What is the difference between Ligase and DNA polymerase?

DNA ligase seals DNA backbone by producing a phosphodiester bond.
DNA polymerase synthesizes DNA.
If you want more information, look up DNA polymerase I (DNAP I).
DNAP I contains 3 functioning domains. 5'-->3' polymerase activity,    5'-->3' exonuclease activity, and 3'-->5' proofreading exonuclease activity.


DNA ligase uses a cofactor called NAD to create the phosphodiester bond.
Basically, the mechanism is similar to adding DNA nucleotides to a growing chain. The 3'OH attacks a pyrophosphate and the product releases a phosphate.

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