T4 DNA LIGASE

Uses

Forms an energy dependent phosphodiester linkage between the termini of adjacent polynucleotides of duplex DNA. For ligation of cloning vector and restriction insert fragments

General Description

T4 DNA Ligase catalyzes the formation of phosphodiester bonds between neighboring 3′-hydroxyl- and 5′-phosphate ends in double-stranded DNA. Single-stranded nicks in double-stranded DNA are also closed by T4 DNA Ligase.

Contents
T4 DNA Ligase, supplied with 10x concentrated ligation buffer that includes ATP.

Biological Activity

T4 DNA Ligase forms an energy dependent phosphodiester linkage between the termini of adjacent polynucleotides of duplex DNA. The ligation reaction requires ATP as a cofactor. Ligation of blunt-ended fragments requires higher enzyme concentration and can be facilitated by using PEG in the reaction mixture. The enzyme requires a 3μ hydroxyl and 5μ phosphate for ligation. Self-ligation of vector DNA can be prevented by dephosphorylation with alkaline phosphatase. T4 ligase plays an active role in repair of DNA and RNA nicks.