Describe various enzymes involved in $DNA$ replication.

Vedclass pdf generator app on play store
Vedclass iOS app on app store
(N/A) The process of replication requires a set of catalysts (enzymes) as described below:
$DNA$-dependent $DNA$ polymerase: This is the main enzyme that uses a $DNA$ template to catalyze the polymerization of deoxynucleotides. These enzymes are highly efficient as they must catalyze the polymerization of a large number of nucleotides in a very short time. For example,$E. coli$ completes replication of its $4.6 \times 10^{6}$ bp genome in $38$ minutes,requiring an average polymerization rate of approximately $2000$ bp per second. These polymerases must be fast and highly accurate,as mistakes lead to mutations. Energetically,replication is expensive; deoxyribonucleoside triphosphates serve dual purposes: acting as substrates and providing energy for the polymerization reaction (the two terminal phosphates are high-energy,similar to $ATP$). In prokaryotes,there are three types ($DNA$ polymerase $I, II, III$),while in eukaryotes,five types $(\alpha, \beta, \gamma, \delta, \varepsilon)$ have been identified. They also perform proofreading to remove mismatched nucleotides.
Helicase: It unwinds the $DNA$ helix by separating the two strands at a specific point to form the replication fork.
Topoisomerase: The unwinding of $DNA$ creates supercoiling tension,which is released by the enzyme topoisomerase.
$DNA$ ligase: It facilitates the joining of $DNA$ fragments (Okazaki fragments) by catalyzing the formation of phosphodiester bonds. It also plays a role in repairing single-strand breaks in duplex $DNA$.
Primase: It synthesizes short $RNA$ primers that are necessary for $DNA$ polymerase to initiate the synthesis of new $DNA$ strands.

Explore More

Similar Questions

Give scientific reasons: $DNA$ polymerase plays a dual function during $DNA$ replication.

On which template strand of $DNA$ does continuous replication occur?

Which enzyme is responsible for the synthesis of small $RNA$ fragments during $DNA$ replication?

Where does the replication of $DNA$ begin?

The mode of $DNA$ replication in $E. coli$ is:

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo