T7 Exonuclease is similar to Lambda Exonuclease in that it catalyzes the stepwise hydrolysis of duplex DNA from the 5'-termini, liberating 5'-mononucleotides. However, unlike Lambda Exonuclease, the enzyme has low processivity and it will remove both 5'-hydroxyl and 5'-phosphoryl termini. T7 Exonuclease hydrolyzes duplex DNA non-processively in the 5' -> 3' direction from both 5'-phosphoryl or 5'-hydroxyl nucleotides by liberating oligonucleotides, as well as mononucleotides, until about 50% of the DNA is acid soluble.
Purified from an E. coli strain containing a TYB12 intein fusion.
10 mM Tris-HCl
5 mM DTT
0.1 mM EDTA
pH 8.0 @ 25°C
- Controlled stepwise digestion of double-stranded DNA from the 5'-termini.
- Generating ssDNA templates for sequencing via the chain-termination method.
10X T7 Exonuclease Buffer
10X T7 Exonuclease Buffer:
500 mM Potassium Acetate
200 mM Tris-acetate
100 mM Magnesium Acetate
10 mM DTT
pH 7.9 @ 25°C
One unit is the amount of enzyme required to release 1 nmol of acid soluble nucleotide in 15 min at 37°C under standard assay conditions.
Recommended Storage Condition: -20°C
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