DNA binding activity of NtrC from Rhizobium grown on different nitrogen sources

FEBS Letters

Colonna-Romano, Sergio¹  Iaccarino, Maurizio¹  Riccio, Anna¹  Defez, Roberto¹  Patriarca, Eduardo J.¹ 

[1] International Institute of Genetics and Biophysics, CNR, Via Marconi 10, 80125 Naples, Italy

关键词: Two-component system;    Nitrogen regulation;    Gel retardation;    PMSF;    phenylmethylsulfonyl fluoride;    HEPES;    N-(2-hydroxyethyl)piperazine-N′-(ethanesulfonic acid);    EDTA;    (ethylenedinitrilo)tetraacetic acid;   

DOI  :  10.1016/0014-5793(94)01094-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The DNA-binding activity of the NtrC protein can be demonstrated in gel retardation assays with concentrated protein extracts of Rhizobium etli. Using extracts from either the wild type or a ntrC mutant strain and an antiserum raised against the NtrC protein, we demonstrate specific binding of NtrC to the upstream regulatory region of the glnII gene, where two putative NtrC-binding sites are present. KNO₃-grown bacteria contain less NtrC protein and more NtrC-binding activity than NH₄Cl-grown bacteria, thus showing that with this protocol it is possible to detect changes in NtrC-binding activity. The advantages of this assay system in comparison with that using pure proteins is discussed.

【 授权许可】

Unknown