NURSING ANM AND GNM

Detailed explanation-1: -The reaction catalyzed by DNA ligase. This enzyme seals a broken phosphodiester bond. As shown, DNA ligase uses a molecule of ATP to activate the 5′ end at the nick (step 1) before forming the new bond (step 2).

Detailed explanation-2: -If two DNA molecules have matching ends, they can be joined by the enzyme DNA ligase. DNA ligase seals the gap between the molecules, forming a single piece of DNA.

Detailed explanation-3: -DNA ligase joins the Okazaki fragments together into a single DNA molecule. Helicase opens up the DNA at the replication fork. Single-strand binding proteins coat the DNA around the replication fork to prevent rewinding of the DNA. Topoisomerase works at the region ahead of the replication fork to prevent supercoiling.

Detailed explanation-4: -Abstract. DNA ligase 1 (LIG1, Cdc9 in yeast) finalizes eukaryotic nuclear DNA replication by sealing Okazaki fragments using DNA end-joining reactions that strongly discriminate against incorrectly paired DNA substrates.