Ligase is an enzyme that facilitates the joining of DNA strands together by catalyzing the formation of a phosphodiester bond. It plays a crucial role in DNA replication and repair.
5 Must Know Facts For Your Next Test
1. Ligase is essential for sealing nicks in the sugar-phosphate backbone of DNA during replication.
2. It specifically acts on the lagging strand to join Okazaki fragments into a continuous strand.
3. ATP or NAD+ are commonly used cofactors for ligase activity, providing the necessary energy for bond formation.
4. In prokaryotes, DNA ligase I is primarily responsible for joining the fragments.
5. Mutations or deficiencies in ligase can lead to errors in DNA replication, potentially resulting in genetic disorders.
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Related terms
Helicase: An enzyme that unwinds the DNA double helix ahead of the replication fork
Okazaki Fragments: Short sequences of DNA nucleotides which are synthesized discontinuously and later linked by ligase
DNA Polymerase III: The primary enzyme responsible for DNA synthesis during replication