PMID:17641464

From EcoliWiki
Jump to navigation Jump to search
Citation

Yonekura, S, Nakamura, N, Doi, T, Sugiyama, H, Yamamoto, K, Yonei, S and Zhang, QM (2007) Recombinant Schizosaccharomyces pombe Nth1 protein exhibits DNA glycosylase activities for 8-oxo-7,8-dihydroguanine and thymine residues oxidized in the methyl group. J. Radiat. Res. 48:417-24

Abstract

Bacteria and eukaryotes possess redundant enzymes that recognize and remove oxidatively damaged bases from DNA through base excision repair. DNA glycosylases remove damaged bases to initiate the base excision repair. The exocyclic methyl group of thymine does not escape oxidative damage to produce 5-formyluracil (5-foU) and 5-hydroxymethyluracil (5-hmU). 5-foU is a potentially mutagenic lesion. A homolog of E. coli endonuclease III (SpNth1) had been identified and characterized in Schizosaccharomyces pombe. In this study, we found that SpNth1 recognizes and removes 5-foU and 5-hmU from DNA with similar efficiency. The specific activities for the removal of 5-foU and 5-hmU were comparable with that for thymine glycol. The expression of SpNth1 reduced the hydrogen peroxide toxicity and the frequency of spontaneous mutations in E. coli nth nei mutant. It was also revealed that SpNth1 had DNA glycosylase activity for removing 8-oxo-7,8-dihydroguanine (8-oxoG) from 8-oxoG/G and 8-oxoG/A mispairs. These results indicated that SpNth1 has a broad substrate specificity and is involved in the base excision repair of 8-oxoG and thymine residues oxidized in the methyl group in S. pombe.

Links

PubMed

Keywords

DNA Glycosylases/genetics; DNA Glycosylases/metabolism; DNA Methylation; DNA Repair/physiology; DNA-(Apurinic or Apyrimidinic Site) Lyase/genetics; DNA-(Apurinic or Apyrimidinic Site) Lyase/metabolism; Guanine/chemistry; Guanine/metabolism; Multienzyme Complexes/genetics; Multienzyme Complexes/metabolism; Oxidation-Reduction; Recombinant Proteins/chemistry; Recombinant Proteins/metabolism; Schizosaccharomyces/enzymology; Schizosaccharomyces/genetics; Schizosaccharomyces pombe Proteins/genetics; Schizosaccharomyces pombe Proteins/metabolism; Thymine/chemistry; Thymine/metabolism

Significance

You can help EcoliWiki by summarizing why this paper is useful

Useful Materials and Methods

You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.

Annotations

<annotationlinks/>

EcoliWiki Links

Add links to pages that link here (e.g. gene, product, method pages)

References

See Help:References for how to manage references in EcoliWiki.