8-oxodGTP incorporation by DNA polymerase beta is modified by active-site residue Asn279. Miller, H., Prasad, R., Wilson, S. H., Johnson, F., & Grollman, A. P. Biochemistry, 39(5):1029-33, 2, 2000.
8-oxodGTP incorporation by DNA polymerase beta is modified by active-site residue Asn279. [link]Mendeley  8-oxodGTP incorporation by DNA polymerase beta is modified by active-site residue Asn279. [link]Paper  abstract   bibtex   
To understand how the active site of a DNA polymerase might modulate the coding of 8-oxo-7,8-dihydrodeoxyguanine (8-oxodG), we performed steady-state kinetic analyses using wild-type DNA polymerase beta (pol beta) and two active-site mutants. We compared the coding of these polymerases by calculating the ratio of efficiencies for incorporation of dATP and dCTP opposite 8-oxodG and for incorporation of 8-oxodGTP opposite dA and dC. For wild-type pol beta, there is a 2:1 preference for incorporation of dCTP over dATP opposite 8-oxodG using a 5'-phosphorylated 4-base gap substrate. Mutation of either Asn279 or Arg283 to alanine has almost no effect on the ratio. 8-OxodGTP is preferentially incorporated opposite a template dA (24:1) by wild-type pol beta; mutation of Asn279 to alanine results dramatic change whereby there is preferential incorporation of 8-oxodGTP opposite dC (14:1). This suggests that interactions of 8-oxodGTP with Asn279 in the polymerase active site may alter the conformation of 8-oxodGTP and therefore alter its misincorporation.
@article{ mendeley_4996784552,
  isauthor = {1},
  abstract = {To understand how the active site of a DNA polymerase might modulate the coding of 8-oxo-7,8-dihydrodeoxyguanine (8-oxodG), we performed steady-state kinetic analyses using wild-type DNA polymerase beta (pol beta) and two active-site mutants. We compared the coding of these polymerases by calculating the ratio of efficiencies for incorporation of dATP and dCTP opposite 8-oxodG and for incorporation of 8-oxodGTP opposite dA and dC. For wild-type pol beta, there is a 2:1 preference for incorporation of dCTP over dATP opposite 8-oxodG using a 5'-phosphorylated 4-base gap substrate. Mutation of either Asn279 or Arg283 to alanine has almost no effect on the ratio. 8-OxodGTP is preferentially incorporated opposite a template dA (24:1) by wild-type pol beta; mutation of Asn279 to alanine results dramatic change whereby there is preferential incorporation of 8-oxodGTP opposite dC (14:1). This suggests that interactions of 8-oxodGTP with Asn279 in the polymerase active site may alter the conformation of 8-oxodGTP and therefore alter its misincorporation.},
  month = {2},
  canonical_id = {4ffc6b00-6d09-11df-a474-0026b95e3e23},
  added = {1339234597},
  year = {2000},
  keywords = {Asparagine, Asparagine: genetics, Asparagine: metabolism, Binding Sites, Binding Sites: genetics, Deoxyguanine Nucleotides, Deoxyguanine Nucleotides: genetics, Deoxyguanine Nucleotides: metabolism, Deoxyguanosine, Deoxyguanosine: analogs & derivatives, Deoxyguanosine: metabolism, DNA Polymerase beta, DNA Polymerase beta: genetics, DNA Polymerase beta: metabolism, Humans, Kinetics, Mutagens, Mutagens: metabolism, Nucleic Acid Conformation, Oligodeoxyribonucleotides, Oligodeoxyribonucleotides: chemical synthesis, Oligodeoxyribonucleotides: metabolism, Substrate Specificity, Substrate Specificity: genetics, Templates, Genetic},
  isstarred = {0},
  id = {4996784552},
  discipline = {Computer and Information Science},
  journal = {Biochemistry},
  title = {8-oxodGTP incorporation by DNA polymerase beta is modified by active-site residue Asn279.},
  day = {8},
  deletionpending = {0},
  version = {1339234654},
  pmid = {10653647},
  number = {5},
  url_mendeley = {http://www.mendeley.com//research/8-oxodgtp-incorporation-dna-polymerase-beta-modified-active-site-residue-asn279-1//},
  volume = {39},
  isread = {0},
  author = {H {Miller} and R {Prasad} and S H {Wilson} and F {Johnson} and A P {Grollman}},
  pages = {1029-33},
  url = {http://www.ncbi.nlm.nih.gov/pubmed/10653647},
  type = {Journal Article},
  issn = {0006-2960},
  modified = {1339234654},
  subdiscipline = {Information Science},
  journal = {Biochemistry},
  dateaccessed = {09/06/12}
}

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