DNA glycosylase

The DNA glycosylases are DNA repair enzymes that can detect and repair the damage to the DNA. They are part of the base excision repair of the cell.

The glycosylases recognize damaged bases and remove them from their Desoxyribosephosphatgerüst. So that an AP site in the DNA is generated ( or apyrimidinic Apurinstelle ). Now, an endonuclease open the DNA strand at the defect site and remove the deoxyribose. A polymerase replaces the nucleoside and the DNA strand is closed by a DNA ligase.