Cat. No. / ID: Not Applicable
Tth DNA Ligase catalyzes the NAD-dependent formation of phosphodiester bonds between adjacent 3’-hydroxyl and 5’-phosphate termini in double-stranded DNA. It is not active against single-stranded DNA or RNA and blunt-ended DNA. The enzyme is isolated from the Escherichia coli strain containing a plasmid carrying the Thermus thermophilus DNA ligase gene.
It is supplied with 50 mM Tris-HCl (pH 7.5), 100 mM NaCl, 0.1 mM EDTA, 0.1% Triton X-100, 1 mM DTT, 50% glycerol.
One unit of Tth DNA Ligase catalyzes the ligation of 50% of the cos sites present in 1 μg of bacteriophage lambda DNA in 1 minute at 45°C. One unit of Tth DNA Ligaseiq equivalent to 15 cohesive end units (CEU).
|DNase contamination||None detected|
|Exonuclease activity||None detected|
|Endonuclease activity||None detected|
Tth DNA Ligase is stable and active in an optimum ligation temperature range of 45 – 65°C, which is 7 – 10°C higher than T4 DNA ligase. The Tm of the substrates determines the final reaction ligation temperature. High ligation temperature eliminates nonspecific ligation.
Tth DNA ligase activity is assayed in a reaction containing 1 g of bacteriophage lambda DNA digested with SalI and SmaI (Control DNA), 1x Tth Ligation Buffer and varying amounts of enzyme for 100 minutes at 450°C. Results are assayed by agarose gel electrophoresis. The product is free of unspecific DNA nucleases. Results are assayed by agarose gel electrophoresis following incubation of 1 g of DNA substrate with 5 U of Tth ligase enzyme for 4 hours at 700°C.
This is used for applications such as: