Unconventional interactions between water and heterocyclic nitrogens in protein structures.

@article{Stollar2004UnconventionalIB,
  title={Unconventional interactions between water and heterocyclic nitrogens in protein structures.},
  author={Elliott J Stollar and Jos{\'e} Luis Gelp{\'i} and Sameer Velankar and Adel Golovin and Modesto Orozco and Ben F Luisi},
  journal={Proteins},
  year={2004},
  volume={57 1},
  pages={1-8}
}
We report an unusual interaction in which a water molecule approaches the heterocyclic nitrogen of tryptophan and histidine along an axis that is roughly perpendicular to the aromatic plane of the side chain. The interaction is distinct from the well-known conventional aromatic hydrogen-bond, and it occurs at roughly the same frequency in protein structures. Calculations indicate that the water-indole interaction is favorable energetically, and we find several cases in which such contacts are… CONTINUE READING