产品名称

Deoxyribonuclease I from bovine pancreas

别 称

DNase I, Deoxyribonucleate 5′-oligonucleotido-hydrolase

含 量

≥2,000 Kunitz units/mg protein; Type IV

CAS  NO.

9003-98-9

分子量

mol wt ~31 kDa

MDL  number

MFCD00130918

适用范围

生物试剂

l  理化信息

外 观

白色至淡黄色至淡褐色冻干粉末

物理形态

Lyophilized powder containing calcium chloride

溶解性(25°C)

0.15 M NaCl: soluble 5.0 mg/mL, clear, colorless

l  生物学信息

生物活性/药理作用

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. Only minor amounts of D are found. 2-Mercaptoethanol, chelators, sodium dodecyl sulfate (SDS) and actin are known to inhibit the enzyme activity.

应 用

Used for the removal of DNA from protein samples.

DNAse I is used to nick DNA as a first step to incorporate labeled s into DNA. The enzyme from Sigma has been used in the processing of rat brain tissue. This study showed that axonal growth on  astrocytes is not inhibited by oligodendrocytes.In another study, thawed fixed samples of E. coli were digested with DNAse I from Sigma along with other enzymes. The digestion was done before permeabilization and staining of the nucleic acids.Deoxyribonuclease I from bovine pancreas has been used in a study to investigate a two-dimensional zymogram analysis of nucleases in  Bacillus subtilis. Deoxyribonuclease I from bovine pancreas has also been used in a study to investigate the effects of minor and major groove-binding drugs and intercalators on the DNA association of minor groove-binding  proteins RecA and deoxyribonuclease I.

样品准备说明

10 mg/mL solution of DNAse I in 0.15M 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 pH5 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 1mg/mL concentration.

有效单位定义

One Kunitz unit will produce a ΔA²⁶⁰ of 0.001 per min per mL at pH5.0 at 25°C, using DNA, Type I or III as substrate.

l  存储

存储温度

-20°C

l  注意事项及免责声明

本产品仅用于实验研究，不得作为药物使用，不得用于家用或其它用途。

l  参考文献

1.    http://www.drugbank.ca

2.    https://ncit.nci.nih.gov

3.    https://www.ncbi.nlm.nih.gov