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 Moreau, P. L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Moreau, P. L.

 Previous Article  |  Next Article 

Journal of Bacteriology, November 2004, p. 7364-7368, Vol. 186, No. 21
0021-9193/04/$08.00+0     DOI: 10.1128/JB.186.21.7364-7368.2004
Copyright © 2004, American Society for Microbiology. All Rights Reserved.

Diversion of the Metabolic Flux from Pyruvate Dehydrogenase to Pyruvate Oxidase Decreases Oxidative Stress during Glucose Metabolism in Nongrowing Escherichia coli Cells Incubated under Aerobic, Phosphate Starvation Conditions{dagger}

Patrice L. Moreau*

Laboratoire de Chimie Bactérienne, Centre National de la Recherche Scientifique, 13009 Marseille, France

Received 10 May 2004/ Accepted 26 July 2004

Ongoing aerobic metabolism in nongrowing cells may generate oxidative stress. It is shown here that the levels of thiobarbituric acid-reactive substances (TBARSs), which measure fragmentation products of oxidized molecules, increased strongly at the onset of starvation for phosphate (Pi). This increase in TBARS levels required the activity of the histone-like nucleoid-structuring (H-NS) protein. TBARS levels weakly increased further in {Delta}ahpCF mutants deficient in alkyl hydroperoxide reductase (AHP) activity during prolonged metabolism of glucose to acetate. Inactivation of pyruvate oxidase (PoxB) activity decreased the production of acetate by half and significantly increased the production of TBARS. Overall, these data suggest that during incubation under aerobic, Pi starvation conditions, metabolic flux is diverted from the pyruvate dehydrogenase (PDH) complex (NAD dependent) to PoxB (NAD independent). This shift may decrease the production of NADH and in turn the adventitious production of H2O2 by NADH dehydrogenase in the respiratory chain. The residual low levels of H2O2 produced during prolonged incubation can be scavenged efficiently by AHP. However, high levels of H2O2 may be reached transiently at the onset of stationary phase, primarily because H-NS may delay the metabolic shift from PDH to PoxB.

* Mailing address: CNRS-LCB, 31 Chemin J. Aiguier, 13009 Marseille, France. Phone: (33) 4 91 16 43 53. Fax: (33) 4 91 71 89 14. E-mail: moreau{at}ibsm.cnrs-mrs.fr.

{dagger} This paper is dedicated to the memory of Benjamin Moreau (1977-2000).

Journal of Bacteriology, November 2004, p. 7364-7368, Vol. 186, No. 21
0021-9193/04/$08.00+0     DOI: 10.1128/JB.186.21.7364-7368.2004
Copyright © 2004, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Guillemet, M. L., Moreau, P. L. (2008). Fur-Dependent Detoxification of Organic Acids by rpoS Mutants during Prolonged Incubation under Aerobic, Phosphate Starvation Conditions. J. Bacteriol. 190: 5567-5575 [Abstract] [Full Text]  
  • Moreau, P. L. (2007). The Lysine Decarboxylase CadA Protects Escherichia coli Starved of Phosphate against Fermentation Acids. J. Bacteriol. 189: 2249-2261 [Abstract] [Full Text]  
  • Korshunov, S., Imlay, J. A. (2006). Detection and Quantification of Superoxide Formed within the Periplasm of Escherichia coli.. J. Bacteriol. 188: 6326-6334 [Abstract] [Full Text]  
  • Schreiner, M. E., Riedel, C., Holatko, J., Patek, M., Eikmanns, B. J. (2006). Pyruvate:Quinone Oxidoreductase in Corynebacterium glutamicum: Molecular Analysis of the pqo Gene, Significance of the Enzyme, and Phylogenetic Aspects. J. Bacteriol. 188: 1341-1350 [Abstract] [Full Text]  
  • Jerman, B., Butala, M., Zgur-Bertok, D. (2005). Sublethal Concentrations of Ciprofloxacin Induce Bacteriocin Synthesis in Escherichia coli. Antimicrob. Agents Chemother. 49: 3087-3090 [Abstract] [Full Text]  
  • Schreiner, M. E., Eikmanns, B. J. (2005). Pyruvate:Quinone Oxidoreductase from Corynebacterium glutamicum: Purification and Biochemical Characterization. J. Bacteriol. 187: 862-871 [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»