JB
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Supplemental material
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 Fuhrer, T.
Right arrow Articles by Sauer, U.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Fuhrer, T.
Right arrow Articles by Sauer, U.
Journal of Bacteriology, March 2005, p. 1581-1590, Vol. 187, No. 5
0021-9193/05/$08.00+0     doi:10.1128/JB.187.5.1581-1590.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.

Experimental Identification and Quantification of Glucose Metabolism in Seven Bacterial Species{dagger}

Tobias Fuhrer,1 Eliane Fischer,1 and Uwe Sauer1*

Institute of Biotechnology, ETH Zürich, Zürich, Switzerland1

Received 3 October 2004/ Accepted 17 November 2004

The structurally conserved and ubiquitous pathways of central carbon metabolism provide building blocks and cofactors for the biosynthesis of cellular macromolecules. The relative uses of pathways and reactions, however, vary widely among species and depend upon conditions, and some are not used at all. Here we identify the network topology of glucose metabolism and its in vivo operation by quantification of intracellular carbon fluxes from 13C tracer experiments. Specifically, we investigated Agrobacterium tumefaciens, two pseudomonads, Sinorhizobium meliloti, Rhodobacter sphaeroides, Zymomonas mobilis, and Paracoccus versutus, which grow on glucose as the sole carbon source, represent fundamentally different metabolic lifestyles (aerobic, anaerobic, photoheterotrophic, and chemoheterotrophic), and are phylogenetically distinct (firmicutes, {gamma}-proteobacteria, and {alpha}-proteobacteria). Compared to those of the model bacteria Escherichia coli and Bacillus subtilis, metabolisms of the investigated species differed significantly in several respects: (i) the Entner-Doudoroff pathway was the almost exclusive catabolic route; (ii) the pentose phosphate pathway exhibited exclusively biosynthetic functions, in many cases also requiring flux through the nonoxidative branch; (iii) all aerobes exhibited fully respiratory metabolism without significant overflow metabolism; and (iv) all aerobes used the pyruvate bypass of the malate dehydrogenase reaction to a significant extent. Exclusively, Pseudomonas fluorescens converted most glucose extracellularly to gluconate and 2-ketogluconate. Overall, the results suggest that metabolic data from model species with extensive industrial and laboratory history are not representative of microbial metabolism, at least not quantitatively.

* Corresponding author. Mailing address: Institute of Biotechnology, ETH Zürich, CH-8093 Zürich, Switzerland. Phone: 41-1-633 3672. Fax: 41-1-633 1051. E-mail: sauer{at}biotech.biol.ethz.ch.

{dagger} Supplemental material for this article may be found at http://jb.asm.org/.

Journal of Bacteriology, March 2005, p. 1581-1590, Vol. 187, No. 5
0021-9193/05/$08.00+0     doi:10.1128/JB.187.5.1581-1590.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
Appl. Environ. Microbiol. Infect. Immun. Eukaryot. Cell
Mol. Cell. Biol. J. Virol. Microbiol. Mol. Biol. Rev.
ALL ASM JOURNALS

Copyright © 2005 by the American Society for Microbiology. All rights reserved.