DNase I
DNase I (Deoxyribonuclease I) is an endodeoxyribonuclease that can digest single- or double- stranded DNA. It recognizes and cleaves phosphodiester bonds to produce monodeoxynucleotides or single- or double- stranded oligodeoxynucleotides with phosphate groups at the 5′-terminal and hydroxyl at the 3′-terminal. The activity of DNase I depends on Ca2+ and can be activated by divalent metal ions such as Mn2+ and Zn2+. 5mM Ca2+ protects the enzyme from hydrolysis. In the presence of Mg2+, the enzyme could randomly recognize and cleave any site on any strand of DNA. In the presence of Mn2+, the double strands of DNA can be simultaneously recognized and cleaved at almost the same site to form flat end DNA fragments or sticky end DNA fragments with 1-2 nucleotides protruding.
Product Property
Bovine Pancreas DNase I was expressed in yeast expression system and purified.
Components
|
Component |
Volume |
|||
|
0.1KU |
1KU |
5KU |
50KU |
|
|
DNase I, RNase-free |
20μL |
200μL |
1mL |
10mL |
|
10×DNase I Buffer |
1mL |
1mL |
5× 1mL |
5× 10mL |
Transportation and Storage
1. Storage Stability: – 15℃~-25℃ for storage;
2.Transport Stability: Transport under ice packs;
3. Supplied in: 10 mM Tris-HCl, 2 mM CaCl2, 50% glycerol, pH 7.6 at 25℃ .
Unit Definition
One unit is defined as the amount of enzyme which will completely degrade 1 µg of pBR322 DNA in 10 minutes at 37°C.
Quality Control
RNase: 5U of DNase I with 1.6 μg MS2 RNA for 4 hours at 37 ℃ yields no degradation as determined by agarose gel electrophoresis.
Bacterial Endotoxin: LAL-test, according to Chinese Pharmacopoeia IV 2020 edition, gel limit test method, general rule (1143). Bacterial endotoxin content should be ≤10 EU/mg.
Instructions for Use
1.Prepare the reaction solution in the RNase-free tube according to the proportions listed below:
|
Component |
Volume |
|
RNA |
X μg |
|
10 × DNase I Buffer |
1 μL |
|
DNase I, RNase-free(5U/μL) |
1 U per μg RNA |
|
ddH2O |
Up to 10 μL |
2.37 ℃ for 15 minutes;
3.Add the termination buffer to stop the reaction, and heat at 65℃ for 10 minutes to inactivate DNase I. The sample can be directly used for the next transcription experiment.
Notes
1.Use 1U DNase I per μg of RNA, or 1U DNase I for less than 1μg of RNA.
2.EDTA should be added to a final concentration of 5 mM to protect RNA from being degraded during enzyme inactivation.
