DnaB Helicase - E. Coli DnaB

E. Coli DnaB

In E. coli, dnaB is a hexameric protein of six 471 residue subunits, which form a ring-shaped structure with threefold symmetry. During DNA replication, the lagging strand of DNA binds in the central channel of dnaB, and the second DNA strand is excluded. The binding of dNTPs causes a conformational change which allows the dnaB to translocate along the DNA, thus mechanically forcing the separation of the DNA strands.