Deoxyribonuclease I (DNase I), 2u/ul, Solution

Molecular Biology / MB-Cloning-Enzymes

-20°C

Supplied as a liquid in 1mM calcium chloride, 50% glycerol.

Endonuclease which digests dsDNA by hydrolysis of deoxyribonucleotide linkages, producing 3’-hydroxyl oligonucleotides.

Applications:
Nick Translation
DNase I DNA Footprinting
Cloning of Random DNA Fragments

Activity:
~2000u/ml

Unit Definition:
1 unit causes an increase in absorbance at 260 nm of 0.001 per minute per ml at 25ºC when acting upon highly polymerized DNA at pH 5.0.

Assay Method:
Based on the Kunitz method where DNase will depolymerize DNA; 1 Kunitz units digests 1ug of lambda DNA in 10 minutes at 37°C in 50mM Tris, 1mM Ca+2 and 1mM Mg+2, pH 7.8 in a 50ul reaction. Correlation of digestion units with Kunitz is different for other DNA and buffer systems

Quality Control:
SDS-PAGE

RNase:
None Detected

Protease:
None Detected

Storage and Stability:
May be stored at 4°C for short-term only. Protect from moisture. For long-term storage, store at -20°C. Aliquots with 50% glycerol are stable for 6 months at -20°C.

Note: Pancreatic DNase is highly susceptible to denaturation. Mix by gentle inversion.