BenzNuclease DNA and RNA Nuclease(Ultra Pure,Protease Free)

Fig.1 The purity of BenzNuclease was determined by SDS-PAGE reduced and staining overnight with Coomassie Blue.

1. Reagents and solutions preparation

Reaction buffer*:

50 mM Tris-HCl, 1 mM MgCl₂, pH 8.0 ( * In the case of extensive dilution before use, carrier protein such as 0.1 mg/ml HSA or BSA is generally recommended to avoid any enzyme loss from surface adsorption)

DNA Substrate:

1 mg/ml salmon sperm DNA is dissolved overnight at 4 ℃, in reaction buffer, and is then sonicated on ice to obtain a homogenous solution.

Enzyme:

Different dilution of nuclease with reaction buffer.

Stop reagent:

Trichloroacetic acid (TCA)

2. Standard curve establishment

400 μl substrate + 100 μl enzyme of known activity = 500 μl mixture

1. Incubate the mixture at 37℃ for 30 min.

2. Stop the reaction by addition of 400 μl cold TCA and incubate on ice for 10 min.

3. Centrifuge at 8500g for 5 min.

4. Measure the absorbance of supernatant at 260 nm.

5. Lot a standard curve with nuclease of known activities for each set of measurements.

3. Measurement of activity

The activity of any unknown nuclease can be determined from a single measurement by means of the standard curve. The specific activity of BenzNuclease is >1.5 x 10e6 unit/mg protein.

Fig 2. Standard curve of nuclease activity for BenzNuclease.