Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

Mutations in a Rhizobium leguminosarum gene, rirA (rhizobial iron regulator), caused high-level, constitutive expression of at least eight operons whose transcription is normally Fe-responsive and whose products are involved in the synthesis or uptake of siderophores, or in the uptake of haem or of other iron sources. Close homologues of RirA exist in other rhizobia and in the pathogen Brucella; many other bacteria have deduced proteins with more limited sequence similarity. None of these homologues had been implicated in Fe-mediated gene regulation. Transcription of rirA itself is about twofold higher in cells grown in Fe-replete than in Fe-deficient growth media. Mutations in rirA reduced growth rates in Fe-replete and -depleted medium, but did not appear to affect symbiotic N(2) fixation.

Original publication

DOI

10.1099/00221287-148-12-4059

Type

Journal article

Journal

Microbiology

Publication Date

12/2002

Volume

148

Pages

4059 - 4071

Keywords

Amino Acid Sequence, Bacterial Proteins, Base Sequence, Cloning, Molecular, Gene Expression Regulation, Bacterial, Iron, Molecular Sequence Data, Mutation, Nitrogen Fixation, Operon, Promoter Regions, Genetic, Rhizobium leguminosarum, Sequence Analysis, DNA, Siderophores, Symbiosis