How cations change peptide structure.

@article{Baldauf2013HowCC,
  title={How cations change peptide structure.},
  author={Carsten Baldauf and Kevin Pagel and Stephan Warnke and Gert von Helden and Beate Koksch and Volker Blum and Matthias Scheffler},
  journal={Chemistry},
  year={2013},
  volume={19 34},
  pages={
          11224-34
        }
}
Specific interactions between cations and proteins have a strong impact on peptide and protein structure. Herein, we shed light on the nature of the underlying interactions, especially regarding effects on the polyamide backbone structure. This was done by comparing the conformational ensembles of model peptides in isolation and in the presence of either Li(+) or Na(+) by using state-of-the-art density-functional theory (including van der Waals effects) and gas-phase infrared spectroscopy… 

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