Question: The principle enzyme for DNA replication is:
Options:
DNA ligase
DNA helicase
DNA-dependent DNA polymerase
None of the above
-DNA replication is the biological process of producing two identical replicas of DNA from one original DNA molecule.
-It is an enzymatically governed process, many enzymes participate in DNA replication.
✅ Explanation:
-The principal enzyme for DNA replication is DNA-dependent DNA polymerase
-DNA replication process uses DNA polymerase III to catalyzes the joining of deoxyribonucleoside 5′-triphosphates (dNTPs) at a growing chain of DNA.
-DNA is read by DNA polymerase in the 3′ to 5′ direction, meaning the new strand is synthesized in the 5' to 3' direction.
-In the DNA replication process, one new strand (leading strand) is made as a continuous piece. The other (lagging strand) is made in small pieces.
-At the leading strand, DNA polymerase III synthesizes the new strand in the 5′ to 3′ direction.
-The lagging strand is elongated in an antiparallel direction, by the addition of short RNA primers (Okazaki fragment) which are filled with other joining fragments.
-The Okazaki fragments formed at the lagging strand are joined together by the enzyme DNA ligase, for this reason, DNA ligase is also called molecular glue
🔴Additional Information:: Other Important Enzyme in DNA Replication DNA Helicase enzyme: Involved in unwinding the double-helix structure of DNA, allowing replication to begin by breaking hydrogen bonds between DNA bases using ATP hydrolysis.
-Topoisomerase: Resolves topological stress during unwinding by cutting and rejoining DNA strands, allowing them to move around each other to release tension.
-DNA Primase enzyme: Synthesizes short RNA molecules that serve as templates for initiating DNA replication.
-DNA Ligase enzyme: Joins DNA fragments together by forming phosphodiester bonds between nucleotides.