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
Google Scholar
Right arrow Articles by Hugouvieux-Cotte-Pattat, N.
Right arrow Articles by Charaoui-Boukerzaza, S.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Hugouvieux-Cotte-Pattat, N.
Right arrow Articles by Charaoui-Boukerzaza, S.

 Previous Article  |  Next Article 

Journal of Bacteriology, November 2009, p. 6960-6967, Vol. 191, No. 22
0021-9193/09/$08.00+0     doi:10.1128/JB.00594-09
Copyright © 2009, American Society for Microbiology. All Rights Reserved.

Catabolism of Raffinose, Sucrose, and Melibiose in Erwinia chrysanthemi 3937 {triangledown}

Nicole Hugouvieux-Cotte-Pattat* and Sana Charaoui-Boukerzaza

Université de Lyon, Université Lyon 1, INSA Lyon, Microbiologie Adaptation et Pathogénie CNRS UMR5240, Domaine Scientifique de la Doua, 69622 Villeurbanne Cedex, France

Received 7 May 2009/ Accepted 28 August 2009

Erwinia chrysanthemi (Dickeya dadantii) is a plant pathogenic bacterium that has a large capacity to degrade the plant cell wall polysaccharides. The present study reports the metabolic pathways used by E. chrysanthemi to assimilate the oligosaccharides sucrose and raffinose, which are particularly abundant plant sugars. E. chrysanthemi is able to use sucrose, raffinose, or melibiose as a sole carbon source for growth. The two gene clusters scrKYABR and rafRBA are necessary for their catabolism. The phenotypic analysis of scr and raf mutants revealed cross-links between the assimilation pathways of these oligosaccharides. Sucrose catabolism is mediated by the genes scrKYAB. While the raf cluster is sufficient to catabolize melibiose, it is incomplete for raffinose catabolism, which needs two additional steps that are provided by scrY and scrB. The scr and raf clusters are controlled by specific repressors, ScrR and RafR, respectively. Both clusters are controlled by the global activator of carbohydrate catabolism, the cyclic AMP receptor protein (CRP). E. chrysanthemi growth with lactose is possible only for mutants with a derepressed nonspecific lactose transport system, which was identified as RafB. RafR inactivation allows the bacteria to the assimilate the novel substrates lactose, lactulose, stachyose, and melibionic acid. The raf genes also are involved in the assimilation of {alpha}- and β-methyl-D-galactosides. Mutations in the raf or scr genes did not significantly affect E. chrysanthemi virulence. This could be explained by the large variety of carbon sources available in the plant tissue macerated by E. chrysanthemi.

* Corresponding author. Mailing address: Microbiologie Adaptation et Pathogénie UMR5240, batiment Lwoff, 10 rue Dubois, Domaine Scientifique de la Doua, 69622 Villeurbanne Cedex, France. Phone: 33-472-43-1553. Fax: 33-472-43-1584. E-mail: Nicole.Cotte-Pattat{at}insa-lyon.fr

{triangledown} Published ahead of print on 4 September 2009.

Journal of Bacteriology, November 2009, p. 6960-6967, Vol. 191, No. 22
0021-9193/09/$08.00+0     doi:10.1128/JB.00594-09
Copyright © 2009, American Society for Microbiology. All Rights Reserved.





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