Control of ion selectivity in potassium channels by electrostatic and dynamic properties of carbonyl ligands

@article{Noskov2004ControlOI,
  title={Control of ion selectivity in potassium channels by electrostatic and dynamic properties of carbonyl ligands},
  author={Sergei Yu. Noskov and Simon Bern{\`e}che and Beno{\^i}t Roux},
  journal={Nature},
  year={2004},
  volume={431},
  pages={830-834}
}
Potassium channels are essential for maintaining a normal ionic balance across cell membranes. Central to this function is the ability of such channels to support transmembrane ion conduction at nearly diffusion-limited rates while discriminating for K+ over Na+ by more than a thousand-fold. This selectivity arises because the transfer of the K+ ion into the channel pore is energetically favoured, a feature commonly attributed to a structurally precise fit between the K+ ion and carbonyl groups… 

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