Q1 of 805 Page 1

Name the enzyme that helps to join DNA fragments.

The enzyme that helps to join DNA fragments is DNA ligase.

Solution: During lagging strand synthesis in DNA replication, DNA ligase is responsible for joining the Okazaki fragments in the lagging strand after replacing the RNA primers.


The mechanism of DNA ligase is as follows:


It forms two covalent phosphodiester bonds between the 3' hydroxyl ends of one of the nucleotides and with the 5' phosphate end of another nucleotide. This process requires two ATP molecules for the formation of each phosphodiester bond.



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