Description
Quantity: 1000 U
Unit Size: Each
Properties:
• Molecular Weight: xseA subunit = 51.8 kDa; xseB subunit = 8.8 kDa
• Optimum Temperature: 37 °C
• Optimum pH: 8.0
• Inactivation: 95 °C for 10 min.Purity:Greater than 95% pure as determined by SDS-PAGE. Tested for contaminating endonucleases, double-stranded exonucleases, and ribonucleases.Storage Buffer:50 mM Tris-HCl (pH 8.0), 200 mM NaCl, 0.5 mM EDTA, 10 mM DTT, 50% glycerol.Assay Conditions:The reaction (50 μL) contains 50 mM Tris-HCl (pH 7.9), 50 mM potassium phosphate (pH 7.6), 8.3 mM EDTA, 10 mM 2-mercaptoethanol, denatured DNA, and enzyme.Unit Definition:One unit is the amount of enzyme required to catalyze the conversion of 1 nmol of nucleotide to acid-soluble nucleotide in 30 min at 37 °C under standard assay conditions.Concentration:10 units/μLSource:E. coli strain containing overproducing clones encoding both the large (xseA) and small (xseB) subunits of Exonuclease VII.Protocol: Typical Reaction Conditions (50 μL)
• 70 mM Tris-HCI, pH 8.0
• 8 mM EDTA
• 10 mM 2-mercaptoethanol
• 1 μg DNA
• 50 μg/mL
• 0.2 units Exonuclease VIIIncubate at 37 °C for 30 min. Inactivate the enzyme by heating to 95 °C for 10 min. Note that Exonuclease VII is not inhibited by EDTA.Note: A typical dilution buffer for use with Exonuclease VII is 50 mM Tris, pH 7.9, 1 mM DTT and 0.5 mg/mL acetylated BSA.Applications:
• Mapping positions of introns in genomic DNA.
• Removal of vector DNA from inserts with poly (dA-T) tails.
• Removal of excess PCR primers.
• Removal of single-stranded over-hangs produced by restriction endonucleases.
