T4 DNA ligase

YTA-T4 DNA Ligase catalyzes the joining of two strands of DNA between the 5′ phosphate group of the donor and the 3′ hydroxyl group of the ligand to form a 3′ → 5′ phosphodiester bond in either a cohesive-ended or blunt-ended configuration. the substrate of this enzyme is double stranded DNA and will not join single stranded nucleic acids.