Overexpression, purification and crystallization of a thermostable DNA ligase from the archaeon Thermococcus sp. 1519

DNA ligases catalyze the sealing of 5'-phosphate and 3'-hydroxyl termini at single-strand breaks in double-stranded DNA and their function is essential to maintain the integrity of the genome in DNA metabolism. An ATP-dependent DNA ligase from the archaeon Thermococcus sp. 1519 was overexpressed, purified and crystallized. Crystals were obtained using the hanging-drop vapour-diffusion method employing 35%(v/v) Tacsimate pH 7.0 as a precipitant and diffracted X-rays to 3.09 Å resolution. They belonged to space group P4₁2₁2, with unit-cell parameters a = b = 79.7, c = 182.6 Å.