Open AccessInteraction of an IHF‐like protein with the Rhizobium etli nifA promoter
Author(s) -
Benhassine Traki,
Fauvart Maarten,
Vanderleyden Jos,
Michiels Jan
Publication year - 2007
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2007.00699.x
Subject(s) - biology , rhizobium , transcription factor , gene , escherichia coli , electrophoretic mobility shift assay , transcription (linguistics) , microbiology and biotechnology , promoter , affinity chromatography , sepharose , dna , biochemistry , gene expression , linguistics , philosophy , enzyme
The nifA gene fulfills an essential role in the regulation of nitrogen fixation genes in Rhizobium etli . Transcription analysis of the nifA gene, assessed using promoter deletions, indicated an oxygen‐independent expression, threefold higher during symbiosis as compared with free‐living conditions. Electrophoretic mobility shift assays using those nifA promoter deletion fragments, which were actively transcribed, demonstrated the specific interaction with R . etli cellular protein(s) resulting in the formation of two DNA–protein complexes. An interacting protein was purified by liquid chromatography on Heparin Sepharose and Mono S columns. The purified 12 kDa R . etli protein cross‐reacted with antibodies directed against Escherichia coli integration host factor (IHF). Furthermore, purified E . coli IHF was able to specifically bind to the R . etli nifA promoter region. These results point to an as yet undisclosed function of IHF in the regulation of R . etli nifA expression.