The Uracil Cleavage System provides two enzymes, which, when added sequentially to a reaction containing a synthetic DNA fragment containing a deoxy-uracil, generate a single nucleotide gap at the location of the uracil residue. The system consists of two individual enzyme components, Uracil DNA Glycosylase (UDG) and Endonuclease VIII, provided at a 10X concentration to be added to a reaction containing a uracil-containing polynucleotide sequence. UDG catalyses the excision of the uracil base, creating an abasic site with an intact phosphodiester backbone (1,2). The lyase activity of Endonuclease VIII breaks the phosphodiester backbone both 3’ and 5’ to the abasic site, liberating the deoxyribose sugar (3,4).
Source of Protein :
Each component protein is purified separately from E. coli strains containing recombinant Endonuclease VIII and Uracil-DNA Glycosylase genes.