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 Google Scholar
Google Scholar
Right arrow Articles by Herve-Jimenez, L.
Right arrow Articles by Rul, F.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Herve-Jimenez, L.
Right arrow Articles by Rul, F.
Agricola
Right arrow Articles by Herve-Jimenez, L.
Right arrow Articles by Rul, F.

 Previous Article  |  Next Article 

Applied and Environmental Microbiology, April 2009, p. 2062-2073, Vol. 75, No. 7
0099-2240/09/$08.00+0     doi:10.1128/AEM.01984-08
Copyright © 2009, American Society for Microbiology. All Rights Reserved.

Postgenomic Analysis of Streptococcus thermophilus Cocultivated in Milk with Lactobacillus delbrueckii subsp. bulgaricus: Involvement of Nitrogen, Purine, and Iron Metabolism{triangledown} ,{dagger}

Luciana Herve-Jimenez,1,2,{ddagger} Isabelle Guillouard,2 Eric Guedon,2 Samira Boudebbouze,2 Pascal Hols,3 Véronique Monnet,1 Emmanuelle Maguin,2 and Françoise Rul1*

INRA, UR477 Biochimie Bactérienne, F-78350 Jouy-en-Josas, France,1 INRA, UR895 Génétique Microbienne, F-78350 Jouy-en-Josas, France,2 Unité de Génétique, Institut des Sciences de la Vie, Université Catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium3

Received 26 August 2008/ Accepted 22 December 2008

Streptococcus thermophilus is one of the most widely used lactic acid bacteria in the dairy industry, in particular in yoghurt manufacture, where it is associated with Lactobacillus delbrueckii subsp. bulgaricus. This bacterial association, known as a proto-cooperation, is poorly documented at the molecular and regulatory levels. We thus investigate the kinetics of the transcriptomic and proteomic modifications of S. thermophilus LMG 18311 in response to the presence of L. delbrueckii subsp. bulgaricus ATCC 11842 during growth in milk at two growth stages. Seventy-seven different genes or proteins (4.1% of total coding sequences), implicated mainly in the metabolism of nitrogen (24%), nucleotide base (21%), and iron (20%), varied specifically in coculture. One of the most unpredicted results was a significant decrease of most of the transcripts and enzymes involved in purine biosynthesis. Interestingly, the expression of nearly all genes potentially encoding iron transporters of S. thermophilus decreased, whereas that of iron-chelating dpr as well as that of the fur (perR) regulator genes increased, suggesting a reduction in the intracellular iron concentration, probably in response to H2O2 production by L. bulgaricus. The present study reveals undocumented nutritional exchanges and regulatory relationships between the two yoghurt bacteria, which provide new molecular clues for the understanding of their associative behavior.

* Corresponding author. Mailing address: Unité de Biochimie Bactérienne, INRA, 78350 Jouy-en-Josas, France. Phone: 33 (0)1 34 65 21 48. Fax: 33 (0)1 34 65 21 63. E-mail: francoise.rul{at}jouy.inra.fr

{triangledown} Published ahead of print on 29 December 2008.

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

{ddagger} Present address: Chr. Hansen, Arpajon, France.

Applied and Environmental Microbiology, April 2009, p. 2062-2073, Vol. 75, No. 7
0099-2240/09/$08.00+0     doi:10.1128/AEM.01984-08
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»