PtsI

• Description: Enzyme I, general (non sugar-specific) component of the PTS. Enzyme I transfers the phosphoryl group from phosphoenolpyruvate (PEP) to the phosphoryl carrier protein (HPr)
  
  

Gene name	ptsI
Synonyms
Essential	no
Product	phosphotransferase system (PTS) enzyme I
Function	PTS-dependent sugar transport
Gene expression levels in SubtiExpress: ptsI
Interactions involving this protein in SubtInteract: PtsI
Metabolic function and regulation of this protein in SubtiPathways: ptsI
MW, pI	62,9 kDa, 4.59
Gene length, protein length	1710 bp, 570 amino acids
Immediate neighbours	ptsH, splA
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

phosphotransferase systems, phosphoproteins, most abundant proteins

This gene is a member of the following regulons

GlcT regulon, stringent response

The gene

Basic information

• Locus tag: BSU13910

Database entries

• BsubCyc: BSU13910

• DBTBS entry: [1]

• SubtiList entry: [2]

The protein

Basic information/ Evolution

• Catalyzed reaction/ biological activity: Phosphoenolpyruvate + protein L-histidine = pyruvate + protein N(pi)-phospho-L-histidine (according to Swiss-Prot) PEP-dependent autophosphorylation on His-189, transfer of the phosphoryl group to HPr (His-15)

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

• Paralogous protein(s):

Extended information on the protein

• Kinetic information:

• Domains:
  • HPr binding site (N-Terminal Domain)
  • pyruvate binding site (C-Terminal Domain)
  • pyrophosphate/phosphate carrier histidine (central Domain)

• Modification:
  • transient autophosphorylation on His-189
  • in vivo also phosphorylated on Ser-34 or Ser-36 PubMed

• Cofactors: Magnesium

• Effectors of protein activity:

• Interactions:
  • PtsI-PtsH

• Localization:
  • cytoplasm, even distribution PubMed

Database entries

• BsubCyc: BSU13910

• Structure: 2WQD (Enzyme I from Staphylococcus aureus) PubMed

• UniProt: P08838

• KEGG entry: [3]

• E.C. number: 2.7.3.9 2.7.3.9]

Expression and regulation

• Operon:
  • ptsG-ptsH-ptsI PubMed
  • ptsH-ptsI PubMed

• Expression browser: ptsI PubMed

• Sigma factor:
  • ptsG: SigA PubMed
  • ptsH: SigA PubMed

• Regulation:
  • expression activated by glucose (2 fold) (GlcT) PubMed
  • the ptsH promoter is constitutive PubMed
  • subject to negative stringent control upon amino acid limitation (due to control of ptsG transcription initiation) PubMed

• Regulatory mechanism:
  • ptsG: transcriptional antitermination via the GlcT-dependent RNA switch PubMed

• Additional information:
  • belongs to the 100 most abundant proteins PubMed
  • number of protein molecules per cell (minimal medium with glucose and ammonium): 3157 PubMed
  • number of protein molecules per cell (complex medium with amino acids, without glucose): 4976 PubMed

Biological materials

• Mutant: available in Jörg Stülke's lab:
  • GP864 (ermC)
  • GP778 (replacement of glcT and the ptsG-ptsH-ptsI operon by a spc cassette), PubMed

• Expression vector:
  • pAG3 (His-tag) PubMed, available in Galinier lab
  • for expression, purification in E. coli (His-tag), in pWH844: pGP813 available in Jörg Stülke's lab

• lacZ fusion:

• GFP fusion:

• YFP fusion: B. subtilis GP1276 ptsI-yfp ermC, available in Jörg Stülke's lab

• Antibody:

Labs working on this gene/protein

Josef Deutscher, Paris-Grignon, France

Jörg Stülke, University of Göttingen, Germany Homepage