Thermo Scientific™

Fast DNA End Repair Kit

Catalog number:  K0771

Related applications:

Restriction Enzyme Cloning

| PCR Cloning

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Thermo Scientific Fast DNA End Repair Kit is used for blunting and phosphorylation of DNA ends in just 5 minutes for subsequent use in blunt-end ligation.

All components of the kit contain premixed reagents to reduce pipetting steps and provide convenience. The End Repair Enzyme Mix contains an optimized mixture of T4 DNA Polymerase and Klenow Fragment to achieve highly effective blunting of fragmented DNA, and T4 Polynucleotide Kinase (PNK) for efficient phosphorylation of DNA ends. The 10X End Repair Reaction Mix contains an optimized reaction buffer, ATP, and dNTPs.

Samples such as fragmented genomic DNA (restriction enzyme digested, nebulized or sonicated), restriction enzyme digested plasmid DNA, double stranded cDNA, and PCR products containing dA overhangs are all compatible with the kit.


During the DNA end repair reaction, fragmented DNA is converted into blunt-end DNA containing a 5'-phosphate and 3'-hydroxyl groups. The 5'→3' polymerase activity of the End Repair Enzyme Mix fills-in 5' protruded DNA ends while 3'→5' exonuclease activity removes 3'-overhangs. T4 PNK adds 5'-phosphates to ends of unphosphorylated DNA fragments, such as PCR products. (see Table 1 and Figure 1 below).


Efficient - blunting and phosphorylation of 0.5 to 5 µg DNA
Fast—reaction is completed in 5 minutes
Convenient—reaction components are premixed to reduce pipetting steps


• Blunting and phosphorylation of double-stranded DNA (nebulized DNA, sonicated DNA, restriction enzyme digested DNA, cDNA, PCR products)


• End Repair Enzyme Mix
• 10X End Repair Reaction Mix

Related Products
CloneJET PCR Cloning Kit
For Research Use Only. Not for use in diagnostic procedures.


Enzyme: DNA Polymerase, T4 Polynucleotide Kinase