You have full text access to this OnlineOpen article

Molecular studies on a new genetic locus linked to the common nodulation genes in Bradyrhizobium japonicum

  1. Sohail Luka†,*,
  2. Gary Stacey

Article first published online: 17 JAN 2006

DOI: 10.1111/j.1574-6968.1997.tb10280.x

Issue

FEMS Microbiology Letters

FEMS Microbiology Letters

Volume 148, Issue 2, pages 145–151, March 1997

Additional Information

How to Cite

Luka, S. and Stacey, G. (1997), Molecular studies on a new genetic locus linked to the common nodulation genes in Bradyrhizobium japonicum. FEMS Microbiology Letters, 148: 145–151. doi: 10.1111/j.1574-6968.1997.tb10280.x

Author Information

  1. Center for Legume Research, Department of Microbiology and Graduate Program of Ecology, M409 Walters Life Science Building, University of Tennessee, Knoxville, TN 37996-0845, USA

  1. †

    1International Institute of Genetics and Biophysics, Italian National Research Council, IIGB/CNR, Via Marconi 12, 80125 Naples, Italy.

* Corresponding author. Tel.: +39 (81) 725 7221; fax: +39 (81) 725 7202; e-mail: s.luka@agora.stm.it

Publication History

  1. Issue published online: 17 JAN 2006
  2. Article first published online: 17 JAN 2006
  3. Received 26 November 1996, Revised 4 December 1996, Accepted 13 December 1996

SEARCH

SEARCH BY CITATION

ARTICLE TOOLS

View Full Article (HTML) Get PDF (536K)

Keywords:

  • Bradyrhizobium;
  • nod gene;
  • Transcriptional control

Abstract

ORFA, an actively transcribed genetic locus linked to the common nodulation genes in Bradyrhizobium japonicum USDA110, was sequenced and analysed. The expression of ORFA is neither dependent on the regulatory proteins NifA, NtrC, NtrB and NodD1 nor on either copy of sigma 54, RpoN1 and RpoN2. The transcriptional start site of ORFA was determined and found to overlap the oppositely transcribed nodZ gene by 224 nucleotides. An appropriately located −10 sequence identical to the consensus proposed for rhizobia and a homologous −35 region were identified upstream of the transcriptional start site. ORFA showed no significant homologies to known sequences in gene databases, and its mutational inactivation had no effect on the nodulation of five legume species. Nevertheless, ORFA seems to be conserved among bradyrhizobia, since an ORFA probe hybridised to total DNA extracted from other Bradyrhizobium strains.

View Full Article (HTML) Get PDF (536K)