3-Methyladenine DNA glycosylase I is an unexpected helix-hairpin-helix superfamily member

Alexander C. Drohat, Keehwan Kwon, Daniel J. Krosky, James T. Stivers

Research output: Contribution to journalArticlepeer-review


The Escherichia coli enzyme 3-methyladenine DNA glycosylase I (TAG) hydrolyzes the glycosidic bond of 3-methyladenine (3-MeA) in DNA and is found in many bacteria and some higher eukaryotes. TAG shows little primary sequence identity with members of the well-known helix-hairpin-helix (HhH) superfamily of DNA repair glycosylases, which consists of AlkA, EndoIII, MutY and hOGG1. Unexpectedly, the three-dimensional solution structure reported here reveals TAG as member of this superfamily. The restricted specificity of TAG for 3-MeA bases probably arises from its unique aromatic rich 3-MeA binding pocket and the absence of a catalytic aspartate that is present in all other HhH family members.

Original languageEnglish (US)
Pages (from-to)659-664
Number of pages6
JournalNature structural biology
Issue number9
StatePublished - Sep 2002

ASJC Scopus subject areas

  • Structural Biology
  • Biochemistry
  • Genetics

Fingerprint Dive into the research topics of '3-Methyladenine DNA glycosylase I is an unexpected helix-hairpin-helix superfamily member'. Together they form a unique fingerprint.

Cite this