TnrA

• Description: transcriptional pleiotropic regulator invoved in global nitrogen regulation
  
  

Gene name	tnrA
Synonyms	scgR
Essential	no
Product	transcription activator/ repressor
Function	regulation of nitrogen assimilation
Gene expression levels in SubtiExpress: tnrA
Interactions involving this protein in SubtInteract: TnrA
Metabolic function and regulation of this protein in SubtiPathways: Lipid synthesis, Nucleotides (regulation), Ile, Leu, Val, Ammonium/ glutamate, Central C-metabolism, Cell wall, Coenzyme A, Phosphorelay, Alternative nitrogen sources
MW, pI	12 kDa, 10.235
Gene length, protein length	330 bp, 110 aa
Immediate neighbours	mgtE, ykzB
Get the DNA and protein sequences (Barbe et al., 2009)
Genetic context This image was kindly provided by SubtiList
Expression at a glance   PubMed

Categories containing this gene/protein

biosynthesis/ acquisition of amino acids, glutamate metabolism, transcription factors and their control, regulators of core metabolism

This gene is a member of the following regulons

GlnR regulon, TnrA regulon

The gene

Basic information

• Locus tag: BSU13310

Database entries

• DBTBS entry: [1]

• SubtiList entry: [2]

The protein

Basic information/ Evolution

• Catalyzed reaction/ biological activity:

• Protein family:

• Paralogous protein(s):

Extended information on the protein

• Kinetic information:
  • K(D) value for the binding site in the tnrA promoter region: 55 nM PubMed

• Domains:

• Modification:

• Cofactor(s):

• Effectors of protein activity: feedback-inhibited GlnA prevents TnrA from DNA binding

• Interactions:
  • TnrA-NrgB PubMed
  • TnrA-GlnA, this interaction results in loss of TnrA DNA-binding activity PubMed

• Localization: membrane-associated via NrgA-NrgB under conditions of poor nitrogen supply PubMed

Database entries

• Structure:

• UniProt: Q45666

• KEGG entry: [3]

• E.C. number:

Expression and regulation

• Operon: tnrA (according to DBTBS)

• Expression browser: tnrA PubMed

• Sigma factor:

• Regulation:
  • expression is autocativated (TnrA) and repressed by GlnR PubMed
  • expressed in the absence of good nitrogen sources (glutamine or ammonium) (TnrA) PubMed

• Regulatory mechanism:
  • TnrA: transcription activation PubMed

• Additional information:

Biological materials

• Mutant: GP252 (in frame deletion), available in the Stülke lab
  • 1A851 ( tnrA::erm), PubMed, available at BGSC
  • 1A851 ( tnrA::erm), PubMed, available at BGSC

• Expression vector:
  • for expression, purification in E. coli with N-terminal His-tag, in pWH844: pGP171 available in Stülke lab
  • pGP229 (N-terminal Strep-tag, for SPINE, expression in B. subtilis, in pGP380), available in Stülke lab

• lacZ fusion:

• GFP fusion:

• two-hybrid system:

• Antibody: available in the Karl Forchhammer lab

Labs working on this gene/protein

Susan Fisher, Boston, USA homepage

References

Reviews

Katrin Gunka, Fabian M Commichau
Control of glutamate homeostasis in Bacillus subtilis: a complex interplay between ammonium assimilation, glutamate biosynthesis and degradation.
Mol Microbiol: 2012, 85(2);213-24
[PubMed:22625175] [WorldCat.org] [DOI] (I p)

Fabian M Commichau, Jörg Stülke
Trigger enzymes: bifunctional proteins active in metabolism and in controlling gene expression.
Mol Microbiol: 2008, 67(4);692-702
[PubMed:18086213] [WorldCat.org] [DOI] (P p)

S H Fisher
Regulation of nitrogen metabolism in Bacillus subtilis: vive la différence!
Mol Microbiol: 1999, 32(2);223-32
[PubMed:10231480] [WorldCat.org] [DOI] (P p)