IlvB

• Description: acetolactate synthase (large subunit)
  
  

Gene name	ilvB
Synonyms
Essential	no
Product	acetolactate synthase (large subunit)
Function	biosynthesis of branched-chain amino acids
Gene expression levels in SubtiExpress: ilvB
Metabolic function and regulation of this protein in SubtiPathways: Ile, Leu, Val, Coenzyme A
MW, pI	62 kDa, 5.178
Gene length, protein length	1722 bp, 574 aa
Immediate neighbours	ilvH, ysnD
Sequences	Protein DNA DNA_with_flanks
Genetic context This image was kindly provided by SubtiList
Expression at a glance   PubMed

The gene

Basic information

• Locus tag: BSU28310

Database entries

• DBTBS entry: [1]

• SubtiList entry: [2]

Categories containing this gene/protein

biosynthesis/ acquisition of amino acids, phosphoproteins

This gene is a member of the following regulons

CodY regulon, CcpA regulon, TnrA regulon, T-box

The protein

Basic information/ Evolution

• Catalyzed reaction/ biological activity: 2 pyruvate = 2-acetolactate + CO₂ (according to Swiss-Prot)

• Protein family: TPP enzyme family (according to Swiss-Prot)

• Paralogous protein(s): AlsS, YdaP

Extended information on the protein

• Kinetic information:

• Domains:

• Modification:
  • phosphorylated on Arg-297 PubMed

• Cofactors:

• Effectors of protein activity:

• Interactions:

• Localization:

Database entries

• Structure: 1N53 (T box RNA)

• UniProt: P37251

• KEGG entry: [3]

• E.C. number: 2.2.1.6

Additional information

• subject to Clp-dependent proteolysis upon glucose starvation PubMed

Expression and regulation

• Operon: ilvB-ilvH-ilvC-leuA-leuB-leuC-leuD PubMed

• Expression browser: ilvB PubMed

• Sigma factor: SigA PubMed

• Regulation:
  • for a complete overview on the regulation of the ilv operon, see Brinsmade et al.
  • expression is stimulated in the presence of glucose (CcpA) PubMed
  • repressed under nitrogen limiting conditions (glutamine or ammonium) (TnrA) PubMed
  • repressed by casamino acids PubMed
  • repressed during growth in the presence of branched chain amino acids (CodY) PubMed

• Regulatory mechanism:
  • CcpA: transcription activation PubMed
  • repression by BCAA: tRNA-controlled RNA switch (T-box) that mediates termination/antitermination
  • TnrA: transcription repression PubMed
  • CodY: transcription repression PubMed1 PubMed2

• Additional information: subject to Clp-dependent proteolysis upon glucose starvation PubMed

Biological materials

• Mutant: GP324, ilvB under control of pXyl (cat), available in Jörg Stülke's lab

• Expression vector:

• lacZ fusion: pGP520 and pGP524 (both in pAC5), pGP523 (in pAC6), all are available in Jörg Stülke's lab

• GFP fusion:

• two-hybrid system:

• Antibody: