Replication initiation at the Escherichia coli chromosomal origin

Curr Opin Chem Biol. 2011 Oct;15(5):606-13. doi: 10.1016/j.cbpa.2011.07.016. Epub 2011 Aug 18.

Abstract

To initiate DNA replication, DnaA recognizes and binds to specific sequences within the Escherichia coli chromosomal origin (oriC), and then unwinds a region within oriC. Next, DnaA interacts with DnaB helicase in loading the DnaB-DnaC complex on each separated strand. Primer formation by primase (DnaG) induces the dissociation of DnaC from DnaB, which involves the hydrolysis of ATP bound to DnaC. Recent evidence indicates that DnaC acts as a checkpoint in the transition from initiation to the elongation stage of DNA replication. Freed from DnaC, DnaB helicase unwinds the parental duplex DNA while interacting the cellular replicase, DNA polymerase III holoenzyme, and primase as it intermittently forms primers that are extended by the replicase in duplicating the chromosome.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Chromosomes, Bacterial / chemistry*
  • Chromosomes, Bacterial / genetics
  • DNA Polymerase III / genetics
  • DNA Polymerase III / metabolism*
  • DNA Primase / genetics
  • DNA Primase / metabolism*
  • DNA Replication*
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • DnaB Helicases / genetics
  • DnaB Helicases / metabolism*
  • Escherichia coli / genetics
  • Escherichia coli / metabolism*
  • Escherichia coli Proteins / genetics
  • Escherichia coli Proteins / metabolism*
  • Hydrolysis
  • Kinetics
  • Protein Binding / genetics
  • Replication Origin / genetics

Substances

  • Bacterial Proteins
  • DNA-Binding Proteins
  • DnaA protein, Bacteria
  • DnaC protein, E coli
  • Escherichia coli Proteins
  • DNA Primase
  • DNA Polymerase III
  • dnaB protein, E coli
  • DnaB Helicases