Question

Sketch a DNA Replication fork and all of the enzymes required to

synthesize daughter strands on both sides of the parental strands

Answer 1

Enzymes and their roles involved at Replication fork:

Helicase: Helps in unwinding i.e. opens up the duplex at the replication fork to provide single stranded template.

SSB(Single stranded binding protein): A tetramer,which binds at both separated strand in order to prevent subsequent reannealing of the separated strands.

Primase: An enzyme which acts on primer to initiate the chain elongation process; DNA polymerase can only elongate existing 3'-OH gr. which is provided by primers.

DNA polymerase: DNA polymerase catalyze the synthesis of DNA.

There are 2 types :

RNA dependent DNA polymerase

DNA dependent DNA Polymerase(DNA polymerase)

There are several types of DNA polymerases in prokaryotes and eukaryotes;only some of the polymerase actually undertake replication and are termed as DNA replicase.

In prokaryotes -

DNA polymerase III is the main replicating enzyme.

In eukaryotes:

DNA polymerase delta and DNA polymerase epsilon are the replicating enzymes.

​​​​DNA ligase: Role in joining of Okazaki fragments.

​​​​​​The enzyme catalyzes the formation of phosphodiester bond between 3'-OH group at the end of one DNA chain and the 5'-phosphate group at the end of the other.

​​​​​​Hope this helps you... Thank you.