GltB

• Description: small subunit of glutamate synthase
  
  

Gene name	gltB
Synonyms
Essential	no
Product	glutamate synthase (small subunit)
Function	glutamate biosynthesis
Gene expression levels in SubtiExpress: gltB
Interactions involving this protein in SubtInteract: GltB
Metabolic function and regulation of this protein in SubtiPathways: Ammonium/ glutamate
MW, pI	54.6 kDa, 7.69
Gene length, protein length	1479 bp, 493 amino acids
Immediate neighbours	yogA, gltA
Sequences	Protein DNA Advanced_DNA
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

This gene is a member of the following regulons

GltC regulon, FsrA regulon, TnrA regulon

The gene

Basic information

• Locus tag: BSU18440

Phenotypes of a mutant

auxotrophic for glutamate

Database entries

• DBTBS entry: [1]

• SubtiList entry:[2]

The protein

Basic information/ Evolution

• Catalyzed reaction/ biological activity: 2 L-glutamate + NADP⁺ = L-glutamine + 2-oxoglutarate + NADPH (according to Swiss-Prot) 2 L-glutamate + NADP(+) <=> L-glutamine + 2-oxoglutarate + NADPH

• Protein family: glutamate synthase family.

• Paralogous protein(s): none

Extended information on the protein

• Kinetic information:

• Domains:
  • nucleotide binding domain (NADP) (299–313)

• Modification:

• Cofactor(s):

• Effectors of protein activity:

• Interactions:
  • GltA-GltB PubMed

• Localization: cytoplasm (according to Swiss-Prot)

Database entries

• Structure: 2VDC (the GltA-GltB complex of Azospirillum brasiliense) PubMed

• UniProt: O34399

• KEGG entry: [3]

• E.C. number: 1.4.1.13

Expression and regulation

• Operon: gltA-gltB PubMed

• Expression browser: gltB PubMed

• Sigma factor: SigA PubMed

• Regulation: see gltA

• Additional information:

Biological materials

• Mutant: GP807 (del gltAB::tet), GP517 (ermC), both available in Stülke lab

• Expression vector:
  • pGP1119 (in pGP380, for SPINE, expression in B. subtilis), available in Stülke lab

• lacZ fusion: see gltA

• GFP fusion:

• two-hybrid system: B. pertussis adenylate cyclase-based bacterial two hybrid system (BACTH), available in Stülke lab

• Antibody:

Labs working on this gene/protein

Linc Sonenshein, Tufts University, Boston, MA, USA Homepage

Jörg Stülke, University of Göttingen, Germany Homepage

Fabian Commichau University of Göttingen, Germany 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)

Akira Suzuki, David B Knaff
Glutamate synthase: structural, mechanistic and regulatory properties, and role in the amino acid metabolism.
Photosynth Res: 2005, 83(2);191-217
[PubMed:16143852] [WorldCat.org] [DOI] (P p)

Frank M Raushel, James B Thoden, Hazel M Holden
Enzymes with molecular tunnels.
Acc Chem Res: 2003, 36(7);539-48
[PubMed:12859215] [WorldCat.org] [DOI] (P p)

Original publications

Gregory T Smaldone, Olga Revelles, Ahmed Gaballa, Uwe Sauer, Haike Antelmann, John D Helmann
A global investigation of the Bacillus subtilis iron-sparing response identifies major changes in metabolism.
J Bacteriol: 2012, 194(10);2594-605
[PubMed:22389480] [WorldCat.org] [DOI] (I p)

Frederik M Meyer, Jan Gerwig, Elke Hammer, Christina Herzberg, Fabian M Commichau, Uwe Völker, Jörg Stülke
Physical interactions between tricarboxylic acid cycle enzymes in Bacillus subtilis: evidence for a metabolon.
Metab Eng: 2011, 13(1);18-27
[PubMed:20933603] [WorldCat.org] [DOI] (I p)

Fabian M Commichau, Katrin Gunka, Jens J Landmann, Jörg Stülke
Glutamate metabolism in Bacillus subtilis: gene expression and enzyme activities evolved to avoid futile cycles and to allow rapid responses to perturbations of the system.
J Bacteriol: 2008, 190(10);3557-64
[PubMed:18326565] [WorldCat.org] [DOI] (I p)

Magali Cottevieille, Eric Larquet, Slavica Jonic, Maxim V Petoukhov, Gianluca Caprini, Stefano Paravisi, Dmitri I Svergun, Maria A Vanoni, Nicolas Boisset
The subnanometer resolution structure of the glutamate synthase 1.2-MDa hexamer by cryoelectron microscopy and its oligomerization behavior in solution: functional implications.
J Biol Chem: 2008, 283(13);8237-49
[PubMed:18199747] [WorldCat.org] [DOI] (P p)

Fabian M Commichau, Christina Herzberg, Philipp Tripal, Oliver Valerius, Jörg Stülke
A regulatory protein-protein interaction governs glutamate biosynthesis in Bacillus subtilis: the glutamate dehydrogenase RocG moonlights in controlling the transcription factor GltC.
Mol Microbiol: 2007, 65(3);642-54
[PubMed:17608797] [WorldCat.org] [DOI] (P p)

Fabian M Commichau, Ingrid Wacker, Jan Schleider, Hans-Matti Blencke, Irene Reif, Philipp Tripal, Jörg Stülke
Characterization of Bacillus subtilis mutants with carbon source-independent glutamate biosynthesis.
J Mol Microbiol Biotechnol: 2007, 12(1-2);106-13
[PubMed:17183217] [WorldCat.org] [DOI] (P p)

Silvia Picossi, Boris R Belitsky, Abraham L Sonenshein
Molecular mechanism of the regulation of Bacillus subtilis gltAB expression by GltC.
J Mol Biol: 2007, 365(5);1298-313
[PubMed:17134717] [WorldCat.org] [DOI] (P p)

Boris R Belitsky, Abraham L Sonenshein
Modulation of activity of Bacillus subtilis regulatory proteins GltC and TnrA by glutamate dehydrogenase.
J Bacteriol: 2004, 186(11);3399-407
[PubMed:15150225] [WorldCat.org] [DOI] (P p)

Ingrid Wacker, Holger Ludwig, Irene Reif, Hans-Matti Blencke, Christian Detsch, Jörg Stülke
The regulatory link between carbon and nitrogen metabolism in Bacillus subtilis: regulation of the gltAB operon by the catabolite control protein CcpA.
Microbiology (Reading): 2003, 149(Pt 10);3001-3009
[PubMed:14523131] [WorldCat.org] [DOI] (P p)

Ken-ichi Yoshida, Hirotake Yamaguchi, Masaki Kinehara, Yo-hei Ohki, Yoshiko Nakaura, Yasutaro Fujita
Identification of additional TnrA-regulated genes of Bacillus subtilis associated with a TnrA box.
Mol Microbiol: 2003, 49(1);157-65
[PubMed:12823818] [WorldCat.org] [DOI] (P p)

B R Belitsky, L V Wray, S H Fisher, D E Bohannon, A L Sonenshein
Role of TnrA in nitrogen source-dependent repression of Bacillus subtilis glutamate synthase gene expression.
J Bacteriol: 2000, 182(21);5939-47
[PubMed:11029411] [WorldCat.org] [DOI] (P p)

B R Belitsky, A L Sonenshein
Mutations in GltC that increase Bacillus subtilis gltA expression.
J Bacteriol: 1995, 177(19);5696-700
[PubMed:7559360] [WorldCat.org] [DOI] (P p)

D E Bohannon, A L Sonenshein
Positive regulation of glutamate biosynthesis in Bacillus subtilis.
J Bacteriol: 1989, 171(9);4718-27
[PubMed:2548995] [WorldCat.org] [DOI] (P p)