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 Renninger, N.
Right arrow Articles by Keasling, J. D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Renninger, N.
Right arrow Articles by Keasling, J. D.
Agricola
Right arrow Articles by Renninger, N.
Right arrow Articles by Keasling, J. D.

 Previous Article  |  Next Article 

Applied and Environmental Microbiology, December 2004, p. 7404-7412, Vol. 70, No. 12
0099-2240/04/$08.00+0     DOI: 10.1128/AEM.70.12.7404-7412.2004
Copyright © 2004, American Society for Microbiology. All Rights Reserved.

Uranyl Precipitation by Pseudomonas aeruginosa via Controlled Polyphosphate Metabolism

Neil Renninger,1 Roger Knopp,2 Heino Nitsche,2,3 Douglas S. Clark,1 and Jay D. Keasling1,4*

Department of Chemical Engineering,1 Department of Chemistry, University of California at Berkeley,3 The Glenn T. Seaborg Center,2 Synthetic Biology Department, Lawrence Berkeley National Laboratory, Berkeley, California4

Received 26 February 2004/ Accepted 16 August 2004

The polyphosphate kinase gene from Pseudomonas aeruginosa was overexpressed in its native host, resulting in the accumulation of 100 times the polyphosphate seen with control strains. Degradation of this polyphosphate was induced by carbon starvation conditions, resulting in phosphate release into the medium. The mechanism of polyphosphate degradation is not clearly understood, but it appears to be associated with glycogen degradation. Upon suspension of the cells in 1 mM uranyl nitrate, nearly all polyphosphate that had accumulated was degraded within 48 h, resulting in the removal of nearly 80% of the uranyl ion and >95% of lesser-concentrated solutions. Electron microscopy, energy-dispersive X-ray spectroscopy, and time-resolved laser-induced fluorescence spectroscopy (TRLFS) suggest that this removal was due to the precipitation of uranyl phosphate at the cell membrane. TRLFS also indicated that uranyl was initially sorbed to the cell as uranyl hydroxide and was then precipitated as uranyl phosphate as phosphate was released from the cell. Lethal doses of radiation did not halt phosphate secretion from polyphosphate-filled cells under carbon starvation conditions.

* Corresponding author. Mailing address: Department of Chemical Engineering, University of California at Berkeley, Berkeley, CA 94720-1462. Phone: (510) 642-4862. Fax: (510) 643-1228. E-mail: keasling{at}socrates.berkeley.edu.

Applied and Environmental Microbiology, December 2004, p. 7404-7412, Vol. 70, No. 12
0099-2240/04/$08.00+0     DOI: 10.1128/AEM.70.12.7404-7412.2004
Copyright © 2004, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Nilgiriwala, K. S., Alahari, A., Rao, A. S., Apte, S. K. (2008). Cloning and Overexpression of Alkaline Phosphatase PhoK from Sphingomonas sp. Strain BSAR-1 for Bioprecipitation of Uranium from Alkaline Solutions. Appl. Environ. Microbiol. 74: 5516-5523 [Abstract] [Full Text]  
  • Martinez, R. J., Wang, Y., Raimondo, M. A., Coombs, J. M., Barkay, T., Sobecky, P. A. (2006). Horizontal Gene Transfer of PIB-Type ATPases among Bacteria Isolated from Radionuclide- and Metal-Contaminated Subsurface Soils.. Appl. Environ. Microbiol. 72: 3111-3118 [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»