DnaN

• Description: DNA polymerase III (beta subunit), beta clamp, part of the replisome, also involved in DNA mismatch repair, inhibitor of DnaA oligomerization
  
  

Gene name	dnaN
Synonyms	dnaG, dnaK
Essential	yes PubMed
Product	DNA polymerase III (beta subunit), beta clamp
Function	DNA replication, DNA repair
Gene expression levels in SubtiExpress: DnaN
Interactions involving this protein in SubtInteract: DnaN
MW, pI	41 kDa, 4.718
Gene length, protein length	1134 bp, 378 aa
Immediate neighbours	dnaA, yaaA
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

DNA replication, essential genes

This gene is a member of the following regulons

Spo0A regulon

The gene

Basic information

• Locus tag: BSU00020

Phenotypes of a mutant

essential PubMed

Database entries

• BsubCyc: BSU00020

• DBTBS entry: [1]

• SubtiList entry: [2]

The protein

Basic information/ Evolution

• Catalyzed reaction/ biological activity:
  • DnaN overexpression or release from the replisome decreases association of YabA with oriC, increases association of DnaA with oriC PubMed
  • Deoxynucleoside triphosphate + DNA(n) = diphosphate + DNA(n+1) (according to Swiss-Prot)
  • recruits MutS to the site of DNA replication (replisome) PubMed
  • required for bacteriophage SPP1 replication PubMed
  • inhibits oligomerization and helix formation of DnaA PubMed

• Protein family:

• Paralogous protein(s):

Extended information on the protein

• Kinetic information:

• Domains:

• Modification:

• Cofactor(s):

• Effectors of protein activity:

• Interactions:
  • DnaA-YabA-DnaN PubMed
  • part of the replisome: PolC-HolA-HolB-DnaX-DnaN-DnaG-DnaC-DnaI-DnaD-SsbA-DnaE-PriA-DnaB PubMed
  • PolY1-DnaN, PolY2-DnaN (required for untargeted mutagenesis) PubMed
  • PolY1-PolA-DnaN PubMed
  • MutL (C-terminal domain)-DnaN PubMed
  • MutS-DnaN PubMed
  • DnaE-DnaN PubMed
  • DnaN forms dimers PubMed

• Localization:
  • nucleoid (mid-cell spot) PubMed PubMed
  • forms large assemblies on DNA, called "clamp zones" PubMed
  • forms foci PubMed

Database entries

• BsubCyc: BSU00020

• Structure:

• UniProt: P05649

• KEGG entry: [3]

• E.C. number: 2.7.7.7

Expression and regulation

• Operon: dnaA-dnaN PubMed

• Expression browser: dnaN PubMed

• Sigma factor: SigA PubMed

• Regulation: negatively controlled by DnaA PubMed and Spo0A PubMed
  • repressed under conditions that trigger sporulation (Spo0A) PubMed

• Regulatory mechanism:
  • Spo0A: transcription repression PubMed

• Additional information:
  • number of protein molecules per cell (minimal medium with glucose and ammonium): 376 PubMed
  • number of protein molecules per cell (complex medium with amino acids, without glucose): 2265 PubMed

Biological materials

• Mutant:

• Expression vector:

• lacZ fusion:

• GFP fusion: PubMed PubMed

• two-hybrid system: B. pertussis adenylate cyclase-based bacterial two hybrid system (BACTH), available in Fabian Commichau's lab

• Antibody:

Labs working on this gene/protein

Philippe Noirot, Jouy-en-Josas, France homepage