Generation of high-affinity DNA aptamers using an expanded genetic alphabet

@article{Kimoto2013GenerationOH,
  title={Generation of high-affinity DNA aptamers using an expanded genetic alphabet},
  author={Michiko Kimoto and Rie Yamashige and Ken-ichiro Matsunaga and Shigeyuki Yokoyama and Ichiro Hirao},
  journal={Nature Biotechnology},
  year={2013},
  volume={31},
  pages={453-457}
}
DNA aptamers produced with natural or modified natural nucleotides often lack the desired binding affinity and specificity to target proteins. Here we describe a method for selecting DNA aptamers containing the four natural nucleotides and an unnatural nucleotide with the hydrophobic base 7-(2-thienyl)imidazo[4,5-b]pyridine (Ds). We incorporated up to three Ds nucleotides in a random sequence library, which is expected to increase the chemical and structural diversity of the DNA molecules… 
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