Microbiology, Joan C. Edwards School of Medicine at Marshall University, 25755, Huntington, WV, USA;Department of Pediatrics, Joan C. Edwards School of Medicine at Marshall University, 25755, Huntington, WV, USA;Progenesis Technologies, LLC, 1111 Veterans Memorial Blvd, 25701, Huntington, WV, USA;Department of Biochemistry and Microbiology, Joan C. Edwards School of Medicine at Marshall University, 25755, Huntington, WV, USA;Division of Infectious Diseases and International Health, University of Virginia, Box 800419, MR-6, 22908, Charlottesville, VA, USA;Department of Biochemistry and Microbiology, Joan C. Edwards School of Medicine at Marshall University, 25755, Huntington, WV, USA;Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, No. 198, Shiqiao Road, 310021, Hangzhou, China;Department of Microbiology, School of Medicine, University of Colorado, 80045, Aurora, Colorado, USA;Department of Microbiology, School of Medicine, University of Colorado, 80045, Aurora, Colorado, USA;Department of Health Sciences, East Tennessee State University, 37615, Johnson City, TN, USA;Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, No. 198, Shiqiao Road, 310021, Hangzhou, China;

关键词: Pseudomonas aeruginosa;    Alginate;    Mucoidy;    AlgU/T;    MucE;    Sigma factor;   

DOI  :  10.1186/1471-2180-13-232

 received in 2013-05-29, accepted in 2013-10-09,  发布年份 2013

来源: Springer

【 摘 要 】

BackgroundAlginate overproduction in P. aeruginosa, also referred to as mucoidy, is a poor prognostic marker for patients with cystic fibrosis (CF). We previously reported the construction of a unique mucoid strain which overexpresses a small envelope protein MucE leading to activation of the protease AlgW. AlgW then degrades the anti-sigma factor MucA thus releasing the alternative sigma factor AlgU/T (σ22) to initiate transcription of the alginate biosynthetic operon.ResultsIn the current study, we mapped the mucE transcriptional start site, and determined that PmucE activity was dependent on AlgU. Additionally, the presence of triclosan and sodium dodecyl sulfate was shown to cause an increase in PmucE activity. It was observed that mucE-mediated mucoidy in CF isolates was dependent on both the size of MucA and the genotype of algU. We also performed shotgun proteomic analysis with cell lysates from the strains PAO1, VE2 (PAO1 with constitutive expression of mucE) and VE2ΔalgU (VE2 with in-frame deletion of algU). As a result, we identified nine algU-dependent and two algU-independent proteins that were affected by overexpression of MucE.ConclusionsOur data indicates there is a positive feedback regulation between MucE and AlgU. Furthermore, it seems likely that MucE may be part of the signal transduction system that senses certain types of cell wall stress to P. aeruginosa.

【 授权许可】

Unknown   
© Yin et al.; licensee BioMed Central Ltd. 2013. This article is published under license to BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.