DNA Ligases

  title={DNA Ligases},
  author={Stanley Tabor},
  journal={Current Protocols in Molecular Biology},
  • Stanley Tabor
  • Published 2001
  • Chemistry, Medicine
  • Current Protocols in Molecular Biology
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… Expand
1 Citations


Polymer-stimulated ligation: enhanced blunt- or cohesive-end ligation of DNA or deoxyribooligonucleotides by T4 DNA ligase in polymer solutions.
The rates of blunt-end and cohesive-end ligation of DNA by T4 DNA ligase are increased by orders of magnitude in the presence of high concentrations of a variety of nonspecific polymers, and the use of polyethylene glycol 6000 in such systems is characterized in some detail. Expand
Macromolecular crowding allows blunt-end ligation by DNA ligases from rat liver or Escherichia coli.
It is suggested that blunt-end ligation may be a widely occurring reaction in vivo, and the previously established activity of T4 DNA ligase on blunt-ended molecules is greatly increased in the presence of high concentrations of macromolecules. Expand
Enzymatic Joining of Polynucleotides
Polydeoxythymidylate in which the 5’-terminal phosphate is linked by a pyrophosphate bond to adenosine 5’-phosphate (poly dT-adenylate) serves as an intermediate in the reactions catalyzed by theExpand
[DNA ligases].