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
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

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

References

Reviews

Gunka K, Commichau FM    
Control of glutamate homeostasis in Bacillus subtilis: 
a complex interplay between ammonium assimilation,  
glutamate biosynthesis and degradation.  
Mol Microbiol.: 2012, 85(2) 213-224. 
PubMed:22625175

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)