Index >> Bacteriophages - Part One >> DNA Ligase

DNA Ligase -

DNA ligase is coded by gene 30. The enzyme consists of a single polypeptide chain (MW 65,000). It catalyses the formation of phosphodiester bonds between S'-phosphate and 31-hydroxyl termini at single stranded breaks in the DNA duplex.

Gene 30 mutants synthesize only a small amount of DNA of low molecular weight (replicative intermediates). DNA ligase also has a role in genetic recombination and ultraviolet repair.