Uracil-DNA glycosylases are widespread enzymes that are found in all living organisms. EC
3.2.2.27 and double-stranded uracil-DNA glycosylase (EC
3.2.2.28) form a central part of the DNA-repair machinery since they initiate the DNA base-excision repair pathway by hydrolysing the N-glycosidic bond between uracil and the deoxyribose sugar thereby catalysing the removal of mis-incorporated uracil from DNA.