GapB

• Description: glyceraldehyde-3-phosphate dehydrogenase, NADP-dependent, gluconeogenic enzyme, forms a transhydrogenation cycle with GapA for balancing of NADPH
  
  

Gene name	gapB
Synonyms	ppc
Essential	no
Product	glyceraldehyde-3-phosphate dehydrogenase 2
Function	anabolic enzyme in gluconeogenesis
Gene expression levels in SubtiExpress: gapB
Metabolic function and regulation of this protein in SubtiPathways: gapB
MW, pI	37,3 kDa, 6.47
Gene length, protein length	1020 bp, 340 amino acids
Immediate neighbours	speD, ytcD
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

carbon core metabolism

This gene is a member of the following regulons

CcpN regulon

The gene

Basic information

• Locus tag: BSU29020

Database entries

• DBTBS entry: [1]

• SubtiList entry: [2]

The protein

Basic information/ Evolution

• Catalyzed reaction/ biological activity: D-glyceraldehyde 3-phosphate + phosphate + NAD(P)⁺ = 3-phospho-D-glyceroyl phosphate + NAD(P)H (according to Swiss-Prot)
  • This reaction is part of the gluconeogenesis

• Protein family: glyceraldehyde-3-phosphate dehydrogenase family (according to Swiss-Prot)

• Paralogous protein(s): GapA

Extended information on the protein

• Kinetic information: Michaelis-Menten PubMed

• Domains:
  • Nucleotid bindinge domain (12-13)
  • 2x Glyceraldehyde 3-phosphate binding domain (151-153) & (210-211)

• Modification:

• Cofactor(s): NADP⁺ (preferentially) and NAD⁺ PubMed

• Effectors of protein activity:

• Interactions:

• Localization: Cytoplasm (Homogeneous) PubMed

Database entries

• Structure: 3PRL (from B. halodurans)

• UniProt: O34425

• KEGG entry: [3]

• E.C. number: 1.2.1.59

Expression and regulation

• Operon: gapB-speD PubMed

• Expression browser: gapB PubMed

• Sigma factor: SigA PubMed

• Regulation:
  • repressed in the presence of glucose (70-fold) (CcpN) PubMed
  • strongly induced in response to glucose starvation in M9 medium PubMed

• Regulatory mechanism:
  • CcpN: transcription repression PubMed

• Additional information:

Biological materials

• Mutant:
  • GP701 (gapB::spec), available in Stülke lab
  • 1A1004 ( gapB::erm), PubMed, available at BGSC

• Expression vector:

• lacZ fusion:

• GFP fusion:

• Antibody:

Labs working on this gene/protein

Stephane Aymerich, Microbiology and Molecular Genetics, INRA Paris-Grignon, France