l General Information |
Product Name | Deoxyribonuclease I from bovine pancreas |
Synonym | DNase I, Deoxyribonucleate 5′-oligonucleotido-hydrolase |
Assay | Protein ≥80 %, ≥2,000 units/mg protein; Type II | CAS Number | 9003-98-9 |
Molecular Weight | mol wt ~31 kDa | MDL number | MFCD00130918 |
Suitability | BioReagent |
l Physical and Chemical Information |
Appearance | White to Off-White lyophilized powder |
Solubility(25°C) | 0.15 M NaCl: soluble 5.0 mg/mL, clear |
l Biological Information |
Biochem/Physiol Actions | DNase I is an endonuclease that acts on phosphodiester bonds adjacent to pyrimidines to produce polynucleotides with terminal 5′-phosphates. In the presence of Mg2+, DNAse I cleaves each strand of DNA independently and the cleavage sites are random. Both DNA strands are cleaved at approximately the same site in the presence of Mn2+. The pH optimum is found to be between 7 and 8. Divalent cations such as Mn2+, Ca2+, Co2+, and Zn2+ are activators of the enzyme.A concentration of 5 mM Ca2+ stabilizes the enzyme against proteolytic digestion. DNAse I from bovine pancreas consists of four chromatographically distinguishable components, A, B, C, and D, with their molar ratios being 4:1:1 respectively. Only minor amounts of D are found. 2-Mercaptoethanol, chelators, sodium dodecyl sulfate (SDS)and actin are known to inhibit the enzyme activity. |
Application | Used for the removal of DNA from protein samples. DNAse I is used to nick DNA, as a first step to incorporate labeled bases into DNA. The enzyme from Sigma has been used in the nuclease stock along with RNAse during cell lysate preparation of Madin-Darby canine kidney (MDCK) II cell lines. It has also been used during RNA extraction from Sindbis virus. Deoxyribonuclease I from bovine pancreas has been used for the identification, localization and of two novel human genes similar to deoxyribonuclease I. Deoxyribonuclease I from bovine pancreas has also been used in a study to investigate a new approach to obtaining high-activity RNase, DNase, cholesterolesterase, and trypsin from cattle pancreas. |
Preparation Note | The enzyme powder may be reconstituted in water or any buffer at pH 4.0-9.0, except phosphate buffer. Calcium chelators should be avoided. 10 mg/mL solution of DNAse I in 0.15 M NaCl may lose <10% of its activity when stored for a week in aliquots at −20 °C. The same solutions stored in aliquots at 2-8 °C can lose approximately 20% activity. It remains active for up to five hours at 60 °C between pH 5 and 7, and loses activity in <10 minutes at 68 °C. It loses activity at the rate of 6%/hour in acetate buffer (pH 5.0) and tris buffer ((pH 7.2) at 1 mg/mL concentration. |
Unit Definition | One Kunitz unit will produce a change in A260 of 0.001 per minute per ml at pH 5.0 at 25 °C using DNA, Type I or III, as the substrate. |
l Packaging & Storage |
Storage temp. | -20°C |
l Precautions and Disclaimer |
This product is for R&D use only, not for drug, household, or other uses. |
l References |
1. http://www.drugbank.ca 2. https://ncit.nci.nih.gov 3. https://www.ncbi.nlm.nih.gov |
