GapA

• Synonyms:

• Description: glyceraldehyde-3-phosphate dehydrogenase, (NADH-dependent), glycolytic enzyme

The gene

Basic information

• Coordinates:

• Gene length:

Phenotypes of a mutant

essential

Database entries

• DBTBS entry: [1]

• SubtiList entry:[2]

The protein

Basic information/ Evolution

• Catalyzed reaction/ biological activity: glyceraldehyde-3-phosphate dehydrogenase, (NADH-dependent). Catalyzes the reaction from glyceraldehyde-3-phosphate to 1.3-bi-phosphoglycerate. This reaction is part of the glycolysis.

• Protein family:

• Paralogous protein(s): GapB

Extended information on the protein

• Kinetic information: K(M) for NAD: 5.7 mM, K(cat) for NAD: 70/sec (determined for GapA from Geobacillus stearothermophilus)

• Domains:

• Modification: Phosphorylation (STY)

• Effectors of protein activity:

• Interactions:
  • GapA-PtsH: HPr(Ser-46-P) binds GapA resulting in a slight inhibition of enzymatic activity.
  • GapA-Crh: Crh(Ser-46-P) binds GapA resulting in a slight inhibition of enzymatic activity.

• Localization: membrane and cytoplasm

Database entries

• Structure:
  • 3CMC (from Geobacillus stearothermophilus)
  • 1NQO (from Geobacillus stearothermophilus, mutant with cys 149 replaced by ser, complex with NAD+ und D-Glyceraldehyde-3-Phosphate)

• Swiss prot entry: P09124

• KEGG entry: KEGG

• E.C. number: 1.2.1.12

Expression and regulation

• Operon:
  • cggR-gapA-pgk-tpiA-pgm-eno
  • cggR-gapA

The primary mRNAs of the operon are highly unstable. The primary mRNA is subject to processing at the very end of the cggR open reading frame. This results in stable mature gapA and gapA-pgk-tpiA-pgm-eno mRNAs. The processing event requires the Rny protein.

• Sigma factor: SigA

• Regulation: CggR represses the operon in the absence of glycolytic sugars

• Regulatory mechanism: repression

• Database entries: DBTBS

• Additional information: GapA is one of the most abundant proteins in the cell. In the presence of glucose, there are about 25,000 GapA molecules per cell.

Biological materials

• Mutant:

• Expression vector: pGP90 (N-terminal Strep-tag, purification from B. subtilis), pGP704 (N-terminal His-tag) (available in Stülke lab)

• lacZ fusion: pGP506 (in pAC7), pGP512 (in pAC6) (available in Stülke lab)

• GFP fusion:

• Antibody: available in Stülke lab

Labs working on this gene/protein

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

Jörg Stülke, University of Göttingen, Germany [3]

References

1. Author1, Author2 & Author3 (year) Title Journal volume: page-page. [4]