This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Baginsky, C. Articles by Ruiz-Argüeso, T. Search for Related Content PubMed PubMed Citation Articles by Baginsky, C. Articles by Ruiz-Argüeso, T. Agricola Articles by Baginsky, C. Articles by Ruiz-Argüeso, T.

 Previous Article  |  Next Article 

Applied and Environmental Microbiology, October 2002, p. 4915-4924, Vol. 68, No. 10
0099-2240/02/$04.00+0     DOI: 10.1128/AEM.68.10.4915-4924.2002
Copyright © 2002, American Society for Microbiology. All Rights Reserved.

Diversity and Evolution of Hydrogenase Systems in Rhizobia

Cecilia Baginsky,¹ Belén Brito,¹ Juan Imperial,² José-Manuel Palacios,¹ and Tomás Ruiz-Argüeso^1*

Laboratorio de Microbiología, E.T.S. Ingenieros Agrónomos, Universidad Politécnica de Madrid,¹ Consejo Superior de Investigaciones Científicas (CSIC), Ciudad Universitaria s/n, 28040 Madrid, Spain²

Received 30 April 2002/ Accepted 29 July 2002

Uptake hydrogenases allow rhizobia to recycle the hydrogen generated in the nitrogen fixation process within the legume nodule. Hydrogenase (hup) systems in Bradyrhizobium japonicum and Rhizobium leguminosarum bv. viciae show highly conserved sequence and gene organization, but important differences exist in regulation and in the presence of specific genes. We have undertaken the characterization of hup gene clusters from Bradyrhizobium sp. (Lupinus), Bradyrhizobium sp. (Vigna), and Rhizobium tropici and Azorhizobium caulinodans strains with the aim of defining the extent of diversity in hup gene composition and regulation in endosymbiotic bacteria. Genomic DNA hybridizations using hupS, hupE, hupUV, hypB, and hoxA probes showed a diversity of intraspecific hup profiles within Bradyrhizobium sp. (Lupinus) and Bradyrhizobium sp. (Vigna) strains and homogeneous intraspecific patterns within R. tropici and A. caulinodans strains. The analysis also revealed differences regarding the possession of hydrogenase regulatory genes. Phylogenetic analyses using partial sequences of hupS and hupL clustered R. leguminosarum and R. tropici hup sequences together with those from B. japonicum and Bradyrhizobium sp. (Lupinus) strains, suggesting a common origin. In contrast, Bradyrhizobium sp. (Vigna) hup sequences diverged from the rest of rhizobial sequences, which might indicate that those organisms have evolved independently and possibly have acquired the sequences by horizontal transfer from an unidentified source.

---

* Corresponding author. Mailing address: Laboratorio de Microbiología, E.T.S. Ingenieros Agrónomos, Universidad Politécnica de Madrid, 28040 Madrid, Spain. Phone: 34-913365759. Fax: 34-913365757. E-mail: ruizargueso{at}bit.etsia.upm.es.

---

Applied and Environmental Microbiology, October 2002, p. 4915-4924, Vol. 68, No. 10
0099-2240/02/$04.00+0     DOI: 10.1128/AEM.68.10.4915-4924.2002
Copyright © 2002, American Society for Microbiology. All Rights Reserved.

This article has been cited by other articles:

• Baginsky, C., Brito, B., Imperial, J., Ruiz-Argueso, T., Palacios, J. M. (2005). Symbiotic Hydrogenase Activity in Bradyrhizobium sp. (Vigna) Increases Nitrogen Content in Vigna unguiculata Plants. Appl. Environ. Microbiol. 71: 7536-7538 [Abstract] [Full Text]  
• Parro, V., Moreno-Paz, M. (2003). Gene function analysis in environmental isolates: The nif regulon of the strict iron oxidizing bacterium Leptospirillum ferrooxidans. Proc. Natl. Acad. Sci. USA 100: 7883-7888 [Abstract] [Full Text]