Product Class: Other

Exonuclease III (E. coli)
NEB1 recombinant 37 70 Heat

Product Introduction

  • Double-stranded DNA specific exonuclease
  • Initiates at the 3' termini of linear double-stranded DNA with 5' overhangs or blunt ends and 3' overhangs containing less than four bases
  • Initiates at nicked sites in double-stranded DNA
  • Catalyzes the removal of nucleotides from linear or nicked double-stranded DNA in the 3' to 5' direction
  • Need help finding the right exonuclease for your experiments? Try Exo Selector 

Exonuclease III is ideal for:

  • Site-directed mutagenesis
  • Preparation of single-stranded DNA for dideoxy sequencing
  • Preparation of nested deletions in double-stranded DNA
Catalog # Size Concentration
M0206S 5000.0 units 100000 units/ml
M0206L 25000.0 units 100000 units/ml

Product Information

Description

Catalyzes the stepwise removal of mononucleotides from 3´-hydroxyl termini of duplex DNA (1). A limited number of nucleotides are removed during each binding event, resulting in coordinated progressive deletions within the population of DNA molecules (2). Exonuclease III has also been reported to have RNase H, 3´-phosphatase and AP-endonuclease activities (1).

The preferred substrates are blunt or recessed 3´-termini, although the enzyme also acts at nicks in duplex DNA to produce single-strand gaps. 3´-protruding termini are resistant to cleavage; the degree of resistance depends on the length of the extension,with extensions 4 bases or longer being essentially resistant to cleavage.

Exonuclease III activity depends partially on helical structure (4) and displays sequence dependence (C>A=T>G; ref. 5). Temperature, salt concentration and the ratio of enzyme to DNA greatly affect enzyme activity, requiring reaction conditions to be tailored to specific applications. 

Product Source

An E. coli strain that carries the cloned Exonuclease III gene from E. coli.
This product is related to the following categories:
Exonucleases and Non-specific Endonucleases Products
This product can be used in the following applications:
Polymerases for DNA Manipulation

Reagents Supplied

Reagents Supplied

The following reagents are supplied with this product:

NEB # Component Name Component # Stored at (°C) Amount Concentration

Properties & Usage

Unit Definition

One unit is defined as the amount of enzyme required to produce 1 nmol of acid-soluble total nucleotide in a total reaction volume of 50 μl in 30 minutes at 37°C in 1X NEBuffer 1 with 0.15 mM sonicated duplex [3H]-DNA.

Reaction Conditions

1X NEBuffer™ 1
Incubate at 37°C

1X NEBuffer™ 1
10 mM Bis-Tris-Propane-HCl
10 mM MgCl2
1 mM DTT
(pH 7 @ 25°C)

Storage Buffer

5 mM KPO4
200 mM KCl
5 mM β-ME
0.05 mM EDTA
200 µg/ml BSA
50% Glycerol
pH 6.5 @ 25°C

Heat Inactivation

70°C for 20 minutes

Specific Activity

150,000 units/mg

Application Features

  • Unidirectional nested deletions (3)
  • Site-directed mutagenesis (6)
  • Preparation of strand-specific probes (2)
  • Preparation of single-stranded substrates for dideoxy sequencing (7)

Product Notes

  1. Phosphorothioate linkages are not cleaved by Exonuclease III. Unidirectional deletions can also be created by protecting one terminus by incorporation of α-phosphorothioate-containing nucleotide.
  2. The activity of Exonuclease III in various buffers is listed below:

    • NEBuffer 1 - 100%
    • NEBuffer 2 - 75%
    • NEBuffer 3 -25%
    • NEBuffer 4 - 75%
    • CutSmart – 100%

References

  1. Rogers, G.S. and Weiss, B. (1980). L. Grossman and K. Moldave(Ed.), Methods Enzymol.. 65, 201-211. New York: Academic Press.
  2. Sambrook, J., Fritsch, E.F. and Maniatis, T. (1989). Molecular Cloning: A Laboratory Manual (2nd. Ed.). 5.84-5.85.
  3. Henikoff, S. (1984). Gene. 28, 351-359.
  4. Richardson, C.C. et al. (1964). J. Biol. Chem. 239, 251-258.
  5. Linxweiler, W. and Horz, W. (1982). Nucl. Acids Res. 10, 4845-4859.
  6. Vandeyar, M.A. (1988). Gene. 65, 129-133.
  7. Guo, L.H. and Wu, R. (1982). Nucl. Acids Res.. 10, 2065-2084.
  8. Putney, S., Benkovic, S. and Schimmel, P. (1981). Proc. Natl. Acad. Sci. USA. 78, 7350-7354.

Protocols, Manuals & Usage

Protocols

  1. Protocol for Exonuclease III (M0206)

Tools & Resources

Selection Charts

Web Tools

Research Posters

FAQs & Troubleshooting

FAQs

  1. What is the activity of M0206 Exonuclease III in various NEB buffers?
  2. How does T5 Exonuclease differ from Exonuclease III (NEB# M0206)?
  3. How Does T7 Exonuclease differ from Exonuclease III (NEB# M0206)?
  4. Will Exonuclease III work in rCutSmart buffer?
  5. Can Exonuclease I be used with a double stranded exonuclease to clean up plasmid preparations?

Quality, Safety & Legal

Quality Assurance Statement

Quality Control tests are performed on each new lot of NEB product to meet the specifications designated for it. Specifications and individual lot data from the tests that are performed for this particular product can be found and downloaded on the Product Specification Sheet, Certificate of Analysis, data card or product manual. Further information regarding NEB product quality can be found here.

Specifications

The Specification sheet is a document that includes the storage temperature, shelf life and the specifications designated for the product. The following file naming structure is used to name these document files: [Product Number]_[Size]_[Version]

Certificate Of Analysis

The Certificate of Analysis (COA) is a signed document that includes the storage temperature, expiration date and quality controls for an individual lot. The following file naming structure is used to name these document files: [Product Number]_[Size]_[Version]_[Lot Number]

Safety DataSheets

The following is a list of Safety Data Sheet (SDS) that apply to this product to help you use it safely.

Legal and Disclaimers

Products and content are covered by one or more patents, trademarks and/or copyrights owned or controlled by New England Biolabs, Inc (NEB). The use of trademark symbols does not necessarily indicate that the name is trademarked in the country where it is being read; it indicates where the content was originally developed. The use of this product may require the buyer to obtain additional third-party intellectual property rights for certain applications. For more information, please email [email protected].

This product is intended for research purposes only. This product is not intended to be used for therapeutic or diagnostic purposes in humans or animals.

New England Biolabs (NEB) is committed to practicing ethical science – we believe it is our job as researchers to ask the important questions that when answered will help preserve our quality of life and the world that we live in. However, this research should always be done in safe and ethical manner. Learn more.