DNA replication in prokaryotes is conservative and unidirectional, initiating at the origin of replication (Ori C) site on circular bacterial DNA. The Ori C site contains conserved repeat sequences that bind replication proteins to initiate replication through a rolling circle model, with the circular DNA replicating in one direction only. Most bacterial DNA replication follows a bi-directional theta model where the replication fork moves in both directions from the Ori C site, involving all DNA replication enzymes.

1. DNA replication in
prokaryotes

2.  John Carins (1963) studied DNA replication in E.coli
 Came to a conclusion that DNA replication is conservative
and unidirectional
 In prokaryotes, the Origin of replication (Ori C) act as the
unit of replication initiator , where it is composed of 245 nbp
 It has two conserved sequences
1)13 bp long sequence- present as 3 tandem repeat (rich
in A-T pairs)
2) 9bp sequence – present 4 times but interspread by
other sequences and it plays major in binding proteins
speciliating DNA repication

3. Unidirectional replication (Rolling circle
model of replication)
 Circular DNA molecule
In normal sense it is followed by viruses, during conjucation
of bacteria and some special cases in amphibians
Process-

4. Bi- directional replication - common mode of
replication that involves all DNA replication enzymes. This
form replication is also mentioned as Theta (ϴ model of
replication