NEB extensively performs quality controls on all standard and high-fidelity (HF®) restriction enzymes. Examples of nuclease contamination studies for some of our HF restriction enzymes are shown below. 

Restriction Enzyme Competitor Study: Nuclease Contamination


EcoRI, NotI, and BamHI from multiple suppliers were tested in reactions containing a fluorescent labeled single stranded, double stranded blunt, 3’overhang or 5’ overhang containing oligonucleotides. The percent degradation is determined by capillary electrophoresis and peak analysis. The resolution is at the single nucleotide level.

Product Source

An E. coli strain that carries the cloned and modified BstZ17I gene from Bacillus stearothermophilus38M (Z. Chen).

Reagents Supplied

The following reagents are supplied with this product:

Unit Definition

One unit is defined as the amount of enzyme required to digest 1 µg of λ DNA in 1 hour at 37°C in a total reaction volume of 50 µl.

Reaction Conditions
1X CutSmart® Buffer
Incubate at 37°C

1X CutSmart® Buffer:
50 mM Potassium Acetate
20 mM Tris-acetate
10 mM Magnesium Acetate
100 μg/ml BSA
pH 7.9 @ 25°C

Activity in NEBuffers
NEBuffer 1.1: 100%
NEBuffer 2.1: 100%
NEBuffer 3.1: 10%
CutSmart® Buffer: 100%

Diluent Compatibility
Diluent A

Storage Temperature
-20°C

Storage Conditions
10 mM Tris-HCl
50 mM KCl
1 mM DTT
0.1 mM EDTA
200 μg/ml BSA
50% Glycerol
pH 7.4 @ 25°C

Heat Inactivation
No

Methylation Sensitivity
dam methylation: Not Sensitive
dcm methylation: Not Sensitive
CpG Methylation: Blocked by Some Combinations of Overlapping 

Companion Products

• CutSmart® Buffer
• Gel Loading Dye, Purple (6X)
• Monarch® Plasmid Miniprep Kit 
• Monarch® DNA Gel Extraction Kit
• Monarch® PCR & DNA Cleanup Kit (5 μg)

1. BstZ17I is an isoschizomer of BssNAI and Bst1107I.

2. For enzymes that cannot be heat-inactivated, we recommend using a column for cleanup (such as the Monarch® PCR & DNA Cleanup Kit), or running the reaction on an agarose gel and then extracting the DNA (we recommend Monarch Gel Extraction Kit), or performing a phenol/chloroform extraction.