 These enzymes are primarily from bacteria, and have both DNA glycosylase activity and AP lyase activity .Examples include formamidopyrimidine-DNA glycosylases (Fpg; MutM) and endonuclease VIII (Nei).Formamidopyrimidine-DNA glycosylases (Fpg, MutM) is a trifunctional DNA base excision repair enzyme that removes a wide range of oxidation-damaged bases (N-glycosylase activity; ) and cleaves both the 3'- and 5'-phosphodiester bonds of the resulting apurinic/apyrimidinic site (AP lyase activity;).