PtsG

• Description: trigger enzyme: major glucose permease of the PTS, EIICBA(Glc) and control of GlcT activity
  
  

Gene name	ptsG
Synonyms	ptsX, crr
Essential	no
Product	trigger enzyme: glucose-specific enzyme IICBA component of the PTS
Function	glucose transport and phosphorylation, control of GlcT activity
Gene expression levels in SubtiExpress: ptsG
Interactions involving this protein in SubtInteract: PtsG
Metabolic function and regulation of this protein in SubtiPathways: Central C-metabolism, Sugar catabolism
MW, pI	75,3 kDa, 5.40
Gene length, protein length	2097 bp, 699 amino acids
Immediate neighbours	glcT, ptsH
Sequences	Protein DNA Advanced_DNA
Genetic context This image was kindly provided by SubtiList
Expression at a glance   PubMed

Categories containing this gene/protein

phosphotransferase systems, carbon core metabolism, transcription factors and their control, trigger enzyme, membrane proteins, phosphoproteins

This gene is a member of the following regulons

GlcT regulon, stringent response

The gene

Basic information

• Locus tag: BSU13890

Database entries

• DBTBS entry: [1]

• SubtiList entry: [2]

The protein

Basic information/ Evolution

• Catalyzed reaction/ biological activity: transport and phosphorylation of glucose, receives a phosphate from HPr at the IIA domain (His-620), the phosphate group is then transferred to the IIB domain (Cys-461) an finally to the incoming glucose. In the absence of glucose, PtsG phosphorylates and thereby inactivates the transcriptional antiterminator GlcT.

• Protein family: PTS permease, glucose permease (Glc) family PubMed, PTS enzyme II

• Paralogous protein(s):

Extended information on the protein

• Kinetic information:

• Domains:
  • 11x transmembrane domain (16–36, 89–109, 139–159, 180–200, 233–253, 283–303, 313–333, 338–358, 365–385, 388–408)
  • PTS EIIC domain ( 1-424)
  • PTS EIIB domain (439–520)
  • PTS EIIA domain (568–672)

• Modification: transient phosphorylation (HPr-dependent) on His-620, then internal phosphotransfer from His-620 to Cys-461

• Cofactor(s):

• Effectors of protein activity:

• Interactions:
  • HPr-PtsG PubMed
  • PtsG-GlcT (for phosphorylation of GlcT) PubMed

• Localization: membrane protein PubMed

Database entries

• Structure: 1AX3 (IIA domain), 1GPR (IIA domain), IIA domain NCBI, NMR IIA domain NCBI

• UniProt: P20166

• KEGG entry: [3]

• E.C. number: 2.7.1.69

Expression and regulation

• Operon: ptsG-ptsH-ptsI PubMed

• Expression browser: ptsG PubMed

• Sigma factor: SigA PubMed

• Regulation:
  • expression activated by glucose (32 fold) (GlcT) PubMed
  • subject to negative stringent control upon lysine starvation PubMed

• Regulatory mechanism:
  • transcriptional antitermination via the GlcT-dependent RNA switch PubMed
  • stringent response: due to presence of guanine at +1 position of the transcript PubMed

• Additional information:

Biological materials

• Mutants: all available in Stülke lab
  • QB5435 (cat)
  • QB5436 (spc)
  • QB5445 (erm)
  • GP778 (replacement of glcT and the ptsG-ptsH-ptsI operon by a spc cassette)
  • GP926 (substitution of glcT and ptsG by a tet cassette)

• Expression vector:
  • pGP123 (domains BA, in pWH844), available in Stülke lab
  • pGP141 (domains BA, mut: H620D, in pWH844), available in Stülke lab
  • pGP428 (EIIB, in pWH844), available in Stülke lab
  • pGP437(EIIA in pGP570, with thrombin cleavage site), available in Stülke lab

• lacZ fusion:
  • pGP34 (pAC5), available in Stülke lab
  • pGP66 (pAC7), available in Stülke lab
  • pGP606 (mutant terminator, pAC6), available in Stülke lab
  • pGP532 (pAC7), available in Stülke lab
  • series of promoter deletions are available in pAC5 and pAC6, available in Stülke lab
  • series of RAT mutants are available in pAC6, available in Stülke lab

• GFP fusion:

• Antibody:

Labs working on this gene/protein

Jörg Stülke, University of Göttingen, Germany Homepage

References

Reviews

Fabian M Commichau, Jörg Stülke
Trigger enzymes: bifunctional proteins active in metabolism and in controlling gene expression.
Mol Microbiol: 2008, 67(4);692-702
[PubMed:18086213] [WorldCat.org] [DOI] (P p)