This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Silo-Suh, L.
Right arrow Articles by Ohman, D. E.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Silo-Suh, L.
Right arrow Articles by Ohman, D. E.

 Previous Article  |  Next Article 

Journal of Bacteriology, November 2005, p. 7561-7568, Vol. 187, No. 22
0021-9193/05/$08.00+0     doi:10.1128/JB.187.22.7561-7568.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.

Adaptations of Pseudomonas aeruginosa to the Cystic Fibrosis Lung Environment Can Include Deregulation of zwf, Encoding Glucose-6-Phosphate Dehydrogenase

Laura Silo-Suh,1* Sang-Jin Suh,1 Paul V. Phibbs,2 and Dennis E. Ohman3,4

Department of Biological Sciences, Auburn University, Auburn, Alabama 36849,1 Department of Microbiology and Immunology, East Carolina University School of Medicine, Greenville, North Carolina 27858,2 Department of Microbiology and Immunology, Medical College of Virginia Campus of Virginia Commonwealth University, Richmond, Virginia 23298-0678,3 McGuire Veterans Affairs Medical Center, Richmond, Virginia 232494

Received 2 June 2005/ Accepted 25 August 2005

Cystic fibrosis (CF) patients are highly susceptible to chronic pulmonary disease caused by mucoid Pseudomonas aeruginosa strains that overproduce the exopolysaccharide alginate. We showed here that a mutation in zwf, encoding glucose-6-phosphate dehydrogenase (G6PDH), leads to a ~90% reduction in alginate production in the mucoid, CF isolate, P. aeruginosa FRD1. The main regulator of alginate, sigma-22 encoded by algT (algU), plays a small but demonstrable role in the induction of zwf expression in P. aeruginosa. However, G6PDH activity and zwf expression were higher in FRD1 strains than in PAO1 strains. In PAO1, zwf expression and G6PDH activity are known to be subject to catabolite repression by succinate. In contrast, FRD1 zwf expression and G6PDH activity were shown to be refractory to such catabolite repression. This was apparently not due to a defect in the catabolite repression control (Crc) protein. Such relaxed control of zwf was found to be common among several examined CF isolates but was not seen in other strains of clinical and environmental origin. Two sets of clonal isolates from individual CF patient indicated that the resident P. aeruginosa strain underwent an adaptive change that deregulated zwf expression. We hypothesized that high-level, unregulated G6PDH activity provided a survival advantage to P. aeruginosa within the lung environment. Interestingly, zwf expression in P. aeruginosa was shown to be required for its resistance to human sputum. This study illustrates that adaptation to the CF pulmonary environment by P. aeruginosa can include altered regulation of basic metabolic activities, including carbon catabolism.

* Corresponding author. Mailing address: Dept. of Biological Sciences, 314 Life Sciences, Auburn University, Auburn, AL 36849. Phone: (334) 844-1338. Fax: (334) 844-1645. E-mail: suhlaur{at}auburn.edu.

Journal of Bacteriology, November 2005, p. 7561-7568, Vol. 187, No. 22
0021-9193/05/$08.00+0     doi:10.1128/JB.187.22.7561-7568.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Lindsey, T. L., Hagins, J. M., Sokol, P. A., Silo-Suh, L. A. (2008). Virulence determinants from a cystic fibrosis isolate of Pseudomonas aeruginosa include isocitrate lyase. Microbiology 154: 1616-1627 [Abstract] [Full Text]  
  • Marr, A. K., Overhage, J., Bains, M., Hancock, R. E. W. (2007). The Lon protease of Pseudomonas aeruginosa is induced by aminoglycosides and is involved in biofilm formation and motility. Microbiology 153: 474-482 [Abstract] [Full Text]  
  • Duque, E., Rodriguez-Herva, J.-J., de la Torre, J., Dominguez-Cuevas, P., Munoz-Rojas, J., Ramos, J.-L. (2007). The RpoT Regulon of Pseudomonas putida DOT-T1E and Its Role in Stress Endurance against Solvents. J. Bacteriol. 189: 207-219 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»