Uracil DNA Glycosylase from Escherichia coli

Eliminates carry-over contamination that can result in false positives in PCR reactions. UDG catalyzes the removal of uracil residues from both single- and double-stranded DNA, but not RNA. This reaction leaves the DNA sugar-phosphodiester backbone intact. The resulting DNA is not suitable for use as a hybridization target or as a template for DNA polymerases.

Uracil-N-glycosylase (UNG) belongs to the family of highly conserved Uracil DNA glycosylases (UDGs) and is present in a large number of eukaryotes, bacteria, and DNA viruses.

Uracil-N-glycosylase (UNG) belongs to the family of highly conserved Uracil DNA glycosylases (UDGs) and is present in a large number of eukaryotes, bacteria, and DNA viruses.

UNG removes uracil resulting from deamination of cytosine or replicative incorporation of dUMP instead of dTMP by cleaving the N-glycosylic bond between uracil and deoxyribose, leaving an apyrimidinic site in uracil-containing single or double-stranded DNA. The removal of uracil by UDG is accomplished by a base excision repair pathway.

The human UNG gene encodes two isoforms: hUNG1 isoform (304 amino acids) and hUNG2 isoform (313 amino acids). hUNG1 is widely expressed with the highest expression in skeletal muscle and contains a mitochondrial leader peptide on its N-terminus. hUNG2 is a nuclear protein highly expressed in tissues containing proliferating cells. Defects in UNG gene are a cause of immunodeficiency with hyper-IgM type 5 syndrome (HIGM5).

Solution in 30 mM Tris-HCl, pH 7.5, 1 mM DTT, 0.05% (w/v) Tween-20, 1 mM EDTA, 150 mM NaCl, 50% (v/v) glycerol.

One unit catalyzes the release of 1 nmol of free uracil from ³H-poly(dU) in 1hr at 37 °C.