RocG

• Description: trigger enzyme: catabolic glutamate dehydrogenase induced by arginine, ornithine or proline, subject to carbon catabolite repression
  
  

Gene name	rocG
Synonyms
Essential	no
Product	trigger enzyme: glutamate dehydrogenase (major)
Function	arginine utilization, controls the activity of GltC
Metabolic function and regulation of this protein in SubtiPathways: Ammonium/ glutamate
MW, pI	46.2 kDa, 6.28
Gene length, protein length	1272 bp, 424 amino acids
Immediate neighbours	yweA, rocA
Get the DNA and protein sequences (Barbe et al., 2009)
Genetic context This image was kindly provided by SubtiList

The gene

Basic information

• Locus tag: BSU37790

Phenotypes of a mutant

Poor growth on complex media such as SP (sporulation medium). No growth in minimal media with arginine as the only carbon source. Rapid accumulation of suppressor mutants (gudB1)

Database entries

• DBTBS entry: [1]

• SubtiList entry: [2]

The protein

Basic information/ Evolution

• Catalyzed reaction/ biological activity: L-glutamate + H₂O + NAD⁺ = 2-oxoglutarate + NH₃ + NADH (according to Swiss-Prot) L-glutamate + H(2)O + NAD(+) = 2-oxoglutarate + NH(3) + NADH, controls the activity of the GltC transcription activator PubMed

• Protein family: Glu/Leu/Phe/Val dehydrogenases family (according to Swiss-Prot) Glu/Leu/Phe/Val dehydrogenases family

• Paralogous protein(s): GudB

Extended information on the protein

• Kinetic information:

• Domains:

• Modification:

• Cofactor(s):

• Effectors of protein activity:

• Interactions: RocG-GltC, this interaction prevents transcription activation of the gltA-gltB operon by GltC PubMed

• Localization:

Database entries

• Structure: 3K92 (super-repressor mutant that is capable of constitutive inactivation of GltC, E93K mutation)

• UniProt: P39633

• KEGG entry: [3]

• E.C. number: 1.4.1.2 1.4.1.2]

Expression and regulation

• Operon: rocG

• Sigma factor: SigL PubMed

• Regulation: induced by arginine (RocR, AhrC), ornithine or proline, subject to carbon catabolite repression (CcpA)

• Regulatory mechanism: RocR: transcription activation PubMedPubMed; AhrC: transcription activation ; CcpA: transcription repression

• Additional information:

Activation by RocR requires binding of RocG to a downstream element PubMed

Biological materials

• Mutant: GP747 (spc), GP726 (aphA3), GP810 (tet) available in Stülke lab

• Expression vector:
  • expression of native rocG in B. subtilis: pGP529 (in pBQ200), available in Stülke lab
  • for purification of RocG carrying an N-terminal Strep-tag: pGP902 (in pGP172), a series of rocG variants is also available in pGP172, available in Stülke lab

• lacZ fusion:

• GFP fusion:

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

• Antibody: available in Stülke lab

Labs working on this gene/protein

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

Jörg Stülke, University of Göttingen, Germany Homepage

References

Enzymatic activity of RocG

Function in the control of GltC activity

Christina Herzberg, Lope Andrés Flórez Weidinger, Bastian Dörrbecker, Sebastian Hübner, Jörg Stülke, Fabian M Commichau
SPINE: a method for the rapid detection and analysis of protein-protein interactions in vivo.
Proteomics: 2007, 7(22);4032-5
[PubMed:17994626] [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)

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)

Expression of rocG

Boris R Belitsky, Hyun-Jin Kim, Abraham L Sonenshein
CcpA-dependent regulation of Bacillus subtilis glutamate dehydrogenase gene expression.
J Bacteriol: 2004, 186(11);3392-8
[PubMed:15150224] [WorldCat.org] [DOI] (P p)

Naima Ould Ali, Josette Jeusset, Eric Larquet, Eric Le Cam, Boris Belitsky, Abraham L Sonenshein, Tarek Msadek, Michel Débarbouillé
Specificity of the interaction of RocR with the rocG-rocA intergenic region in Bacillus subtilis.
Microbiology (Reading): 2003, 149(Pt 3);739-750
[PubMed:12634342] [WorldCat.org] [DOI] (P p)

B R Belitsky, A L Sonenshein
An enhancer element located downstream of the major glutamate dehydrogenase gene of Bacillus subtilis.
Proc Natl Acad Sci U S A: 1999, 96(18);10290-5
[PubMed:10468601] [WorldCat.org] [DOI] (P p)

B R Belitsky, A L Sonenshein
Role and regulation of Bacillus subtilis glutamate dehydrogenase genes.
J Bacteriol: 1998, 180(23);6298-305
[PubMed:9829940] [WorldCat.org] [DOI] (P p)

Structural analysis of glutamate dehydrogenase

T J Stillman, P J Baker, K L Britton, D W Rice
Conformational flexibility in glutamate dehydrogenase. Role of water in substrate recognition and catalysis.
J Mol Biol: 1993, 234(4);1131-9
[PubMed:8263917] [WorldCat.org] [DOI] (P p)