Exonuclease I (E. coli)

Description

Catalyzes the removal of nucleotides from single-stranded DNA in the 3' to 5' direction.

Highlights

  • Isolated from a recombinant source
  • 3' → 5' single strand exonuclease
  • Supplied with 10X Reaction Buffer

Product Source

An E. coli strain that carries the cloned Exo I gene from E. coli NM554.

Reagents Supplied

The following reagents are supplied with this product:

Store at (°C)Concentration
Exonuclease I Reaction Buffer-2010X

Advantages and Features

Applications

  • Exonuclease I degrades excess single-stranded primer oligonucleotide from a reaction mixture containing double-stranded extension products

Properties and Usage

Unit Definition

One unit is defined as the amount of enzyme that will catalyze the release of 10 nmol of acid-soluble nucleotide in a total reaction volume of 50 μl in 30 minutes at 37°C in 1X Exonuclease I Reaction Buffer with 0.17 mg/ml single-stranded [3H]-DNA.

Reaction Conditions

1X Exonuclease I Reaction Buffer
Incubate at 37°C

1X Exonuclease I Reaction Buffer:
67 mM Glycine-KOH
6.7 mM MgCl2
10 mM β-ME
pH 9.5 @ 25°C

Usage Concentration

10,000 units/ml

Storage Temperature

-20°C

Storage Conditions

10 mM Tris-HCl
100 mM NaCl
5 mM β-ME
0.5 mM EDTA
100 μg/ml BSA
50% Glycerol
pH 7.5 @ 25°C

Heat Inactivation

80°C for 20 min

References

  1. Lehman and Nussbaum (1964). J. Biol. Chem. 239
  2. Kusher, et al. (1971). Proc. Natl. Acad. Sci. USA. 68
  3. Kusher et al. (1972). Proc. Natl. Acad. Sci. USA. 69, 1366.
  4. Goldmark and Linn (1972). J. Biol. Chem. 247
  5. Rosamond et al. (1979). J. Biol. Chem. 254

FAQs

  1. Can Exonuclease I be used to remove primers from amplification reactions?
  2. Will Exonuclease I degrade RNA?
  3. Can Exonuclease I be used to blunt DNA?
  4. Can Exonuclease I be heat inactivated?
  5. Can Exonuclease I be used with a double stranded exonuclease to clean up plasmid preparations?
  6. Will Exonuclease I work in other buffers?

Datacards

The Product Summary Sheet, or Data Card, includes details for how to use the product, as well as details of its formulation and quality controls. The following file naming structure is used to name the majority of these document files: [Catalog Number]Datasheet-Lot[Lot Number]. For those product lots not listed below, please contact NEB at info@neb.com or fill out the Technical Support Form for appropriate document.

Selection Charts

Interactive Tools

Application Notes

Quality Control

Quality Control Assays

The following Quality Control Tests are performed on each new lot and meet the specifications designated for the product. Individual lot data can be found on the Product Summary Sheet/Datacard or Manual which can be found in the Supporting Documents section of this page. Further information regarding NEB product quality can be found here.
  • Endonuclease Activity (Nicking):
    The product is tested in a reaction containing a supercoiled DNA substrate. After incubation for 4 hours the percent converted to the nicked form is determined by agarose gel electrophoresis.
  • Exonuclease Activity (Radioactivity Release):
    The product is tested in a reaction containing a radiolabeled mixture of single and double-stranded DNA. After incubation for 4 hours the exonuclease activity is determined by the % release of radioactive nucleotides.
  • Protein Purity (SDS-PAGE):
    The physical purity is assessed by comparing contaminating protein bands in a concentrated sample to the protein of interest band in a sample of known dilution. The purity is determined by SDS-PAGE.

Safety Data Sheet

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

Datacards

The Product Summary Sheet, or Data Card, includes details for how to use the product, as well as details of its formulation and quality controls. The following file naming structure is used to name the majority of these document files: [Catalog Number]Datasheet-Lot[Lot Number]. For those product lots not listed below, please contact NEB at info@neb.com or fill out the Technical Support Form for appropriate document.