The Steps and Proteins involved in DNA Replication (Prokaryotic and Eukaryotic)

It is now well established that DNA Replication occurs semi conservatively, copying each strand of DNA separately, to produce two new DNA double helices. Each is composed of an old(Parent) strand and a newly synthesized one.
semi conservatively replication
Meselson and Stahl in 1958 and J.Cairns in 1963 experimentally verified that the DNA of E.coli replicates semi conservative manner. J.H.Taylor confirmed semi conservative replication of DNA in Vicia faba chromosomes in 1963.

The Steps and Proteins involved in DNA Replication (Prokaryotic and Eukaryotic)
Prokaryotic cells

Eukaryotic cells

Unwinding of DNA double helix at replication origins(s)
Helicase (Requires ATP)
Helicase (Requires ATP)
Stabilization of unbound template strands
Single strand binding protein (SSB)
Single strand binding protein (SSB)
Synthesis of DNA
leading strand
lagging strand
(Okazaki fragment)

DNA polymerase III
DNA polymerase III

DNA polymerase delta
DNA polymerase alpha
Removal of RNA primers
DNA polymerase I( 5’-exonuclease)
Replacement of RNA with DNA
DNA polymerase I
Joining of okazaki fragments
DNA ligase I
(Requires NAD)
DNA ligase I
(Requires ATP)
Removal of supercoils ahead of advancing replication forks
Topoisomerase II
(DNA gyrase)
(Inhibited by nalidixic acid, norfloxacin)
Topoisomerase II
(Inhibited by etoposide, teniposide
Synthesis of telomers
Not required

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