BsiHKCI
(Bacillus stearothermophilus HKC)
5’-C Py C G Pu G-3’
3’-G Pu G C Py C-5’
Note 1: Purified from E.coli strain that carries the cloned bsiHKCRI gene.
Reaction Temperature: 65°C
Prototype: AvaI
Inactivation Temperature (20 min): no
Reaction Buffer:
1x Medium Buffer: 10 mM Tris-HCl (pH 7.5 at 37°C), 10 mM MgCl2, 50 mM NaCl, 1 mM dithiothreitol, 100 µg/ml bovine serum albumin.
Unit Definition: One unit is the amount of enzyme required to completely digest 1 µg of lambda DNA in 1 hr in a total reaction volume of 50 µl.
Assay Conditions: 10 mM Tris-HCl (pH 7.5 at 37°C), 50 mM NaCl, 10 mM MgCl2, 1 mM dithiothreitol, 100 µg/ml bovine serum albumin and 1 µg of lambda DNA. Incubation is at 65°C for 1 hr in a reaction volume of 50 µl.
Storage Buffer: 10 mM Tris-HCl (pH 7.5 at 22°C), 50 mM KCl, 1 mM dithiothreitol, 0.1 mM EDTA and 50% (v/v)glycerol.
Storage Conditions: Store at –20°C.
Quality Control:
Non-specific Endonuclease: Incubation of 10 units of BsiHKCI with 1 µg of lambda DNA at 65°C for 16 hrs (a 160-fold over-digestion) resulted in the same sharp characteristic banding pattern as the standard assay reaction, as determined by agarose gel electrophoresis.
3'-Exonuclease: 5, 10 and 20 units of BsiHKCI and 0.13 µg of lambda/TaqI fragments (3'-labeled with T4 DNA Polymerase and [³H]dGTP and [³H]dCTP), incubated for 1 hr at 65°C resulted in 0.0 slope of %-end label released per unit of enzyme. Reaction volume 10 µl.
5'-Exonuclease/5'-Phosphatase: Incubation of 5, 10 and 20 units of BsiHKCI with 0.05 µg of [5'-³²P] lambda/HaeIII fragments for 1 hr at 65°C resulted in 0.08-slope of %-end label released per unit of enzyme. Reaction volume 10 µl.