DNA Replication In Prokaryotes

 DNA Replication In Prokaryotes:-

Fig: DNA replication in prokaryotes

Replication is the duplication process of DNA. Among prokaryotes, DNA replication is clearly studied in E.coli. It occurs in the bacterial chromosomes. DNA has the ability for self duplication. This DNA duplication is a semi conservative process.

  The replication process is bidirectional & semi discontionuous. The synthesis occurs always from the 5^th to the 3^rd direction. In replication, the parent strands are function as templates. The newly synthesized strand is complementary to the parental strand. During replication Dihydroxyribonucleotides are added one by one resulting in the formation of a polynucleotide chain. This process is Known as polymerisation. In this process addition of nucleotides are catalysed by an enzyme called DNA Polymerase III.

The process of replication involves 3 steps namely:-

1) Initiation: In this step DNA strands are unwinding & start to separation.

2) Elongation: In tghis step nucleotides are linking.

3) Termination: It is tge end step of replication where it become stop.

 

     At the time of replication, as a result of the two DNA strands open & separate at the origin. Helices enzyme help to unwinds the DNA strand. The separation of DNA strand form an eye like structures on the origin called replication fork.

    In replication, single stranded binding proteins bind to the separated DNA strands. They hold the DNA strand & prevent them from folding, The unwinding   creates twisting on the double helix near the replication fork. It removes the twists caused by the unwinding action of Helicase.