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: gltB
MW, pI	54.6 kDa, 7.69
Gene length, protein length	1479 bp, 493 amino acids
Immediate neighbours	yogA, gltA
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

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

• BsubCyc: BSU18440

• 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

• BsubCyc: BSU18440

• 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:
  • number of protein molecules per cell (minimal medium with glucose and ammonium): 1128 PubMed

Biological materials

• Mutant:
  • GP807 (del gltA-gltB::tet) , available in Jörg Stülke's lab
  • GP517 (ermC), available in Jörg Stülke's lab

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

• lacZ fusion: see gltA

• GFP fusion:

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