DNA ligases: Structure, reaction mechanism, and function

With the participation of DNA ligases in multiple different DNA metabolic pathways, the genetic inactivation of DNA ligases causes pleiotropic phenotypes including lethality and hypersensitivity to DNA damaging agents. DNA ligases are the enzymes that catalyze phosphodiester bond formation. The discussion of the reaction mechanism of DNA ligases in the context of the structural information for bacterial, viral, and human DNA ligases and the description of protein partners of the DNA ligases and how the protein-protein interactions occur are presented. Insights into the DNA ligation reaction mechanism from the structures of nucleotidyl transferases and protein partners of mammalian DNA ligases are also discussed.