Merck, 11284932001, DNase I

General description
DNase I is a double-strand specific endonuclease that degrades DNA. Bovine pancreatic deoxyribonuclease I (DNase I) is a DNA minor grove-interacting nuclease, which shows relatively low specificity. This protein is composed of two central β sheets, each composed of six β-strands. This structure is surrounded by extensive loop and α-helical regions. This enzyme shares structural similarity to exonuclease III. DNase I is one of the most well characterized endonucleases of mammalian origin.
Application
DNase I has been used for tissue dissociation in conjunction with collagenases.
Biochem/physiol Actions
During tissue dissociation, parts of the cells are lysed resulting in a release of DNA. Monomolecular DNA may cause clumping of cells. Addition of DNase I to the dissociation buffer leads to a degradation of this extracellular DNA, therby avoiding the loss of cells from undesired clumping.
Features and Benefits
Lyophilized
Filtered through 0.2 μm pore size membrane before lyophilization
Glycoprotein and double-strand-specific endonuclease

Preparation Note
Activator: Bivalent metal ions (Ca²⁺, Mg²⁺)
Working concentration: 0.01 to 1 mg/ml
Note: For each cell type the working concentration has to be determined individually. For optimal activity the enzyme needs 5 mM Mg²⁺.
Reconstitute the lyophylizate in sterile double-distilled water (10 mg/ml); further dilution with PBS (phosphate buffered saline), HBSS (Hank′s Balanced Salt Solution) or medium.
Other Notes
For life science research only. Not for use in diagnostic procedures.
One unit is the enzyme activity which yields an increase in absorbance of 0.001 per minute under the assay conditions.