Different efficiencies of the Tag and AlkA DNA glycosylases from Escherichia coli in the removal of 3-methyladenine from single-stranded DNA

FEBS Lett. 1996 Nov 11;397(1):127-9. doi: 10.1016/s0014-5793(96)01166-0.

Abstract

Escherichia coli possesses two different DNA repair glycosylases, Tag and AlkA, which have similar ability to remove the alkylation product 3-methyladenine from double-stranded DNA. In this study we show that these enzymes have quite different activities for the excision of 3-methyladenine from single-stranded DNA, AlkA being 10-20 times more efficient than Tag. We propose that AlkA and perhaps other glycosylases as well may have an important role in the excision of base damage from single-stranded regions transiently formed in DNA during transcription and replication.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenine / analogs & derivatives*
  • Adenine / metabolism
  • Alkylation
  • DNA Glycosylases*
  • DNA Repair*
  • DNA, Single-Stranded / metabolism*
  • Escherichia coli / enzymology*
  • Methylation
  • N-Glycosyl Hydrolases / metabolism*
  • Poly A / metabolism
  • Poly dA-dT / metabolism

Substances

  • DNA, Single-Stranded
  • Poly A
  • poly(dA)
  • Poly dA-dT
  • 3-methyladenine
  • 3-methyladenine-DNA glycosylase
  • DNA Glycosylases
  • N-Glycosyl Hydrolases
  • DNA-3-methyladenine glycosidase II
  • Adenine