Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2001 May;Chapter 3:Unit3.14.
doi: 10.1002/0471142727.mb0314s08.

DNA Ligases


DNA Ligases

S Tabor. Curr Protoc Mol Biol. .


DNA ligases catalyze the formation of phosphodiester bonds between juxtaposed 5' phosphate and a 3'-hydroxyl terminus in duplex DNA. This activity can repair single-stranded nicks in duplex DNA and join duplex DNA restriction fragments having either blunt ends or homologous cohesive ends. Two ligases are used for nucleic acid research and their reaction conditions and applications are described in this unit: E. coli ligase and T4 ligase. These enzymes differ in two important properties. One is the source of energy: T4 ligase uses ATP, while E. coli ligase uses NAD. Another important difference is their ability to ligate blunt ends; under normal reaction conditions, only T4 DNA ligase will ligate blunt ends.

Similar articles

See all similar articles

LinkOut - more resources