A four-base paired genetic helix with expanded size.

@article{Liu2003AFP,
  title={A four-base paired genetic helix with expanded size.},
  author={Haibo Liu and Jianmin Gao and Stephen R. Lynch and Yoshihito D Saito and Lystranne Maynard and Eric T. Kool},
  journal={Science},
  year={2003},
  volume={302 5646},
  pages={868-71}
}
We describe a new molecular class of genetic-pairing system that has a native DNA backbone but has all four base pairs replaced by new, larger pairs. The base pairs include size-expanded analogs of thymine and of adenine, both extended by the width of a benzene ring (2.4 A). The expanded-diameter double helices are more thermodynamically stable than the Watson-Crick helix, likely because of enhanced base stacking. Structural data confirm a right-handed, double-stranded, and base-paired helical… CONTINUE READING