Taq DNA Ligase is a NAD⁺ dependent thermostable DNA ligase that catalyses the formation of a phosphodiester bond between juxtaposed 5 ́ phosphate and 3 ́ hydroxyl termini of two adjacent nucleotides in the context of a double-stranded DNA molecule. The ligation will occur only if the adjacent nucleotides are perfectly paired and have no gaps between them, thus allowing the use of this enzyme as a tool to detect single-base substitutions. As expected from its origin from a thermophilic host, Taq DNA Ligase is active at elevated temperatures (45–65°C). Due to critical differences in substrate specificity, Taq DNA Ligase is not a substitute for T4 DNA Ligase and it is not suitable for cloning applications or adapter ligation/NGS library prep. Taq DNA Ligase is primarily used in molecular diagnostic applications and for direct cloning applications.
Applications:
– Direct cloning
– Ligation-based molecular diagnostic techniques (e.g. Ligase Chain Reaction, LCR; Ligase Detection Reaction, LDR)
– Detection of single-base substitutions