Initiation of DNA replication in prokaryotes involves loading and activation of DnaB helicase. DnaB helicase directs other necessary enzymes (particularly DnaG Primase and DNA pol III HE) to the template and help in DNA elongation. These aspects will be discussed below: DnaB protein DnaB is the major helicase, it unwinds the template in 5\'-3\' direction during oriC replication in vitro, at a rate of 700bp/sec. The direction of unwinding requires DnaB to be placed on lagging strand, ahead of the polymerase on the leading strand. It also activates primer synthesis by DnaG primase. DnaG primase The primase (DnaG) synthesizes a unique oligonucleotide primer on SSB coated single stranded phage G4 DNA. The sequence recognised by primase is over 100 nucleotides long containing a secondary structure. Since primer synthesis requires activation by DnaB, the latter is oftern described as a \'mobile promoter\' of primer synthesis. DNA polymerase III holoenzyme DNA polymerase III HE is the large multiprotein complex responsible for elongation of DNA replication in E. coli. It has atleast 10 subunits, each with specific function. Other proteins involved in DNA elongation are DNA gyrase (topoisomerase), which removes the topological strain associated with DNA unwinding SSB (single stranded DNA binding) protein, that binds tightly to single stranded DNA thus stabilizing the unwound DNA. RNase H removes RNA primers DNA Polymerase I is used for filling the gap created due to the removal of RNA primers DNA ligase converts the okasaki fragments into a continuous strand. Solution Initiation of DNA replication in prokaryotes involves loading and activation of DnaB helicase. DnaB helicase directs other necessary enzymes (particularly DnaG Primase and DNA pol III HE) to the template and help in DNA elongation. These aspects will be discussed below: DnaB protein DnaB is the major helicase, it unwinds the template in 5\'-3\' direction during oriC replication in vitro, at a rate of 700bp/sec. The direction of unwinding requires DnaB to be placed on lagging strand, ahead of the polymerase on the leading strand. It also activates primer synthesis by DnaG primase. DnaG primase The primase (DnaG) synthesizes a unique oligonucleotide primer on SSB coated single stranded phage G4 DNA. The sequence recognised by primase is over 100 nucleotides long containing a secondary structure. Since primer synthesis requires activation by DnaB, the latter is oftern described as a \'mobile promoter\' of primer synthesis. DNA polymerase III holoenzyme DNA polymerase III HE is the large multiprotein complex responsible for elongation of DNA replication in E. coli. It has atleast 10 subunits, each with specific function. Other proteins involved in DNA elongation are DNA gyrase (topoisomerase), which removes the topological strain associated with DNA unwinding SSB (single stranded DNA binding) protein, that binds tightly to single stranded DNA thus stabilizing the unwound DNA. RNase H remove.

1. Initiation of DNA replication in prokaryotes involves loading and activation of DnaB helicase.
DnaB helicase directs other necessary enzymes (particularly DnaG Primase and DNA pol III
HE) to the template and help in DNA elongation. These aspects will be discussed below:
DnaB protein
DnaB is the major helicase, it unwinds the template in 5'-3' direction during oriC replication in
vitro, at a rate of 700bp/sec. The direction of unwinding requires DnaB to be placed on lagging
strand, ahead of the polymerase on the leading strand. It also activates primer synthesis by DnaG
primase.
DnaG primase
The primase (DnaG) synthesizes a unique oligonucleotide primer on SSB coated single stranded
phage G4 DNA. The sequence recognised by primase is over 100 nucleotides long containing a
secondary structure. Since primer synthesis requires activation by DnaB, the latter is oftern
described as a 'mobile promoter' of primer synthesis.
DNA polymerase III holoenzyme
DNA polymerase III HE is the large multiprotein complex responsible for elongation of DNA
replication in E. coli. It has atleast 10 subunits, each with specific function.
Other proteins involved in DNA elongation are
DNA gyrase (topoisomerase), which removes the topological strain associated with DNA
unwinding
SSB (single stranded DNA binding) protein, that binds tightly to single stranded DNA thus
stabilizing the unwound DNA.
RNase H removes RNA primers
DNA Polymerase I is used for filling the gap created due to the removal of RNA primers
DNA ligase converts the okasaki fragments into a continuous strand.
Solution
Initiation of DNA replication in prokaryotes involves loading and activation of DnaB helicase.
DnaB helicase directs other necessary enzymes (particularly DnaG Primase and DNA pol III
HE) to the template and help in DNA elongation. These aspects will be discussed below:
DnaB protein
DnaB is the major helicase, it unwinds the template in 5'-3' direction during oriC replication in
vitro, at a rate of 700bp/sec. The direction of unwinding requires DnaB to be placed on lagging
strand, ahead of the polymerase on the leading strand. It also activates primer synthesis by DnaG
primase.

2. DnaG primase
The primase (DnaG) synthesizes a unique oligonucleotide primer on SSB coated single stranded
phage G4 DNA. The sequence recognised by primase is over 100 nucleotides long containing a
secondary structure. Since primer synthesis requires activation by DnaB, the latter is oftern
described as a 'mobile promoter' of primer synthesis.
DNA polymerase III holoenzyme
DNA polymerase III HE is the large multiprotein complex responsible for elongation of DNA
replication in E. coli. It has atleast 10 subunits, each with specific function.
Other proteins involved in DNA elongation are
DNA gyrase (topoisomerase), which removes the topological strain associated with DNA
unwinding
SSB (single stranded DNA binding) protein, that binds tightly to single stranded DNA thus
stabilizing the unwound DNA.
RNase H removes RNA primers
DNA Polymerase I is used for filling the gap created due to the removal of RNA primers
DNA ligase converts the okasaki fragments into a continuous strand.