Shop All DNA⁄RNA Modifying Enzymes

FastAP Thermosensitive Alkaline Phosphatase (1 U/µL) (Thermo Scientific™)

Thermo Scientific FastAP Thermosensitive Alkaline Phosphatase catalyzes the release of 5'- and 3'-phosphate groups from DNA, RNA, and nucleotides. This enzyme also removes phosphate groups from proteins.

FastAP is a novel alkaline phosphatase, which is active in all Thermo Scientific restriction enzyme buffers as well as in PCR buffers. It dephosphorylates all types of DNA ends (blunt, 5'- and 3'-overhangs) in 10 minutes at 37°C. The enzyme is inactivated in 5 minutes at 75°C (see Figure 1 in Supporting Data). Therefore, removal of alkaline phosphatase is not required prior to ligation.

Highlights

Recombinant enzyme
Fast dephosphorylation—10 minutes at 37°C
Fast and complete inactivation—5 minutes at 75°C
Simultaneous digestion and dephosphorylation of vector DNA
100% active in restriction enzyme and PCR buffers
PCR clean-up in conjunction with Exo I
Protein dephosphorylation

One protocol for all types of DNA ends:
• 5'-overhangs
• 3'-overhangs
• blunt-ends
• single nucleotides

Applications

• Dephosphorylation of cloning vector DNA to prevent recircularization during ligation
• Simultaneous digestion and dephosphorylation of vector DNA
• PCR product clean-up: nucleotide degradation prior to sequencing of PCR product
• Dephosphorylation of nucleic acid 5'-termini prior to labeling with T4 Polynucleotide Kinase
• Other applications where dephosphorylation of DNA and RNA substrates is necessary
• Protein dephosphorylation

Note

• Binding of FastAP Thermosensitive Alkaline Phosphatase to DNA may result in a band shift in agarose gels. To avoid this, incubate samples with 6X DNA Loading Dye & SDS Solution at 65°C for 10 minutes, and chill on ice prior to electrophoresis.
• FastAP Thermosensitive Alkaline Phosphatase is active in all restriction enzyme buffers and may be added directly to digested DNA. Heat inactivation of the restriction enzyme before dephosphorylation reaction is not necessary.

Ambion™ DNase I (RNase-free) (Invitrogen™)

Ambion DNase I (RNase-free) (E.C. 3.1.21.1) is a nonspecific endonuclease that degrades double- and single-stranded DNA and chromatin. It functions by hydrolyzing phosphodiester linkages, producing mono and oligonucleotides with a 5'-phosphate and a 3'-hydroxyl group. RNase-free DNase I is of the highest purity available and is recommended to degrade DNA in the presence of RNA when the absence of RNase is critical to maintain the integrity of the RNA. For example, DNase I is frequently used to remove template DNA following in vitro transcription, and to remove contaminating DNA in total RNA preparations (especially those from transfected cells that may contain plasmid DNA), used for ribonuclease protection assays, cDNA library contraction, and RT-PCR. DNase I requires bivalent cations (Mg2+ and Ca2+ at approximately 5 mM and 0.5 mM, respectively) for maximal activity, and has a pH optimum of 7.8.

RNase-free DNase I outperforms the competition
A research report in BioTechniques (Matthews et al., 32: 1412-1417, 2002) compared RNase contamination in DNase I preparations from Sigma, Roche, Applied Science, Qiagen, and Ambion. The results revealed that "...with the exception of Ambion®'s RNase-free DNase I, the integrity of cRNA from in vitro transcription reactions was compromised and was still contaminated with DNA. Ambion®'s DNase was used for the remaining experiments requiring DNase digestion...". Ambion® DNase I is tested for contaminating RNase and protease activity. Functionality is determined by digestion of human genomic DNA followed by quantitative real-time PCR to detect undigested DNA.

Unit definition
One unit is the amount of enzyme required to completely degrade 1 µg DNA in 10 min at 37°C, and is equivalent to 0.04 Kunitz units.

Accessory products
For an alternative to bovine DNase I, please consider Recombinant DNase I (Cat. No. AM2235). For a more-active, salt-tolerant DNase, please see the TURBO™ DNase products (Cat. Nos. AM2239 and AM2238).

TURBO™ DNase (2 U/µL) (Invitrogen™)

TURBO™ DNase cleaves double-stranded DNA nonspecifically to leave 5' phosphorylated oligodeoxynucleotides. It has increased affinity for DNA-binding and remains active in the presence of salt.

Note: this product is just the enzyme. If you would like this enzyme plus reagents to inactivate the enzyme and remove divalent cations post-digestion, please see TURBO DNA-free™ Kit.

Features of TURBO™ DNase include:

• Up to 50x more activity and 350% greater catalytic efficiency
• Efficiently degrades DNA in solutions containing up to 0.25 M salt
• Efficiently digests DNA to oligonucleotides
• Vastly superior in clearing DNA templates from in vitro transcription reactions
• RNase-free and recombinant in origin

Using TURBO™ DNase
DNase I is commonly used to clear DNA contamination from RNA samples prior to RT-PCR. Conventional DNase I has a poor affinity for DNA and cleaves DNA of low concentration very inefficiently. In addition, DNase I is very salt-sensitive; as little as 20 mM NaCl can reduce the activity of the enzyme by 30%. Finally, DNase I is purified from bovine pancreas, one of the richest natural sources of RNase A. The threat of contaminating RNase activity in DNase I preparations requires that the enzyme be exhaustively purified. In spite of these limitations, the DNase I that researchers use today is the very same enzyme that was first characterized by Kunitz more than a half-century ago.

A different DNase with superior properties to wild-type DNase I
TURBO™ DNase was developed using a protein engineering approach that introduced amino acid changes into the DNA binding pocket of wild-type DNase I. These changes markedly increase the affinity of the protein for DNA. The result is a versatile enzyme that has a 6-fold lower Km for DNA, and an ability to maintain at least 50% of peak activity in solutions approaching 200 mM monovalent salt, even when the DNA concentration is in the nanomolar (nM) range. When in vitro transcription reactions are treated with either DNase I or TURBO™ DNase, TURBO™ DNase removes 63x more of the input plasmid DNA template than the wild-type enzyme. The proficiency of TURBO™ DNase in binding very low concentrations of DNA means that the enzyme is particularly effective in removing trace quantities of DNA contamination. This becomes important for complete removal of DNA from a sample, since the cleavable DNA substrate is reduced as the DNase reaction proceeds. TURBO™ DNase thus has a functional advantage over wild-type DNase due to its superior affinity for DNA. This is best exploited in RT-PCR applications, where even a few copies of DNA can lead to a false positive outcome by PCR.

T7 Gene 6 Exonuclease (Thermo Scientific™)

The T7 Gene 6 Exonuclease hydrolyzes duplex DNA non-processively in the 5'→3' direction from both 5'-phosphoryl or 5'-hydroxyl nucleotides by liberating oligonucleotides as well as mononucleotides, until about 50% of the DNA is acid soluble. It also degrades nucleotides at the gaps and nicks of double-stranded DNA from the 5'-termini and RNA from RNA:DNA hybrids in the 5'→3' direction.

The T7 Gene 6 Exonuclease is similar to Lambda Exonuclease in that it catalyzes the stepwise hydrolysis of duplex DNA from the 5' termini liberating 5' mononucleotides. However, unlike Lambda Exonuclease, the enzyme has low processivity and it will remove both 5'-hydroxyl and 5'-phosphoryl termini.

It also degrades RNA and DNA from RNA:DNA hybrids in the 5'→3' direction but is unable to degrade either double-stranded or single-stranded RNA.

This enzyme has been used for generating single-stranded DNA templates for sequencing or SNP analysis.

Properties
Molecular Weight: 32 kDa
Optimum pH: 7.5
Optimum Temperature: 37 °C
Inactivation: 75 °C for 10 min or add 2 µL of 0.5M EDTA for a 50 µL reaction volume.

Inactivation
Heating at 75 °C for 10 min or by adding 2 µL of 0.5M EDTA for a 50 µL reaction volume.

Purity
Greater than 95% pure as determined by SDS-PAGE. Tested for contaminating endonucleases and ribonucleases.

Storage Buffer
50 mM KPO4 (pH 6.5), 1 mM EDTA, 1 mM DTT, 50% glycerol.

Assay Conditions
The reaction mixture (50 µL) contains 50 mM Tris-HCI (pH 8.1), 5 mM MgCl2, 20 mM KCI, 5 mM 2-mercaptoethanol, double-stranded DNA, and enzyme. Incubation is at 37°C for 15 min.

Unit Definition
One unit is the amount of enzyme required to release 1 nmol of acid soluble nucleotide in15 min at 37 °C under standard assay conditions.

Concentration
50 units/µL

Source
E. coli strain containing an overproducing clone of the T7 Gene 6 Exonuclease

Functional Test
Conversion of 0.5 pmol of λ DNA to single-stranded half molecules by 75 units of enzyme in 30 min at 37°C. Verification by agarose gel electrophoresis.

Applications:
  1. Controlled stepwise digestion of double-stranded DNA from the 5' termini
  2. Generating ssDNA templates for sequencing or SNP analysis

Ambion™ RNase III (Invitrogen™)

Ambion® Escherichia coli ribonuclease III (RNase III; EC 3.1.24) is a double-stranded RNA (dsRNA) specific endoribonuclease. In E. coli, RNase III cleaves ribosomal RNA (rRNA) precursors during maturation of rRNA. The enzyme cleaves dsRNA into 12–15 bp dsRNA fragments with 2 to 3 nucleotide 3' overhangs, and 5' phosphate and 3' hydroxyl termini. The termini and overhangs of RNase III cleavage products are thus the same as those produced by Dicer in the eukaryotic RNAi pathway. Transfection of RNase III cleavage products can be used to induce RNAi in mammalian cells (patent pending).

Unit Definition:
One unit is defined as the amount of enzyme catalyzing the cleavage of 1 µg of 500 bp dsRNA substrate to approximately 12–30 bp fragments in 60 min at 37°C.

Exonuclease I, standard concentration, (10 units/µL) (Applied Biosystems™)

Description:
Exonuclease I hydrolyzes single-stranded DNA in the 3'→5' direction, releasing
5'-mononucleotides and leaving the terminal 5'-dinucleotide intact. Hydrolysis is processive and cannot proceed if the 3' terminus is phosphorylated. Exonuclease I can be used to measure the endonucleolytic cleavage of covalently closed circular single-stranded DNA reacted with an endonuclease of interest. In addition, DNA helicase activity can be measured utilizing Exonuclease I.

Exonuclease I is particularly useful in preparing the products of PCR for applications involving sequencing or labeling methods. Typically, the excess primers and any other extraneous single-stranded DNA present in PCR products will interfere with subsequent enzymatic reactions involving DNA synthesis. The hydrolytic properties of Exonuclease I degrade all single-stranded DNA present in the PCR mixture allowing the product to be used more efficiently in other applications. When combined with Shrimp Alkaline Phosphatase (PN 78390) for dNTP dephosphorylation, the use of alternative purification methods, such as columns, gels or magnetic separations, are completely eliminated.

For PCR clean up with Exonuclease I, see the USB ExoSAP-IT protocol. The purchase of ExoSAP-IT provides a license to the methods of PCR clean up using Exonuclease I and SAP.


Properties:
Molecular Weight: 55 kDa
Heat Inactivation: 80°C for 15 min.
Degrades to terminal dinucleotides.
Degrades glycosylated DNA.
Optimum Temperature: 37°C

Purity:
Greater than 95% pure as determined by SDS-PAGE. Tested for contaminating endonucleases, double-stranded exonucleases, and ribonucleases.


Storage Buffer:
20mM Tris-HCI (pH 7.5), 5mM 2-mercaptoethanol, 0.5mM EDTA, 50% glycerol.

Assay Conditions:
The reaction mixture (100 µL) contains 67mM glycine buffer (pH 9.5), 10mM
2-mercaptoethanol, 6.7mM MgCl2, 0.5mM denatured DNA, and enzyme. Incubation is at 37°C for 30 min.

Unit Definition:
One unit is the amount of enzyme which catalyzes the release of 10 nmol of acid-soluble nucleotide from denatured DNA in 30 min at 37°C under standard conditions.

Concentration:
Standard Conc.: 10 units/µL, PN 70073
High Conc.: 20 units/µL, PN 72073

Functional Assay: Treated PCR product with Exonuclease I to degrade unincorporated primers before performing sequencing reaction with Sequenase™ Version 2.0 DNA Polymerase Sequencing Kit (PN 70170).

References:
GOLDMARK, P. J. AND LINN, S. (1972) J. Biol. Chem. 247, 1849-1860.
ROSAMOND, J., TELANDER, K. M. AND LINN, S. (1979) J. Biol. Chem. 254, 8646-8652.
WERLE, E., SCNEIDER C., RENNER, M., VÖLKER, M. AND FIEHN, W. (1994) Nucleic Acids Res. 22, 4354-4355.
HANKE, M. AND WINK, M. (1994) BioTechniques 17, 858-860.

DNA-free™ DNA Removal Kit (Invitrogen™)

DNA-free™ DNase treatment and removal reagents are designed for the removal of contaminating DNA from RNA samples and for the removal of DNase after treatment. Features of this reagent set include:

• Safely eliminate DNA contamination from RNA samples
• No organic extraction or heat inactivation required
• Includes novel reagent to remove DNase
• Recombinant DNase I is certified RNase-free

Inactivation and removal of DNase
DNA-free™ reagents effectively remove DNase and divalent cations from the reaction mixture. The DNase/cation removal step takes only three minutes. No organic extraction, EDTA addition, or heat inactivation is required. The DNA-free™ Kit comes complete with RNase-free DNase I, an optimized 10X Reaction Buffer, and a novel DNase Removal Reagent.

Accessory product
TURBO DNA-free™ Kit (Cat. No. AM1907) is similar to the DNA-free™ Kit but includes TURBO™ DNase, an engineered hyperactive DNase that exhibits up to 350% greater catalytic efficiency than wild type DNase. The enzyme also has a 6-fold lower Km for DNA, thus enabling effective removal of trace quantities of DNA contamination.

S1 Nuclease (100 U/µL) (Thermo Scientific™)

Thermo Scientific S1 Nuclease degrades single-stranded nucleic acids, releasing 5'-phosphoryl mono- or oligonucleotides. It is five times more active on DNA than on RNA. S1 Nuclease also cleaves dsDNA at the single-stranded region caused by a nick, gap, mismatch or loop. S1 Nuclease exhibits 3'-phosphomonoesterase activity.

The enzyme is a glycoprotein with carbohydrate content of 18%.

Applications

• Removal of single-stranded overhangs of DNA fragments
• S1 transcript mapping
• Cleavage of hairpin loops
• Creation of unidirectional deletions in DNA fragments in conjunction with Exonuclease III

Note

S1 Nuclease can introduce breaks into double-stranded DNA, RNA and DNA/RNA hybrids at high enzyme and low salt concentrations.

Ribonuclease H, from E. coli (cloned) 10 U/μL (Invitrogen™)

Ambion® Ribonuclease H (RNase H) is isolated from an E. coli strain that over-expresses the gene. RNase H specifically degrades the RNA in RNA:DNA hybrids to produce 3' -hydroxyl and 5' -phosphate terminated products. It is supplied in one tube containing 200 U (10 U/ µL). The enzyme will not degrade DNA or unhybridized RNA. RNase H is an integral part of most RNA amplification and NASBA protocols. It can also be used to degrade specific RNAs when the complementary DNA oligo is hybridized, such as poly(A) tail removal from mRNA hybridized to oligo(dT). Ribonuclease H is rigorously tested for contaminating nonspecific endonuclease, exonuclease, RNase, and protease activity.

Unit Definition:
One unit of Ribonuclease H is the amount of enzyme required to increase fluorescence 1.5 RFUs per sec at 37°C using 20 pmol of RNaseAlert® probe coupled to 1,000 pmol of a complementary oligonucleotide as substrate.

Ambion™ Recombinant RNase A (Invitrogen™)

Ambion® Recombinant RNase A for the production of plasmid DNA that is substantially free of host RNA is now available for research applications. For large batch sizes, the use of RNase is still the only effective technique applicable to remove host RNA. Other methods such as selective precipitation, gel filtration, chromatography, and endogenous E. coli RNase digestion have only been effective for small-scale or bench-scale purification. This new product was designed specifically to minimize the risk of introducing pathogens into bioprocessing. Recombinant RNase A is rigorously tested for contaminating nonspecific endonuclease, exonuclease, and protease activity.

Shrimp Alkaline Phosphatase (SAP) (Applied Biosystems™)

Proven Performance – the Phosphatase benchmark
•100% heat-inactivated in 5 min at 65°C
•Significantly improved storage stability at lower temperatures (see Fig. 1 and 2) 
•Very high specific activity (see Fig. 3)
•Removes 5'-phosphates from DNA, RNA, dNTPs, and proteins 
•Purified from a recombinant source
•May be added directly to restriction enzyme digests 
•No vector purification necessary 
•Requires no supplemental zinc or other additives for activity 
•Works direct in many different buffers 
•Easy treatment of unincorporated dNTPs in PCR products prior to DNA sequencing or SNP analysis

USB Shrimp Alkaline Phosphatase (SAP)
Shrimp Alkaline Phosphatase (SAP) is a high specific activity, heat-labile alkaline phosphatase  purified from a recombinant source and originally isolated from Pandalus borealis (arctic shrimp).  SAP is useful in many molecular biology applications such as the dephosphorylation of phosphorylated ends of DNA or RNA for subsequent use in cloning or end-labeling of probes. In cloning, dephosphorylation prevents relegation of linearized plasmid DNA. SAP may also be used to treat unincorporated dNTPs in PCR reactions to prepare templates for DNA sequencing or SNP analysis.

Shrimp Alkaline Phosphatase has approximately the same specific activity as Calf Intestinal Alkaline Phosphatase (CIAP), and like CIAP, is active in virtually all restriction enzyme reaction buffers. Unlike CIAP, Shrimp Alkaline Phosphatase is completely and irreversibly inactivated by heating reactions at 65°C for 15 min.

Shrimp Alkaline Phosphatase is particularly useful in preparing PCR products for applications involving sequencing, SNP analysis or labeling methods. Typically, excess dNTPs remaining after PCR interfere with subsequent enzymatic reactions involving DNA synthesis. SAP dephosphorylates all of the remaining dNTPs from the PCR mixture in one easy step.

We are pleased to be offering a recombinant version of our phosphatase benchmark. Recombinant SAP eliminates the dependence on animal sourcing and offers the added benefits of increased storage stability and batch to batch consistency while providing exceptional enzymatic activity and 100% heat inactivation.

Properties:
Molecular Weight: Homodimer. Monomer is 55 kDa as determined by amino acid sequence.
Optimum pH: 10.4 in glycine buffer and pH 8.0 in Tris buffer.
Optimum Temperature: 37°C
Heat-Inactivation: 65°C for 15 min.
Inhibitors: 10mM DTT, 0.1% β-ME
Reaction Conditions: Active in NaCl, KCl. Requires Mg2+ for highest activity.

Source:
Recombinant

Purity:
Tested for contaminating endonucleases, exonucleases, and ribonucleases.

Storage Buffer:
25mM Tris-HCl (pH 7.5), 1mM MgCl2, 50% glycerol.

Assay Conditions:
The reaction mixture contains 100mM glycine, pH 10.4, 1mM MgCl2, 1mM ZnCl2, 10mM p-nitrophenyl phosphate, and 0.001-0.1 units of Shrimp Alkaline Phosphatase (SAP). The change in absorbance at 405 nm is monitored (3050 µL reaction volume).

Unit Definition:
One unit is the amount of enzyme which catalyzes the hydrolysis of 1 µmol of p-nitrophenyl phosphate per min in glycine buffer (pH 10.4) at 37°C.

Concentration:
1 unit/µL

Functional Test:
Dephosphorylation of restriction enzyme digested plasmids (5 – 20 pmol of 5'-ends, 0.1 -0.5 units/pmol 5'-ends). Reduces religation to < 0.5% compared to the untreated control.

PROTOCOL FOR DEPHOSPHORYLATION OF NUCLEOTIDES AND DEGRADATION OF PRIMERS PRIOR TO SEQUENCING REACTIONS OR SNP ANALYSES:
Please refer to the USB ExoSAP-IT protocol, the benchmark in PCR clean-up.

The purchase of ExoSAP-IT provides a license to the methods of PCR clean up using Exonuclease I and SAP.

Functionally Tested 10X SAP Reaction Buffer (Included, PN 70103):
200mM Tris-HCl (pH 8.0), 100mM MgCl2.

Functionally Tested SAP Dilution Buffer (1 ml included, PN 72761):
50mM Tris-HCl (pH 8.0).

References:
1. RUAN, C. C., SAMOLS, S. B. AND FULLER, C. W. (1990) Comments 17, (No.1), United States Biochemical Corporation, Cleveland, OH.
2. WERLE, E., SCNEIDER C., RENNER, M., VÖLKER, M. AND FIEHN, W. (1994) Nucleic Acids Res. 22, 4354-4355.
3. HANKE, M. AND WINK, M. (1994) BioTechniques17, 858-860.

TURBO DNA-free™ Kit (Invitrogen™)

The TURBO DNA-free™ Kit contains reagents for the efficient, complete digestion of DNA along with the removal of the enzyme and divalent cations post-digestion.

Note: if you would like to purchase the enzyme alone, without the inactivation and cation removal reagents, please see TURBO™ DNAase.

Features of the TURBO DNA-free™ Kit include:

• Hyperactive TURBO™ DNase is a catalytically superior enzyme compared to wild type DNase I
• Removes trace quantities of DNA that can interfere with RT-PCR
• Reagent included to completely remove DNase without phenol treatment or heating

The best method for genomic DNA removal prior to RT-PCR
TURBO™ DNase is a recombinant, engineered form of DNase I that is much more efficient than wild type DNase I in digesting away trace amounts of unwanted DNA. TURBO™ DNase binds DNA substrates 6-fold more tightly than traditional DNase I, making this enzyme the tool of choice for clearing residual DNA that can generate a false positive signal in RT-PCR applications. TURBO™ DNase now includes an enhancer that increases the effectiveness by two orders of magnitude.

Efficient DNase and divalent cation removal without organic extraction or precipitation
Conventional DNase treatment of RNA samples prior to RT-PCR typically call for inactivation of the DNase by phenol:CHCl3 extraction or heating followed by a precipitation step to concentrate the RNA. Phenol:CHCl3 extractions can be cumbersome and time-consuming. Heating the sample to inactivate DNase can lead to chemical degradation of the RNA by divalent cations present in the DNase buffer. The TURBO DNA-free™ Kit circumvents these problems using a novel DNase Inactivation Reagent. In addition to removing the TURBO™ DNase from the reaction, the Inactivation Reagent also binds and removes divalent cations from the TURBO™ DNase Reaction Buffer.

Uracil-DNA Glycosylase (1 U/µL) (Thermo Scientific™)

Thermo Scientific Uracil-DNA Glycosylase (UDG, UNG) catalyzes the hydrolysis of the N-glycosylic bond between uracil and sugar, leaving an apyrimidinic site in uracil-containing single or double-stranded DNA (see Figure 1 in Supporting Data). The enzyme shows no activity on RNA.

Highlights

Active in Thermo Scientific buffers for restriction enzymes and thermophilic polymerases

Applications

• Control of carry-over contamination in PCR
• Glycosylase mediated single nucleotide polymorphism detection (GMPD)
• Site-directed mutagenesis
• As a probe for protein-DNA interaction studies
• SNP genotyping
• Cloning of PCR products
• Generation of single strand overhangs of PCR products and cDNA

Note

The abasic sites formed in DNA by Uracil-DNA Glycosylase may be subsequently cleaved by heat, alkali-treatment or endonucleases that cleave specifically at abasic sites. UDG (UNG) is active in the presence or absence of divalent cations.

Use of this enzyme in certain applications may be covered by patents and may require a license.

Ambion™ RNase A, affinity purified, 1 mg/mL (Invitrogen™)

Ambion® RNase A is an endonuclease that specifically cleaves 3' of U and C residues. Affinity Purified RNase A is intended for critical applications when the absence of DNase and other nonspecific nuclease activities is essential. Supplied in one tube containing 200 µg (1 mg/mL). Note: This preparation contains RNase B, a carbohydrate isoform of RNase A. RNase A is rigorously tested for contaminating nonspecific endonuclease, exonuclease, and protease activity.

DNase I, RNase-free, HC (50 U/µL) (Thermo Scientific™)

Thermo Scientific DNase I, RNase-free is an endonuclease that digests single- and double-stranded DNA. It hydrolyzes phosphodiester bonds producing mono- and oligodeoxyribonucleotides with 5'-phosphate and 3'-OH groups.

The enzyme activity is strictly dependent on Ca2+ and is activated by Mg2+ or Mn2+ ions.

In the presence of Mg2+, DNase I cleaves each strand of dsDNA independently in a statistically random fashion. In the presence of Mn2+, the enzyme cleaves both DNA strands at approximately the same site, producing DNA fragments with blunt-ends or with overhang termini of only one or two nucleotides.

Highlights

• Recombinant enzyme
• Purified from non-animal host with a lower level of intrinsic RNases

Applications

• Preparation of DNA-free RNA
• Removal of template DNA following in vitro transcription
• Preparation of DNA-free RNA prior to RT-PCR and RT-qPCR
• DNA labeling by nick-translation in conjunction with DNA Polymerase I
• Studies of DNA-protein interactions by DNase I, RNase-free footprinting
• Generation of a library of randomly overlapping DNA inserts. Reaction buffer containing Mn2+ is used

Note

DNase I is sensitive to physical denaturation. Mix gently by inverting the tube. Do not vortex.