s is ▁of ▁alk yl ated ▁DNA , ▁re le asing ▁ 3 - m eth yl aden ine , ▁ 3 - m eth yl gu an ine , ▁ 7 - m eth yl gu an ine , ▁and ▁ 7 - m eth yl aden ine ▁ ▁In vol ved ▁in ▁the ▁removal ▁of ▁alk yl ated ▁bases ▁from ▁DNA ▁in ▁E scher ich ia ▁col i . ▁ ▁E volution ▁▁ ▁Through ▁the ▁process ▁of ▁conver gent ▁evolution , ▁there ▁are ▁at ▁least ▁two ▁un related ▁protein ▁fol ds ▁that ▁share ▁the ▁same ▁DNA - 3 - m eth yl aden ine ▁g ly cos yl ase ▁activity . ▁The ▁first , ▁the ▁Al k A ▁N - term inal ▁domain , ▁is ▁found ▁in ▁b acter ia ▁. ▁ ▁The ▁second , ▁m eth yl pur ine - D NA ▁g ly cos yl ase ▁( MP G ) ▁ ▁is ▁found ▁in ▁verte br ates ▁including ▁humans . ▁ ▁N omen cl ature ▁▁ ▁DNA - 3 - m eth yl aden ine ▁g ly cos yl ase ▁II ▁is ▁also ▁known ▁as ▁▁ ▁de ox y rib on uc le ate ▁ 3 - m eth yl aden ine ▁g ly cos ides ▁II ▁▁ 3 - m eth yl aden ine ▁DNA ▁g ly cos yl ase ▁II ▁ ▁DNA - 3 - m eth yl aden ine ▁g ly cos ides ▁II ▁ ▁Al k A ▁ ▁alk yl ated - D NA ▁g