Open AccessCross‐talk towards the response regulator NtrC controlling nitrogen metabolism in Rhodobacter capsulatus
Author(s) -
Drepper Thomas,
Wiethaus Jessica,
Giaourakis Daphne,
Groß Silke,
Schubert Britta,
Vogt Markus,
Wiencek Yvonne,
McEwan Alastair G.,
Masepohl Bernd
Publication year - 2006
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.1574-6968.2006.00228.x
Subject(s) - rhodobacter , regulator , nitrogen cycle , chemistry , metabolism , microbiology and biotechnology , biology , biochemistry , nitrogen , gene , mutant , organic chemistry
Abstract Rhodobacter capsulatus NtrB/NtrC two‐component regulatory system controls expression of genes involved in nitrogen metabolism including urease and nitrogen fixation genes. The ntrY – ntrX genes, which are located immediately downstream of the nifR3 – ntrB – ntrC operon, code for a two‐component system of unknown function. Transcription of ntrY starts within the ntrC – ntrY intergenic region as shown by primer extension analysis, but maximal transcription requires, in addition, the promoter of the nifR3 – ntrB – ntrC operon. While ntrB and ntrY single mutant strains were able to grow with either urea or N 2 as sole nitrogen source, a ntrB / ntrY double mutant (like a ntrC ‐deficient strain) was no longer able to use urea or N 2 . These findings suggest that the histidine kinases NtrB and NtrY can substitute for each other as phosphodonors towards the response regulator NtrC.