Thermo Scientific™

Exonuclease III (200 U/µL)

Catalog number:  EN0191

Related applications:


| PCR Cloning

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Thermo Scientific Exonuclease III (ExoIII) exhibits four catalytic activities. The 3'→5' exodeoxyribonuclease activity of ExoIII is specific for double-stranded DNA. ExoIII degrades dsDNA from blunt ends, 5'-overhangs or nicks, releases 5'-mononucleotides from the 3'-ends of DNA strands and produces stretches of single-stranded DNA. It is not active on 3'-overhang ends of DNA that are at least four-bases long and do not carry a 3'-terminal C-residue on single-stranded DNA, or on phosphorothioate-linked nucleotides.

ExoIII 3'-phosphatase activity removes the 3'-terminal phosphate, generating a 3'-OH group. ExoIII Rnase H activity exonucleolytically degrades the RNA strand in RNA-DNA hybrids. ExoIII apurinic/apyrimidinic-endonuclease activity cleaves phosphodiester bonds at apurinic or apyrimidinic sites to produce 5'-termini that are base-free deoxyribose 5'-phosphate residues.


• Active in restriction enzyme buffers


• Creation of unidirectional deletions in DNA fragments in conjunction with S1 Nuclease
• Generation of a single-stranded template for dideoxy-sequencing of DNA
• Site-directed mutagenesis
• Cloning of PCR products
• Preparation of strand-specific probes


The rate of DNA digestion by ExoIII depends upon temperature, salt concentration, and the molar ratio of DNA to enzyme in the reaction mixture . Optimal reaction conditions should be determined experimentally.
For Research Use Only. Not for use in diagnostic procedures.


Product Type: Exonuclease III
Concentration: 200 U/µL
Quantity: 4000 unit
Enzyme: Exonuclease
Compatible Buffer: Enzyme Buffer