GlnA

• Description: trigger enzyme: glutamine synthetase and effector of TnrA and GlnR
  
  

Gene name	glnA
Synonyms
Essential	no
Product	trigger enzyme: glutamine synthetase
Function	glutamine biosynthesis, control of TnrA and GlnR activity
Gene expression levels in SubtiExpress: glnA
Interactions involving this protein in SubtInteract: GlnA
Metabolic function and regulation of this protein in SubtiPathways: Ammonium/ glutamate
MW, pI	50 kDa, 4.874
Gene length, protein length	1332 bp, 444 aa
Immediate neighbours	glnR, ynxB
Sequences	Protein DNA DNA_with_flanks
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, trigger enzyme, phosphoproteins

This gene is a member of the following regulons

GlnR regulon, TnrA regulon

The gene

Basic information

• Locus tag: BSU17460

Phenotypes of a mutant

auxotrophic for glutamine

Database entries

• DBTBS entry: [1]

• SubtiList entry: [2]

The protein

Basic information/ Evolution

• Catalyzed reaction/ biological activity: ATP + L-glutamate + NH₃ = ADP + phosphate + L-glutamine (according to Swiss-Prot)

• Protein family: glutamine synthetase family (according to Swiss-Prot)

• Paralogous protein(s):

Extended information on the protein

• Kinetic information: K(M) for: Glu: 27 mM, ATP: 2.4 mM, ammonium: 0.18 mM; v(max): 3.7 µmol/min/mg

• Domains: glutamate binding flap (aa 300 ... 306: protects unstable intermediates from abberant hydrolysis)

• Modification:
  • phosphorylated on ser/ thr/ tyr PubMed
  • in vitro phosphorylated by PrkC on Thr-26, Thr-147, Ser-207, and Thr-286 PubMed

• Cofactor(s): Mg(2+)

• Effectors of protein activity:
  • feedback inhibition by glutamine, glutamine binds the entrance site for glutamate
  • activity is inhibited upon interaction with TnrA PubMed

• Interactions:
  • TnrA-GlnA PubMed
  • GlnR-GlnA PubMed, (only the feedback-inhibited enzyme interacts with TnrA and GlnR)
  • GlnA-NrgB PubMed

• Localization: cytoplasm (according to Swiss-Prot)

Database entries

• Structure:
  • 3QAJ (complex with ATP)
  • A general discussion of GS structure

• UniProt: P12425

• KEGG entry: [3]

• E.C. number: 6.3.1.2

Additional information

GlnA is a homooligomer of 12 subunits

Expression and regulation

• Operon: glnR-glnA PubMed

• Expression browser: glnA PubMed

• Sigma factor: SigA PubMed

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

• Regulatory mechanism:
  • GlnR-GlnA complex: transcription repression PubMed
  • TnrA: transcription repression PubMed

• Additional information:

Biological materials

• Mutant: GP247 (glnA::cat), available in Stülke lab

• Expression vector:
  • expression/ purification from E. coli, with N-terminal Strep-tag (in pGP172): pGP174, available in Stülke lab
  • pGP177 (N-terminal Strep-tag, purification from B. subtilis, for SPINE, in pBQ200), available in Jörg Stülke's lab

• lacZ fusion: glnR-lacZ: pGP189 (in pAC7), available in Stülke lab

• GFP fusion:

• two-hybrid system:

• Antibody: available in 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)

Original publications

Ksenia Fedorova, Airat Kayumov, Kathrin Woyda, Olga Ilinskaja, Karl Forchhammer
Transcription factor TnrA inhibits the biosynthetic activity of glutamine synthetase in Bacillus subtilis.
FEBS Lett: 2013, 587(9);1293-8
[PubMed:23535029] [WorldCat.org] [DOI] (I p)

Airat Kayumov, Annette Heinrich, Kseniya Fedorova, Olga Ilinskaya, Karl Forchhammer
Interaction of the general transcription factor TnrA with the PII-like protein GlnK and glutamine synthetase in Bacillus subtilis.
FEBS J: 2011, 278(10);1779-89
[PubMed:21435182] [WorldCat.org] [DOI] (I p)

Lewis V Wray, Susan H Fisher
Functional roles of the conserved Glu304 loop of Bacillus subtilis glutamine synthetase.
J Bacteriol: 2010, 192(19);5018-25
[PubMed:20656908] [WorldCat.org] [DOI] (I p)

Nico Pietack, Dörte Becher, Sebastian R Schmidl, Milton H Saier, Michael Hecker, Fabian M Commichau, Jörg Stülke
In vitro phosphorylation of key metabolic enzymes from Bacillus subtilis: PrkC phosphorylates enzymes from different branches of basic metabolism.
J Mol Microbiol Biotechnol: 2010, 18(3);129-40
[PubMed:20389117] [WorldCat.org] [DOI] (I p)

Susan H Fisher, Lewis V Wray
Novel trans-Acting Bacillus subtilis glnA mutations that derepress glnRA expression.
J Bacteriol: 2009, 191(8);2485-92
[PubMed:19233925] [WorldCat.org] [DOI] (I p)

Lewis V Wray, Susan H Fisher
Bacillus subtilis GlnR contains an autoinhibitory C-terminal domain required for the interaction with glutamine synthetase.
Mol Microbiol: 2008, 68(2);277-85
[PubMed:18331450] [WorldCat.org] [DOI] (I p)

Susan H Fisher, Lewis V Wray
Bacillus subtilis glutamine synthetase regulates its own synthesis by acting as a chaperone to stabilize GlnR-DNA complexes.
Proc Natl Acad Sci U S A: 2008, 105(3);1014-9
[PubMed:18195355] [WorldCat.org] [DOI] (I p)

Susan H Fisher, Lewis V Wray
Feedback-resistant mutations in Bacillus subtilis glutamine synthetase are clustered in the active site.
J Bacteriol: 2006, 188(16);5966-74
[PubMed:16885465] [WorldCat.org] [DOI] (P p)

Jill M Zalieckas, Lewis V Wray, Susan H Fisher
Cross-regulation of the Bacillus subtilis glnRA and tnrA genes provides evidence for DNA binding site discrimination by GlnR and TnrA.
J Bacteriol: 2006, 188(7);2578-85
[PubMed:16547045] [WorldCat.org] [DOI] (P p)

Alain Lévine, Françoise Vannier, Cédric Absalon, Lauriane Kuhn, Peter Jackson, Elaine Scrivener, Valérie Labas, Joëlle Vinh, Patrick Courtney, Jérôme Garin, Simone J Séror
Analysis of the dynamic Bacillus subtilis Ser/Thr/Tyr phosphoproteome implicated in a wide variety of cellular processes.
Proteomics: 2006, 6(7);2157-73
[PubMed:16493705] [WorldCat.org] [DOI] (P p)

Lewis V Wray, Susan H Fisher
A feedback-resistant mutant of Bacillus subtilis glutamine synthetase with pleiotropic defects in nitrogen-regulated gene expression.
J Biol Chem: 2005, 280(39);33298-304
[PubMed:16055443] [WorldCat.org] [DOI] (P p)

Susan H Fisher, Jaclyn L Brandenburg, Lewis V Wray
Mutations in Bacillus subtilis glutamine synthetase that block its interaction with transcription factor TnrA.
Mol Microbiol: 2002, 45(3);627-35
[PubMed:12139611] [WorldCat.org] [DOI] (P p)

L V Wray, J M Zalieckas, S H Fisher
Bacillus subtilis glutamine synthetase controls gene expression through a protein-protein interaction with transcription factor TnrA.
Cell: 2001, 107(4);427-35
[PubMed:11719184] [WorldCat.org] [DOI] (P p)

L V Wray, A E Ferson, K Rohrer, S H Fisher
TnrA, a transcription factor required for global nitrogen regulation in Bacillus subtilis.
Proc Natl Acad Sci U S A: 1996, 93(17);8841-5
[PubMed:8799114] [WorldCat.org] [DOI] (P p)

S W Brown, A L Sonenshein
Autogenous regulation of the Bacillus subtilis glnRA operon.
J Bacteriol: 1996, 178(8);2450-4
[PubMed:8636055] [WorldCat.org] [DOI] (P p)

H J Schreier, C A Rostkowski, E M Kellner
Altered regulation of the glnRA operon in a Bacillus subtilis mutant that produces methionine sulfoximine-tolerant glutamine synthetase.
J Bacteriol: 1993, 175(3);892-7
[PubMed:8093698] [WorldCat.org] [DOI] (P p)

H J Schreier, S W Brown, K D Hirschi, J F Nomellini, A L Sonenshein
Regulation of Bacillus subtilis glutamine synthetase gene expression by the product of the glnR gene.
J Mol Biol: 1989, 210(1);51-63
[PubMed:2573733] [WorldCat.org] [DOI] (P p)

M A Strauch, A I Aronson, S W Brown, H J Schreier, A L Sonenhein
Sequence of the Bacillus subtilis glutamine synthetase gene region.
Gene: 1988, 71(2);257-65
[PubMed:2906311] [WorldCat.org] [DOI] (P p)

S H Fisher, A L Sonenshein
Bacillus subtilis glutamine synthetase mutants pleiotropically altered in glucose catabolite repression.
J Bacteriol: 1984, 157(2);612-21
[PubMed:6141156] [WorldCat.org] [DOI] (P p)