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Uracil-DNA Glycosylase (UNG), Cod
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  • Degrades uracil-containing DNA, but not RNA or thymidine-containing DNA 
  • Prevents carryover contamination in PCR, qPCR  and qRT-PCR
  • Effective with only a 5 minute incubation step
  • Complete, irreversible heat-inactivation

Uracil-DNA Glycosylase (UNG), Cod

Uracil-DNA Glycosylase (UNG), Cod is a thermolabile recombinant enzyme produced in E. coli (ung-) by a modified ung gene derived from Atlantic Cod. It degrades uracil-containing single- and double-stranded DNA, but not RNA or thymidine-containing DNA, by hydrolyzing the N-glycosidic bond between deoxyribose sugar and the base in uracil. This generates alkaline-sensitive apyramidinic sites in the DNA that will be cleaved upon a combination of alkaline conditions and high temperature.

Pretreatment of samples with UNG prevents PCR carryover contamination in labs that substitute dUTP in place of dTTP during all amplification reactions. PCR products containing uracil become substrates for UNG and will be degraded if they are present in subsequent reaction mixtures subjected to UNG treatment. Only DNA templates containing thymidine are not degraded by the treatment and will be amplified.

Recombinant cod UNG is irreversibly heat inactivated, which enables long-term storage and subsequent analysis of post-PCR amplicons in applications such as cloning and sequencing. AMRESCO’s UNG is compatible with PCR, qPCR and one-step qRT-PCR and works in all commercially available master mixes. All amplification reactions must use dUTP containing dNTP mixtures in order for the UNG decontamination method to be effective.

Uracil-DNA Glycosylase (UNG), Cod treatment specifically degrades dUTP-containing DNA in spiked PCR reactions and inactivates completely to allow subsequent synthesis of new dUTP-containing  amplicon.  Two PCR reactions were prepared with normal dTTP-containing DNA template and then spiked with a dUTP-containing amplicon from a previous PCR reaction.  One PCR reaction was treated with UNG (1B1634) for 5 minutes at room temperature, while the other tube was left untreated.  The treated and untreated samples were then immediately amplified by PCR, with the initial denaturation cycle serving as the heat inactivation step for the UNG treated sample.  Following amplification, the PCR products with incorporated dUTP were analyzed by gel.  The amplicons were stored at room temperature for 4 days and then analyzed by gel again.  In the UNG treated sample, only one band was present due to effective degradation of the dUTP DNA.  The dUTP DNA synthesized from dTTP template after UNG heat inactivation remained stable, even when stored at room temperature.
DNase (P/F)
Functional Test (P/F)
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