Product Class: Other

T4 DNA Ligase
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Item# Description List Price Web Price Qty
M0202L T4 DNA Ligase - 100,000 units $371.00
M0202M T4 DNA Ligase (2,000,000 units/ml) - 100,000 units $371.00
M0202S T4 DNA Ligase - 20,000 units $93.00
M0202T T4 DNA Ligase (2,000,000 units/ml) - 20,000 units $93.00
*On-line ordering is for Canadian customers only. Web pricing is applicable only to orders placed online at

Looking for T4 DNA Ligase alternatives?  Try Salt-T4 or Hi-T4 DNA Ligases

Product Introduction

  • Catalyzes the formation of a phosphodiester bond between juxtaposed 5' phosphate and 3' hydroxyl termini in duplex DNA or RNA.
  • This enzyme will join blunt end and cohesive end termini as well as repair single stranded nicks in duplex DNA and some DNA/RNA hybrids (1).
  • T4 DNA ligase will seal nicks for these DNA substrates.
  • The industry standard for performance and quality
  • T4 DNA Ligase variant products include Salt-T4, Hi-T4, Instant Sticky-end Ligase Master Mix and Blunt/TA Ligase Master Mix
  • Not sure which ligase to choose?  Refer to our DNA and RNA Ligase Properties Chart
Bioz Badge Exists : True

Product Information



  • Isolated from a recombinant source
  • Supplied with 10X Reaction Buffer

For details on NEB's quality controls for DNA ligases, visit our Ligase Quality page.

T4 DNA Ligase Competitor Study - Nuclease Contamination
T4 DNA Ligase Competitor Study- Nuclease Contamination
T4 DNA Ligase from multiple suppliers was tested in reactions containing a fluorescent labeled single stranded, double stranded blunt, 3’overhang or 5’ overhang containing oligonucleotides. The percent degradation by contaminating nucleases is determined by capillary electrophoresis and peak analysis. The resolution is at the single nucleotide level.

Product Source

Purified from E. coli C600 pcl857 pPLc28 lig8 (2).

Advantages and Features

Application Features

  • Cloning of restriction fragments
  • Joining linkers and adapters to blunt-ended DNA

Properties & Usage

    Unit Definition

    One unit is defined as the amount of enzyme required to give 50% ligation of HindIII fragments of λ DNA (5´ DNA termini concentration of 0.12 µM, 300- µg/ml) in a total reaction volume of 20 μl in 30 minutes at 16°C in 1X T4 DNA Ligase Reaction Buffer.

    400,000 cohesive end units/ml and 2,000,000 cohesive end units/ml

    Reaction Conditions

    1X T4 DNA Ligase Reaction Buffer
    Incubate at 16°C

    1X T4 DNA Ligase Reaction Buffer
    50 mM Tris-HCl
    10 mM MgCl2
    1 mM ATP
    10 mM DTT
    (pH 7.5 @ 25°C)

    Storage Temperature


    Storage Conditions

    10 mM Tris-HCl
    50 mM KCl
    1 mM DTT
    0.1 mM EDTA
    50% Glycerol
    pH 7.4 @ 25°C

    Heat Inactivation

    65°C for 10 min

    Product Notes

    1. ATP is an essential cofactor for the reaction. This contrasts with E. coli DNA ligase which requires NAD.
    2. To dilute T4 DNA Ligase that will subsequently be stored at -20°C, 50% glycerol storage buffer (Diluent Buffer A,NEB #B8001S) should be used; to dilute for immediate use, 1X T4 DNA Ligase Reaction Buffer can be used.
    3. Ligation can also be performed in any of the four restriction endonuclease NEBuffers or in T4 Polynucleotide Kinase Buffer if they are supplemented with 1 mM ATP.
    4. Room Temperature Ligation
      For convenience, ligations may be done at room temperature (20-25°C). For cohesive (sticky) ends, use 1 µl of T4 DNA Ligase in a 20 µl reaction for 10 minutes. For blunt ends, use 1 µl of T4 DNA Ligase in a 20 µl reaction for 2 hours or 1 µl high concentration T4 DNA Ligase for 10 minutes. Alternatively, NEB's Quick Ligation Kit (#M2200S) [30 reactions] or (#M2200L) [150 reactions]) is uniquely formulated to ligate both blunt and cohesive (sticky) ends in 5 minutes at room temperature.


    1. Engler, M.J. and Richardson, C.C. (1982). P.D. Boyer(Ed.), 5, 3. San Diego: Academic Press.
    2. Remaut, E., Tsao, H. and Fiers, W. (1983). Gene. 22, 103-113.
    3. Sambrook, J., Fritsch, E.F. and Maniatis, T. (1989). Molecular Cloning: A Laboratory Manual, (2nd Ed.). 1.53-1.73.

    Protocols, Manuals & Usage


    1. Ligation Protocol with T4 DNA Ligase (M0202)
    2. Golden Gate (24 Fragment) Assembly Protocol

    Usage & Guidelines

    • Activity of DNA Modifying Enzymes in CutSmart® Buffer
    • Tips for Maximizing Ligation Efficiencies

    Application Notes


    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 [email protected] or fill out the Technical Support Form for appropriate document.)

    Tools & Resources

    Selection Charts

    • Buffer and Diluent Formulation Table
    • DNA Ligase Selection Chart
    • Properties of DNA and RNA Ligases
    • Substrate-based Ligase Selection Chart

    Web Tools

    FAQs & Troubleshooting


    1. What are some potential problems with the ligation reaction using T4 DNA Ligase that can lead to transformation failure?
    2. What are some other problems that should be considered when troubleshooting a transformation problem?
    3. What problems can be encountered in the restriction digest that can cause ligation using T4 DNA Ligase or subsequent transformation to fail?
    4. What controls should be run to test the cells and DNA when using T4 DNA Ligase?
    5. When should T4 DNA Ligase be the enzyme of choice?
    6. Can the T4 DNA Ligase be used with the Quick Ligase buffer?
    7. What is the definition of a Weiss Unit and a Cohesive End Unit?
    8. What is the difference between the two definitions and why does NEB use the Cohesive End Unit?
    9. How much DNA should be used in a ligation using T4 DNA Ligase?
    10. Can T4 DNA Ligase be used in other NEBuffers, including CutSmart?
    11. Can T4 DNA Ligase be heat inactivated?


    • Troubleshooting Tips for Ligation Reactions

    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.


    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

    This product is covered by one or more patents, trademarks and/or copyrights owned or controlled by New England Biolabs, Inc (NEB).

    While NEB develops and validates its products for various applications, the use of this product may require the buyer to obtain additional third party intellectual property rights for certain applications.

    For more information about commercial rights, please contact NEB's Global Business Development team at [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.