Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Site Tools

  • AAAS
  • Subscribe
  • Feedback

Site Search

Search Advanced

Science 1 June 2007:
Vol. 316. no. 5829, pp. 1307 - 1312
DOI: 10.1126/science.1139548
Prev | Table of Contents | Next

Research Articles

Legumes Symbioses: Absence of Nod Genes in Photosynthetic Bradyrhizobia

Eric Giraud,1*{dagger} Lionel Moulin,1 David Vallenet,2 Valérie Barbe,3 Eddie Cytryn,4 Jean-Christophe Avarre,1 Marianne Jaubert,1 Damien Simon,1 Fabienne Cartieaux,1 Yves Prin,1 Gilles Bena,1 Laure Hannibal,1 Joel Fardoux,1 Mila Kojadinovic,5 Laurie Vuillet,1 Aurélie Lajus,2 Stéphane Cruveiller,2 Zoe Rouy,2 Sophie Mangenot,3 Béatrice Segurens,3 Carole Dossat,3 William L. Franck,6 Woo-Suk Chang,6 Elizabeth Saunders,7 David Bruce,7 Paul Richardson,8 Philippe Normand,9 Bernard Dreyfus,1 David Pignol,5 Gary Stacey,6 David Emerich,6 André Verméglio,5 Claudine Médigue,2 Michael Sadowsky4*{dagger}

Leguminous plants (such as peas and soybeans) and rhizobial soil bacteria are symbiotic partners that communicate through molecular signaling pathways, resulting in the formation of nodules on legume roots and occasionally stems that house nitrogen-fixing bacteria. Nodule formation has been assumed to be exclusively initiated by the binding of bacterial, host-specific lipochito-oligosaccharidic Nod factors, encoded by the nodABC genes, to kinase-like receptors of the plant. Here we show by complete genome sequencing of two symbiotic, photosynthetic, Bradyrhizobium strains, BTAi1 and ORS278, that canonical nodABC genes and typical lipochito-oligosaccharidic Nod factors are not required for symbiosis in some legumes. Mutational analyses indicated that these unique rhizobia use an alternative pathway to initiate symbioses, where a purine derivative may play a key role in triggering nodule formation.

1 Laboratoire des Symbioses Tropicales et Méditerranéennes, Unité mixte recherche (UMR) 113, Institut de Recherche pour le Développement, Centre de Coopération International en Recherche Agronomique pour le Développement, AGRO Montpellier, Institut National de la Recherche Agronomique, Université Montpellier 2, TA A-82/J, Campus de Baillarguet, 34398 Montpellier Cedex 5, France.
2 Genoscope, CNRS–UMR 8030, Atelier de Génomique Comparative, 2 rue Gaston Crémieux BP5706, 91057 Evry Cedex, France.
3 Genoscope, Centre National de Séquençage, 2 rue Gaston Crémieux BP5706, 91057 Evry Cedex, France.
4 Department of Soil, Water, and Climate; BioTechnology Institute; and Microbial and Plant Genomics Institute, University of Minnesota, 1991 Upper Buford Circle, 439 BorH, St. Paul, MN, 55108, USA.
5 Commissariat à l'Energie Atomique (CEA) Cadarache, Direction des Sciences du Vivant, Institut de Biologie Environnementale et Biotechnologie, Service de Biologie Végétale et de Microbiologie Environnementale, Laboratoire de Bioénenergétique Cellulaire (DSV/IBEB/SBVME/LBC), UMR 6191 CNRS/CEA/Université Aix-Marseille, Saint-Paul-lez-Durance, F-13108 France.
6 National Center for Soybean Biotechnology, Divisions of Plant Sciences and Biochemistry, Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, MO, 65211, USA.
7 U.S. Department of Energy (DOE) Joint Genome Institute, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
8 DOE Joint Genome Institute, Walnut Creek, CA 94598, USA.
9 Université Lyon1, CNRS, UMR 5557, Ecologie Microbienne, Lyon, F-69003, France.

{dagger} E.G. and M.S. coordinated the sequence annotation of the Bradyrhizobium ORS278 and BTAi1 genomes, respectively.

* To whom correspondence should be addressed. E-mail: giraud{at}mpl.ird.fr; sadowsky{at}umn.edu.

Read the Full Text


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Rhizobium sp. Strain NGR234 Possesses a Remarkable Number of Secretion Systems.
C. Schmeisser, H. Liesegang, D. Krysciak, N. Bakkou, A. Le Quere, A. Wollherr, I. Heinemeyer, B. Morgenstern, A. Pommerening-Roser, M. Flores, et al. (2009)
Appl. Envir. Microbiol. 75, 4035-4045
   Abstract »    Full Text »    PDF »
Role of Potassium Uptake Systems in Sinorhizobium meliloti Osmoadaptation and Symbiotic Performance.
A. Dominguez-Ferreras, S. Munoz, J. Olivares, M. J. Soto, and J. Sanjuan (2009)
J. Bacteriol. 191, 2133-2143
   Abstract »    Full Text »    PDF »
Genetic Diversity and Host Range of Rhizobia Nodulating Lotus tenuis in Typical Soils of the Salado River Basin (Argentina).
M. J. Estrella, S. Munoz, M. J. Soto, O. Ruiz, and J. Sanjuan (2009)
Appl. Envir. Microbiol. 75, 1088-1098
   Abstract »    Full Text »    PDF »
De Novo Organ Formation from Differentiated Cells: Root Nodule Organogenesis.
M. Crespi and F. Frugier (2008)
Science Signaling 1, re11
   Abstract »    Full Text »    PDF »
Comprehensive Assessment of the Regulons Controlled by the FixLJ-FixK2-FixK1 Cascade in Bradyrhizobium japonicum.
S. Mesa, F. Hauser, M. Friberg, E. Malaguti, H.-M. Fischer, and H. Hennecke (2008)
J. Bacteriol. 190, 6568-6579
   Abstract »    Full Text »    PDF »
Construction of Signature-tagged Mutant Library in Mesorhizobium loti as a Powerful Tool for Functional Genomics.
Y. Shimoda, H. Mitsui, H. Kamimatsuse, K. Minamisawa, E. Nishiyama, Y. Ohtsubo, Y. Nagata, M. Tsuda, S. Shinpo, A. Watanabe, et al. (2008)
DNA Res 15, 297-308
   Abstract »    Full Text »    PDF »
Root-Microbe Communication through Protein Secretion.
C. De-la-Pena, Z. Lei, B. S. Watson, L. W. Sumner, and J. M. Vivanco (2008)
J. Biol. Chem. 283, 25247-25255
   Abstract »    Full Text »    PDF »
Genome sequence of the {beta}-rhizobium Cupriavidus taiwanensis and comparative genomics of rhizobia.
C. Amadou, G. Pascal, S. Mangenot, M. Glew, C. Bontemps, D. Capela, S. Carrere, S. Cruveiller, C. Dossat, A. Lajus, et al. (2008)
Genome Res. 18, 1472-1483
   Abstract »    Full Text »    PDF »
60Ma of legume nodulation. What's new? What's changing?.
J. I. Sprent (2008)
J. Exp. Bot. 59, 1081-1084
   Abstract »    Full Text »    PDF »
Advances in environmental genomics: towards an integrated view of micro-organisms and ecosystems.
P. N. Bertin, C. Medigue, and P. Normand (2008)
Microbiology 154, 347-359
   Abstract »    Full Text »    PDF »
A Large Scale Analysis of Protein-Protein Interactions in the Nitrogen-fixing Bacterium Mesorhizobium loti.
Y. Shimoda, S. Shinpo, M. Kohara, Y. Nakamura, S. Tabata, and S. Sato (2008)
DNA Res 15, 13-23
   Abstract »    Full Text »    PDF »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)