DnaA
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dnaA is an replication initiation factor which promotes the unwinding or denaturation of DNA at oriC, during DNA replication in prokaryotes.
The oriC/dnaA complex formation and DNA unwinding do not require ATP hydrolysis.
Several dnaA molecules bind to the 9mer region of oriC, and unwind the DNA at the 13mer region (DUE´s elements). After initiation, dnaB along with dnaC bind to the melted 13mer region.
The melted 13mer allows the recuitment of DnaB (helicase)and DnaC (helicase loader)complex to the melted ssDNA. The DnaC is also complexed with ATP where it is hydrolyzed and released to allow DnaB to bind to ssDNA (the release of DnaC from the DnaC-DnaB complex is required for DnaB to bind to ssDNA). The DnaB is a 5'->3' helicase, so it travels on the lagging strand. It associates with DnaG (primase) occasionally to add RNA primers on the lagging strand. The interaction between DnaG and DnaB is necessary to control the longitude of Okazaki fragments on the lagging strand