Product Class: Other

Exonuclease T
NEB4 Gray property icon for cloned at NEB recombinant Gray property icon for incubation temperature 25° Gray property icon for heat inactivation 65°

Product Introduction

Exonuclease I (E.coli), Thermostable Exonuclease I, Exonuclease T mechanism


  • Also known as RNase T
  • Single-stranded (ssDNA or RNA) specific exonuclease
  • Catalyzes the removal of nucleotides from linear single-stranded DNA or RNA in the 3' to 5' direction
  • Need help finding the right exonuclease for your experiments? Try Exo Selector 

Exonuclease T can be used for:

  • Removal of 3' overhangs of double-stranded DNA to generate blunt-ends*
  • Removal of single-stranded primers in PCR reactions prior to DNA sequencing or SNP analysis
  • Removal of single-stranded primers for nested PCR reactions
  • Removal of single-stranded DNA, leaving behind double-stranded DNA in the sample
  • Not sure which RNase to choose? Learn more about the different RNases offered by NEB.

*sequence-dependent

Bioz Badge Exists : True
Catalog # Size Concentration
M0265S 250 units 5000 units/ml
M0265L 1250 units 5000 units/ml

Product Information

Description

Exonuclease T (Exo T), also known as RNase T, is a single-stranded RNA (1,2) or DNA (3,4) specific nuclease that requires a free 3´ terminus and removes nucleotides in the 3´→ 5´ direction. Exonuclease T can be used to generate blunt ends from RNA (5) or DNA molecules that have 3´ extensions (4).

Product Source

Exonuclease T is overexpressed and purified as a C-terminal fusion to maltose-binding protein (MBP). MBP is removed from Exonuclease T by Factor Xa cleavage and Exonuclease T is then purified away from Factor Xa and MBP. Exonuclease T cleaved from MBP has an additional amino acid on the N-terminus and a Phe instead of a Met (i.e., Glu-Phe-Exo T instead of Met-Exo T).
This product is related to the following categories:
RNases,
Epitranscriptome Analysis,
Exonucleases and Non-specific Endonucleases,

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 release 1 nmol of single dT nucleotides from 50 pmol of Fam-labeled polythymidine substrate in 30 minutes at 25°C.

Reaction Conditions

1X NEBuffer™ 4
Incubate at 25°C

1X NEBuffer™ 4
50 mM Potassium Acetate
20 mM Tris-acetate
10 mM Magnesium Acetate
1 mM DTT
(pH 7.9 @ 25°C)

Activity in NEBuffers

NEBuffer™ 1: 100%
NEBuffer™ 2: 75%
NEBuffer™ 3: 25%

Storage Buffer

10 mM Tris-HCl
50 mM KCl
1 mM DTT
0.1 mM EDTA
200 µg/ml BSA
50% Glycerol
pH 7.4 @ 25°C

Heat Inactivation

65°C for 20 minutes

Product Notes

  1. Exonuclease T has a different activity on RNA vs. DNA. For RNA, 1 unit of Exonuclease T is required to completely digest 1.0 pmol of rA20 under standard reaction conditions as measured by gel electrophoresis.
  2. Single stranded RNA molecules containing C residues at its 3'-terminus might be difficult to digest with Exonuclease T.
  3. Exonuclease T removes ssDNA extensions but does not work well when two cytosine nucleotides are in a row.  “Although RNase T appears to bind up to 10 nucleotides in its active site, its specificity is defined largely by the last 4 residues. A single 3'-terminal C residue can reduce RNase T action by >100-fold, and 2-terminal C residues essentially stop the enzyme.” (PMID: 12050169 DOI: 10.1074/jbc.M204252200)

References

  1. Deutscher, M. P., Marlor, C. W. and Zaniewski, R. (1984). Proc. Natl. Acad. Sci. USA. 81, 4290–4293.
  2. Deutscher, M. P. and Marlor, C. W. (1985). J. Biol. Chem. 260, 7067–7071.
  3. Viswanathan, M., Dower, K. D. and Lovett, S. T. (1998). J. Biol. Chem. 273, 35126–35131.
  4. Zuo, Y. and Deutscher, M. P. (1999). Nucleic Acid Res. 27, 4077–4082.
  5. Zeng, Y. and Cullen, B. R. (2004). Nucleic Acid Res. 32, 4776–4780.
  6. Zuo, Y. and Deutscher, M.P. (2002). J. Biol. Chem. 277, 29654-61.

Tools & Resources

Selection Charts

Web Tools

FAQs & Troubleshooting

FAQs

  1. Is Exonuclease T salt tolerant?

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 busdev@neb.com.

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.

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